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Sample records for arctic sediments svalbard

  1. Diversity and distribution of fungal communities in the marine sediments of Kongsfjorden, Svalbard (High Arctic)

    Science.gov (United States)

    Zhang, Tao; Fei Wang, Neng; Qin Zhang, Yu; Yu Liu, Hong; Yan Yu, Li

    2015-10-01

    This study assessed the diversity and distribution of fungal communities in eight marine sediments of Kongsfjorden (Svalbard, High Arctic) using 454 pyrosequencing with fungal-specific primers targeting the internal transcribed spacer (ITS) region of the ribosomal rRNA gene. Sedimentary fungal communities showed high diversity with 42,219 reads belonging to 113 operational taxonomic units (OTUs). Of these OTUs, 62 belonged to the Ascomycota, 26 to Basidiomycota, 2 to Chytridiomycota, 1 to Zygomycota, 1 to Glomeromycota, and 21 to unknown fungi. The major known orders included Hypocreales and Saccharomycetales. The common fungal genera were Pichia, Fusarium, Alternaria, and Malassezia. Interestingly, most fungi occurring in these Arctic sediments may originate from the terrestrial habitats and different basins in Kongsfjorden (i.e., inner basin, central basin, and outer basin) harbor different sedimentary fungal communities. These results suggest the existence of diverse fungal communities in the Arctic marine sediments, which may serve as a useful community model for further ecological and evolutionary study of fungi in the Arctic.

  2. Organic carbon degradation in arctic marine sediments, Svalbard: A comparison of initial and terminal steps

    DEFF Research Database (Denmark)

    Arnosti, C.; Jørgensen, BB

    2006-01-01

    carbohydrate concentrations were comparable to those measured in more temperate sediments, and likely comprise a considerable fraction of porewater dissolved organic carbon. A comparison of dissolved carbohydrate inventories with hydrolysis and sulfate reduction rates suggests that the turnover of carbon......Degradation of marine organic matter under anoxic conditions involves microbial communities working in concert to remineralize complex substrates to CO2. In order to investigate the coupling between the initial and terminal steps of this sequence in permanently cold sediments, rates of...... extracellular enzymatic hydrolysis and sulfate reduction were measured in parallel cores collected from 5 fjords on the west and northwest coast of Svalbard, in the high Arctic. Inventories of total dissolved carbohydrates were also measured in order to evaluate their potential role in carbon turnover...

  3. Identifying nitrogen limitations to organic sediments accumulation in various vegetation types of arctic tundra (Hornsund, Svalbard)

    Science.gov (United States)

    Skrzypek, G.; Wojtuń, B.; Hua, Q.; Richter, D.; Jakubas, D.; Wojczulanis-Jakubas, K.; Samecka-Cymerman, A.

    2015-12-01

    Arctic and subarctic regions play important roles in the global carbon balance. However, nitrogen (N) deficiency is a major constraint for organic carbon sequestration in the High Arctic. Hence, the identification of the relative contributions from different N-sources is critical for understanding the constraints that limit tundra growth. The stable nitrogen composition of the three main N-sources and numerous plants were analyzed in ten tundra types in the Fuglebekken catchment (Hornsund Fjord, Svalbard, 77°N 15°E). The percentage of the total tundra N-pool provided by seabirds' feces (colonially breeding, planktivorous Alle alle), ranged from 0-21% in Patterned-ground tundra to 100% in Ornithocoprophilous tundra. The total N-pool utilized by tundra plants in the studied catchment was built in 36% by birds, 38% by atmospheric deposition, and 26% by N2-fixation. The results clearly show that N-pool in the tundra is significantly supplemented by nesting seabirds. Thus, if they experienced substantial negative environmental pressure associated with climate change, it would adversely influence the tundra N-budget [1]. The growth rates and the sediment thickness (climatic conditions but also by birds' contribution to the tundra N-pool. [1] Skrzypek G, Wojtuń B, Richter D, Jakubas D, Wojczulanis-Jakubas K, Samecka-Cymerman A, 2015. Diversification of nitrogen sources in various tundra vegetation types in the high Arctic. PLoS ONE (in review).

  4. Oxygen distribution and bioirrigation in Arctic fjord sediments (Svalbard, Barents Sea)

    DEFF Research Database (Denmark)

    Jørgensen, BB; Glud, RN; Holby, O.

    2005-01-01

    total oxygen uptake of the sediments as measured in situ by a flux chamber lander. The sediments were densely populated by fauna such as tube-dwelling polychaetes. Inhabited and relict tubes of 1 to 2.5 mm diameter reached densities of up to 1 cm(-2), and about 15 % of all oxygen microprofiles showed...... composite, 2-dimensional images of the oxygen distribution. Oxygen penetrations ranged from 3 to 11 min with a mean depth of 6 to 8 mm. The mean diffusive oxygen uptake rates across the sediment-water interface ranged from 2.8 to 13.4 mmol O-2 m(-2) d(-1). The diffusive flux accounted for 60 to 95% of the...... evidence of advective oxygen flow through the tubes. Based on oxygen microprofiles and data on burrow geometry and density, burrows extending down into the anoxic sediment extended the oxic sediment volume by 2 to 10 % and thereby enhanced the oxygen flux. Anoxic microenvironments were not detected, but...

  5. Desulfuromonas svalbardensis sp nov and Desulfuromusa ferrireducens sp nov., psychrophilic, Fe(III)-reducing bacteria isolated from Arctic sediments, Svalbard

    DEFF Research Database (Denmark)

    Vandieken, V.; Mussmann, M.; Niemann, Hans Henrik;

    2006-01-01

    Two psychrophilic, Gram-negative, rod-shaped, motile bacteria (strains 112(T) and 102(T)) that conserved energy from dissimilatory Fe(III) reduction concomitant with acetate oxidation were isolated from permanently cold Arctic marine sediments. Both strains grew at temperatures down to -2 degrees C...... substrate. As alternatives to Fe(III), they reduced fumarate, S-0 and Mn(IV). Based on 16S rRNA gene sequence similarity, strain 112(T) was most closely related to Desulfuromonas acetoxidans (97.0%) and Desulfuromonas thiophila NZ27(T) (95.5 %), and strain 102(T) to Malonomonas rubra Gra Mal 1(T) (96...

  6. Verrucomicrobia Are Candidates for Polysaccharide-Degrading Bacterioplankton in an Arctic Fjord of Svalbard

    OpenAIRE

    Cardman, Z.; C. Arnosti; Durbin, A.; Ziervogel, K.; Cox, C; A. D. Steen; Teske, A

    2014-01-01

    In Arctic marine bacterial communities, members of the phylum Verrucomicrobia are consistently detected, although not typically abundant, in 16S rRNA gene clone libraries and pyrotag surveys of the marine water column and in sediments. In an Arctic fjord (Smeerenburgfjord) of Svalbard, members of the Verrucomicrobia, together with Flavobacteria and smaller proportions of Alpha- and Gammaproteobacteria, constituted the most frequently detected bacterioplankton community members in 16S rRNA gen...

  7. Pathways of carbon oxidation in an Arctic fjord sediment (Svalbard) and isolation of psychrophilic and psychrotolerant Fe(III)-reducing bacteria

    DEFF Research Database (Denmark)

    Vandieken, Verona; Finke, Niko; Jørgensen, Bo Barker

    2006-01-01

    The main mineralization pathways were determined in permanently cold fjord sediment on the west coast of Svalbard. In whole core incubations, the total oxygen uptake rate was 4.2 ± 0.4 mmol m–2 d–1 and the sulfate reduction rate 2.6 ± 0.6 mmol m–2 d–1 at 0 to 20 cm depth. Sulfate reduction was th...

  8. Microbial methane oxidation in the Arctic Ocean offshore Svalbard

    Science.gov (United States)

    Steinle, Lea I.; Graves, Carolyn; Lehmann, Moritz F.; Treude, Tina; Niemann, Helge

    2013-04-01

    Large amounts of methane are released from ocean sediments, most importantly at cold seep environments. Aerobic methanotrophic bacteria in the ocean water column consume a significant fraction of this biogenic methane, preventing its emission to the atmosphere. The understanding of key environmental factors controlling the efficiency of this biological methane-filter is still incomplete. In order to elucidate possible environmental constraints on methane turnover in the ocean, we investigated the temporal and spatial variation of aerobic methane oxidation (MOx) rates at active cold seeps at water depths between 150 and 400 m, located off the coast of Svalbard. In the study area, methane concentrations were consistently elevated in bottom waters (up to 825 nM) and decreased towards the sea surface. Highest MOx rates of up to 3.1 nM/day were typically observed at ~30 m above the sea floor. Despite the constant supply of methane substrate, MOx rates displayed a high temporal variability. Comparison of the distribution of MOx rates and water temperature revealed consistent spatio-temporal patterns suggesting an oceanographic control on the magnitude of MOx: Cool Arctic bottom waters containing a comparably large standing stock of methanotrophic bacteria are episodically displaced by the warmer W-Spitsbergen current, which meanders along the Svalbard continental margin and is depleted in methanotrophic biomass. As a consequence, methane is injected into warmer water masses containing fewer methanotrophs, and overall methane oxidation is reduced. While the primary cause for the observed discrepancy in methanotrophic activity between the different water masses is still uncertain, our preliminary data indicate that MOx fluctuations in the ocean water column above the Svalbard cold seeps are modulated by ocean circulation patterns and the associated differential supply of bacterial stock.

  9. Distribution and autecology of chrysophyte cysts from high Arctic Svalbard lakes: preliminary evidence of recent environmental change

    OpenAIRE

    Betts-Piper, Alexandra M.; Zeeb, Barbara A.; John P. Smol

    2004-01-01

    Chrysophycean stomatocyst assemblages were analysed from the sediments of 17 lakes and ponds from Svalbard as one component of a multi-proxy investigation of recent environmental change in the high Arctic. Sediment cores and water chemistry were collected from each of the study lakes, and chrysophyte stomatocysts were investigated from the top 0.25 cm of sediment (present-day) and bottom (i.e. bottom of short sediment core, pre-industrial) sediment samples. This study represents the first und...

  10. Carbon mineralization in Arctic sediments northeast of Svalbard: Mn(IV) and Fe(III) reduction as principal anaerobic respiratory pathways

    DEFF Research Database (Denmark)

    Vandieken, Verona; Nickel, Maren; Jørgensen, Bo Barker

    2006-01-01

    Carbon oxidation rates and pathways were determined in 3 sediments at latitude 79 degrees to 81 degrees N in the Barents Sea, where the ice cover restricts primary production to a few months of the year. Oxygen uptake (1.5 to 3.5 imnol m(-2) d(-1)) and sulfate reduction (= 60 mu mol cm(-3)) and Fe......(III) (>= 108 mu mol cm(-3)), dissimilatory Mn(IV) and Fe(III) reduction contributed between 69 and >= 90% to anaerobic carbon mineralization in the upper 10 cm of the sediments. At 2 of the 3 stations, sulfate reduction rates were below our detection limit of 1 nmol cm(-3) d(-1). Solid Mn and Fe(III) were...... and sulfate reduction at 5 to 10 cm. Rates of microbial carbon oxidation were low compared to those in fjords on the west and south coasts of Svalbard. This is in accordance with the limited organic carbon supply by primary and secondary productivity caused by long periods of ice coverage....

  11. The origin and transport of pollutant lead (Pb) to the Svalbard area of the Arctic

    International Nuclear Information System (INIS)

    Full text: Monitoring of pollutants in the biota of the Arctic is a high priority activity of the circumpolar Arctic nations. Considerable, research has been directed at understanding the influence of pollutants on the Arctic ecosystem. The majority of research in the Svalbard area of the Arctic has concentrated on the levels of persistent organic pollutants (POPs) such as PCBs in the biota of the area. More recently the role of heavy metal pollutants such as mercury (Hg), cadmium (Cd) and lead (Pb) in the arctic ecosystem has been highlighted. A possible major sink/source for contaminants are sediments however very little research has been undertaken in the sediments of the Svalbard area. To fully understand the system and allow preventative or remedial steps to be taken, it is necessary to determine the magnitude of pollutant inputs and the major transport pathways. By investigating sediment cores from lakes, fjordic and shelf environments surrounding the Svalbard area it will be possible to understand these processes and assess their importance in modelling the fate of contaminants within the Arctic environment. By utilising stable Pb isotopes (206Pb, 207Pb and 208Pb) it is possible to identify the source from which it came. For example, in the UK, Pb from petrol has a 206Pb/207Pb ratio of 1.092, industrial sources have a ratio of around 1.18, and natural sources vary but are typically around 1.20. Therefore by measuring the isotopic ratio of the Pb contained in the Svalbard sediments it is possible to determine what the predominant sources of pollutant Pb are. Sediment cores from a north-south transect (Voering Plateau to the Yermak Plateau) and from an east-west transect (Kongsfjorden to Fram Strait) have been analysed for trace element and heavy metal concentrations and stable Pb isotope ratios. To determine the relative importance of atmospheric transport versus marine transport sediment lake cores have been analysed and compared with the cores from

  12. Desulfuromonas svalbardensis sp. nov. and Desulfuromusa ferrireducens sp. nov., psychrophilic, Fe(III)-reducing bacteria isolated from Arctic sediments, Svalbard

    DEFF Research Database (Denmark)

    Vandieken, Verona; Mussmann, Marc; Niemann, Helge;

    2006-01-01

    Two psychrophilic, Gram-negative, rod-shaped, motile bacteria (strains 112T and 102T) that conserved energy from dissimilatory Fe(III) reduction concomitant with acetate oxidation were isolated from permanently cold Arctic marine sediments. Both strains grew at temperatures down to -2 degrees C....... As alternatives to Fe(III), they reduced fumarate, S0 and Mn(IV). Based on 16S rRNA gene sequence similarity, strain 112T was most closely related to Desulfuromonas acetoxidans (97.0 %) and Desulfuromonas thiophila NZ27T (95.5 %), and strain 102T to Malonomonas rubra Gra Mal 1T (96.3 %) and...

  13. Desultovibrio frigidus sp nov and Desulfovibrio ferfireducens sp nov., psychrotolerant bacteria isolated from Arctic fiord sediments (Svalbard) with the ability to reduce Fe(III)

    DEFF Research Database (Denmark)

    Vandieken, V.; Knoblauch, C.; Jørgensen, BB

    2006-01-01

    Strains 18(T) 61(T) and 77 were isolated from two permanently cold fjord sediments on the west coast of Svalbard. The three psychrotolerant strains, with temperature optima at 20-23 degrees C, were able to grow at the freezing point of sea water, -2 degrees C. The strains oxidized important...... absence of electron acceptors, fermentative growth was possible. The pH optimum for the strains was around 7(.)1. The DNA G+C contents were 43(.)3 and 42(.)0 mol% for strains 18(T) and 61(T), respectively. Strains 18(T) 61(T) and 77 were most closely related to Desulfovibrio hydrothermalis (95......(.)0-95(.)7% 16S rRNA gene sequence similarity), Strains 18(T) and 77, exhibiting 99(.)9% sequence similarity, represent a novel species for which the name Desulfovibrio frigidus sp. nov. is proposed. The type strain is strain 18(T) (=DSM 17176(T)=jCM 12924(T)). Strain 61(T) was closely related to strains 18(T...

  14. Aerosol black carbon over Svalbard regions of Arctic

    Science.gov (United States)

    Gogoi, Mukunda M.; Babu, S. Suresh; Moorthy, K. Krishna; Thakur, Roseline C.; Chaubey, Jai Prakash; Nair, Vijayakumar S.

    2016-03-01

    In view of the climate impact of aerosol Black Carbon (BC) over snow covered regions (through enhanced absorption of radiation as well as snow-albedo forcing), and in view of the increasing anthropogenic presence and influence in the northern polar regions, continuous long term measurements of airborne BC have been undertaken from the Svalbard region of Norwegian Arctic (Ny-Ålesund, 79°N, 12°E, 8 m a.s.l.). This study, employing data over a period of 4-years (2010-2013) have shown a consistent spring-time enhancement in BC concentrations, having a (climatological) seasonal mean value of ∼50.3 ± 19.5 ng m-3, nearly 3-times higher than the lowest BC concentrations in summer (∼19.5 ± 6.5 ng m-3). Spectral variation of absorbance indicates that long-range transported biomass burning aerosols contribute as high as 25% to the high BC concentrations in the Arctic atmosphere in spring. Concurrent estimates of BC concentrations in the Arctic snow (for an ensemble of snow samples collected over a period of time during spring) showed values ranging from 0.6 ppb to 4.1 ppb. These values have been used to estimate the BC scavenging ratio (SR). Our studies revealed a mean value of SR ∼98 ± 46, which varied over wide range from 40 to 184 for individual samples. In a broader perspective, the seasonal variations of atmospheric BC concentrations at the Arctic are similar to those seen at the high altitude Himalayas; even though the concentrations are much lower at Arctic. It is found that synoptic conditions mainly influence the high altitude Himalayas, while the influences of local anthropogenic influences are not negligible at the Arctic in modulating the seasonal variations of absorbing aerosols.

  15. Net atmospheric mercury deposition to Svalbard: Estimates from lacustrine sediments

    Science.gov (United States)

    Drevnick, Paul E.; Yang, Handong; Lamborg, Carl H.; Rose, Neil L.

    2012-11-01

    In this study we used lake sediments, which faithfully record Hg inputs, to derive estimates of net atmospheric Hg deposition to Svalbard, Norwegian Arctic. With the exception of one site affected by local pollution, the study lakes show twofold to fivefold increases in sedimentary Hg accumulation since 1850, likely due to long-range atmospheric transport and deposition of anthropogenic Hg. Sedimentary Hg accumulation in these lakes is a linear function of the ratio of catchment area to lake area, and we used this relationship to model net atmospheric Hg flux: preindustrial and modern estimates are 2.5 ± 3.3 μg m-2 y-1 and 7.0 ± 3.0 μg m-2 y-1, respectively. The modern estimate, by comparison with data for Hg wet deposition, indicates that atmospheric mercury depletion events (AMDEs) or other dry deposition processes contribute approximately half (range 0-70%) of the net flux. Hg from AMDEs may be moving in significant quantities into aquatic ecosystems, where it is a concern because of contamination of aquatic food webs.

  16. Modern Process Studies in Kongsfjord, Svalbard: Arctic Geoscience Research Experience for U.S. Undergraduates (Svalbard REU)

    Science.gov (United States)

    Powell, R. D.; Brigham-Grette, J.

    2011-12-01

    The Svalbard REU (Research Experience for Undergraduates) program focuses on understanding how high latitude glaciers, meltwater streams, and sedimentation in lakes and fjords respond to changing climate. Since summer of 2004, six under-graduate students have been selected to participate in the summer field program. Students work on individual projects and in close conjunction with faculty advisors and other student researchers. They formulate their own research questions, develop their project, and complete their field research during a five-week program on Svalbard, Norway. Following the summer program, students complete their projects at their home institution during the following academic year as a senior thesis. A spring symposium brings all participants back together again with their final results. The most recent field season was completed in Kongsfjord (79N) showing that the contemporary studies of tidewater glacier margins provide an unparalleled opportunity for introducing motivated third year undergraduate students to the challenges and rewards of polar geoscientific field research. Rates of rapid change in this high-latitude Arctic environment emphasize the complexity of the Earth System at the interface of the ocean, atmosphere and cryosphere. Given background information in glacial and marine geology, glaciology, hydrology, climatology and fjord oceanography not routinely offered in undergraduate curricula, students develop the science questions to be addressed and establish a field plan for instrumentation and sampling. Working together in small boats in one of the most challenging natural environments, the students expand their leadership skills, learn the value of teamwork and collaborative data sharing while maintaining a strong sense of ownership over their individual science projects. The rigors of studying an actively calving tidewater glacier also builds on their outdoor skills, especially when it is necessary to improvise and become

  17. Towards a process-based understanding of Holocene polar climate change. Using glacier-fed lake sediments from Arctic Svalbard and Antarctic South Georgia

    OpenAIRE

    Bilt, Willem van der

    2016-01-01

    Earth`s polar regions are undergoing dramatic changes due to ongoing climate change as demonstrated by increasing temperatures, collapsing ice shelves, Arctic sea ice loss and rapid glacier retreat. Driving an accelerating rise in global sea level, this amplified regional response may have devastating global socio-economic consequences in the foreseeable future. Yet the causes and range of polar climate variability remain poorly understood as observational records are short and fragmentary, w...

  18. Differential methane oxidation activity and microbial community composition at cold seeps in the Arctic off western Svalbard

    Science.gov (United States)

    Gründger, Friederike; Svenning, Mette M.; Niemann, Helge; Silyakova, Anna; Serov, Pavel; Li Hong, Wei; Wegener, Gunter; Panieri, Giuliana; Carroll, JoLynn

    2016-04-01

    Most models considering climate change related bottom water warming suggest that gas hydrates may become destabilized, leading to the mobilization of methane into seabed and water column ecosystems, and, eventually, into the atmosphere. However, the capacity of methanotrophic microbes retaining methane in sediments and the hydrosphere is not well constrained. Here, we investigate the microbial utilization of methane in sediments and the water column, focusing on cold seeps discovered at the arctic continental margin of western Svalbard. We measured ex situ rates of methane oxidation and sulfate reduction in two active gas flare sites with different geological settings at the Vestnesa Ridge (1204 m water depth) and within a pingolike feature area southwest off Svalbard (PLF; 380 m water depth). Our results show contrarily situations at our two sampling sites: At Vestnesa Ridge we find high methane oxidation rates with values up to 2055 nmol cm‑3 d‑1 at the sediment surface where the sediments are oversaturated with methane. Whereas, methane concentration and oxidation rates are low in the overlying water column (2 pmol cm‑3 d‑1). In contrast, at the sediment surface at PLF methane concentration and oxidation rates are considerably lower (up to 1.8 nmol cm‑3 d‑1). While the overlying bottom water contains high concentration of methane and shows oxidation rates with values of up to 3.8 nmol cm‑3 d‑1. The data on methane oxidation and sulfate reduction activity are compared to the sediment geochemistry and to data from metagenomic analysis identifying the methanotrophic community composition. These results provide unique insight into the dynamic responses of the seabed biological filter at cold seeps in the Arctic off western Svalbard. This study is part of the Centre for Arctic Gas Hydrate, Environment and Climate and was supported by the Research Council of Norway through its Centres of Excellence funding scheme grant No. 223259.

  19. High Arctic Coasts At Risk - The Impact of Coastal Hazards on Scientific and Community Infrastructure in Svalbard

    Science.gov (United States)

    Strzelecki, M. C.; Pawlowski, L.; Jaskolski, M.; Lim, M.; Zagorski, P.; Long, A. J.; Jensen, M.

    2015-12-01

    The rapid climate warming being observed in the Svalbard is leading to an increase in human activities in the coastal zone, leading to an increased need for coastal hazard assessment. Present-day Svalbard coastal landscapes are modified by increased degradation of permafrost accelerated sediment supply from deglaciated catchments, and prolonged periods of open-water conditions and wave activity. Since the second half of 20thcentury there is also an observed increase in the number and intensity of storms entering the Arctic particularly in summer months when coastlines are free of protective ice cover. Despite the potential significance of these coastal hazards on the security of scientific (research bases and devices) and community (ports, airports, roads, buildings) infrastructure on Svalbard, relatively little is known on the present-day rate of Svalbard coastal zone changes and how they might impact the nearshore infrastructure in the future. Here we report the results of a project that focused on rates of coastal zone changes in Svalbard and examined the impact of extreme coastal processes on scientific and community infrastructure. The project applied combination of remote sensing and field-based mapping techniques to characterise coastal changes observed in the surroundings of main research stations in Svalbard in Hornsund (PPS), Petuniabukta (AMUPS) and Bellsund (Calypsobyen) as well as a major towns: Longyearbyen, Piramiden, Barentsburg and Svea. Our results document dramatic changes of Svalbard coastal zone under intervals characterised by a warming climate, retreating local ice masses, a shortened winter sea-ice season and melting permafrost. The study confirmed the growing importance of extreme processes in shaping coasts of Svalbard and the impact of these changes on human infrastructure. Our study proposes a risk assessment for a development and protection of infrastructure along the coasts of Svalbard under scenarios of climate change, sea level rise

  20. Desulfovibrio frigidus sp. nov. and Desulfovibrio ferrireducens sp. nov., psychrotolerant bacteria isolated from Arctic fjord sediments (Svalbard) with the ability to reduce Fe(III)

    DEFF Research Database (Denmark)

    Vandieken, Verona; Knoblauch, Christian; Jørgensen, Bo Barker

    2006-01-01

    Strains 18T, 61T and 77 were isolated from two permanently cold fjord sediments on the west coast of Svalbard. The three psychrotolerant strains, with temperature optima at 20-23 degrees C, were able to grow at the freezing point of sea water, -2 degrees C. The strains oxidized important fermenta......Strains 18T, 61T and 77 were isolated from two permanently cold fjord sediments on the west coast of Svalbard. The three psychrotolerant strains, with temperature optima at 20-23 degrees C, were able to grow at the freezing point of sea water, -2 degrees C. The strains oxidized important...... absence of electron acceptors, fermentative growth was possible. The pH optimum for the strains was around 7.1. The DNA G+C contents were 43.3 and 42.0 mol% for strains 18T and 61T, respectively. Strains 18T, 61T and 77 were most closely related to Desulfovibrio hydrothermalis (95.0-95.7 % 16S rRNA gene...... sequence similarity). Strains 18T and 77, exhibiting 99.9 % sequence similarity, represent a novel species for which the name Desulfovibrio frigidus sp. nov. is proposed. The type strain is strain 18T (=DSM 17176T = JCM 12924T). Strain 61T was closely related to strains 18T and 77 (97.6 and 97.5 % 16S r...

  1. Mechanism of Varve Formation and Paleoenvironmental Research at Lake Bolterskardet, Svalbard, the Arctic

    Institute of Scientific and Technical Information of China (English)

    CHU Guoqiang; LIU Jiaqi; GAO Denyi; SUN Qing

    2006-01-01

    On the basis of observation of thin sections and 137Cs data, laminations in sediment are interpreted to be varves in Bolterskardet Lake (78°06' N, 16°01' E), Svalbard, the Arctic. Varves appear under a petrologic microscope as couplets of dark-silt and light-clay layers. The mechanism of varve formation is surmized as follows: each silt layer is the production of sediment inflow interpreted as mainly derived from snowmelt during summer; each clay layer was deposited in a stillwater environment during an ice-cover period. A light -clay layer provides an important index bed to identify the annual interface. The high accumulation rates, long period of ice cover, and topographically closed basin are probably all critical factors in forming and preserving varves. Varve thickness is known to be controlled mainly by summer temperature. The variation of varve thickness in Lake Bolterskardet can then be used to reconstruct summer temperature. The varve series show that there has been distinct decade-scale variability of summer temperature over the past 150 years. Warm periods occurred in the 1860s, around 1900, the 1930s, 1950s, and 1970s, and in the last 20 years. The varved sediments of Lake Bolterskarde preserve an ideal record for high-resolution paleoclimatic and paleoenvironmental research in this data-sparse area.

  2. The invertebrate fauna of anthropogenic soils in the High-Arctic settlement of Barentsburg, Svalbard

    Directory of Open Access Journals (Sweden)

    Torstein Solhøy

    2013-05-01

    Full Text Available The terrestrial environment of the High Arctic consists of a mosaic of habitat types. In addition to the natural habitat diversity, various human-influenced types may occur. For the resident invertebrate fauna, these anthropogenic habitats may be either unusually favourable or detrimental. In the town of Barentsburg, Svalbard, soils were imported for the greenhouses from southern Russia. These soils were subsequently discarded outside the greenhouses and have become augmented with manure from the cowsheds. Both the greenhouse and the cowsheds are now derelict. This site represents an unusually nutrient-rich location with considerable development of organic soils, in stark contrast to the naturally forming organic soils in Svalbard, which are typically thin and nutrient poor. Few previous studies have examined the soil invertebrate communities of human-disturbed or -created habitats in the Arctic. In an often nutrient-poor terrestrial environment, it is unclear how the invertebrate fauna will react to such nutrient enhancement. In these soils, 46 species of invertebrates were determined. Eleven species have not been recorded from other habitats in Svalbard and are hence likely to have been introduced. The native species assemblage in the anthropogenic soils was not atypical for many natural sites in Svalbard. Despite the enriched organic soils and highly ameliorated winter temperature conditions, the soil invertebrate fauna biodiversity does not appear to be enhanced beyond the presence of certain probably introduced species.

  3. The invertebrate fauna of anthropogenic soils in the High-Arctic settlement of Barentsburg, Svalbard

    OpenAIRE

    Coulson, Steve J.; Fjellberg, Arne; Dariusz J. Gwiazdowicz; Lebedeva, Natalia V.; Elena N. Melekhina; Solhøy, Torstein; Erséus, Christer; Maraldo, Kristine; Miko, Ladislav; Schatz, Heinrich; Rüdiger M. Schmelz; Søli, Geir; Stur,Elisabeth

    2013-01-01

    The terrestrial environment of the High Arctic consists of a mosaic of habitat types. In addition to the natural habitat diversity, various human-influenced types may occur. For the resident invertebrate fauna, these anthropogenic habitats may be either unusually favourable or detrimental. In the town of Barentsburg, Svalbard, soils were imported for the greenhouses from southern Russia. These soils were subsequently discarded outside the greenhouses and have become augmented with manure from...

  4. Environmental contaminants in arctic foxes (Alopex lagopus) in Svalbard: Relationships with feeding ecology and body condition

    International Nuclear Information System (INIS)

    Adipose tissues from 20 arctic foxes (Alopex lagopus) of both sexes from Svalbard were analysed for polybrominated diphenyl ether (PBDE), polychlorinated biphenyl (PCB), p,p'-dichlorodiphenyltrichloroethane (DDE), chlordane, and hexachlorobenzene (HCB) concentrations. Gender (0.43 15N from muscle samples and showed significantly positive relationship with all contaminants, with the exception of HCB concentrations. This indicates that foxes feeding at high trophic levels had higher tissue contaminant levels as a result of bioaccumulation in the food chain. - High contaminant concentrations in the coastal ecotype of arctic fox may cause toxic health effects due to huge annual cyclic variation in storage and mobilisation of adipose tissue

  5. High arctic snow avalanche observations and modeling in Svalbard 2007-2009

    Science.gov (United States)

    Eckerstorfer, Markus; Christiansen, Hanne H.; Humlum, Ole

    2010-05-01

    Systematic snow avalanche observations, carried out by the Norklima CRYOSLOPE Svalbard research project 2007-2009, represent the first comprehensive study of periglacial slope processes and especially snow avalanches in a high arctic maritime landscape. The main focus is on snow avalanche types, their spatial distribution, timing and associated controlling meteorological and snow pack conditions. Another focus is on the classification of the snow pack in central Svalbard in terms of thickness, hardness, stratigraphy and most persistent weak layers that cause avalanching. As a result of increasing population and tourism, snow mobile transportation and other recreational use of the steep terrain has increased, especially during the last 10-15 years in Svalbard. Such winter activity takes place in a high relief, almost vegetation free landscape, affected by snow avalanches. We present results from the 3 years project period, as well as the methods used to collect observations on snow avalanches, the snow pack and the meteorological data along the most intensively used 70 km snow mobile tracks around Svalbard's main settlement Longyearbyen. This enables us to identify the main factors controlling snow avalanches. We have recorded the amount of traffic along the main snow mobile tracks in our snow avalanche affected study area by use of radar, for avalanche risk evaluation. We also exemplify the high arctic maritime snow climate as an important additional type of snow climate, and emphasize its characteristics. Along with the field work, numerical modeling of avalanche activity has been developed and tested during the winter 2008-2009, on a weekly basis. The modeling includes topography, geomorphology and vegetation as input data, along with daily meteorological observations on air temperature, wind, cloud cover and precipitation from two meteorological stations at different altitudes. Examples from this modeling experiment will be presented together with the collected

  6. Desulfotomaculum arcticum sp. nov., a novel spore-forming, moderately thermophilic, sulfate-reducing bacterium isolated from a permanently cold fjord sediment of Svalbard

    DEFF Research Database (Denmark)

    Vandieken, Verona; Knoblauch, Christian; Jørgensen, Bo Barker

    2006-01-01

    Strain 15T is a novel spore-forming, sulfate-reducing bacterium isolated from a permanently cold fjord sediment of Svalbard. Sulfate could be replaced by sulfite or thiosulfate. Hydrogen, formate, lactate, propionate, butyrate, hexanoate, methanol, ethanol, propanol, butanol, pyruvate, malate...... growth occurred at 44 degrees C. Therefore, strain 15T apparently cannot grow at in situ temperatures of Arctic sediments from where it was isolated, and it was proposed that it was present in the sediment in the form of spores. The DNA G+C content was 48.9 mol%. Strain 15T was most closely related to...

  7. Triassic Sequence Geological Development of the Arctic with focus on Svalbard and the Barents Shelf

    Energy Technology Data Exchange (ETDEWEB)

    Moerk, Atle

    1998-12-31

    Triassic rocks are of great interest for exploration in Arctic areas as they have proved to include both good hydrocarbon source rocks and potential hydrogen reservoir rocks. In this thesis, the stratigraphy and sedimentology of the Arctic Triassic successions are studied within a sequence stratigraphical framework. Inter-regional comparisons throughout the Arctic are based on comparisons of transgressive-regressive sequences. Improved dating of the studied sequences, and the recognition and correlation of sequence boundaries of second and third order, facilitate interpretation of facies distribution and the geological development both within and between the studied areas. Main emphasis is given to the Triassic succession of Svalbard and the Barents Shelf, which through this study is integrated within a circum-Arctic sequence stratigraphical framework. Good correspondence of the Triassic sequence boundaries between the different Arctic areas indicate that they are mainly controlled by eustacy, while decreasing correspondence of the sequence boundaries in the Jurassic and Cretaceous periods indicate that local and large scale tectonism becomes progressively more dominant in the circum-Arctic Realm through the Mesozoic Era. These hypotheses are further discussed. 701 refs., 110 figs., 12 tabs.

  8. The Hinlopen/Yermak Megaslide (north of Svalbard, Arctic Ocean): Size, Timing and Triggering

    Science.gov (United States)

    Winkelmann, D.; Stein, R.

    2006-12-01

    With increasing interest in slope stability issues on continental shelves the causes and trigger mechanism of submarine slides get more and more into the scientific focus. The extent of the Hinlopen/Yermak Megaslide north of Spitsbergen has been revised based on new acoustic and detailed bathymetric data. Its true geometry, with an affected area of at least 10,000 km2 and more than 2400 km3 involved sedimentary material, puts the megaslide among the largest exposed submarine slides worldwide. Details from the its internal structure give evidence for one main failure event during MIS 3 followed by repeated minor events. The megaside's geometry and internal physical appearance point to a tectonically induced partial shelf collapse around 30 kyr. BP. The timing coincides with the transition of the Kapp Ekholm Interstadial into Glaciation G of Svalbard (Mangerud et al., 1998) and the build-up phase of the Svalbard-Barents Sea Ice Sheet. Thus, the megaslide occurred during a period of falling sea level, increasing ice volume and, presumably, increasing glacio-tectonic activity. We conclude that the Hinlopen/Yermak Megaslide has been the consequence of the rapid onset of LGM-glaciation resulting in a drastic sea level drop, asymmetrical ice loading and a fore bulge development. For the final trigger we assume a magnitude-amplified earthquake positioned below or close to the SE-Sophia Basin. Thus the slide is climatically controlled. References: Mangerud, J., Dokken, T., Hebbeln, D., Heggen, B., Ingolfsson, O., Landvik, J. Y., Mejdahl, V., Svendsen, J. I., Vorren, T. O. (1998). "Fluctuations of the Svalbard-Barents Sea ice sheet during the last 150 000 years." Quaternary Science Reviews 17: 11-42. Winkelmann, D., W. Jokat, F. Niessen, R. Stein, and A. Winkler (2006 a), Age and extent of the Yermak Slide north of Spitsbergen, Arctic Ocean, Geochem. Geophys. Geosyst., 7, Q06007, doi:10.1029/2005GC001130.

  9. Environmental contaminants in arctic foxes (Alopex lagopus) in Svalbard: Relationships with feeding ecology and body condition

    Energy Technology Data Exchange (ETDEWEB)

    Fuglei, E. [Norwegian Polar Institute, Polar Environmental Centre, N-9296 Tromso (Norway)]. E-mail: eva.fuglei@npolar.no; Bustnes, J.O. [Norwegian Institute for Nature Research, Division of Arctic Ecology, Polar Environmental Centre, N-9296 Tromso (Norway); Hop, H. [Norwegian Polar Institute, The Polar Environmental Centre, N-9296 Tromso (Norway); Mork, T. [National Veterinary Institute, Regional Laboratory, N-9292 Tromso (Norway); Bjoernfoth, H. [MTM Research Centre, Department of Natural Sciences, Orebro University, 701 82 Orebro (Sweden); Bavel, B. van [MTM Research Centre, Department of Natural Sciences, Orebro University, 701 82 Orebro (Sweden)

    2007-03-15

    Adipose tissues from 20 arctic foxes (Alopex lagopus) of both sexes from Svalbard were analysed for polybrominated diphenyl ether (PBDE), polychlorinated biphenyl (PCB), p,p'-dichlorodiphenyltrichloroethane (DDE), chlordane, and hexachlorobenzene (HCB) concentrations. Gender (0.43 < p < 0.97) and age (0.15 < p < 0.95) were not significantly related to any of the organohalogen groups. Body condition showed a significant inverse relationship with {sigma}PBDE, {sigma}Chlordane and HCB, suggesting that increased tissue contaminant concentrations are associated with depletion of adipose tissue. The seasonal cyclic storage and mobilisation of adipose tissue, characteristic in Arctic wildlife, may then provide increased input of contaminants to sensitive, vital effect organs. Trophic position was estimated by {delta} {sup 15}N from muscle samples and showed significantly positive relationship with all contaminants, with the exception of HCB concentrations. This indicates that foxes feeding at high trophic levels had higher tissue contaminant levels as a result of bioaccumulation in the food chain. - High contaminant concentrations in the coastal ecotype of arctic fox may cause toxic health effects due to huge annual cyclic variation in storage and mobilisation of adipose tissue.

  10. Norwegian Arctic climate. Climate influencing emissions, scenarios and mitigation options at Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Vestreng, Vigdis; Kallenborn, Roland; Oekstad, Elin

    2010-07-01

    The goal of this study was to establish an emission inventory and emission scenarios for climate influencing compounds at Svalbard, as a basis to develop strategies for emission reduction measures and policies. Emissions for the years 2000-2007 have been estimated for the Svalbard Zone. This area, covering about 173 000 km{sub 2}, ranges from 10 E to 35 E longitude and 74 N to 81 N latitude (Figure 1). In addition, air and ship transport between Tromsoe at the Norwegian mainland and Svalbard has been included. Pollutants considered in our inventory are carbon dioxide (CO{sub 2}), methane (CH{sub 4}), Sulphur dioxide (SO{sub 2}), Nitrogen oxides (NO{sub x} as NO{sub 2}), and for the first time also estimates of black carbon (BC, soot) and organic carbon (OC) have been included. Our results show that emissions of all pollutants have increased over the time span 2000-2007 (Figure 2), and are expected to increase also in the future if additional measures are not implemented (Figure 12). The emissions from Svalbard are minuscule compared to emission released from the Norwegian mainland and waters (1% in the case of CO{sub 2}). Even so, local releases of climate influencing compounds in the vulnerable Arctic may turn out to make a difference both with respect to adverse environmental effects and to climate change. Emissions have been estimated for all activities of any significance taking place at and around Svalbard. Combustion sources as well as fugitive emissions of methane are included. The main sectors are coal mining, energy production and transportation. Pollution from 28 sub sectors related to these activities has been estimated. The scope of this work differs from that covered by national inventories since emission estimates are based on the fuel consumed and include emissions from international shipping and aviation. Fuel consumption data were collected from local authorities, institutions and industry. Emission factors have been selected from relevant

  11. Demographic population structure and fungal associations of plants colonizing High Arctic glacier forelands, Petuniabukta, Svalbard

    Directory of Open Access Journals (Sweden)

    Jakub Těšitel

    2014-04-01

    Full Text Available The development of vegetation in Arctic glacier forelands has been described as unidirectional, non-replacement succession characterized by the gradual establishment of species typical for mature tundra with no species turnover. Our study focused on two early colonizers of High Arctic glacier forelands: Saxifraga oppositifolia (Saxifragaceae and Braya purpurascens (Brassicaceae. While the first species is a common generalist also found in mature old growth tundra communities, the second specializes on disturbed substrate. The demographic population structures of the two study species were investigated along four glacier forelands in Petuniabukta, north Billefjorden, in central Spitsbergen, Svalbard. Young plants of both species occurred exclusively on young substrate, implying that soil conditions are favourable for establishment only before soil crusts develop. We show that while S. oppositifolia persists from pioneer successional stages and is characterized by increased size and flowering, B. purpurascens specializes on disturbed young substrate and does not follow the typical unidirectional, non-replacement succession pattern. Plants at two of the forelands were examined for the presence of root-associated fungi. Fungal genus Olpidium (Fungus incertae sedis was found along a whole successional gradient in one of the forelands.

  12. The impact of a seasonally ice free Arctic Ocean on the climate and surface mass balance of Svalbard

    Directory of Open Access Journals (Sweden)

    J. J. Day

    2011-07-01

    Full Text Available General circulation models (GCMs predict a rapid decrease in Arctic sea ice extent in the 21st century. The decline of September sea ice is expected to continue until the Arctic Ocean is seasonally ice free, leading to a much perturbed Arctic climate with large changes in surface energy flux. Svalbard, located on the present day sea ice edge, contains many low lying ice caps and glaciers which are extremely sensitive to changes in climate. Records of past accumulation indicate that the surface mass balance (SMB of Svalbard is also sensitive to changes in the position of the sea ice edge.

    To investigate the impact of 21st Century sea ice decline on the climate and surface mass balance of Svalbard a high resolution (25 km regional climate model (RCM was forced with a repeating cycle of sea surface temperatures (SSTs and sea ice conditions for the periods 1961–1990 and 2061–2090. By prescribing 20th Century SSTs and 21st Century sea ice for one simulation, the impact of sea ice decline is isolated. This study shows that the coupled impact of sea ice decline and SST increase results in a decrease in SMB, whereas the impact of sea ice decline alone causes an increase in SMB of similar magnitude.

  13. Bacterial diversity in faeces from polar bear (Ursus maritimus in Arctic Svalbard

    Directory of Open Access Journals (Sweden)

    Brusetti Lorenzo

    2010-01-01

    Full Text Available Abstract Background Polar bears (Ursus maritimus are major predators in the Arctic marine ecosystem, feeding mainly on seals, and living closely associated with sea ice. Little is known of their gut microbial ecology and the main purpose of this study was to investigate the microbial diversity in faeces of polar bears in Svalbard, Norway (74-81°N, 10-33°E. In addition the level of blaTEM alleles, encoding ampicillin resistance (ampr were determined. In total, ten samples were collected from ten individual bears, rectum swabs from five individuals in 2004 and faeces samples from five individuals in 2006. Results A 16S rRNA gene clone library was constructed, and all sequences obtained from 161 clones showed affiliation with the phylum Firmicutes, with 160 sequences identified as Clostridiales and one sequence identified as unclassified Firmicutes. The majority of the sequences (70% were affiliated with the genus Clostridium. Aerobic heterotrophic cell counts on chocolate agar ranged between 5.0 × 104 to 1.6 × 106 colony forming units (cfu/ml for the rectum swabs and 4.0 × 103 to 1.0 × 105 cfu/g for the faeces samples. The proportion of ampr bacteria ranged from 0% to 44%. All of 144 randomly selected ampr isolates tested positive for enzymatic β-lactamase activity. Three % of the ampr isolates from the rectal samples yielded positive results when screened for the presence of blaTEM genes by PCR. BlaTEM alleles were also detected by PCR in two out of three total faecal DNA samples from polar bears. Conclusion The bacterial diversity in faeces from polar bears in their natural environment in Svalbard is low compared to other animal species, with all obtained clones affiliating to Firmicutes. Furthermore, only low levels of blaTEM alleles were detected in contrast to their increasing prevalence in some clinical and commensal bacterial populations.

  14. Norwegian Arctic climate. Climate influencing emissions, scenarios and mitigation options at Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Vestreng, Vigdis; Kallenborn, Roland; Oekstad, Elin

    2010-07-01

    The goal of this study was to establish an emission inventory and emission scenarios for climate influencing compounds at Svalbard, as a basis to develop strategies for emission reduction measures and policies. Emissions for the years 2000-2007 have been estimated for the Svalbard Zone. This area, covering about 173 000 km{sub 2}, ranges from 10 E to 35 E longitude and 74 N to 81 N latitude (Figure 1). In addition, air and ship transport between Tromsoe at the Norwegian mainland and Svalbard has been included. Pollutants considered in our inventory are carbon dioxide (CO{sub 2}), methane (CH{sub 4}), Sulphur dioxide (SO{sub 2}), Nitrogen oxides (NO{sub x} as NO{sub 2}), and for the first time also estimates of black carbon (BC, soot) and organic carbon (OC) have been included. Our results show that emissions of all pollutants have increased over the time span 2000-2007 (Figure 2), and are expected to increase also in the future if additional measures are not implemented (Figure 12). The emissions from Svalbard are minuscule compared to emission released from the Norwegian mainland and waters (1% in the case of CO{sub 2}). Even so, local releases of climate influencing compounds in the vulnerable Arctic may turn out to make a difference both with respect to adverse environmental effects and to climate change. Emissions have been estimated for all activities of any significance taking place at and around Svalbard. Combustion sources as well as fugitive emissions of methane are included. The main sectors are coal mining, energy production and transportation. Pollution from 28 sub sectors related to these activities has been estimated. The scope of this work differs from that covered by national inventories since emission estimates are based on the fuel consumed and include emissions from international shipping and aviation. Fuel consumption data were collected from local authorities, institutions and industry. Emission factors have been selected from relevant

  15. Lake-sediment evidence for local and remote sources of atmospherically deposited pollutants on Svalbard

    OpenAIRE

    Rose, Neil L.; Rose, C. L.; Boyle, John F.; Appleby, P.G

    2004-01-01

    Twenty-one lakes along the west coast of Svalbard were cored between 28 July and 14 August 1995. Five cores were 210Pb dated and analysed for spheroidal carbonaceous particles (SCPs), indicators of deposition from fossil-fuel combustion sources, and trace metals. Surface and pre-industrial levels of five cores were analysed for ten polychlorinated biphenyl (PCB) isomers and 16 polycyclic aromatic hydrocarbon (PAH) compounds, whilst all 21 surface sediments were analysed for SCPs. Temporal and...

  16. Variation in bird's originating nitrogen availability limits High Arctic tundra development over last 2000 year (Hornsund, Svalbard)

    Science.gov (United States)

    Skrzypek, Grzegorz; Wojtuń, Bronisław; Hua, Quan; Richter, Dorota; Jakubas, Dariusz; Wojczulanis-Jakubas, Katarzyna; Samecka-Cymerman, Aleksandra

    2016-04-01

    Arctic and subarctic regions play important roles in the global carbon balance. However, nitrogen (N) deficiency is a major constraint for organic carbon sequestration in the High Arctic. Hence, the identification of the relative contributions from different N-sources is critical for understanding the constraints that limit tundra growth. The stable nitrogen composition of the three main N-sources and numerous plants were analyzed in ten tundra types (including those influenced by seabirds) in the Fuglebekken catchment (Hornsund, Svalbard, 77°N 15°E). The percentage of the total tundra N-pool provided by seabirds' feces (from planktivorous colonially breeding little auks Alle alle), ranged from 0-21% in Patterned-ground tundra to 100% in Ornithocoprophilous tundra. The total N-pool utilized by tundra plants in the studied catchment originated from birds (36%), atmospheric deposition (38%), and N2-fixation (26%). The results clearly show that N-pool in the tundra is significantly supplemented by nesting seabirds. Thus, if they experienced climate change induced substantial negative environmental pressure, it would adversely influence the tundra N-budget (Skrzypek et al. 2015). The growth rates and the sediment thickness (bird-N rich tundra with very diverse ages ranging from 235 to 2300 cal BP and thickness up to 110 cm. The growth rates for this tundra (62 cm core, 18 AMS 14C dates) were high (1.5-3.0 mm/yr) between 1568 and 1804 AD and then substantially declined for the period between 1804 and 1929 AD (0.2 mm/yr). These findings deliver an additional argument, that the organic matter accumulation is driven not only directly by climatic conditions but also by birds' contribution to the tundra N-pool. Skrzypek G, Wojtuń B, Richter D, Jakubas D, Wojczulanis-Jakubas K, Samecka-Cymerman A, 2015. Diversification of nitrogen sources in various tundra vegetation types in the high Arctic. PLoS ONE 10(9): e0136536.

  17. The alien terrestrial invertebrate fauna of the High Arctic archipelago of Svalbard: potential implications for the native flora and fauna

    Directory of Open Access Journals (Sweden)

    Stephen J. Coulson

    2015-09-01

    Full Text Available Experience from the Antarctic indicates that the establishment of alien species may have significant negative effects on native flora and fauna in polar regions and is considered to be amongst the greatest threats to biodiversity. But, there have been few similar studies from the Arctic. Although the terrestrial invertebrate inventory of the Svalbard Archipelago is amongst the most complete for any region of the Arctic, no consideration has yet been made of alien terrestrial invertebrate species, their invasiveness tendencies, threat to the native biology or their route of entry. Such baseline information is critical for appropriate management strategies. Fifteen alien invertebrate species have established in the Svalbard environment, many of which have been introduced via imported soils. Biosecurity legislation now prohibits such activities. None of the recorded established aliens yet show invasive tendencies but some may have locally negative effects. Ten species are considered to be vagrants and a further seven are classified as observations. Vagrants and the observations are not believed to be able to establish in the current tundra environment. The high connectivity of Svalbard has facilitated natural dispersal processes and may explain why few alien species are recorded compared to isolated islands in the maritime Antarctic. The vagrant species observed are conspicuous Lepidoptera, implying that less evident vagrant species are also arriving regularly. Projected climate change may enable vagrant species to establish, with results that are difficult to foresee.

  18. On the physical controls of the carbon dioxide balance at a high arctic site in Svalbard

    International Nuclear Information System (INIS)

    Current predictions of the effects of climate change indicate that the Arctic may experience a larger than average increase in temperature with consequent changes to the length of the snow-free active summer period, winter snow depth and amount and frequency of summer precipitation being highly probable. This paper reports on measurements of carbon dioxide flux at a high arctic site at Ny-Aalesund (78o 56' N, 11o 55' E), Svalbard and the physical climate variables that largely control this flux. lt is shown that during three important precipitation-free periods of the active summer period, namely post snow melt, high summer, and early autumn, the net balance between CO2 flux from the soil (due to respiration of roots and soil organisms) and CO2 assimilation by the vegetation is controlled largely by soil temperature and solar radiation. A simple combined photosynthetic assimilation-soil respiration model is shown to be capable of simulating the net CO2 flux during mid-summer, but is less proficient in the post snow melt period and in early autumn when the simple models' inability to simulate the effects of emergent growth and ponding during the former and senescence, freezing temperatures and dew during the latter indicates the need for a more complex descriptive model. The net CO2 flux during the measurement periods progresses from a net CO2 source of 0.3 gC m-2d-1 during late snow melt to a mid summer net CO2 sink of -0.39 gC m-2d-1, returning to a net CO2 source of 0.1 gC m-2d-1 in the early autumn. Simple extrapolation of the data indicates that, during the active summer season in 1995, this site was a net sink of CO2 of approximately -9 gC m-2. (author)

  19. Turbulence and heat flux observations in the Arctic north of Svalbard

    Science.gov (United States)

    Meyer, Amelie; Sundfjord, Arild; Fer, Ilker; Smedsrud, Lars Henrik

    2016-04-01

    Heat fluxes and mixing between the ocean and the sea ice in the Arctic is fundamental to understanding the new first year sea ice regime and consequences for regional and global ocean circulation. Here we present observations collected between January and June 2015 during the Norwegian Young sea Ice (N-ICE2015) campaign in the Arctic Ocean north of Svalbard. In January 2015, the Norwegian research vessel Lance was frozen into the ice at 83o.3N 21.5oE. Oceanographic, atmospheric, sea ice, snow and biological data were collected above, on, and below the ice using R/V Lance as the base for the ice camp that was drifting south towards the Fram Strait. Over the following six months, four different drifts took place in the same area, from the Nansen Basin, through the Marginal Ice Zone, to the open ocean. Throughout the drifts, the oceanography team collected turbulence measurements to estimate mixing, heat, salt, and momentum fluxes in the ice-ocean boundary layer and between the sub-surface warm Atlantic Water layer and the ice-ocean boundary layer close to freezing point. Water tracer data was collected to map water mass properties, and the distribution of the Atlantic Water inflow. Here we present 600 under-ice microstructure profiles spanning five months, from the deep Nansen Basin to the Yermak Plateau. During this period, several large atmospheric storms took place, forcing a fast drift of the ice camp. Tides were weak in the Nansen Basin and strong on the Yermak Plateau. We investigate vertical heat fluxes between the Atlantic Water layer and the surface mixed layer. Variations in mixing and heat fluxes are interpreted in terms of atmospheric forcing and regional topography.

  20. Recent environmental change and atmospheric contamination on Svalbard as recorded in lake sediments – modern limnology, vegetation, and pollen deposition

    OpenAIRE

    Birks, Harry John Betteley; Monteith, Don T.; Rose, Neil L.; Jones, Vivienne J.; Peglar, Sylvia M.

    2004-01-01

    This is the second in a series of nine papers published in this special issue dedicated to recent environmental change on Svalbard. H.J.B. Birks, Vivienne J. Jones, and Neil L. Rose were guest editors of this special issue. Twenty-four lakes on Svalbard were sampled for palaeolimnological studies and are described in terms of their geographical location, catchment characteristics, water chemistry, and flora. No sediment could be retrieved from one of the lakes. There is a close correlation...

  1. The effect of misleading surface temperature estimations on the sensible heat fluxes at a high Arctic site – the Arctic Turbulence Experiment 2006 on Svalbard (ARCTEX-2006

    Directory of Open Access Journals (Sweden)

    J. Lüers

    2010-01-01

    Full Text Available The observed rapid climate warming in the Arctic requires improvements in permafrost and carbon cycle monitoring, accomplished by setting up long-term observation sites with high-quality in-situ measurements of turbulent heat, water and carbon fluxes as well as soil physical parameters in Arctic landscapes. But accurate quantification and well adapted parameterizations of turbulent fluxes in polar environments presents fundamental problems in soil-snow-ice-vegetation-atmosphere interaction studies. One of these problems is the accurate estimation of the surface or aerodynamic temperature T(0 required to force most of the bulk aerodynamic formulae currently used. Results from the Arctic-Turbulence-Experiment (ARCTEX-2006 performed on Svalbard during the winter/spring transition 2006 helped to better understand the physical exchange and transport processes of energy. The existence of an atypical temperature profile close to the surface in the Arctic spring at Svalbard could be proven to be one of the major issues hindering estimation of the appropriate surface temperature. Thus, it is essential to adjust the set-up of measurement systems carefully when applying flux-gradient methods that are commonly used to force atmosphere-ocean/land-ice models. The results of a comparison of different sensible heat-flux parameterizations with direct measurements indicate that the use of a hydrodynamic three-layer temperature-profile model achieves the best fit and reproduces the temporal variability of the surface temperature better than other approaches.

  2. Palynology of two 4500 year old skua-mounds of the Arctic Skua (Stercorarius parasiticus (L.)) in Svalbard

    OpenAIRE

    van der Knaap, W.O.

    1988-01-01

    Skuamounds are peaty hillocks up to 70 cm high used by Arctic Skuas (Stercorarius parasiticus (L.)) for surveying their breeding territory. Well-developed skua-mounds in Svalbard can be considered as small guanogenic bogs', because the peat formation depends on manuring by birds and the water-table in the mound is higher than the surrounding tundra. Peat sections measuring 34 cm and 40 cm from two skuamounds from Edgeøya and Spitsbergen were radiocarbon dated and studied for pollen and spores...

  3. High activity and low temperature optima of extracellular enzymes in Arctic sediments: implications for carbon cycling by heterotrophic microbial communities

    DEFF Research Database (Denmark)

    Arnosti, C.; Jørgensen, BB

    2003-01-01

    The rate of the initial step in microbial remineralization of organic carbon, extracellular enzymatic hydrolysis, was investigated as a function of temperature in permanently cold sediments from 2 fjords on the west coast of Svalbard (Arctic Ocean). We used 4 structurally distinct polysaccharides...... hydrolysis in order to determine the relative temperature responses of the initial and terminal steps in microbial remineralization of carbon. The temperature optimum of sulfate reduction, 21degreesC, was considerably lower than previous reports of sulfate reduction in marine sediments, but is consistent...... with recent studies of psychrophilic sulfate reducers isolated from Svalbard sediments. A calculation of potential carbon flow into the microbial food chain demonstrated that the activity of just one type of polysaccharide-hydrolyzing enzyme could in theory supply 21 to 100% of the carbon consumed via...

  4. The influence of cruise ship emissions on air pollution in Svalbard – a harbinger of a more polluted Arctic?

    Directory of Open Access Journals (Sweden)

    S. Eckhardt

    2013-08-01

    Full Text Available In this study we have analyzed whether tourist cruise ships have an influence on measured sulfur dioxide (SO2, ozone (O3, Aitken mode particle and equivalent black carbon (EBC concentrations at Ny Ålesund and Zeppelin Mountain on Svalbard in the Norwegian Arctic during summer. We separated the measurement data set into periods when ships were present and periods when ships were not present in the Kongsfjord area, according to a long-term record of the number of passengers visiting Ny Ålesund. We show that when ships with more than 50 passengers cruise in the Kongsfjord, measured daytime mean concentrations of 60 nm particles and EBC in summer show enhancements of 72 and 45%, respectively, relative to values when ships are not present. Even larger enhancements of 81 and 72% were found for stagnant conditions. In contrast, O3 concentrations were 5% lower on average and 7% lower under stagnant conditions, due to titration of O3 with the emitted nitric oxide (NO. The differences between the two data subsets are largest for the highest measured percentiles, while relatively small differences were found for the median concentrations, indicating that ship plumes are sampled relatively infrequently even when ships are present although they carry high pollutant concentrations. We estimate that the ships increased the total summer mean concentrations of SO2, 60 nm particles and EBC by 15, 18 and 11%, respectively. Our findings have two important implications. Firstly, even at such a remote Arctic observatory as Zeppelin, the measurements can be influenced by tourist ship emissions. Careful data screening is recommended before summertime Zeppelin data is used for data analysis or for comparison with global chemistry transport models. However, Zeppelin remains as one of the most valuable Arctic observatories, as most other Arctic observatories face even larger local pollution problems. Secondly, given landing statistics of tourist ships on Svalbard, it is

  5. Controls on microalgal community structures in cryoconite holes upon high-Arctic glaciers, Svalbard

    Science.gov (United States)

    Vonnahme, T. R.; Devetter, M.; Žárský, J. D.; Šabacká, M.; Elster, J.

    2016-02-01

    Glaciers are known to harbor surprisingly complex ecosystems. On their surface, distinct cylindrical holes filled with meltwater and sediments are considered hot spots for microbial life. The present paper addresses possible biological interactions within the community of prokaryotic cyanobacteria and eukaryotic microalgae (microalgae) and relations to their potential grazers, such as tardigrades and rotifers, additional to their environmental controls. Svalbard glaciers with substantial allochthonous input of material from local sources reveal high microalgal densities. Small valley glaciers with high sediment coverages and high impact of birds show high biomasses and support a high biological diversity. Invertebrate grazer densities do not show any significant negative correlation with microalgal abundances but rather a positive correlation with eukaryotic microalgae. Shared environmental preferences and a positive effect of grazing are the proposed mechanisms to explain these correlations. Most microalgae found in this study form colonies ( 25 µm), which may protect them against invertebrate grazing. This finding rather indicates grazing as a positive control on eukaryotic microalgae by nutrient recycling. Density differences between the eukaryotic microalgae and prokaryotic cyanobacteria and their high distinction in redundancy (RDA) and principal component (PCA) analyses indicate that these two groups are in strong contrast. Eukaryotic microalgae occurred mainly in unstable cryoconite holes with high sediment loads, high N : P ratios, and a high impact of nutrient input by bird guano, as a proxy for nutrients. In these environments autochthonous nitrogen fixation appears to be negligible. Selective wind transport of Oscillatoriales via soil and dust particles is proposed to explain their dominance in cryoconites further away from the glacier margins. We propose that, for the studied glaciers, nutrient levels related to recycling of limiting nutrients are the

  6. Controls on microalgal community structures in cryoconite holes upon high Arctic glaciers, Svalbard

    Directory of Open Access Journals (Sweden)

    T. R. Vonnahme

    2015-07-01

    Full Text Available Glaciers are known to harbor surprisingly complex ecosystems. On their surface, distinct cylindrical holes filled with meltwater and sediments are considered as hot spots for microbial life. The present paper addresses possible biological interactions within the community of prokaryotic cyanobacteria and eukaryotic microalgae (microalgae and relations to their potential grazers, additional to their environmental controls. Svalbard glaciers with substantial allochthonous input of material from local sources reveal high microalgal densities. Small valley glaciers with high sediment coverages and high impact of birds show high biomasses and support a high biological diversity. Invertebrate grazer densities do not show any significant negative correlation with microalgal abundances, but a positive correlation with eukaryotic microalgae. Most microalgae found in this study form large colonies ( 25 μm, which may protect them against invertebrate grazing. This finding rather indicates grazing as a positive control on eukaryotic microalgae by nutrient recycling. Density differences between the eukaryotic microalgae and prokaryotic cyanobacteria and their high distinction in RDA and PCA analyses indicate that these two groups are in strong contrast. Eukaryotic microalgae occurred mainly in unstable cryoconite holes with high sediment loads, high N : P ratios, and a high impact of bird guano, as a proxy for nutrients. In these environments autochthonous nitrogen fixation appears to be negligible. Selective wind transport of Oscillatoriales via soil and dust particles is proposed to explain their dominance in cryoconites further away from the glacier margins. We propose that, for the studied glaciers, nutrient levels related to recycling of limiting nutrients is the main factor driving variation in the community structure of microalgae and grazers.

  7. Controls on microalgal community structures in cryoconite holes upon high Arctic glaciers, Svalbard

    Science.gov (United States)

    Vonnahme, T. R.; Devetter, M.; Žárský, J. D.; Šabacká, M.; Elster, J.

    2015-07-01

    Glaciers are known to harbor surprisingly complex ecosystems. On their surface, distinct cylindrical holes filled with meltwater and sediments are considered as hot spots for microbial life. The present paper addresses possible biological interactions within the community of prokaryotic cyanobacteria and eukaryotic microalgae (microalgae) and relations to their potential grazers, additional to their environmental controls. Svalbard glaciers with substantial allochthonous input of material from local sources reveal high microalgal densities. Small valley glaciers with high sediment coverages and high impact of birds show high biomasses and support a high biological diversity. Invertebrate grazer densities do not show any significant negative correlation with microalgal abundances, but a positive correlation with eukaryotic microalgae. Most microalgae found in this study form large colonies ( 25 μm), which may protect them against invertebrate grazing. This finding rather indicates grazing as a positive control on eukaryotic microalgae by nutrient recycling. Density differences between the eukaryotic microalgae and prokaryotic cyanobacteria and their high distinction in RDA and PCA analyses indicate that these two groups are in strong contrast. Eukaryotic microalgae occurred mainly in unstable cryoconite holes with high sediment loads, high N : P ratios, and a high impact of bird guano, as a proxy for nutrients. In these environments autochthonous nitrogen fixation appears to be negligible. Selective wind transport of Oscillatoriales via soil and dust particles is proposed to explain their dominance in cryoconites further away from the glacier margins. We propose that, for the studied glaciers, nutrient levels related to recycling of limiting nutrients is the main factor driving variation in the community structure of microalgae and grazers.

  8. Metagabbro associated with the shear zone on Prins Karls Forland (Svalbard, Arctic)

    Science.gov (United States)

    Maraszewska, Maria; Manecki, Maciej; Czerny, Jerzy; Schneider, David; Myhre, Per Inge; Faehnrich, Karol; Barnes, Christopher

    2016-04-01

    Prins Karls Forland (PKF) is a N-S elongated island situated west of Spitsbergen in the Svalbard archipelago, High Arctic. The northern part of the island is dominated by siliciclastic metasediments regionally metamorphosed to greenshist facies assemblages during one distinct stage of tectonism. Amphibolite facies garnet-mica schists, mica schists, quartzites and carbonate-silicate rocks exhibiting evidence of at least two distinct, strong deformation episodes (including mylonitization) locally outcrop on the east coast of PKF, termed the Pinkie Unit. A ~1 km wide shear zone containing ductile to brittle structures and distinct outcrops of greenstones (metagabbros and greenschists), associated with magnetite ore, separates these two contrasting tectonic units. Ten samples of greenstones were collected on the slopes of Lauratzonfjellet and Boureefjellet for petrologic and geochemical analyses. Despite intense localized shearing, the metagabbros are undeformed and preserve coarse crystalline, magmatic texture, which is locally poikilitic. The primary magmatic assemblage consists of brown hornblende, plagioclase, biotite and opaque minerals, with accessory apatite and titanite. No relicts of pyroxenes are preserved. Formation of secondary uralite, sericite and chlorite is observed. Metamorphic assemblage consists of actinolite pseudomorhs after hornblende, epidote, and second generation biotite. Blue amphibole is observed in one sample from Boureefjellet; greenschists from Boureefjellet also contain fibrous blue amphibole, as well as garnets, actinolite, epidote and biotite. Some rocks sampled on Boureefjellet are more strongly deformed and exhibit probably two stages of metamorphism: amphibolite facies metamorphism resulting in blue amphibole-garnet assemblage followed by greenschist facies metamorphism resulting in actinolite-epidote-biotite paragenesis. Parallel and overlapping patterns on chondrite-normalized REE diagrams and spider diagrams indicate that these

  9. Seasonal feeding strategies of Calanus in the high-Arctic Svalbard region

    Science.gov (United States)

    Søreide, Janne E.; Falk-Petersen, Stig; Hegseth, Else Nøst; Hop, Haakon; Carroll, Michael L.; Hobson, Keith A.; Blachowiak-Samolyk, Katarzyna

    2008-10-01

    The feeding strategies of Calanus hyperboreus, C. glacialis, and C. finmarchicus were investigated in the high-Arctic Svalbard region (77-81 °N) in May, August, and December, including seasons with algal blooms, late- to post-bloom situations, and unproductive winter periods. Stable isotope and fatty acid trophic marker (FATM) techniques were employed together to assess trophic level (TL), carbon sources (phytoplankton vs. ice algae), and diet of the three Calanus species. In addition, population development, distribution, and nutritional state (i.e. storage lipids) were examined to estimate their population status at the time of sampling. In May and August, the vertical distribution of the three Calanus species usually coincided with the maximum algal biomass. Their stable isotope and fatty acid (FA) composition indicated that they all were essentially herbivores in May, when the algal biomass was highest. Their FA composition, however, revealed different food preferences. C. hyperboreus had high proportions of 18:4n3, suggesting that it fed mainly on Phaeocystis, whereas C. glacialis and C. finmarchicus had high proportions of 16:4n1, 16:1n7, and 20:5n3, suggesting diatoms as their major food source. Carbon sources (i.e. phytoplankton vs. ice algae) were not possible to determine solely from FATM techniques since ice-diatoms and pelagic-diatoms were characterised by the same FA. However, the enriched δ13C values of C. glacialis and C. finmarchicus in May indicated that they fed both on pelagic- and ice-diatoms. Patterns in absolute FA and fatty alcohol composition revealed that diatoms were the most important food for C. hyperboreus and C. glacialis, followed by Phaeocystis, whereas diatoms, Phaeocystis and other small autotrophic flagellates were equally important food for C. finmarchicus. During periods of lower algal biomass, only C. glacialis exhibited evidence of significant dietary switch, with a TL indicative of omnivory (mean TL=2.4). Large spatial

  10. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability.

    Science.gov (United States)

    Andersen, Martin S; Fuglei, Eva; König, Max; Lipasti, Inka; Pedersen, Åshild Ø; Polder, Anuschka; Yoccoz, Nigel G; Routti, Heli

    2015-04-01

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ13C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p'-DDE, mirex and PBDEs decreased 4-11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ13C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ13C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. PMID:25536177

  11. Terrestrial atmospheric responses on Svalbard to the 20 March 2015 Arctic total solar eclipse under extreme conditions.

    Science.gov (United States)

    Pasachoff, J M; Peñaloza-Murillo, M A; Carter, A L; Roman, M T

    2016-09-28

    This article reports on the near-surface atmospheric response at the High Arctic site of Svalbard, latitude 78° N, as a result of abrupt changes in solar insolation during the 20 March 2015 equinox total solar eclipse and notifies the atmospheric science community of the availability of a rare dataset. Svalbard was central in the path of totality, and had completely clear skies. Measurements of shaded air temperature and atmospheric pressure show only weak, if any, responses to the reduced insolation. A minimum in the air temperature at 1.5 m above the ground occurred starting 2 min following the end of totality, though this drop was only slightly beyond the observed variability for the midday period. Eclipse-produced variations in surface pressure, if present, were less than 0.3 hPa.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. PMID:27550756

  12. Physical properties of the arctic summer aerosol particles in relation to sources at Ny-Alesund, Svalbard

    Indian Academy of Sciences (India)

    C G Deshpande; A K Kamra

    2014-02-01

    Measurements of the number concentration and size distribution of aerosol particles in the size range of 0.5–20 m diameter were made with an aerodynamic particle sizer at an Arctic site at Ny-Alesund, Svalbard in August–September 2007 during the International Polar Year 2007–2008. Data are analyzed to study the aerosol number concentration–wind speed relationships. The sea-salt particles of marine origin generated within the Arctic circle are identified as the main source of the Arctic summer aerosols. Total number concentration of aerosol particles increases with increase in wind speed, the increase being more when winds from open leads over the oceanic sector are reaching the station as compared to when winds from pack ice in other directions are reaching the station. The larger increase with winds from the oceanic sector is attributed to the enhanced bubble-breaking activity and increased entrainment of dimethyl sulphide particles at the sea surface. Although, the increase in total aerosol number concentration associated with the winds from the oceanic sector is spread over the whole range of particle sizes, the increase in coarse mode particles is more prominent than that in the accumulation mode particles. The age of airmass over pack ice is also an important factor to determine the aerosol concentration over the Arctic region. The process of rainout/washout of the aerosol particles due to drizzle/snowfall is an effective sink mechanism in the Arctic environment. The aerosol particle concentration starts decreasing within a few minutes from the start of these events but requires a few hours to restore to the normal background aerosol level after the end of event.

  13. Diversity and Composition of Bacterial Community in Soils and Lake Sediments from an Arctic Lake Area

    Science.gov (United States)

    Wang, Neng Fei; Zhang, Tao; Yang, Xiao; Wang, Shuang; Yu, Yong; Dong, Long Long; Guo, Yu Dong; Ma, Yong Xing; Zang, Jia Ye

    2016-01-01

    This study assessed the diversity and composition of bacterial communities within soils and lake sediments from an Arctic lake area (London Island, Svalbard). A total of 2,987 operational taxonomic units were identified by high-throughput sequencing, targeting bacterial 16S rRNA gene. The samples from four sites (three samples in each site) were significantly different in geochemical properties and bacterial community composition. Proteobacteria and Acidobacteria were abundant phyla in the nine soil samples, whereas Proteobacteria and Bacteroidetes were abundant phyla in the three sediment samples. Furthermore, Actinobacteria, Chlorobi, Chloroflexi, Elusimicrobia, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Proteobacteria significantly varied in their abundance among the four sampling sites. Additionally, members of the dominant genera, such as Clostridium, Luteolibacter, Methylibium, Rhodococcus, and Rhodoplanes, were significantly different in their abundance among the four sampling sites. Besides, distance-based redundancy analysis revealed that pH (p soils and sediments from a lake area in the Arctic harbor a high diversity of bacterial communities, which are influenced by many geochemical factors of Arctic environments.

  14. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability

    International Nuclear Information System (INIS)

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ13C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ13C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ13C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. - Highlights: • POPs were analyzed in the arctic foxes' liver (n = 141) from Svalbard collected in 1997–2013. • PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year. • Concentrations of

  15. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Martin S. [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway); Department of Arctic and Marine Biology, UiT The Arctic University of Norway, NO-9037 Tromsø (Norway); Fuglei, Eva; König, Max [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway); Lipasti, Inka [Department of Biology, University of Eastern Finland, FI-80101 Joensuu (Finland); Pedersen, Åshild Ø. [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway); Polder, Anuschka [Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås (Norway); Yoccoz, Nigel G. [Department of Arctic and Marine Biology, UiT The Arctic University of Norway, NO-9037 Tromsø (Norway); Routti, Heli, E-mail: heli.routti@npolar.no [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway)

    2015-04-01

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ{sup 13}C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ{sup 13}C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ{sup 13}C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. - Highlights: • POPs were analyzed in the arctic foxes' liver (n = 141) from Svalbard collected in 1997–2013. • PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year.

  16. Community structure, cellular rRNA content, and activity of sulfate-reducing bacteria in marine Arctic sediments

    DEFF Research Database (Denmark)

    Ravenschlag, K.; Sahm, K.; Knoblauch, C.;

    2000-01-01

    The community structure of sulfate-reducing bacteria (SRB) of a marine Arctic sediment (Smeerenburg-fjorden, Svalbard) a-as characterized by both fluorescence in situ hybridization (FISH) and rRNA slot blot hybridization by using group- and genus-specific 16S rRNA-targeted oligonucleotide probes......, The SRB community was dominated by members of the Desulfosarcina-Desulfococcus group. This group accounted for up to 73% of the SRB detected and up to 70% of the SRB rRNA detected. The predominance was shown to be a common feature for different stations along the coast of Svalbard, In a top......-Desulfococcus group. A group of clone sequences (group SVAL1) most closely related to Desulfosarcina variabilis (91.2% sequence similarity) was dominant and was shown to be most abundant in situ, accounting for up to 54.8% of the total SRB detected. A comparison of the two methods used for quantification showed...

  17. Diversity and Distribution of Aquatic Fungal Communities in the Ny-Ålesund Region, Svalbard (High Arctic) : Aquatic Fungi in the Arctic.

    Science.gov (United States)

    Zhang, Tao; Wang, Neng-Fei; Zhang, Yu-Qin; Liu, Hong-Yu; Yu, Li-Yan

    2016-04-01

    We assessed the diversity and distribution of fungi in 13 water samples collected from four aquatic environments (stream, pond, melting ice water, and estuary) in the Ny-Ålesund Region, Svalbard (High Arctic) using 454 pyrosequencing with fungi-specific primers targeting the internal transcribed spacer (ITS) region of the ribosomal rRNA gene. Aquatic fungal communities in this region showed high diversity, with a total of 43,061 reads belonging to 641 operational taxonomic units (OTUs) being found. Of these OTUs, 200 belonged to Ascomycota, 196 to Chytridiomycota, 120 to Basidiomycota, 13 to Glomeromycota, and 10 to early diverging fungal lineages (traditional Zygomycota), whereas 102 belonged to unknown fungi. The major orders were Helotiales, Eurotiales, and Pleosporales in Ascomycota; Chytridiales and Rhizophydiales in Chytridiomycota; and Leucosporidiales and Sporidiobolales in Basidiomycota. The common fungal genera Penicillium, Rhodotorula, Epicoccum, Glaciozyma, Holtermanniella, Betamyces, and Phoma were identified. Interestingly, the four aquatic environments in this region harbored different aquatic fungal communities. Salinity, conductivity, and temperature were important factors in determining the aquatic fungal diversity and community composition. The results suggest the presence of diverse fungal communities and a considerable number of potentially novel fungal species in Arctic aquatic environments, which can provide reliable data for studying the ecological and evolutionary responses of fungi to climate change in the Arctic ecosystem. PMID:26492897

  18. Long term trends of CCN concentration in Arctic region at Zeppelin station, Ny-Ålesund, Svalbard

    Science.gov (United States)

    Jung, C. H.; Yoon, Y. J.; Kang, H. J.; Gim, Y. T.; Lee, B. Y.; Ström, J.; Krejci, R.; Tunved, P.

    2015-12-01

    The Arctic is a challenging region when assessing aerosol impacts due to their large variations in concentration, and varying chemical, physical and optical properties. In the climate effects of atmosphere aerosol indirect force, cloud condensation nuclei (CCN) play an important role because particles acting as they can grow to cloud droplets by condensation of water vapor, affecting cloud properties in various ways. For example, the increased CCN concentrations lead to the production of more numerous and smaller cloud drops, which can result in optically thicker clouds that tend to reflect more incoming solar radiation back to space (Twomey, 1977). Thus, investigating the physical process of the CCN aerosol that controls cloud droplet formation is important in understanding the radiative transfer and climate effect. In addition, there are still large variabilities in Arctic CCN number concentrations remaining. These variabilities are mainly due to the result of varying aerosol sources and chemical composition (Browse et al., 2012). Especially, the analysis on the long term trends as well as seasonality of CCN and relation with aerosols are very rare and need to be investigated. In this study, CCN concentration data collected at the Zeppelin observatory located on the top of Mt. Zeppelin, Svalbard (78° 54' N, 11° 53' E) are analyzed during 2007-2013. The seasonal and yearly trends of CCN in the Arctic region during the long periods are presented. The obtained results are compared with other instrumental data such as aerosol size distribution and total number concentration. ReferenceBrowse, J., Carslaw, K. S., Arnold, S. R., Pringle, K., and Boucher, O, 2012, The scavenging processes controlling the seasonal cycle in Arctic sulphate and black carbon aerosol, Atmos. Chem. Phys., 12, 6775-6798. Twomey, S., 1977: Atmospheric Aerosols. Elsevier.

  19. Microbial community development on the surface of Hans and Werenskiold Glaciers (Svalbard, Arctic): a comparison

    OpenAIRE

    Grzesiak, Jakub; Górniak, Dorota; Świątecki, Aleksander; Aleksandrzak-Piekarczyk, Tamara; Szatraj, Katarzyna; Zdanowski, Marek K.

    2015-01-01

    Surface ice and cryoconite holes of two types of polythermal Svalbard Glaciers (Hans Glacier—grounded tidewater glacier and Werenskiold Glacier—land-based valley glacier) were investigated in terms of chemical composition, microbial abundance and diversity. Gathered data served to describe supraglacial habitats and to compare microbe–environment interactions on those different type glaciers. Hans Glacier samples displayed elevated nutrient levels (DOC, nitrogen and seston) compared to Werensk...

  20. Biomagnification of mercury in selected species from an Arctic marine food web in Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, Iris, E-mail: iris@akvaplan.niva.no [Norwegian Polar Institute, N-9296 Tromso (Norway); University of Tromso, Institute of Biology, N-9037 Tromso (Norway); Hop, Haakon; Gabrielsen, Geir W. [Norwegian Polar Institute, N-9296 Tromso (Norway)

    2009-08-01

    Concentrations and biomagnification of total mercury (TotHg) and methyl mercury (MeHg) were studied in selected species from the pelagic food web in Kongsfjorden, Svalbard. Twelve species of zooplankton, fish and seabirds, were sampled representing a gradient of trophic positions in the Svalbard marine food web. TotHg and MeHg were analysed in liver, muscle and/or whole specimens. The present study is the first to provide MeHg levels in seabirds from the Svalbard area. The relative MeHg levels decreased with increasing levels of TotHg in seabird tissues. Stable isotopes of nitrogen ({delta}{sup 15}N) were used to determine the trophic levels and the rate of biomagnification of mercury in the food web. A linear relationship between mercury levels and trophic position was found for all seabird species combined and their trophic level, but there was no relationship within species. Biomagnification factors were all > 1 for both TotHg and MeHg, indicating biomagnification from prey to predator. TotHg levels in the different seabirds were similar to levels detected in the Kongsfjorden area in the 1990s.

  1. Biomagnification of mercury in selected species from an Arctic marine food web in Svalbard.

    Science.gov (United States)

    Jaeger, Iris; Hop, Haakon; Gabrielsen, Geir W

    2009-08-01

    Concentrations and biomagnification of total mercury (TotHg) and methyl mercury (MeHg) were studied in selected species from the pelagic food web in Kongsfjorden, Svalbard. Twelve species of zooplankton, fish and seabirds, were sampled representing a gradient of trophic positions in the Svalbard marine food web. TotHg and MeHg were analysed in liver, muscle and/or whole specimens. The present study is the first to provide MeHg levels in seabirds from the Svalbard area. The relative MeHg levels decreased with increasing levels of TotHg in seabird tissues. Stable isotopes of nitrogen (delta(15)N) were used to determine the trophic levels and the rate of biomagnification of mercury in the food web. A linear relationship between mercury levels and trophic position was found for all seabird species combined and their trophic level, but there was no relationship within species. Biomagnification factors were all >1 for both TotHg and MeHg, indicating biomagnification from prey to predator. TotHg levels in the different seabirds were similar to levels detected in the Kongsfjorden area in the 1990s. PMID:19454364

  2. Biomagnification of mercury in selected species from an Arctic marine food web in Svalbard

    International Nuclear Information System (INIS)

    Concentrations and biomagnification of total mercury (TotHg) and methyl mercury (MeHg) were studied in selected species from the pelagic food web in Kongsfjorden, Svalbard. Twelve species of zooplankton, fish and seabirds, were sampled representing a gradient of trophic positions in the Svalbard marine food web. TotHg and MeHg were analysed in liver, muscle and/or whole specimens. The present study is the first to provide MeHg levels in seabirds from the Svalbard area. The relative MeHg levels decreased with increasing levels of TotHg in seabird tissues. Stable isotopes of nitrogen (δ15N) were used to determine the trophic levels and the rate of biomagnification of mercury in the food web. A linear relationship between mercury levels and trophic position was found for all seabird species combined and their trophic level, but there was no relationship within species. Biomagnification factors were all > 1 for both TotHg and MeHg, indicating biomagnification from prey to predator. TotHg levels in the different seabirds were similar to levels detected in the Kongsfjorden area in the 1990s.

  3. Annual CO2 budget and seasonal CO2 exchange signals at a High Arctic permafrost site on Spitsbergen, Svalbard archipelago

    Science.gov (United States)

    Lüers, J.; Westermann, S.; Piel, K.; Boike, J.

    2014-01-01

    The annual variability of CO2 exchange in most ecosystems is primarily driven by the activities of plants and soil microorganisms. However, little is known about the carbon balance and its controlling factors outside the growing season in arctic regions dominated by soil freeze/thaw-processes, long-lasting snow cover, and several months of darkness. This study presents a complete annual cycle of the CO2 net ecosystem exchange (NEE) dynamics for a High Arctic tundra area on the west coast of Svalbard based on eddy-covariance flux measurements. The annual cumulative CO2 budget is close to zero grams carbon per square meter per year, but shows a very strong seasonal variability. Four major CO2 exchange seasons have been identified. (1) During summer (ground snow-free), the CO2 exchange occurs mainly as a result of biological activity, with a predominance of strong CO2 assimilation by the ecosystem. (2) The autumn (ground snow-free or partly snow-covered) is dominated by CO2 respiration as a result of biological activity. (3) In winter and spring (ground snow-covered), low but persistent CO2 release occur, overlain by considerable CO2 exchange events in both directions associated with changes of air masses and air and atmospheric CO2 pressure. (4) The snow melt season (pattern of snow-free and snow-covered areas), where both, meteorological and biological forcing, resulting in a visible carbon uptake by the high arctic ecosystem. Data related to this article are archived under: http://doi.pangaea.de/10.1594/PANGAEA.809507.

  4. Regime shifts in the Arctic North Atlantic during the Neoglacial revealed by seabirds and precipitation isotopes on Bjørnøya, Svalbard

    Science.gov (United States)

    D'Andrea, William J.; Hormes, Anne; Bakke, Jostein; Nicolaisen, Line

    2016-04-01

    The northeastern North Atlantic Ocean, and the Norwegian and Greenland Seas are subject to large hydrographic changes. These variations can influence oceanic heat transport to the Arctic, meridional overturning circulation, and atmospheric circulation patterns and thereby impact global climate patterns. Marine records suggest that numerous large-scale changes in the hydrography of the northern North Atlantic took place during the middle to late Holocene. We report a record of nitrogen and hydrogen isotope measurements from a lake sediment core from Bjørnøya, Svalbard (74.38°N, 19.02°E) that documents major regime shifts in the climate of the northern North Atlantic during the past 6,000 years. Bjørnøya is the nesting ground for one of the largest seabird populations in the North Atlantic. As top predators in the marine ecosystem, seabirds (and their guano) are enriched in 15N; during spring and summer months they deliver isotopically enriched nitrogen to nesting areas. We developed a record of seabird population changes on Bjørnøya based on the nitrogen isotope composition of sediments in a core collected from lake Ellasjøen. The record reveals multiple multicentennial scale changes in δ15N values (varying between ~8-12‰) that track past changes in the size of seabird populations. From the same sediment core, we also developed a record of δD of precipitation, using δD values of sedimentary n-alkanes. Past intervals with the largest inferred bird populations correspond with the most enriched δD of precipitation, which we interpret to represent a more Atlantic climate. Periods with reduced seabird populations correspond with intervals with more negative δD of precipitation and representing a more Arctic climate. Together, the nitrogen and hydrogen isotope records signify regime shifts in the oceanography, marine ecosystem, and atmospheric circulation of the northern North Atlantic that are related to variations in the strength of the subpolar gyre.

  5. NOx during ozone depletion events in the arctic troposphere at Ny-Ålesund, Svalbard

    OpenAIRE

    Beine, Harald J.; Jaffe, Daniel A.; Stordal, Frode; Engardt, Magnuz; Solberg, Sverre; Schmidbauer, Norbert; Holmén, Kim

    2011-01-01

    Measurements of NOx, ozone, non-methane hydrocarbons (NMHC), and other atmospheric constituents were made at the Zeppelin-mountain atmospheric monitoring station near Ny-Ålesund, Svalbard, during the spring of 1994. On a few occasions, we observed tropospheric ozone depletion events with minimum ozone mixing ratios of 3.9 ppbv that lasted for up to 2 days. This paper presents the first measurements of NOx during ozone depletion events. The objective of this work is to explore the role of NOx ...

  6. Cold season soil respiration in response to grazing and warming in the High Arctic Svalbard

    DEFF Research Database (Denmark)

    Strebel, Ditte; Elberling, Bo; Morgner, Elke;

    2010-01-01

    The influence of goose grazing intensity and open-topped chambers (OTCs) on near-surface quantities and qualities of soil organic carbon (SOC) was evaluated in wet and mesic ecosystems in Svalbard. This study followed up a field experiment carried out in 2003-05 (part of the project Fragility of......) and solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. Results reveal variations in soil carbon cycling, with significant seasonal trends controlled by temperature, water content and snow. Experimental warming (OTCs) increased near-surface temperatures in the growing season, resulting in...

  7. Relationship of cyanobacterial and algal assemblages with vegetation in the high Arctic tundra (West Spitsbergen, Svalbard Archipelago

    Directory of Open Access Journals (Sweden)

    Richter Dorota

    2015-09-01

    Full Text Available The paper presents the results of a study of cyanobacteria and green algae assemblages occurring in various tundra types determined on the basis of mosses and vascular plants and habitat conditions. The research was carried out during summer in the years 2009-2013 on the north sea-coast of Hornsund fjord (West Spitsbergen, Svalbard Archipelago. 58 sites were studied in various tundra types differing in composition of vascular plants, mosses and in trophy and humidity. 141 cyanobacteria and green algae were noted in the research area in total. Cyanobacteria and green algae flora is a significant element of many tundra types and sometimes even dominate there. Despite its importance, it has not been hitherto taken into account in the description and classification of tundra. The aim of the present study was to demonstrate the legitimacy of using phycoflora in supplementing the descriptions of hitherto described tundra and distinguishing new tundra types. Numeric hierarchical-accumulative classification (MVSP 3.1 software methods were used to analyze the cyanobacterial and algal assemblages and their co-relations with particular tundra types. The analysis determined dominant and distinctive species in the communities in concordance with ecologically diverse types of tundra. The results show the importance of these organisms in the composition of the vegetation of tundra types and their role in the ecosystems of this part of the Arctic.

  8. Current knowledge of the Tardigrada of Svalbard with the first records of water bears from Nordaustlandet (High Arctic

    Directory of Open Access Journals (Sweden)

    Krzysztof Zawierucha

    2013-11-01

    Full Text Available The first investigations of the tardigrades of Svalbard took place in the early 20th century and 30 papers on the subject have been published to date. In this article, we summarize available information on the distribution of tardigrades in this Arctic archipelago with remarks on the dubious species and records. Additionally, we examined 28 new moss, lichen and soil samples collected from the islands of Nordaustlandet, Edgeøya and Prins Karls Forland. These samples yielded 324 specimens, 15 exuvia and 132 free-laid eggs belonging to 16 limnoterrestrial species (Heterotardigrada and Eutardigrada. These include five first records of water bears from Nordaustlandet, eight new records for Edgeøya and four for Prince Karls Forland. The most dense population of tardigrades was found in a sample with 253 specimens/10 g of dry material and the least dense population in a sample with three specimens/10 g of dry material. The most frequently recorded species in samples collected in this study were Testechiniscus spitsbergensis Scourfield, 1897, Macrobiotus harmsworthi harmsworthi Murray, 1907, and M. islandicus islandicus Richters, 1904. This article also provides the first ever scanning electron microscope photomicrographs of Tenuibiotus voronkovi Tumanov, 2007.

  9. Archaea in Arctic Thermokarst Lake Sediments

    Science.gov (United States)

    Matheus Carnevali, P. B.; Rohrssen, M.; Dodsworth, J. A.; Kuhn, E.; Williams, M.; Adams, H. E.; Berisford, D. F.; Hand, K. P.; Priscu, J. C.; Walter Anthony, K.; Love, G. D.; Hedlund, B. P.; Murray, A. E.

    2011-12-01

    , which include, in part, a methanogenic community. These findings suggest that the archaeal community in lake sediments of the Northern Slope of Alaska may be more relevant to estimates of methane release from the Arctic than previously thought. Our work will set the grounds to further the understanding of the effect of temperature increases on microbial activities that directly affect the greenhouse gas inventory, and it will expand the census of psychrophiles that thrive in permafrost environments.

  10. delta C-13 Analysis of Mars Analog Carbonates Using Evolved Gas Cavity - Ringdown Spectrometry on the 2010 Arctic Mars Analog Svalbard Expedition (AMASE)

    Science.gov (United States)

    Stern, J. C.; McAdam, A. C.; ten Kate, I. L.; Mahaffy, P. R.; Steele, A.; Amundson, H. E. F.

    2011-01-01

    The 2010 Arctic Mars Analog Svalbard Expedition (AMASE) investigated two distinct geologic settings on Svalbard, using instrumentation and techniques in development for future Mars missions, such as the Mars Science Laboratory (MSL), ExoMars, and Mars Sample Return (MSR). The Sample Analysis at Mars (SAM) instrument suite, which will fly on MSL, was developed at Goddard Space Flight Center (GSFC), together with several partners. SAM consists of a quadrupole mass spectrometer (QMS), a gas chromatograph CGC), and a tunable laser spectrometer (TLS), which all analyze gases created by evolved gas analysis (EGA). The two sites studied represent "biotic" and "abiotic" analogs; the "biotic" site being the Knorringfjell fossil methane seep, and the "abiotic" site being the basaltic Sigurdfjell vent complex. The data presented here represent experiments to measure the carbon isotopic composition of carbonates from these two analogs using evolved gas analysis coupled with a commercial cavity ringdown CO2 isotopic analyzer (Picarro) as a proxy for the TLS on SAM.

  11. Some of the dominant cyanobacteria and algae populating the aquatic and hydro-terrestrial habitats of Petuniabukta Bay in Svalbard in the Arctic

    International Nuclear Information System (INIS)

    This is fycologic research of the Svalbard, which is a summary term for all islands situated between 10 grad to 30 grad E and 74 grad to 81 grad latitude in the European part of the Arctic. Three selected sites within the bay Petuniabukta (78 grad 40' NL, 16 grad 27' E) at the end of the Gulf Billefjorden, located in the central part of the largest island of Svalbard were studied. Collection took place in June 2011 and we recorded totally more than 40 kinds of algae and cyanobacteria. Algae were the most abundant species. From cyanobacteria there was a predominance of filamentous Phormidium autumnale, from algae the representatives of genera Monoraphidium sp. div. and Scenedesmus sp. div. These are only partial results as a part of a more wider conceived research of these phototrophic micro-organisms in this area. (authors)

  12. Teachers, Researchers, and Students Collaborating in Arctic Climate Change Research: The Partnership Between the Svalbard REU and ARCUS PolarTREC programs

    Science.gov (United States)

    Roof, S.; Warburton, J.; Oddo, B.; Kane, M.

    2007-12-01

    Since 2004, the Arctic Research Consortium of the U.S. (ARCUS) "TREC" program (Teachers and Researchers Exploring and Collaborating, now "PolarTREC") has sent four K-12 teachers to Svalbard, Norway to work alongside researchers and undergraduate students conducting climate change research as part of the Svalbard Research Experiences for Undergraduates (REU) Program. The benefits of this scientist/educator/student partnership are many. Researchers benefit from teacher participation as it increases their understanding of student learning and the roles and responsibilities of K-12 teachers. The TREC teacher contributes to the research by making observations, analyzing data, and carrying heavy loads of equipment. In collaborating with K- 12 teachers, undergraduate student participants discover the importance of teamwork in science and the need for effective communication of scientific results to a broad audience. The questions that K-12 teachers ask require the scientists and students in our program to explain their work in terms that non-specialists can understand and appreciate. The K-12 teacher provides a positive career role model and several Svalbard REU undergraduate students have pursued K-12 teaching careers after graduating. TREC teachers benefit from working alongside the researchers and by experiencing the adventures of real scientific research in a remote arctic environment. They return to their schools with a heightened status that allows them to share the excitement and importance of scientific research with their students. Together, all parties contribute to greatly enhance public outreach. With ARCUS logistical support, TREC teachers and researchers do live web conferences from the field, reaching hundreds of students and dozens of school administrators and even local politicians. Teachers maintain web journals, describing the daily activities and progress of the researcher team. Online readers from around the world write in to ask questions, which the

  13. Recent transformations in the high-Arctic glacier landsystem Hørbyebreen, Svalbard.

    Science.gov (United States)

    Ewertowski, Marek; Evans, David; Roberts, David; Tomczyk, Aleksandra

    2016-04-01

    representative landsystem model for terrestrial-terminating Svalbard glaciers. The research was founded by Polish National Science Centre (project granted by decision number DEC-2011/01/D/ST10/06494).

  14. Recent transformations in the high-Arctic glacier landsystems based on examples from Svalbard

    Science.gov (United States)

    Ewertowski, Marek; Tomczyk, Aleksandra

    2014-05-01

    Glacier recession and landform development in the foreland of several Svalbard's glaciers were quantified for different spatio-temporal scales. Time-series orthophotos and digital elevation models from 1961, 1990 and 2009 (with ground resolution varying from 0.4 m to 0.7 m) were used for quantification of decadal changes for the whole glacial catchments. Time-series geomorphological maps were constructed using a combination of DEM visualization and stereoscopic viewing of aerial photographs. Planar transformations of landforms were quantified based on orthophotomaps, whereas changes of the volume of ice and landforms were assessed by creation of digital elevation models of differences (i.e. elevation changes between sequential DEMs). Repetitive geomorphological and geodetic field surveys were applied to estimates seasonal and inter-seasonal transformations of various landforms assemblages and individual landforms. Research were carried out for several glaciers in the central part of the Spitsbergen Island, including: Nordenskiöldbreen, Ebbabreen, Raganrbreen, Hørbyebreen, Cambridgebreen, Balliolbreen, Svenbreen and Ferdinandbreen. In the period LIA-2013, glaciers' margins retreated seriously, moreover ice volume and glaciers' surface profiles changed enormously emphasizing the relative importance of glaciers' thinning over area loss. In terms of landscape alteration, the landforms response was much more varied between glaciers. Most important transformation included: (1) developing of a terminoglacial and/or supraglacial lakes, which acted as a sedimentary trap and at the same time probably accelerated glacier erosion, (2) developing the lateral moraines whose transformations were divided into creation, initial, mature, and senile phases, with various magnitudes of debris flow and backwasting activity that changed with time (3) developing of end moraine complexes, which are now the most stable components, alternated mainly by dead-ice downwasting and to a lesser

  15. Organic Pollution in Surface Waters from the Fuglebekken Basin in Svalbard, Norwegian Arctic

    Directory of Open Access Journals (Sweden)

    Jacek Namieśnik

    2011-09-01

    Full Text Available The Fuglebekken basin is situated in the southern part of the island of Spitsbergen (Norwegian Arctic, on the Hornsund fjord (Wedel Jarlsberg Land. Surface water was collected from 24 tributaries (B1–B24 and from the main stream water in the Fuglebekken basin (25 between 10 July 2009 and 30 July 2009. The present investigation reveals the results of the analysis of these samples for their PAH and PCB content. Twelve of 16 PAHs and seven PCBs were determined in the surface waters from 24 tributaries and the main stream. Total PAH and PCB concentrations in the surface waters ranged from 4 to 600 ng/L and from 2 to 400 ng/L respectively. The highest concentrations of an individual PCB (138–308 ng/L and 123 ng/L were found in samples from tributaries B9 and B5. The presence in the basin (thousands of kilometres distant from industrial centres of PAHs and PCBs is testimony to the fact that these compounds are transported over vast distances with air masses and deposited in regions devoid of any human pressure.

  16. Dolerites of Svalbard, north-west Barents Sea Shelf: age, tectonic setting and significance for geotectonic interpretation of the High-Arctic Large Igneous Province

    Directory of Open Access Journals (Sweden)

    Zoltán Pécskay

    2011-08-01

    Full Text Available The dolerites of Svalbard are mineralogically and geochemically homogeneous with geochemical features typical of continental within-plate tholeiites. Their geochemistry is similar to tholeiites belonging to a bimodal suite defined as the High-Arctic Large Igneous Province (HALIP. K–Ar dating of numerous dolerites sampled from many locations across Svalbard define a narrow time span of this magmatism from 125.5±3.6 to 78.3±2.6 Mya. Discrete peaks of intensive activity occurred at 115.3, 100.8, 91.3 and 78.5 Mya corresponding to (1 breakup of the continental crust and formation of an initial rift as a result of mantle plume activity, located in the southern part of the Alpha Ridge; (2 magmatic activity related to spreading along the Alpha Ridge that led to the development of the initial oceanic crust and (3 continuation of spreading along the Alpha Ridge and termination of magmatic activity related to HALIP (last two peaks at 91.3 and 78.5 Mya.

  17. Key conclusions of the Svalbard Shoreline Experiment

    International Nuclear Information System (INIS)

    Major conclusions reached from the Svalbard Field Trials are discussed. In general, the field trials are considered to have been successful as meaningful differences in oil concentration between plots and treatments were quantitatively demonstrated and measured. Some of the major findings of the study are: (1) mechanical relocation of oil sediments significantly accelerated the rate of oil removal; (2) sediment relocation did not elevate toxicity in the near-shore environment to unacceptable levels; (3) changes in oil loading of surface sediments in the upper inter-tidal zone were not sufficient to support mixing (tilling) of the oiled layer as viable for operational use; (4) initial oil removal in this environment was relatively rapid; (5) biodegradation did occur in the Arctic environment and was stimulated by the addition of fertilizer; and (6( microscopic observation and image analysis confirmed that the formation of oil-mineral aggregates facilitated the removal of oil from the beaches

  18. Heterotopisk Svalbard-krim

    OpenAIRE

    Lisbeth Pettersen Wærp

    2015-01-01

    Published version. Source at http://dx.doi.org/10.7557/13.3426. How is the Arctic represented in modern crime fiction written by a female glaciologist, meterologist and polar explorer? Monica Kristensen is the author of a new, critically acclaimed, series of crime novels set in Svalbard. The first four novels of the series are Hollendergraven (2007, The Dutchman's Grave), Kullunge (2008, Coal Baby), Operasjon Fritham (2009, Operation Fritham), Den døde i Barentsburg (2011, The Dead Man in ...

  19. Glaciomarine sedimentation and bottom current activity on the north-western and northern continental margins of Svalbard during the late Quaternary

    Science.gov (United States)

    Chauhan, Teena; Noormets, Riko; Rasmussen, Tine L.

    2016-04-01

    Palaeo-bottom current strength of the West Spitsbergen Current (WSC) and the influence of the Svalbard-Barents Sea Ice Sheet (SBIS) on the depositional environment along the northern Svalbard margins are poorly known. Two gravity cores from the southern Yermak Plateau and the upper slope north of Nordaustlandet, covering marine isotope stage (MIS) 1 to MIS 5, are investigated. Five lithofacies, based on grain size distribution, silt/clay ratio, content and mean of sortable silt (SS), are distinguished to characterise the contourite-dominated sedimentary environments. In addition, depositional environments are described using total organic carbon (TOC), total sulphur (TS) and calcium carbonate (CaCO3) contents of sediments. Facies A, containing coarse SS, suggests strong bottom current activity and good bottom water ventilation conditions as inferred from low TOC content. This facies was deposited during the glacial periods MIS 4, MIS 2 and during the late Holocene. Facies B is dominated by fine SS indicating weak bottom current and poor ventilation (cf. high TOC content of 1.2-1.6%), and correlates with the MIS 4/3 and MIS 2/1 transition periods. With an equal amount of clay and sand, fine SS and high content of TOC, facies C indicates reduced bottom current strength for intervals with sediment supply from proximal sources such as icebergs, sea ice or meltwater discharge. This facies was deposited during the last glacial maximum. Facies D represents mass-flow deposits on the northern Svalbard margin attributed to the SBIS advance at or near the shelf edge. Facies E sediments indicating moderate bottom current strength were deposited during MIS 5 and MIS 3, and during parts of MIS 2. This first late Quaternary proxy record of the WSC flow and sedimentation history from the northern Svalbard margin suggests that the oceanographic conditions and ice sheet processes have exerted first-order control on sediment properties.

  20. Arctic River Discharge and Sediment Loads --- an Overview

    Science.gov (United States)

    Syvitski, J. P.; Overeem, I.; Brakenridge, G. R.; Hudson, B.; Cohen, S.

    2014-12-01

    Evidence suggests that river discharge has been increasing (+10%) over the last 30 years (1977-2007) for most arctic rivers. The peak melt month occurs earlier in the season in 66% of the studied rivers. Cold season flow is also increasing. Satellite discharge estimates, daily, based on microwave radiometry, are now possible from 1998 onwards. Daily river discharge hindcasts over the last 60 years using the water balance model WBMsed at a 10km spatial resolution are now available. The WBMsed model can be used in forecast mode assuming valid input climatology. The challenge here has been the accuracy of sub-polar precipitation grids. While each of these three methods (gauging, orbital sensing, modeling) has temporal and spatial coverage limitations, the combination of all three methods provides for a realistic way forward for estimating local discharge across the pan arctic. Flood inundation products are routinely produced for the pan-arctic using automated mapping algorithms developed by the Dartmouth Flood Observatory. The determination of artic river sediment loads is less than ideal. Some rivers have only been monitored for a short number of years, and many have not been monitored at all. The WBMsed model is perhaps the best method of estimating the daily sediment flux to the Arctic Ocean, at least for rivers where the mean discharge is greater than 30 m3/s. Additionally there is limited-duration field monitoring by national surveys. New methods are being explored, including back calculating the delivery of sediment to the coastal ocean by plume dimensions observed from space (MODIS, LandSat). These methods have had moderate success when applied to plumes extending in the Greenland fjords. Canada maintains an active circa 7-y satellite program (ArcticNet) to track the Mackenzie discharge during the spring-summer runoff period when turbid river water is apt to flow under and over marginal sea ice in the Beaufort Sea.

  1. Late Weichselian and Holocene paleoceanography of Storfjordrenna, southern Svalbard

    Directory of Open Access Journals (Sweden)

    M. Łącka

    2014-08-01

    Full Text Available Multiproxy analyses (incl. benthic and planktonic foraminifera, δ18O and δ13C records, grain-size distribution, ice-rafted debris, XRF geochemistry and magnetic susceptibility were performed on a 14C dated marine sediment core from Storfjordrenna, off southern Svalbard. The sediments in the core cover the termination of Bølling–Allerød, the Younger Dryas and the Holocene, and they reflect general changes in the hydrology/climate of the European Arctic after the last glaciation. Grounded ice of the last Svalbard- Barents Sea Ice Sheet retreated from the coring site ca. 13 850 cal yr BP. During the transition from the sub-glacial to glacimarine setting, Arctic Waters dominated the hydrography in Storfjordrenna. However, the waters were not uniformly cold and experienced several warmer spells. A progressive warming and marked change in the nature of hydrology occurred during the early Holocene. Relatively warm and saline Atlantic Water started to dominate the hydrography from approx. 9500 cal yr BP. Even though the climate in eastern Svalbard was milder at that time than at present (smaller glaciers, there were two slight coolings observed in the periods of 9000–8000 cal yr BP and 6000–5500 cal yr BP. A change of the Storfjordrenna hydrology occurred at the beginning of late Holocene synchronously with glacier growth on land and enhanced bottom current velocities. Although cooling was observed in the surface water, Atlantic Water remained present in the deeper part of water column of Storfjordrenna.

  2. Sediment-Laden sea ice in the Arctic Ocean: Implications for climate, environment and sedimentation

    International Nuclear Information System (INIS)

    Sediments in sea ice were first described by F. Nansen during his famous Fram expedition (1893-1896). Many researchers observed and recorded sediment-laden or dirty sea ice in the Central Arctic, but the origin and incorporation mechanisms are poorly understood and were never the object of detailed studies. Sea ice-rafted sediments are important factors for the albedo and for the ecology and productivity of marine organisms, because of the absorption of solar radiation and lowered light transmission. Beginning in 1987 in the Eastern Arctic Basin and continuing in 1988, 1989 and 1990 in Fram Strait, Barents Sea and Greenland Sea the authors conducted a multi-disciplinary sea ice project on the role and importance of sea ice-rafted sediments for sedimentation in the Arctic Ocean. During the field work very high sediment accumulations were observed and sampled (up to 560 g sediment/kg ice). Most of the material was concentrated in small patches of 1-10 m in diameter, but in some areas, especially in the Eastern Arctic, they covered up to 80% of the ice surface and formed layers of pure mud, 2-3 cm thick. First estimations of the observed concentrations, the annual ice flow through Fram Strait, and the average sedimentation rate in this area show that the necessary sediment flux can be obtained only by sea ice. Thus, sea ice-rafting seems to be the most important input mechanism of fine grained terrigenous (biogenic and terrigenic) sediment into the ice-covered deep sea regions

  3. Arctic aerosol life cycle: linking aerosol size distributions observed between 2000 and 2010 with air mass transport and precipitation at Zeppelin station, Ny-Ålesund, Svalbard

    Directory of Open Access Journals (Sweden)

    P. Tunved

    2012-11-01

    Full Text Available In this study we present a qualitative and quantitative assessment of more the 10 yr of aerosol number size distribution data observed in the Arctic environment (Mt Zeppelin (78°56' N, 11°53' E, 474 m a.s.l., Ny Ålesund, Svalbard. We provide statistics on both seasonal and diurnal characteristics of the aerosol observations and conclude that the Arctic aerosol number size distribution and auxiliary parameters such as integral mass and surface have a very pronounced seasonal variation. This seasonal variation seems to be controlled by both dominating source as well as meteorological conditions in general. In principle, three distinctly different periods can be identified during the Arctic year: the haze period characterized by a dominating accumulation mode aerosol (March–May followed by the sunlit summer period with low abundance of accumulation mode particles but high concentration of small particles which likely are recently and locally formed (June–August. The rest of the year is characterized by comparably low concentration of accumulation mode particles and negligible abundance of ultra fine particles (September–February. Minimum aerosol mass and number concentration is usually observed during September/October. We further show that the transition between the different regimes is fast, suggesting rapid change in conditions defining their appearance. A source climatology based on trajectory analysis is provided and it is shown that there is a strong seasonality of dominating source areas, with dominance of Eurasia during the autumn-winter period and dominance of North Atlantic air during the summer months. We also show that new particle formation events seem to be a rather common phenomenon during the Arctic summer, and this is the result of both photochemical production of nucleating/condensing species and low condensation sink. It is also suggested that wet removal play a key role in defining the Arctic aerosol year, and plays a

  4. Organohalogenated Contaminants in Eggs of Snow Buntings (Plectrophenax nivalis) from Human Settlements in Svalbard

    OpenAIRE

    Kristoffersen, Siv

    2012-01-01

    Contaminants in the Arctic environment are mainly transported from lower latitude areas by atmospheric transport. However, the Russian settlements (Barentsburg and Pyramiden) in Svalbard have shown to be heavily influenced by local pollution of polychlorinated biphenyls (PCB), as high concentrations have been found in vegetation, soil and sediments. The Norwegian settlements (Longyearbyen and Ny-Ålesund) are to a lesser extent influenced by local pollution of PCB. Birds have been utilize...

  5. Eolian sediments in arctic Alaska as sources of paleoenvironmental data

    International Nuclear Information System (INIS)

    Eolian sand, silt, and associated fluvial and lacustrine sediments are widespread in Alaska north of the Brooks Range. These sediments and intercalated paleosols record late Quaternary episodes of widespread eolian sediment transport separated by periods of relative landscape stability and the growth of organic soils. The eolian sediments represent paleoenvironments much different from the modem one, in which eolian sediment transport is principally limited to areas adjacent to sediment sources, such as flood plains. Information about these paleoenvironments and their contemporary climates can be obtained by studying the morphology, distribution, and sedimentology of the sediments, and the fossil fauna and flora they contain. Fossils such as beetles and ostracods contained in the fluvial and lacustrine sediments can yield information regarding summer temperature and changes in evaporation/precipitation ratios. Furthermore, the sediments and paleosols can be dated by thermoluminescence and radiocarbon to provide a chronology of paleoclimatic and pale-environmental change. Present data suggest three major episodes of widespread eolian sediment movement during the latest glacial/inter-glacial cycle: (1) a long period coincident with the Wisconsin glaciation during which climate was cooler and drier than today and much of the North Slope was a polar desert; (2) an interval during the latest Pleistocene and early Holocene in which climate was warmer and surface moisture conditions were drier than today; and; (3) one or more brief late Holocene intervals during which climate was probably cooler and drier than today. These eolian sediments and intercalated paleosols are being studied in detail as part of the USGS Climate Change Program in order to understand how past environments in arctic Alaska have responded to climatic change

  6. Diversity and novelty of actinobacteria in Arctic marine sediments.

    Science.gov (United States)

    Zhang, Gaiyun; Cao, Tingfeng; Ying, Jianxi; Yang, Yanliu; Ma, Lingqi

    2014-04-01

    The actinobacterial diversity of Arctic marine sediments was investigated using culture-dependent and culture-independent approaches. A total of 152 strains were isolated from seven different media; 18 isolates were selected for phylogenetic analysis on the basis of their 16S rRNA gene sequences. Results showed that the 18 isolates belonged to a potential novel genus and 10 known genera including Actinotalea, Arthrobacter, Brachybacterium, Brevibacterium, Kocuria, Kytococcus, Microbacterium, Micrococcus, Mycobacterium, and Pseudonocardia. Subsequently, 172 rDNA clones were selected by restriction fragment length polymorphism analysis from 692 positive clones within four actinobacteria-specific 16S rDNA libraries of Arctic marine sediments, and then these 172 clones were sequenced. In total, 67 phylotypes were clustered in 11 known genera of actinobacteria including Agrococcus, Cellulomonas, Demequina, Iamia, Ilumatobacter, Janibacter, Kocuria, Microbacterium, Phycicoccus, Propionibacterium, and Pseudonocardia, along with other, unidentified actinobacterial clones. Based on the detection of a substantial number of uncultured phylotypes showing low BLAST identities (<95 %), this study confirms that Arctic marine environments harbour highly diverse actinobacterial communities, many of which appear to be novel, uncultured species. PMID:24519808

  7. Longyearbyen, Svalbard, Norway

    Science.gov (United States)

    2008-01-01

    Longyearbyen is the administrative center of Svalbard and is located on Spitsbergen, the largest island of the Svalbard archipelago, part of the Kingdom of Norway. It is the world's northernmost town with over 1000 people. The settlement was founded in 1906 by John Longyear, owner of the Arctic Coal Company. Until the early 1990s the coal mining industry was the major employer of Longyearbyen. Near Longyearbyen, the Global Crop Diversity Trust administers the Svalbard Global Seed Vault, an Arctic safe capable of storing millions of crop seeds as a safeguard against natural and human disasters. Last week, the first deposit of 250,000 different species of crop seeds was made into the repository. The perspective view was created by draping a simulated natural color image over an ASTER-derived digital elevation model. The image was acquired July 12, 2003, and is located at 78.2 degrees north latitude, 15.6 degrees east longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  8. Three-year vegetation change in the Arctic environment as observed in a permanent plot in Ny-Alesund, Svalbard

    OpenAIRE

    Satoru, Kojima

    2004-01-01

    A permanent plot was established in 1997 to monitor vegetation development in a recently abandoned coal mine in Ny-_lesund, Svalbard. A 1 mx1 m quadrat was set up and further divided into one hundred small 10 cmx10 cm cells. All the vascular plants occurring in the plot were recorded for each of the 100 cells. In 1999, the plot was revisited and examined for occurrences of vascular plants. Further, in 2002, the plot was re-surveyed and all the vascular plants were measured for their coverage....

  9. Heterotopisk Svalbard-krim

    Directory of Open Access Journals (Sweden)

    Lisbeth Pettersen Wærp

    2015-04-01

    Full Text Available How is the Arctic represented in modern crime fiction written by a female glaciologist, meterologist and polar explorer? Monica Kristensen is the author of a new, critically acclaimed, series of crime novels set in Svalbard. The first four novels of the series are Hollendergraven (2007, The Dutchman's Grave, Kullunge (2008, Coal Baby, Operasjon Fritham (2009, Operation Fritham, Den døde i Barentsburg (2011, The Dead Man in Barentsburg and Ekspedisjonen (2014, The Expedition. According to the publisher, Forlaget Press, the series, when completed, will consist of altogether 12 books. The originality of the series is the use of Svalbard as setting. The setting is not only spectacular, it is significant: Knowledge of nature and climate is of greatest importance to the characters, the protagonist, police officer (sysselmannsbetjent Knut Fjeld, as well as his various antagonists. Svalbard is not only a place in the Arctic, but also a group of islands. Both aspects are effectively exploited in Kristensen's novels. The representation of the Arctic archipelago is to a great extent based on the differences from other places, e.g. mainland Norway. The arcticle argues that the arctic archipelago as represented in these novels comes close to what French philosopher Michel Foucault calls heterotopia: A place that is totally different from other places, a place that represents the other, the deviant, and like the utopia and dystopia reflects the world of which it is an extension. Heterotopia is Foucault’s neologism (1967, and unlike the utopia/dystopia, the heterotopia actually exists. Within this theoretical framework the article presents a reading of the first five novels with special emphasis on the exploitation of place.

  10. HEAVY METAL ACCUMULATION IN SEDIMENT AND FRESHWATER FISH IN U.S. ARCTIC LAKES

    Science.gov (United States)

    Metal concentrations in sediment and two species of freshwater fish (lake trout [Salvelinus namaycush], and grayling [Thymallus arcticus]} were examined in four Arctic lakes in Alaska. Concentrations of several metals were naturally high in the sediment relative to uncontaminated...

  11. Quantification of sediment budgets at an arctic delta

    Science.gov (United States)

    Kroon, A.; Bendixen, M.; Sigsgaard, C.

    2012-12-01

    The impact of ice and snow and freezing temperatures make arctic polar coastal environments quite unique and different from other coastal environments for instance in temperate zones or in tropic areas. The coastal processes and the morphologic evolution of landforms in these areas are strongly influenced by common factors such as cold temperatures, (dis)continuous or sporadic permafrost, and the presence of sea ice cover. Most of these factors have a strong seasonality and the impact of classic coastal processes by waves and tides are often limited to the summer and early fall. Global climate changes induce a lot of changes along the arctic coasts. Sea-levels are rising due to an increased fresh water flux from the glaciers and land ice masses. At the same time, the ice coverage of the coastal waters decreases and the open water periods in summer extend. This might cause extra wave activity with higher erosion rates along many of the shorelines. Many fjords and open coastal stretches in North-East Greenland have deltas. The sources for the sediments for these deltas are located in the drainage basins of rivers that are fed by melting glaciers. These rivers drain pro-glacial and fluvial valleys and may also deliver additional sediment by eroding glacial and peri-glacial deposits in the present coastal plain. Minor sources of sediment transport towards the delta come from reworking of sediments on the delta slope, through lateral transport from the adjacent shores, and through stranded sediment-loaded ice out of the fjord. Losses of sediments occur through further fluvial sediment transport over the delta towards the fjord, or by reworking of delta fringes by coastal processes due to ice, waves and tides. Sandy spits and small barriers often fringe the shoreline of a delta. These features are typically formed and active in the ice-free periods when coastal processes by waves and drifting ice rework the delta front and adjacent coastal cliffs. In this presentation

  12. Winter Sea Ice Deformation Measured by Autonomous Buoys During the N-ICE2015 Cruise in the Arctic Ocean North of Svalbard

    Science.gov (United States)

    Itkin, P.; Spreen, G.; Gerland, S.

    2015-12-01

    The motion of the sea ice cover in the Arctic Ocean north of Svalbard is characterized by fast sea ice drift (10 to 70 km/day) during the winter season. The Norwegian Young sea ICE cruise (N-ICE2015) took place in that region from January till June 2015. During this period more than 40 buoys in nested arrays at the distance of 5 to 100 km apart from each other were deployed in 2 deployments (in January/February and in April/May). The buoy types include drifters, snow buoys, ice-mass balance buoys, radiation buoys and wave buoys. The buoys were deployed on the first- and second-year ice that was characteristic for the region. The sea ice dynamics measured by these buoy arrays are explored in relation to the changing atmospheric forcing and internal ice stress during the experiment. The deformation rates obtained from the buoy array are on average higher than measured by buoy experiments in other Arctic regions by earlier experiments. Our preliminary results show a strong connection of the deformation events to the atmospheric forcing. The high sea ice drift speed associated to strong winds is connected to high deformation rates, while the low speeds in the calm periods are connected to the low deformation rates. While it is known that the relationship between the deformation rate and the spatial scale over which it is measured can be represented by a power law (Stern and Lindsay, 2009, JGR), we find that the exponent is not constant over time and space during the experiment. For high ice drift speeds, associated with high wind speeds and a more loose ice cover, the exponent becomes more negative than for lower ice drift speeds and a compressed ice cover. Figure: Locations of buoy deployments and buoy types for all the buoys deployed during the N-ICE2015 cruise.

  13. The bird ectoparasite Dermanyssus hirundinis (Acari, Mesostigmata) in the High Arctic; a new parasitic mite to Spitsbergen, Svalbard.

    Science.gov (United States)

    Gwiazdowicz, Dariusz J; Coulson, Stephen J; Grytnes, John-Arvid; Pilskog, Hanne Eik

    2012-12-01

    Ectoparasites are common on birds and in their nests. Amongst these parasites are diverse gamasid mite species that can lead to irritation, disease transmission and blood loss. Few studies of the ectoparasites of birds breeding in the High Arctic exist. The parasitic mite, Dermanyssus hirundinis, was found in nests of snow buntings Plectrophenax nivalis nivalis, both natural nests and within nesting boxes, on Spitsbergen. Densities per nest varied from sporadic to greater than 26,000 individuals. This is the northernmost observation of this parasite. The mite was present in new nests, nests constructed the previous year and nests not utilized the previous summer. The parasite survives at least 18 months without access to a blood meal and can tolerate the Arctic winter, surviving temperatures below -20°C. D. hirundinis is hence well adapted to arctic conditions. Only females were observed suggesting that this population is facultatively parthenogenetic. PMID:23129197

  14. Trace elements and cathodoluminescence of detrital quartz in Arctic marine sediments – a new ice-rafted debris provenance proxy

    Directory of Open Access Journals (Sweden)

    A. Müller

    2013-07-01

    Full Text Available The records of ice-rafted debris (IRD provenance in the North Atlantic – Barents Sea allow the reconstruction of the spatial and temporal changes of ice-flow drainage patterns during glacial and deglacial periods. In this study a new approach to characterisation of the provenance of detrital quartz grains in the fraction > 500 μm of marine sediments offshore of Spitsbergen is introduced, utilizing scanning electron microscope backscattered electron and cathodoluminescence (CL imaging, combined with laser ablation inductively-coupled plasma mass spectrometry. Based on their micro-inclusions, CL and trace element characteristics the investigated IRD grains can be classified into five distinct populations. Three of the populations are indicative of potential IRD provenance provinces in the Storfjord area including Barentsøya and Egdeøya. The results imply that under modern (interglacial conditions IRD deposition along the western Spitsbergen margin is mainly governed by the East Svalbard Current controlling the ice-drift pattern. The presence of detrital quartz from local provinces, however, indicates that variations in IRD supply from western Spitsbergen may be quantified as well. In this pilot study it is demonstrated that this new approach applied on Arctic continental margin sediments, bears a considerable potential for the definition of the sources of IRD and thus of spatial/temporal changes in ice-flow drainage patterns during glacial/interglacial cycles.

  15. In-situ calibration and validation of Cryosat-2 observations over arctic sea ice north of Svalbard

    DEFF Research Database (Denmark)

    Gerland, Sebastian; Renner, Angelika H. H.; Spreen, Gunnar;

    CryoSat-2's radar altimeter allows to observe the panArctic sea ice thickness up to 88°N on a monthly basis. However, calibration and validation are crucial to assess limitations and accuracy of the altimeter, and to better quantify the uncertainties involved in converting sea ice freeboard to...

  16. Desulfotomaculum arcticum sp nov., a novel spore-formin, moderately thermophilic, sulfate-reducing bacterium isolated from a permanently cold fjord sediment of Svalbard

    DEFF Research Database (Denmark)

    Vandieken, V.; Knoblauch, C.; Jørgensen, BB

    2006-01-01

    Strain 15 T is a novel spore-forming, sulfate-reducing bacterium isolated from a permanently cold fjord sediment of Svalbard. Sulfate could be replaced by sulfite or thiosulfate. Hydrogen, formate, lactate, propionate, butyrate, hexanoate, methanol, ethanol, propanol, butanol, pyruvate, malate...... closely related to Desulfotomaculum thermosapovorans MLF(T) (93-5% 16S rRNA gene sequence similarity). Strain 15 T represents a novel species, for which the name Desulfotomaculurn arcticum sp. nov. is proposed. The type strain is strain 15 T (=DSM 17038(T)=jCM 12923(T))....

  17. Deepened winter snow increases stem growth and alters stem δ13C and δ15N in evergreen dwarf shrub Cassiope tetragona in high-arctic Svalbard tundra

    International Nuclear Information System (INIS)

    Deeper winter snow is hypothesized to favor shrub growth and may partly explain the shrub expansion observed in many parts of the arctic during the last decades, potentially triggering biophysical feedbacks including regional warming and permafrost thawing. We experimentally tested the effects of winter snow depth on shrub growth and ecophysiology by measuring stem length and stem hydrogen (δ2H), carbon (δ13C), nitrogen (δ15N) and oxygen (δ18O) isotopic composition of the circumarctic evergreen dwarf shrub Cassiope tetragona growing in high-arctic Svalbard, Norway. Measurements were carried out on C. tetragona individuals sampled from three tundra sites, each representing a distinct moisture regime (dry heath, meadow, moist meadow). Individuals were sampled along gradients of experimentally manipulated winter snow depths in a six-year old snow fence experiment: in ambient (c. 20 cm), medium (c. 100 cm), and deep snow (c. 150 cm) plots. The deep-snow treatment consistently and significantly increased C. tetragona growth during the 2008–2011 manipulation period compared to growth in ambient-snow plots. Stem δ15N and stem N concentration values were significantly higher in deep-snow individuals compared to individuals growing in ambient-snow plots during the course of the experiment, suggesting that soil N-availability was increased in deep-snow plots as a result of increased soil winter N mineralization. Although inter-annual growing season-precipitation δ2H and stem δ2H records closely matched, snow depth did not change stem δ2H or δ18O, suggesting that water source usage by C. tetragona was unaltered. Instead, the deep insulating snowpack may have protected C. tetragona shrubs against frost damage, potentially compensating the detrimental effects of a shortened growing season and associated phenological delay on growth. Our findings suggest that an increase in winter precipitation in the High Arctic, as predicted by climate models, has the potential to

  18. Current status, between-year comparisons and maternal transfer of organohalogenated compounds (OHCs) in Arctic char (Salvelinus alpinus) from Bjørnøya, Svalbard (Norway)

    Energy Technology Data Exchange (ETDEWEB)

    Bytingsvik, J., E-mail: jenny.bytingsvik@akvaplan.niva.no [Akvaplan-niva AS, The Fram Centre, N-9296 Tromsø Norway (Norway); Frantzen, M. [Akvaplan-niva AS, The Fram Centre, N-9296 Tromsø Norway (Norway); Götsch, A.; Heimstad, E.S. [NILU (Norwegian Institute for Air Research), The Fram Centre, N-9296 Tromsø Norway (Norway); Christensen, G. [Akvaplan-niva AS, The Fram Centre, N-9296 Tromsø Norway (Norway); Evenset, A. [Akvaplan-niva AS, The Fram Centre, N-9296 Tromsø Norway (Norway); University of Tromsø, The Arctic University of Norway, Pb 6050 Langnes, N-9037 Tromsø (Norway)

    2015-07-15

    High levels of organohalogenated compounds (OHCs) have been found in Arctic char from Lake Ellasjøen at Bjørnøya (Svalbard, Norway) compared to char from other arctic lakes. The first aim of the study was to investigate the OHC status, contaminant profile, and partitioning of OHCs between muscle and ovary tissue in spawning female char from the high-polluted Lake Ellasjøen and the low-polluted Lake Laksvatn. The second aim was to investigate if OHC levels in muscle tissue have changed over time. Between-lake comparisons show that the muscle levels (lipid weight) of hexachlorobenzene (HCB), chlordanes (∑ CHLs), mirex, dichlorodiphenyltrichloroethanes (∑ DDTs) and polychlorinated biphenyls (∑ PCBs) were up to 36 times higher in char from Ellasjøen than in Laksvatn, and confirm that the char from Ellasjøen are still heavily exposed compared to char from neighboring lake. A higher proportion of persistent OHCs were found in Ellasjøen compared to Laksvatn, while the proportion of the less persistent OHCs was highest in Laksvatn. A between-year comparison of OHC levels (i.e., HCB, DDTs, PCBs) in female and male char shows higher levels of HCB in female char from Ellasjøen in 2009/2012 compared to in 1999/2001. No other between-year differences in OHC levels were found. Due to small study groups, findings associated with between-year differences in OHC levels should be interpreted with caution. OHCs accumulate in the lipid rich ovaries of spawning females, resulting in up to six times higher levels of OHCs in ovaries compared to in muscle (wet weight). The toxic equivalent (TEQ)-value for the dioxin-like PCBs (PCB-105 and -118) in ovaries of the Ellasjøen char exceeded levels associated with increased egg mortality in rainbow trout (Oncorhynchus mykiss). Hence, we suggest that future studies should focus on the reproductive health and performance abilities of the high-exposed population of char inhabiting Lake Ellasjøen. - Highlights: • Examine levels

  19. Diagenetic regimes in Arctic Ocean sediments: Implications for sediment geochemistry and core correlation

    Science.gov (United States)

    Meinhardt, A.-K.; März, C.; Schuth, S.; Lettmann, K. A.; Schnetger, B.; Wolff, J.-O.; Brumsack, H.-J.

    2016-09-01

    Dark brown sediment layers are a potential stratigraphic tool in Quaternary Arctic Ocean sediments. They are rich in Mn, Fe, and trace metals scavenged from the water column and were most likely deposited during interglacial intervals. In this study, we combine sediment and pore water data from sediment cores taken in different parts of the Arctic Ocean to investigate the influence of early diagenetic processes on sediment geochemistry. In most studied cores, Mn, Co, and Mo are released into the pore waters from Mn oxide dissolution in deeper (>1.5 m) sediment layers. The relationship between sedimentary Mn, Co, and Mo contents in excess of the lithogenic background (elementxs) shows that Coxs/Moxs values are a diagnostic tool to distinguish between layers with diagenetic metal addition from the pore waters (Coxs/Moxs 10), and unaffected layers (Coxs/Moxs from 1 to 10). Steady-state calculations based on current pore water profiles reveal that in the studied cores, the diagenetic addition of these metals from the pore water pool alone is not sufficient to produce the sedimentary metal enrichments. However, it seems evident that dissolution of Mn oxides in the Mn reduction zone can permanently alter the primary geochemical signature of the dark brown layers. Therefore, pore water data and Coxs/Moxs values should be considered before core correlation when this correlation is solely based on Mn contents and dark sediment color. In contrast to the mostly non-lithogenic origin of Mn in the dark brown layers, sedimentary Fe consists of a large lithogenic (80%) and a small non-lithogenic fraction (20%). Our pore water data show that diagenetic Fe remobilization is not currently occurring in the sediment. The dominant Fe sources are coastal erosion and river input. Budget calculations show that Fe seems to be trapped in the modern Arctic Ocean and accumulates in shelf and basin sediments. The Fe isotopic signal δ56Fe of the solid phase is positive (∼0.2-0.3‰) in

  20. In situ response of Nostoc commune s.l. colonies to desiccation in Central Svalbard, Norwegian High Arctic

    Czech Academy of Sciences Publication Activity Database

    Kvíderová, Jana; Elster, Josef; Šimek, Miloslav

    2011-01-01

    Roč. 11, č. 1 (2011), s. 87-97. ISSN 1802-5439 R&D Projects: GA MŠk ME 934; GA MŠk LA341; GA MŠk LC06066; GA AV ČR IAA600660605 Institutional research plan: CEZ:AV0Z60050516; CEZ:AV0Z60660521 Keywords : desiccation * cyanobacteria * Arctic Subject RIV: EF - Botanics Impact factor: 1.327, year: 2011

  1. Organohalogenated Contaminants in Eggs of Snow Buntings (Plectrophenax nivalis) from Human Settlements in Svalbard

    OpenAIRE

    Kristoffersen, Siv

    2012-01-01

    Contaminants in the Arctic environment are mainly transported from lower latitude areas by atmospheric transport. However, the Russian settlements (Barentsburg and Pyramiden) in Svalbard have shown to be heavily influenced by local pollution of polychlorinated biphenyls (PCB), as high concentrations have been found in vegetation, soil and sediments. The Norwegian settlements (Longyearbyen and Ny-Ålesund) are to a lesser extent influenced by local pollution of PCB. Birds have been utilize...

  2. Response of Methanogens in Arctic Sediments to Temperature and Methanogenic Substrate Availability.

    Science.gov (United States)

    Blake, Lynsay I; Tveit, Alexander; Øvreås, Lise; Head, Ian M; Gray, Neil D

    2015-01-01

    Although cold environments are major contributors to global biogeochemical cycles, comparatively little is known about their microbial community function, structure, and limits of activity. In this study a microcosm based approach was used to investigate the effects of temperature, and methanogenic substrate amendment, (acetate, methanol and H2/CO2) on methanogen activity and methanogen community structure in high Arctic wetlands (Solvatnet and Stuphallet, Svalbard). Methane production was not detected in Stuphallet sediment microcosms (over a 150 day period) and occurred within Solvatnet sediments microcosms (within 24 hours) at temperatures from 5 to 40°C, the maximum temperature being at far higher than in situ maximum temperatures (which range from air temperatures of -1.4 to 14.1°C during summer months). Distinct responses were observed in the Solvatnet methanogen community under different short term incubation conditions. Specifically, different communities were selected at higher and lower temperatures. At lower temperatures (5°C) addition of exogenous substrates (acetate, methanol or H2/CO2) had no stimulatory effect on the rate of methanogenesis or on methanogen community structure. The community in these incubations was dominated by members of the Methanoregulaceae/WCHA2-08 family-level group, which were most similar to the psychrotolerant hydrogenotrophic methanogen Methanosphaerula palustris strain E1-9c. In contrast, at higher temperatures, substrate amendment enhanced methane production in H2/CO2 amended microcosms, and played a clear role in structuring methanogen communities. Specifically, at 30°C members of the Methanoregulaceae/WCHA2-08 predominated following incubation with H2/CO2, and Methanosarcinaceaeand Methanosaetaceae were enriched in response to acetate addition. These results may indicate that in transiently cold environments, methanogen communities can rapidly respond to moderate short term increases in temperature, but not

  3. Response of Methanogens in Arctic Sediments to Temperature and Methanogenic Substrate Availability.

    Directory of Open Access Journals (Sweden)

    Lynsay I Blake

    Full Text Available Although cold environments are major contributors to global biogeochemical cycles, comparatively little is known about their microbial community function, structure, and limits of activity. In this study a microcosm based approach was used to investigate the effects of temperature, and methanogenic substrate amendment, (acetate, methanol and H2/CO2 on methanogen activity and methanogen community structure in high Arctic wetlands (Solvatnet and Stuphallet, Svalbard. Methane production was not detected in Stuphallet sediment microcosms (over a 150 day period and occurred within Solvatnet sediments microcosms (within 24 hours at temperatures from 5 to 40°C, the maximum temperature being at far higher than in situ maximum temperatures (which range from air temperatures of -1.4 to 14.1°C during summer months. Distinct responses were observed in the Solvatnet methanogen community under different short term incubation conditions. Specifically, different communities were selected at higher and lower temperatures. At lower temperatures (5°C addition of exogenous substrates (acetate, methanol or H2/CO2 had no stimulatory effect on the rate of methanogenesis or on methanogen community structure. The community in these incubations was dominated by members of the Methanoregulaceae/WCHA2-08 family-level group, which were most similar to the psychrotolerant hydrogenotrophic methanogen Methanosphaerula palustris strain E1-9c. In contrast, at higher temperatures, substrate amendment enhanced methane production in H2/CO2 amended microcosms, and played a clear role in structuring methanogen communities. Specifically, at 30°C members of the Methanoregulaceae/WCHA2-08 predominated following incubation with H2/CO2, and Methanosarcinaceaeand Methanosaetaceae were enriched in response to acetate addition. These results may indicate that in transiently cold environments, methanogen communities can rapidly respond to moderate short term increases in temperature, but

  4. Arctic soil development on a series of marine terraces on central Spitsbergen, Svalbard: a combined geochronology, fieldwork and modelling approach

    Science.gov (United States)

    van der Meij, W. Marijn; Temme, Arnaud J. A. M.; de Kleijn, Christian M. F. J. J.; Reimann, Tony; Heuvelink, Gerard B. M.; Zwoliński, Zbigniew; Rachlewicz, Grzegorz; Rymer, Krzysztof; Sommer, Michael

    2016-06-01

    Soils in Arctic regions currently enjoy attention because of their sensitivity to climate change. It is therefore important to understand the natural processes and rates of development of these soils. Specifically, there is a need to quantify the rates and interactions between various landscape- and soil-forming processes. Soil chronosequences are ideal natural experiments for this purpose. In this contribution, we combine field observations, luminescence dating and soil-landscape modelling to improve and test our understanding of Arctic soil formation. The field site is a Holocene chronosequence of gravelly raised marine terraces in central Spitsbergen. Field observations show that soil-landscape development is mainly driven by weathering, silt translocation, aeolian deposition and rill erosion. Spatial soil variation is mainly caused by soil age, morphological position within a terrace and depth under the surface. Luminescence dating confirmed existing radiocarbon dating of the terraces, which are between ˜ 1.5 and ˜ 13.3 ka old. The soil-landscape evolution model LORICA was used to test our hypothesis that the field-observed processes indeed dominate soil-landscape development. Model results additionally indicated the importance of aeolian deposition as a source of fine material in the subsoil for both sheltered and vegetated trough positions and barren ridge positions. Simulated overland erosion was negligible. Consequently, an un-simulated process must be responsible for creating the observed erosion rills. Dissolution and physical weathering both play a major role. However, using present-day soil observations, the relative contribution of physical and chemical weathering could not be disentangled. Discrepancies between field and model results indicate that soil formation is non-linear and driven by spatially and temporally varying boundary conditions which were not included in the model. To conclude, Arctic soil and landscape development appears to be more

  5. Field Characterization of the Mineralogy and Organic Chemistry of Carbonates from the 2010 Arctic Mars Analog Svalbard Expedition by Evolved Gas Analysis

    Science.gov (United States)

    McAdam, A. C.; Ten Kate, I. L.; Stern, J. C.; Mahaffy, P. R.; Blake, D. F.; Morris, R. V.; Steele, A.; Amundson, H. E. F.

    2011-01-01

    The 2010 Arctic Mars Analog Svalbard Expedition (AMASE) investigated two geologic settings using methodologies and techniques being developed or considered for future Mars missions, such as the Mars Science Laboratory (MSL), ExoMars, and Mars Sample Return. The Sample Analysis at Mars (SAM) [1] instrument suite, which will be on MSL, consists of a quadrupole mass spectrometer (QMS), a gas chromatograph (GC), and a tunable laser mass spectrometer (TLS); all will be applied to analyze gases created by pyrolysis of samples. During AMASE, a Hiden Evolved Gas Analysis-Mass Spectrometer (EGA-MS) system represented the EGA-MS capability of SAM. Another MSL instrument, CheMin, will use x-ray diffraction (XRD) and x-ray fluorescence (XRF) to perform quantitative mineralogical characterization of samples [e.g., 2]. Field-portable versions of CheMin were used during AMASE. AMASE 2010 focused on two sites that represented biotic and abiotic analogs. The abiotic site was the basaltic Sigurdfjell vent complex, which contains Mars-analog carbonate cements including carbonate globules which are excellent analogs for the globules in the ALH84001 martian meteorite [e.g., 3, 4]. The biotic site was the Knorringfjell fossil methane seep, which featured carbonates precipitated in a methane-supported chemosynthetic community [5]. This contribution focuses on EGA-MS analyses of samples from each site, with mineralogy comparisons to CheMin team results. The results give insight into organic content and organic-mineral associations, as well as some constraints on the minerals present.

  6. Chemical composition of sediments from White Sea, Russian Arctic

    Science.gov (United States)

    Gamza, Olga; Shevchenko, Vladimir; Novigatsky, Aleksandr

    2010-05-01

    The White Sea, the only Russian inland sea, is located on the north of outlying districts of the European part of Russia, belongs to Arctic Ocean. Area of water of sea occupies about 90 tousend square kilometers. The sea can be divided into some general parts: neck, funnel, basin and 4 Bays: Dvina Bay, Kandalaksha Bay, Mezen Bay and Onega Bay. The purpose of this work was geochemical mapping of the surface sediments of this area. The main tasks were: compilation data base of element composition of the surface sediments, geochemical mapping of each element, research of the anormal concentration of elements on the surface. To detect the content of chemical elements several methods were used: atomic absorption spectrometry (P.P. Shirshov Institute of Oceanology); neutron activation analysis (Vernadsky Institute of Geochemistry and Analytical Chemistry), total and organic carbon analysis, photometric method to detection Si, Al, P (P.P. Shirshov Institute of Oceanology). Bulk composition is one of the fundamental characteristics of sediments and bottom deposites of modern basins. Coarse-grained sediments with portion of pelitic component 80%). Character of elements distribution correlates with facial distribution of sediments from White Sea. According to litologic description, bottom surface of Dvina Bay is practically everywhere covered by layer of fine-grained sand. In the border area between Dvina Bay and White Sea basin on terraced subwater slope aleurite politic silts are abundant. They tend to exhange down the slope to clay silts. In Onega Bay fractions of non-deposition are observed. They are characterized by wide spread of thin blanket poorgraded sediments, which are likely to be relic. Relief of Kandalakscha Bay bottom is presented as alternation of abyssal fosses (near 300 m) with silles and elevations (depressions and in central part of the sea, which is quite wide from both places of original sedimentation and run off sources [2]. Thus, the interrelation

  7. Tectonic Map of the Ellesmerian and Eurekan deformation belts on Svalbard, North Greenland and the Queen Elizabeth Islands (Canadian Arctic)

    Science.gov (United States)

    Piepjohn, Karsten; von Gosen, Werner; Tessensohn, Franz; Reinhardt, Lutz; McClelland, William C.; Dallmann, Winfried; Gaedicke, Christoph; Harrison, Christopher

    2016-04-01

    The tectonic map presented here shows the distribution of the major post-Ellesmerian and pre-Eurekan sedimentary basins, parts of the Caledonian Orogen, the Ellesmerian Fold-and-Thrust Belt, structures of the Cenozoic Eurekan deformation, and areas affected by the Eurekan overprint. The present continental margin of North America towards the Arctic Ocean between the Queen Elizabeth Islands and Northeast Greenland and the present west margin of the Barents Shelf are characterized by the Paleozoic Ellesmerian Fold-and-Thrust Belt, the Cenozoic Eurekan deformation, and, in parts, the Caledonian Orogen. In many areas, the structural trends of the Ellesmerian and Eurekan deformations are more or less parallel, and often, structures of the Ellesmerian Orogeny are affected or reactivated by the Eurekan deformation. While the Ellesmerian Fold-and-Thrust Belt is dominated by orthogonal compression and the formation of wide fold-and-thrust zones on Ellesmere Island, North Greenland and Spitsbergen, the Eurekan deformation is characterized by a complex network of regional fold-and-thrust belts (Spitsbergen, central Ellesmere Island), large distinct thrust zones (Ellesmere Island, North Greenland) and a great number of strike-slip faults (Spitsbergen, Ellesmere Island). The Ellesmerian Fold-and-Thrust Belt was most probably related to the approach and docking of the Pearya Terrane (northernmost part of Ellesmere Island) and Spitsbergen against the north margin of Laurasia (Ellesmere Island/North Greenland) in the earliest Carboniferous. The Eurekan deformation was related to plate tectonic movements during the final break-up of Laurasia and the opening of Labrador Sea/Baffin Bay west, the Eurasian Basin north, and the Norwegian/Greenland seas east of Greenland. The tectonic map presented here shows the German contribution to the Tectonic Map of the Arctic 1:5,000,000 (TeMAr) as part of the international project "Atlas of geological maps of Circumpolar Arctic at 1

  8. Arctic soil development on a series of marine terraces on Central Spitsbergen, Svalbard: a combined geochronology, fieldwork and modelling approach

    Science.gov (United States)

    van der Meij, W. M.; Temme, A. J. A. M.; de Kleijn, C. M. F. J. J.; Reimann, T.; Heuvelink, G. B. M.; Zwoliński, Z.; Rachlewicz, G.; Rymer, K.; Sommer, M.

    2015-12-01

    Soils in Arctic regions currently enjoy significant attention because of their potentially substantial changes under climate change. It is important to quantify the natural processes and rates of development of these soils, to better define and determine current and future changes. Specifically, there is a need to quantify the interactions between various landscape and soil forming processes that together have resulted in current soil properties. Soil chronosequences are ideal natural experiments for this purpose. In this contribution, we combine field observations, luminescence dating and soil-landscape modelling to test and improve our understanding about Arctic soil formation. Our field site is a Holocene chronosequence of gravelly raised marine terraces in central Spitsbergen. Field observations suggest that soil-landscape development is mainly driven by weathering, silt translocation, aeolian deposition and rill erosion. Spatial soil heterogeneity is mainly caused by soil age, morphological position and depth under the surface. Substantial organic matter accumulation only occurs in few, badly drained positions. Luminescence dating confirmed existing radiocarbon dating of the terraces, which are between ~ 3.6 and ~ 14.4 ka old. Observations and ages were used to parameterize soil landscape evolution model LORICA, which was subsequently used to test the hypothesis that our field-observed processes indeed dominate soil-landscape development. Model results indicate the importance of aeolian deposition as a source of fine material in the subsoil for both sheltered beach trough positions and barren beach ridge positions. Simulated overland erosion was negligible. Therefore, an un-simulated process must be responsible for creating the observed erosion rills. Dissolution and physical weathering both play a major role. However, by using present day soil observations, relative physical and chemical weathering could not be disentangled. Discrepancies between field and

  9. Alien plant species in Svalbard

    OpenAIRE

    Roalsø, Erik Roall

    2012-01-01

    Increased introductions combined with favorable growing conditions may enhance the presence and increase the success of alien plant species in High Arctic settlements. With global warming, the presence and success of alien plants in Polar Regions might expand beyond the confinement of human settlements and cause problems for native species and ecosystems. Presence and abundance of alien and native vascular plant species were recorded, from chosen study sites, in the Svalbard settlements of Ba...

  10. Deepened winter snow increases stem growth and alters stem δ13C and δ15N in evergreen dwarf shrub Cassiope tetragona in high-arctic Svalbard tundra

    DEFF Research Database (Denmark)

    Blok, Daan; Weijers, Stef; Welker, Jeffrey M;

    2015-01-01

    ), medium ( c . 100 cm), and deep snow ( c . 150 cm) plots. The deep-snow treatment consistently and significantly increased C. tetragona growth during the 2008–2011 manipulation period compared to growth in ambient-snow plots. Stem δ 15 N and stem N concentration values were significantly higher in deep...... season and associated phenological delay on growth. Our findings suggest that an increase in winter precipitation in the High Arctic, as predicted by climate models, has the potential to alter the growth and ecophysiology of evergreen shrub C. tetragona through changes in plant mineral nutrition and...... winter snow depth on shrub growth and ecophysiology by measuring stem length and stem hydrogen ( δ2H), carbon ( δ13C), nitrogen ( δ15N) and oxygen ( δ18O) isotopic composition of the circumarctic evergreen dwarf shrub Cassiope tetragona growing in high-arctic Svalbard, Norway. Measurements were carried...

  11. A note about new and rarely recorded taxa of the genus Cladonia from the Arctic island Spitsbergen (Svalbard

    Directory of Open Access Journals (Sweden)

    Piotr Osyczka

    2011-04-01

    Full Text Available The paper is based on field studies dealing with the lichen genus Cladonia Hill ex P. Browne (Cladoniaceae carried out by the author in the region of Spitsbergen in 2002 as well as taxonomical work and revision of herbarium material, collected during several earlier Polish polar expeditions to this part of the Arctic. As the result not reported so far from the island species Cladonia stygia (Fr. Ruoss, C. trassii Ahti, C. verticillata (Hoffm. Schaer. have been determined. Besides, the presence of very rarely recorded taxa C. crispata var. cetrariiformis (Delise Vain., C. merochlorophaea Asahina and Cladonia symphycarpia (Flörke Fr. is confirmed and their new localities are given. Furthermore, the presence of C. coccifera s.str. is also substantiated.

  12. Snow cover and extreme winter warming events control flower abundance of some, but not all species in high arctic Svalbard

    DEFF Research Database (Denmark)

    Semenchuk, Philipp R.; Elberling, Bo; Cooper, Elisabeth J.

    2013-01-01

    years, during which we experienced two extreme winter warming events. Most species were resistant to snow cover increase, but two species reduced flower abundance due to shortened growing seasons. Cassiope tetragona responded strongly with fewer flowers in deep snow regimes during years without extreme...... events, while Stellaria crassipes responded partly. Snow pack thickness determined whether winter warming events had an effect on flower abundance of some species. Warming events clearly reduced flower abundance in shallow but not in deep snow regimes of Cassiope tetragona, but only marginally for Dryas...... frequent extreme winter warming events. Flower production of many Arctic plants is dependent on melt out timing, since season length determines resource availability for flower preformation. We erected snow fences to increase snow depth and shorten growing season, and counted flowers of six species over 5...

  13. Shifts in Identity and Activity of Methanotrophs in Arctic Lake Sediments in Response to Temperature Changes

    OpenAIRE

    He, Ruo; Wooller, Matthew J; Pohlman, John W.; Quensen, John; Tiedje, James M.; Leigh, Mary Beth

    2012-01-01

    Methane (CH4) flux to the atmosphere is mitigated via microbial CH4 oxidation in sediments and water. As arctic temperatures increase, understanding the effects of temperature on the activity and identity of methanotrophs in arctic lake sediments is important to predicting future CH4 emissions. We used DNA-based stable-isotope probing (SIP), quantitative PCR (Q-PCR), and pyrosequencing analyses to identify and characterize methanotrophic communities active at a range of temperatures (4°C, 10°...

  14. Microseismic monitoring of a future CO2 storage site in the Arctic (Svalbard) - Suppression and utilization of seismic noise

    Science.gov (United States)

    Kühn, Daniela; Albaric, Julie; Harris, Dave; Oye, Volker; Hillers, Gregor; Brenguier, Florent; Ohrnberger, Matthias; Braathen, Alvar; Olaussen, Snorre

    2014-05-01

    Since 2007, CO2 Capture and Storage (CCS) research has been carried out in the Longyearbyen CO2 lab (hosted by University Centre in Svalbard, UNIS, and UNIS CO2-lab AS). Due to its remoteness, the CO2 lab injection site presents a unique opportunity to demonstrate the entire CO2 value chain based on the closed energy system including coal mines, a coal fuelled power plant and geological structures suited for CO2 sequestration. The reservoir at a depth of 670 - 970 m consists of Triassic and Jurassic sandstone formations. The primary caprock is formed by a 400 - 500 m thick layer of organic rich shale, whereas the impermeable near-surface layer of permafrost currently constitutes a secondary top-seal. Eight wells were drilled down to a maximum of about 1000 m depth in order to analyse composition and structure of the reservoir, to perform injection tests and to deploy instruments close to the reservoir. Although the reservoir sandstone exhibits a low primary permeability and porosity, injection test campaigns demonstrate a good injectivity, indicating an unconventional reservoir strongly impacted by tectonic fractures. To perform microseismic monitoring, a high-frequency geophone network surrounding the injection well has been established. During the first water injection in 2010, a microseismic event (M ~ 1) was recorded and located close to the injection well, followed by a series of 7 aftershocks identified using a matched filter method. Later injection tests did not generate any detectable microseismic events; nevertheless, pressure and flow rate showed a pattern characteristic for fracture opening, potentially indicating "aseismic" fracture propagation or slow slip. Prior to data analysis, signals resulting from local mining operations, degassing, icequakes and regional earthquakes have to be separated from seismicity induced by (water) injection. In addition, recorded signals are strongly corrupted by electronic noise. Especially for correlation and stacking

  15. Snow cover and extreme winter warming events control flower abundance of some, but not all species in high arctic Svalbard

    Science.gov (United States)

    Semenchuk, Philipp R; Elberling, Bo; Cooper, Elisabeth J

    2013-01-01

    Abstract The High Arctic winter is expected to be altered through ongoing and future climate change. Winter precipitation and snow depth are projected to increase and melt out dates change accordingly. Also, snow cover and depth will play an important role in protecting plant canopy from increasingly more frequent extreme winter warming events. Flower production of many Arctic plants is dependent on melt out timing, since season length determines resource availability for flower preformation. We erected snow fences to increase snow depth and shorten growing season, and counted flowers of six species over 5 years, during which we experienced two extreme winter warming events. Most species were resistant to snow cover increase, but two species reduced flower abundance due to shortened growing seasons. Cassiope tetragona responded strongly with fewer flowers in deep snow regimes during years without extreme events, while Stellaria crassipes responded partly. Snow pack thickness determined whether winter warming events had an effect on flower abundance of some species. Warming events clearly reduced flower abundance in shallow but not in deep snow regimes of Cassiope tetragona, but only marginally for Dryas octopetala. However, the affected species were resilient and individuals did not experience any long term effects. In the case of short or cold summers, a subset of species suffered reduced reproductive success, which may affect future plant composition through possible cascading competition effects. Extreme winter warming events were shown to expose the canopy to cold winter air. The following summer most of the overwintering flower buds could not produce flowers. Thus reproductive success is reduced if this occurs in subsequent years. We conclude that snow depth influences flower abundance by altering season length and by protecting or exposing flower buds to cold winter air, but most species studied are resistant to changes. Winter warming events, often

  16. Is historical human presence an appropriate indicator for long-term anthropogenic pressure on Svalbard ecosystems?

    NARCIS (Netherlands)

    Kruse, Frigga

    2015-01-01

    The Arctic is not a pristine wilderness. Spitsbergen (now Svalbard) in the European Arctic was first documented in 1596. Since then, newcomers to the unpeopled archipelago have engaged in whaling, sealing, and hunting and trapping. This study investigates if historical human presence in Svalbard can

  17. Vertical distribution of methane oxidation and methanotrophic response to elevated methane concentrations in stratified waters of the Arctic fjord Storfjorden (Svalbard, Norway

    Directory of Open Access Journals (Sweden)

    S. Mau

    2013-10-01

    Full Text Available The bacterially mediated aerobic methane oxidation (MOx is a key mechanism in controlling methane (CH4 emissions from the world's oceans to the atmosphere. In this study, we investigated MOx in the Arctic fjord Storfjorden (Svalbard by applying a combination of radio-tracer-based incubation assays (3H-CH4 and 14C-CH4, stable C-CH4 isotope measurements, and molecular tools (16S rRNA gene Denaturing Gradient Gel Electrophoresis (DGGE fingerprinting, pmoA- and mxaF gene analyses. Storfjorden is stratified in the summertime with melt water (MW in the upper 60 m of the water column, Arctic water (ArW between 60 and 100 m, and brine-enriched shelf water (BSW down to 140 m. CH4 concentrations were supersaturated with respect to the atmospheric equilibrium (about 3–4 nM throughout the water column, increasing from ∼20 nM at the surface to a maximum of 72 nM at 60 m and decreasing below. MOx rate measurements at near in situ CH4 concentrations (here measured with 3H-CH4 raising the ambient CH4 pool by −1 at 60 m, followed by a decrease in the deeper ArW/BSW. In contrast, rate measurements with 14C-CH4 (incubations were spiked with ∼450 nM of 14C-CH4, providing an estimate of the CH4 oxidation at elevated concentration showed comparably low turnover rates (−1 at 60 m, and peak rates were found in ArW/BSW at ∼100 m water depth, concomitant with increasing 13C values in the residual CH4 pool. Our results indicate that the MOx community in the surface MW is adapted to relatively low CH4 concentrations. In contrast, the activity of the deep-water MOx community is relatively low at the ambient, summertime CH4 concentrations but has the potential to increase rapidly in response to CH4 availability. A similar distinction between surface and deep-water MOx is also suggested by our molecular analyses. The DGGE banding patterns of 16S rRNA gene fragments of the surface MW and deep water were clearly different. A DGGE band related to the known type I MOx

  18. Paleomagnetic Studies of Marine Sediments for Evaluation of Sedimentation Rates on the Mendeleev Ridge, Arctic Ocean

    Science.gov (United States)

    Elkina, D.

    2014-12-01

    Nowadays the Arctic Ocean is an area of higher scientific interest. Investigation of composition, genesis, sources and source areas of marine sediments is necessary for a gain of geological knowledge and geo-engineering development of the region. One should note that the dating issue in the Arctic Ocean is a challenge by itself. However, magnetostratigraphy can offer a powerful stratigraphic tool applying to marine sediments here. The 6-meters length core was retrieved from the Mendeleev Ridge in 2012 and subjected to paleomagnetic studies. The examined core was revealed to dominate by normal polarity up to 123 cm below seafloor (cmbsf) and assigned there to the Brunhes polarity chron of the geomagnetic field (0.78 Ma). Then prevalence of reverse polarity persists up to 394-397 cmbsf, assigned to Matuyama age, and short positive intervals are believed to be subchrons of normal polarity. Change from reverse to normal polarity at 394-397 cmbsf is considered as the Matuyama - Gauss (2.58 Ma) boundary and is traced up to 530-531 cmbsf including one short reversal. After this depth a drop back to reverse polarity is ascribed to the beginning of the Gilbert polarity chron (3.58 Ma). The resultant magnetostratigraphy is presented on Figure 1. The stepwise alternating field demagnetization and demagnetization by heating were performed to remove viscous overprints and then to define component magnetization directions. Spikes of natural remanent magnetization intensity and magnetic susceptibility are discovered near almost all assigned chron boundaries, and it may act as an independent factor for determination of polarity boundaries. Anisotropy of magnetic susceptibility is also considered in order to find out additional peculiarities of the sedimentation. The relative abundance of shallow inclinations at least implies the existence of secondary processes, which may have altered the paleomagnetic record. The mean sedimentation rates on the Mendeleev Ridge do not exceed 1

  19. Mineralogical study of surface sediments in the western Arctic Ocean and their implications for material sources

    Institute of Scientific and Technical Information of China (English)

    DONG Linsen; SHI Xuefa; LIU Yanguang; FANG Xisheng; CHEN Zhihua; WANG Chunjuan; ZOU Jianjun; HUANG Yuanhui

    2014-01-01

    Mineralogical analysis was performed on bulk sediments of 79 surface samples using X-ray diffraction. The analytical results, combined with data on ocean currents and the regional geological background, were used to investigate the mineral sources. Mineral assemblages in sediments and their distribution in the study area indicate that the material sources are complex. (1) Feldspar is abundant in the sediments of the middle Chukchi Sea near the Bering Strait, originating from sediments in the Anadyr River carried by the Anadyr Current. Sediments deposited on the western side of the Chukchi Sea are rich in feldspar. Compared with other areas, sediments in this region are rich in hornblende transported from volcanic and sedimentary rocks in Siberia by the Anadyr Stream and the Siberian Coastal Current. Sediments in the eastern Chukchi Sea are rich in quartz sourced from sediments of the Yukon and Kuskokwim rivers carried by the Alaska Coastal Current. Sediments in the northern Chukchi Sea are rich in quartz and carbonates from the Mackenzie River sediments. (2) Sediments of the southern and central Canada Basin contain little calcite and dolomite, mainly due to the small impact of the Beaufort Gyre carrying carbonates from the Canadian Arctic Islands. Compared with other areas, the mica content in the region is high, implying that the Laptev Sea is the main sediment source for the southern and central Canada Basin. In the other deep sea areas, calcite and dolomite levels are high caused by the input of large amounts of sediment carried by the Beaufort Gyre from the Canadian Arctic Islands (Banks and Victoria). The Siberian Laptev Sea also provides small amounts of sediment for this region. Furthermore, the Atlantic mid-water contributes some fine-grained material to the entire deep western Arctic Ocean.

  20. Methane-derived carbon flow through microbial communities in arctic lake sediments.

    Science.gov (United States)

    He, Ruo; Wooller, Matthew J; Pohlman, John W; Tiedje, James M; Leigh, Mary Beth

    2015-09-01

    Aerobic methane (CH4 ) oxidation mitigates CH4 release and is a significant pathway for carbon and energy flow into aquatic food webs. Arctic lakes are responsible for an increasing proportion of global CH4 emissions, but CH4 assimilation into the aquatic food web in arctic lakes is poorly understood. Using stable isotope probing (SIP) based on phospholipid fatty acids (PLFA-SIP) and DNA (DNA-SIP), we tracked carbon flow quantitatively from CH4 into sediment microorganisms from an arctic lake with an active CH4 seepage. When 0.025 mmol CH4 g(-1) wet sediment was oxidized, approximately 15.8-32.8% of the CH4 -derived carbon had been incorporated into microorganisms. This CH4 -derived carbon equated to up to 5.7% of total primary production estimates for Alaskan arctic lakes. Type I methanotrophs, including Methylomonas, Methylobacter and unclassified Methylococcaceae, were most active at CH4 oxidation in this arctic lake. With increasing distance from the active CH4 seepage, a greater diversity of bacteria incorporated CH4 -derived carbon. Actinomycetes were the most quantitatively important microorganisms involved in secondary feeding on CH4 -derived carbon. These results showed that CH4 flows through methanotrophs into the broader microbial community and that type I methanotrophs, methylotrophs and actinomycetes are important organisms involved in using CH4 -derived carbon in arctic freshwater ecosystems. PMID:25581131

  1. Thermophilic anaerobes in arctic marine sediments induced to mineralize complex organic matter at high temperature

    DEFF Research Database (Denmark)

    Hubert, Casey; Arnosti, Carol; Brüchert, Volker;

    2010-01-01

    well as with the addition of freeze-dried Spirulina or individual high-molecular-weight polysaccharides. During 50°C incubation experiments, Arctic thermophiles catalysed extensive mineralization of the organic matter via extracellular enzymatic hydrolysis, fermentation and sulfate reduction. This high...... temperature-induced food chain mirrors sediment microbial processes occurring at cold in situ temperatures (near 0°C), yet it is catalysed by a completely different set of microorganisms. Using sulfate reduction rates (SRR) as a proxy for organic matter mineralization showed that differences in organic matter......Marine sediments harbour diverse populations of dormant thermophilic bacterial spores that become active in sediment incubation experiments at much higher than in situ temperature. This response was investigated in the presence of natural complex organic matter in sediments of two Arctic fjords, as...

  2. Hydrological response of a High-Arctic catchment to changing climate over the past 35 years: a case study of Bayelva watershed, Svalbard

    OpenAIRE

    Nowak, Aga; Hodson, Andy

    2013-01-01

    Our study considers climate change and its influence upon the hydrology and water balance of the glacierized Bayelva watershed in Svalbard. We find that changes are most noticeable within the last 10 years, when winters have become warmer and wetter. The change is most significant during the shoulder months, especially September, when the transition from summer ablation to winter accumulation is taking place. Winter rainfalls, when extreme, produce ground icings and runoff outside the summer ...

  3. Identification of functionally active aerobic methanotrophs in sediments from an arctic lake using stable isotope probing

    Science.gov (United States)

    He, Ruo; Wooller, Matthew J.; Pohlman, John W.; Catranis, Catharine; Quensen, John; Tiedje, James M.; Leigh, Mary Beth

    2012-01-01

    Arctic lakes are a significant source of the greenhouse gas methane (CH4), but the role that methane oxidizing bacteria (methanotrophs) play in limiting the overall CH4 flux is poorly understood. Here, we used stable isotope probing (SIP) techniques to identify the metabolically active aerobic methanotrophs in upper sediments (0–1 cm) from an arctic lake in northern Alaska sampled during ice-free summer conditions. The highest CH4 oxidation potential was observed in the upper sediment (0–1 cm depth) with 1.59 μmol g wet weight-1 day-1 compared with the deeper sediment samples (1–3 cm, 3–5 cm and 5–10 cm), which exhibited CH4 oxidation potentials below 0.4 μmol g wet weight-1 day-1. Both type I and type II methanotrophs were directly detected in the upper sediment total communities using targeted primer sets based on 16S rRNA genes. Sequencing of 16S rRNA genes and functional genes (pmoA and mxaF) in the 13C-DNA from the upper sediment indicated that type I methanotrophs, mainly Methylobacter, Methylosoma, Methylomonas and Methylovulum miyakonense, dominated the assimilation of CH4. Methylotrophs, including the genera Methylophilus and/or Methylotenera, were also abundant in the 13CDNA. Our results show that a diverse microbial consortium acquired carbon from CH4 in the sediments of this arctic lake.

  4. High-Resolution 3D-Seismic Investigations Indicate Focused Fluid Flow Systems in Hydrated Sediments at the Vestnesa Ridge off the W-Svalbard Margin.

    Science.gov (United States)

    Petersen, C.; Buenz, S.; Hustoft, S.; Mienert, J.

    2007-12-01

    High-resolution seismic data were acquired using the 3D seismic P-Cable system of the University of Tromsoe to investigate how the fluid flow penetrates gas hydrate systems of the Vestnesa Ridge. The ridge represents a current-controlled sediment drift on the continental margin offshore western Svalbard. The survey area is located at the northwestern part of the Vestnesa Ridge and centered at the ridge crest that resembles an anticline in a water depth of 1250-1320 m. The seafloor morphology at the crest is characterized by an abundance of pockmarks with a diameter between 50-500 m indicating recent fluid flow activity. Since the area is within the gas hydrate stability zone (GHSZ), it is an ideal site to understand where and how fluids escape through a hydrated sediment drift. 35 reflection seismic profiles with a spacing of about 40-60 m were shot resulting in a seismic cube covering an area of approximately 22 km2. In addition, regional single channel streamer (SCS) seismic lines were acquired across the ridge perpendicular to the crest to connect the 3D area with the regional structural setting. The seismic data provide images of the subsurface to about 500 ms TWT (two-way time) below the seafloor (bsf), where gas accumulations cause acoustic attenuations that hinder deeper acoustic signal penetration. The well-stratified sediments exhibit a bottom simulating reflector (BSR) at about 200 ms TWT bsf at the base of the GHSZ. The BSR is difficult to identify due to the stratification, but it is accompanied by the onset of an ubiquitous band of strong reflectivity indicating free gas accumulation zones beneath the GHSZ. Fluid flow activity is evident from a link between gas accumulations (bright spots), gas wipeouts and disturbed reflectivity in the seismic data. These features are observed not only beneath the pockmark structures, but also in the sediment without seafloor expressions of fluid venting. The fluid source might be related to deep tectonic processes at

  5. Sediment Nitrification, Denitrification, and Nitrous Oxide Production in a Deep Arctic Lake †

    OpenAIRE

    Klingensmith, K. M.; Alexander, V.

    1983-01-01

    We used a combination of 15N tracer methods and a C2H2 blockage technique to determine the role of sediment nitrification and denitrification in a deep oligotrophic arctic lake. Inorganic nitrogen concentrations ranged between 40 and 600 nmol · cm−3, increasing with depth below the sediment-water interface. Nitrate concentrations were at least 10 times lower, and nitrate was only detectable within the top 0 to 6 cm of sediment. Eh and pH profiles showed an oxidized surface zone underlain by m...

  6. Bacterial and archaeal community structures in the Arctic deep-sea sediment

    Institute of Scientific and Technical Information of China (English)

    LI Yan; LIU Qun; LI Chaolun; DONG Yi; ZHANG Wenyan; ZHANG Wuchang; XIAO Tian

    2015-01-01

    Microbial community structures in the Arctic deep-sea sedimentary ecosystem are determined by organic matter input, energy availability, and other environmental factors. However, global warming and earlier ice-cover melting are affecting the microbial diversity. To characterize the Arctic deep-sea sediment microbial diversity and its rela-tionship with environmental factors, we applied Roche 454 sequencing of 16S rDNA amplicons from Arctic deep-sea sediment sample. Both bacterial and archaeal communities’ richness, compositions and structures as well as tax-onomic and phylogenetic affiliations of identified clades were characterized. Phylotypes relating to sulfur reduction and chemoorganotrophic lifestyle are major groups in the bacterial groups;while the archaeal community is domi-nated by phylotypes most closely related to the ammonia-oxidizing Thaumarchaeota (96.66%) and methanogenic Euryarchaeota (3.21%). This study describes the microbial diversity in the Arctic deep marine sediment (>3 500 m) near the North Pole and would lay foundation for future functional analysis on microbial metabolic processes and pathways predictions in similar environments.

  7. Fram-2014/2015: A 400 Day Investigation of the Arctic's Oldest Sediments over the Alpha Ridge with a Research Hovercraft

    Science.gov (United States)

    Hall, J. K.; Kristoffersen, Y.

    2014-12-01

    The thickest multi-year ice in the Arctic covers a secret. Four short cores raised from the Alpha Ridge in the 1970s and 1980s from drift stations T-3 and CESAR showed ages between 45 and 76 my. The reason for these old ages became clear when examination of legacy seismic data from T-3 showed that in some places up to 500 m of sediments had been removed within an area of some 200 by 600 km, presumably by an impact of asteroid fragments. To investigate the impact area, the authors conceived an innovative research platform in 2007. Named the R/H SABVABAA, this 12m by 6m hovercraft has been home-based in Svalbard since June 2008. During the following 6 years the craft and its evolving innovative light-weight equipment have made 18 trips to the summer ice pack, traveling some 4410 km over ice during some six months of scientific investigations. An opportunity to get a lift to this area, some 1500 km from Svalbard, came in a 2011 invitation to join AWI's icebreaker POLARSTERN in its ARK-XXVIII/4 expedition departing Tromsö August 5, 2014. The 400 day drift will be the first wintering over, ever, of a mobile research platform with geophysical, geological, and oceanographic capabilities. The Arctic ice pack continually moves due to winds and currents. While at the main camp, observations will consist of marine geophysics (seismic profiling with four element CHIRP, a 20 in³ airgun with single hydrophone, as well as 12 kHz bathymetry and 200 kHz sounding of the deep scattering layer), marine geology (coring with a hydrostatically-boosted 3 or 6 m corer; bottom photography; and two rock dredges), and oceanography. Deployed away from the camp, four sonobuoys will allow 3-D seismic acquisition. Access to the depths below the ice is via a hydraulic capstan winch, with 6500 m of Kevlar aramid fiber rope with 2.8 ton breaking strength. Ice thickness monitoring of the local 100 km² will be made with the craft's EM-31 probe when away from the camp, moving to choice locations for

  8. Shifts in identity and activity of methanotrophs in arctic lake sediments in response to temperature changes

    Science.gov (United States)

    He, Ruo; Wooller, Matthew J.; Pohlman, John W.; Quensen, John; Tiedje, James M.; Leigh, Mary Beth

    2012-01-01

    Methane (CH4) flux to the atmosphere is mitigated via microbial CH4 oxidation in sediments and water. As arctic temperaturesincrease, understanding the effects of temperature on the activity and identity of methanotrophs in arctic lake sediments is importantto predicting future CH4 emissions. We used DNA-based stable-isotope probing (SIP), quantitative PCR (Q-PCR), andpyrosequencing analyses to identify and characterize methanotrophic communities active at a range of temperatures (4°C, 10°C,and 21°C) in sediments (to a depth of 25 cm) sampled from Lake Qalluuraq on the North Slope of Alaska. CH4 oxidation activitywas measured in microcosm incubations containing sediments at all temperatures, with the highest CH4 oxidation potential of37.5 mol g1 day1 in the uppermost (depth, 0 to 1 cm) sediment at 21°C after 2 to 5 days of incubation. Q-PCR of pmoA and ofthe 16S rRNA genes of type I and type II methanotrophs, and pyrosequencing of 16S rRNA genes in 13C-labeled DNA obtained bySIP demonstrated that the type I methanotrophs Methylobacter, Methylomonas, and Methylosoma dominated carbon acquisitionfrom CH4 in the sediments. The identity and relative abundance of active methanotrophs differed with the incubation temperature.Methylotrophs were also abundant in the microbial community that derived carbon from CH4, especially in the deeper sediments(depth, 15 to 20 cm) at low temperatures (4°C and 10°C), and showed a good linear relationship (R0.82) with the relativeabundances of methanotrophs in pyrosequencing reads. This study describes for the first time how methanotrophiccommunities in arctic lake sediments respond to temperature variations.

  9. The response of methane hydrate beneath the seabed offshore Svalbard to ocean warming during the next three centuries

    OpenAIRE

    Marín-Moreno, Héctor; Minshull, Timothy A.; Westbrook, Graham K.; Sinha, Bablu; Sarkar, Sudipta

    2013-01-01

    Methane is a potent greenhouse gas and large-scale rapid release of methane from hydrate may have contributed to past abrupt climate change inferred from the geological record. The discovery in 2008 of over 250 plumes of methane gas escaping from the seabed of the West Svalbard continental margin at ~400 m water depth (mwd) suggests that hydrate is dissociating in the present-day Arctic. Here we model the dynamic response of hydrate-bearing sediments over a period of 2300 years and investigat...

  10. 1st Science-Industry platform on expedition cruise tourism in Svalbard

    NARCIS (Netherlands)

    Lamers, M.A.J.; Olsen, J.; Hovelsrud, G.; Lang, I.; Jorgensen, F.

    2014-01-01

    The interest in Svalbard as a cruise tourism destination has increased gradually over the past decades, leading to a range of opportunities and challenges for marine and terrestrial ecosystems, communities, and regulatory systems on Svalbard and elsewhere in the Arctic (e.g. Greenland, Iceland, Russ

  11. Short-lived high-amplitude cooling on Svalbard during the Dark Ages

    Science.gov (United States)

    van der Bilt, Willem; D`Andrea, William; Bakke, Jostein; Balascio, Nicholas; Werner, Johannes; Hoek, Wim

    2016-04-01

    As the paradigm of a stable Holocene climate has shifted, an increasing number of high-resolution proxy timeseries reveal dynamic conditions, characterized by high-amplitude climate shifts. Some of these events occurred during historical times and allow us to study the interaction between environmental and cultural change, providing valuable lessons for the near future. These include the Dark Ages Cold Period (DACP) between 300 and 800 AD, a period marked by political upheaval and climate instability that remains poorly investigated. Here, we present two temperature reconstructions from the High Arctic Svalbard Archipelago. To this end, we applied the established alkenone-based UK37 paleothermometer on sediments from two lakes on western Spitsbergen, Lake Hajeren and Lake Hakluyt. The Arctic is presently warming twice as fast as the global average and proxy data as well as model simulations suggest that this amplified response is characteristic for regional climate. The Arctic therefore provides a uniquely sensitive environment to study relatively modest climate shifts, like the DACP, that may not be adequately captured at lower-latitude sites. Owing to undisturbed sediments, a high sampling resolution and robust chronological control, the presented reconstructions resolve the attendant sub-centennial-scale climate shifts. Our findings suggest that the DACP marks a cold spell within the cool Neoglacial period, which started some 4 ka BP on Svalbard. Close investigation reveals a distinct temperature minimum around 500 AD that is reproduced in another alkenone-based temperature reconstruction from a nearby lake. At ± 1.75 °C, cooling underlines the sensitivity of Arctic climate as well as the magnitude of the DACP.

  12. Depositional environment, ichnological features and oxygenation of Permian to earliest Triassic marine sediments in central Spitsbergen, Svalbard

    OpenAIRE

    Uchman, Alfred; Hanken, Nils-Martin; Nielsen, Jesper Kresten; Piasecki, Stefan; Grundvåg, Sten-Andreas

    2016-01-01

    Late Early Permian–lowermost Triassic carbonate, siliceous (spiculites) and clastic marine sediments in the Marmierfjellet area (Isfjorden, central Spitsbergen) contain a relatively diverse and abundant trace fossil assemblage providing important information about the depositional processes. The Vøringen Member (Late Artinskian–Kungurian) of the Kapp Starostin Formation (Late Artinskian–? Changhsingian) contains trace fossils (Nereites, Phycosiphon, Zoophycos and Arenicolites—common in tempes...

  13. Acetate, lactate, propionate, and isobutyrate as electron donors for iron and sulfate reduction in Arctic marine sediments, Svalbard

    DEFF Research Database (Denmark)

    Finke, Niko; Vandieken, Verona; Jørgensen, Bo Barker

    2007-01-01

    oxidized (0-2 cm) and the reduced (5-9 cm) zone. In the 0-2 cm layer, 2/3 of the mineralization could be attributed to sulfate reduction and 1/3 to iron reduction. In the 5-9 cm layer, sulfate reduction was the sole mineralization process. Acetate and lactate turnover rates were measured by radiotracer....... Inhibition of sulfate reduction with selenate resulted in the accumulation of acetate, propionate, and isobutyrate. The acetate turnover rates determined by radiotracer and accumulation after inhibition were similar. VFA turnover accounted for 21% and 52% of the mineralization through sulfate reduction in...... the 0-2 and 5-9 cm layer, respectively. Acetate and lactate turnover in the inhibited 0-2 cm slurry was attributed to iron reduction and accounted for 10% and 2% of the iron reduction. Therefore, 88% and 79% of the iron and sulfate reduction in the 0-2 cm layer, respectively, must be fueled by...

  14. Microbial community structure and ecology of subglacial sediments in two polythermal Svalbard glaciers characterized by epifluorescence microscopy and PLFA

    Czech Academy of Sciences Publication Activity Database

    Kaštovská, Klára; Stibal, Marek; Šabacká, Marie; Černá, B.; Šantrůčková, H.; Elster, Josef

    2007-01-01

    Roč. 30, č. 3 (2007), s. 277-287. ISSN 0722-4060. [International Conference on Alpine and Polar Microbiology. Innsbruck, 27.3.2006-30.3.2006] R&D Projects: GA AV ČR(CZ) KJB6005409; GA ČR(CZ) GP206/03/P024 Institutional research plan: CEZ:AV0Z60170517; CEZ:AV0Z60050516 Keywords : subglacial sediment * microbial community * PLFA Subject RIV: EH - Ecology, Behaviour Impact factor: 1.734, year: 2007

  15. Biomarkers of Canadian High Arctic Litoral Sediments for Assessment of Organic Matter Sources and Degradation

    Science.gov (United States)

    Pautler, B. G.; Austin, J.; Otto, A.; Stewart, K.; Lamoureux, S. F.; Simpson, M. J.

    2009-05-01

    Carbon stocks in the High Arctic are particularly sensitive to global climate change, and investigation of variations in organic matter (OM) composition is beneficial for the understanding of the alteration of organic carbon under anticipated future elevated temperatures. Molecular-level characterization of solvent extractable compounds and CuO oxidation products of litoral sedimentary OM at the Cape Bounty Arctic Watershed Observatory in the Canadian Arctic Archipelago was conducted to determine the OM sources and decomposition patterns. The solvent extracts contained a series of aliphatic lipids, steroids and one triterpenoid primarily of higher plant origin and new biomarkers, iso- and anteiso-alkanes originating from cerastium arcticum (Arctic mouse-ear chickweed, a native angiosperm) were discovered. Carbon preference index (CPI) values for the n-alkanes, n-alkanols and n-alkanoic acids suggests that the OM biomarkers result from fresh material input in early stage of degradation. The CuO oxidation products were comprised of benzyls, lignin phenols and short-chain diacids and hydroxyacids. High abundance of terrestrial OM biomarkers observed at sites close to the river inlet suggests fluvial inputs as an important pathway to deliver OM into the lake. The lignin phenol vegetation index (LPVI) also suggests that the OM origin is mostly from non-woody angiosperms. A relatively high degree of lignin alteration in the litoral sediments is evident from the abundant ratio of acids and aldehydes of the vanillyl and syringyl monomers. This suggests that the lignin contents have been diagenetically altered as the result of a long residence time in this ecosystem. The molecular-level characterization of litoral sedimentary OM in Canadian High Arctic region provides insight into current OM composition,potential responses to future disturbances and the biogeochemical cycling of carbon in the Arctic.

  16. The distribution of radiocesium and plutonium in sea ice-entrained arctic sediments in relation to potential sources and sinks

    International Nuclear Information System (INIS)

    Gamma counting of a range of grain size fractions of sediments entrained in Arctic Ocean sea ice indicate that the wide range of radiocesium activities that are observed in bulk samples are primarily a function of the geographical origin of the sediment, rather than mineral composition, or physical processes that increase the content of fine clays in sediments. Plutonium isotope ratios (240Pu:239Pu) of sea ice sediments are consistent with an ultimate origin of the plutonium from bomb fallout (240Pu:239Pu=similar0·18), and these sediment ratios differ significantly in plutonium isotope ratios from deep sea sediments of the Arctic Ocean. Much lower plutonium activities were observed in deep sea sediments relative to the sea ice entrained sediments. These differences in isotopic ratios indicate that on decadal scales, sedimentation of bomb fallout plutonium is not the sole source of plutonium to deep Arctic Ocean sediments. The large differences in total plutonium activity between some of the sea ice entrained sediments and all of the deep Arctic Ocean sediments also suggest that the total flux of plutonium from sea ice entrained sediments to the deep sea may be relatively small. Radiocesium activity in the sea ice entrained sediments is well correlated with total plutonium abundance, but the best-fit regression line does not pass through the origin, indicating that a small secondary source of cesium (3 to 9 Bq kg-1 dry weight) that is free of plutonium may contribute to the radiocesium activity observed in sediments entrained in Arctic Ocean sea ice. Based upon observations of carbon:nitrogen weight/weight ratios in excess of 20 in the organic carbon fraction, together with δ13C values less than -23%, several of the sea ice entrained sediments show indications of estuarine origin. However, these specific samples typically have low radionuclide burdens. Consideration of the low smectite content (sediments and prevailing

  17. The Svalbard shoreline oilspill field trials

    International Nuclear Information System (INIS)

    The 1997 Svalbard shoreline oil spill field experiment was conducted to quantify the effectiveness of different in situ shoreline treatment options that are commonly used to accelerate natural oil removal processes on mixed coarse sediment beaches. Three experimental sites were chosen near the mining town of Sveagruva on Spitsbergen, the largest island in Svalbard, Norway. 5,500 litres of an intermediate fuel oil, was applied directly to a 3 m wide area of the upper intertidal zone sediment surface in a controlled and uniform manner. Full scale treatments began one week after oiling to allow for wave and tidal washing and stabilization of the oiled zone. Five treatment options were used: (1) sediment relocation, (2) tilling (or aeration); (3) bioremediation, (4) tilling combined with bioremediation, and (5) natural recovery. The sediment was treated in the same way as in an actual response operation. The trials were successful from both an operational and experimental point of view. 14 refs., 2 tabs., 9 figs

  18. Depositional environment, ichnological features and oxygenation of Permian to earliest Triassic marine sediments in central Spitsbergen, Svalbard

    Directory of Open Access Journals (Sweden)

    Alfred Uchman

    2016-05-01

    Full Text Available Late Early Permian–lowermost Triassic carbonate, siliceous (spiculites and clastic marine sediments in the Marmierfjellet area (Isfjorden, central Spitsbergen contain a relatively diverse and abundant trace fossil assemblage providing important information about the depositional processes. The Vøringen Member (Late Artinskian–Kungurian of the Kapp Starostin Formation (Late Artinskian–? Changhsingian contains trace fossils (Nereites, Phycosiphon, Zoophycos and Arenicolites—common in tempestites typical of the proximal–archetypal Cruziana ichnofacies, which indicates lower shoreface. Nereites, Phycosiphon and Zoophycos, accompanied by other rare trace fossils, characterize the Svenskegga and Hovtinden members of the Kapp Starostin Formation. They are interpreted as the distal Cruziana ichnofacies, possibly transitional to the Zoophycos ichnofacies typical of the lower offshore zone. However, the sporadic occurrences of Arenicolites and Macaronichnus can point to episodic shallowing to upper offshore–lower shoreface. The lowest part of the Triassic Vikinghøgda Formation (Induan–Olenekian contains a very low-diverse ichnoassemblage composed of a few simple and branched forms ascribed to the impoverished Cruziana ichnofacies (lower to upper offshore environment, which is attributed to the early recovery stage after the Permian–Triassic extinction. The trace fossils and loss of primary sedimentary structures caused by intense bioturbation throughout most of the section point to generally oxygenated pore waters on the sea floor. However, some horizons, especially laminated black shales, display reduced or no bioturbational activity. These horizons also show high V/(V+Ni ratios, which indicate oxygen-depleted sediments with periods of anoxic conditions. A remarkable black shale unit deposited under anoxic and sulphidic conditions occurs at the Permian–Triassic transition.

  19. Sedimentary processes in High Arctic lakes (Cape Bounty, Melville Island, Canada): What do sediments really record?

    Science.gov (United States)

    Normandeau, Alexandre; Lamoureux, Scott; Lajeunesse, Patrick; Francus, Pierre

    2016-04-01

    Lacustrine sedimentary sequences can hold a substantial amount of information regarding paleoenvironments, hydroclimate variability and extreme events, providing critical insights into past climate change. The study of lacustrine sediments is often limited to the analysis of sediment cores from which past changes are inferred. However, studies have provided evidence that the accumulation of sediments in lacustrine basins and their distribution can be affected by a wide range of internal and external forcing mechanisms. It is therefore crucial to have a good knowledge of the factors controlling the transport and distribution of sediments in lakes prior to investigating paleoenvironmental archives. To address this knowledge gap, the Cape Bounty Arctic Watershed Observatory (CBAWO), located on southern Melville Island in the Canadian High Arctic, was initiated in 2003 as a long term monitoring site with the aim of understanding the controls over sediment transport within similar paired watersheds and lakes. The East and West lakes have been monitored each year since 2003 to document the role of hydro-climate variability on water column processes and sediment deposition. Moorings recording water electrical conductivity, temperature, density, dissolved oxygen and turbidity, as well as sediment traps were deployed during the active hydrological period (generally May-July). These data were analyzed in combination with hydrological and climatic data from the watersheds. Additionally, a high-resolution bathymetric and sub-bottom survey was completed in 2015 and allowed imaging the lake floor and sub-surface in great detail. This combination of process and lake morphological data are unique in the Arctic. The morphostratigraphic analysis reveals two highly disturbed lake floors, being widely affected by subaqueous mass movements that were triggered during the last 2000 years. Backscatter intensity maps and the presence of bedforms on each delta foresets indicate that

  20. Chemometric Analysis for Pollution Source Assessment of Harbour Sediments in Arctic Locations

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Lejon, Tore; Jensen, Pernille Erland;

    2015-01-01

    Pollution levels, pollutant distribution and potential source assessments based on multivariate analysis (chemometrics) were made for harbour sediments from two Arctic locations; Hammerfest in Norway and Sisimiut in Greenland. High levels of heavy metals were detected in addition to organic...... pollutants. Preliminary assessments based on principal component analysis (PCA) revealed different sources and pollutant distribution in the sediments of the two harbours. Tributyltin (TBT) was, however, found to originate from point source(s), and the highest concentrations of TBT in both harbours were...... indicated relation primarily to German, Russian and American mixtures in Hammerfest; and American, Russian and Japanese mixtures in Sisimiut. PCA was shown to be an important tool for identifying pollutant sources and differences in pollutant composition in relation to sediment characteristics....

  1. Hydrological response of a High-Arctic catchment to changing climate over the past 35 years: a case study of Bayelva watershed, Svalbard

    Directory of Open Access Journals (Sweden)

    Aga Nowak

    2013-08-01

    Full Text Available Our study considers climate change and its influence upon the hydrology and water balance of the glacierized Bayelva watershed in Svalbard. We find that changes are most noticeable within the last 10 years, when winters have become warmer and wetter. The change is most significant during the shoulder months, especially September, when the transition from summer ablation to winter accumulation is taking place. Winter rainfalls, when extreme, produce ground icings and runoff outside the summer period. Dependent upon summer air temperatures, these icings may either melt and produce additional runoff or persist until the following hydrological year. These processes have a direct influence upon the water budget. They represent sources of error for water-balance calculations that either ignore winter runoff events and/or assume water storage is negligible. We show that even when the watershed is underlain by permafrost and accommodates cold-based glaciers, storage can no longer be ignored. Furthermore, we find that the use of a precipitation gradient correction of 19% per 100 m, a gauge catch correction and glacier mass-balance data (for snow accumulation and icemelt runoff should be used for accurate water-balance calculations. We also find that despite sustained glacier retreat, annual runoff volume showed no trend during 1989–2010. Discharge is more variable and longer during the last decade due to the winter rainfalls. Finally, flow recession analyses reveal increasingly efficient evacuation of meltwater from the catchment and the increasing occurrence of a delayed flowpath through the glaciers’ forefield.

  2. Tetraploids do not form cushions: association of ploidy level, growth form and ecology in the High Arctic Saxifraga oppositifolia L. s. lat. (Saxifragaceae in Svalbard

    Directory of Open Access Journals (Sweden)

    Pernille Bronken Eidesen

    2013-06-01

    Full Text Available Saxifraga oppositifolia L. is a common circumpolar plant species that displays considerable morphological and genetic variation throughout its range. It is mainly diploid, but tetraploids are reported from several regions. The growth form varies from prostate to cushion-shaped, and the plant thrives in wet snow beds as well as on dry ridges. This variation has triggered the curiosity of many researchers, but as yet, no one has explained the observed morphological variation using ecological and/or genetic factors. However, the ploidy level has rarely been taken into account. This is the first study that demonstrates a significant correlation between ploidy level, ecology and growth form in S. oppositifolia. We successfully analysed 193 individuals of S. oppositifolia from 15 locations in Svalbard to investigate possible relationships among growth forms (prostrate, intermediate and cushion, ecological factors (vegetation and soil characteristics and ploidy level. Results from flow cytometry reported 106 diploids, eight triploids and 79 tetraploids. Tetraploids almost exclusively showed prostrate growth, while the diploids displayed all three growth forms, evidence that growth form is at least partly genetically determined. Our analyses of environmental and vegetation data in relation to ploidy level indicated overlapping niches, but the tetraploids showed a narrower niche, and one shifted towards more benign habitats characterized by higher pH, higher soil temperatures and higher cover of vascular plants. The latter may suggest that tetraploids are slightly better competitors, but less hardy. Thus, autopolyploidy in S. oppositifolia has expanded the ecological amplitude of this species complex.

  3. Psychrotrophic lipase producers from Arctic soil and sediment samples.

    Science.gov (United States)

    Rasol, R; Rashidah, A R; Nazuha, R Siti Nur; Smykla, J; Maznah, W O Wan; Alias, S A

    2014-01-01

    Culturable microorganisms were successfully isolated from soil and sediment samples collected in 2011 on the northern coast of Hornsund, West Spitsbergen. A total of 63 single colony isolates from three sampling sites obtained were subjected to temperature dependence study to assess whether they are obligate psychrophilic or psychrotrophic strains. From initial temperature screening, only 53 psychrotrophic isolates were selected that are capable of growing between 4-28 degrees C. The rest that were capable of tolerating higher temperatures up to 37 degrees C were not included in this study. These isolates were chosen for lipase enzyme screening confirmation with the standard plate assay of olive oil and fluorescent dye Rhodamine B. Six lipase positive isolates were also subjected for subsequent lipase enzyme plate screening on tributyrin, triolein, olive oil and palm oil agar. Lipase production by these six isolates was further assayed by using colorimetric method with palm oil and olive oil as the substrate. These isolates with promising lipase activity ranging from 20 U/ml up to 160 U/ml on palm oil and olive oil substrate were successfully identified. Molecular identification by using 16S rRNA revealed that five out of six isolates were Gram-negative Proteobacteria and the other one was a Gram-positive Actinobacteria. PMID:25033666

  4. Late Holocene Climate Change Inferred From Varved Proglacial Lake Sediments on Northeastern Baffin Island, Arctic Canada

    Science.gov (United States)

    Thomas, E. K.; Briner, J. P.; Axford, Y.

    2007-12-01

    The Arctic has a disproportionately large response to changes in radiative forcing of climate, and glaciers and arctic lacustrine ecosystems respond sensitively to these changes. Lacustrine ecosystems throughout the Arctic are undergoing rapid regime shifts, including dramatically increased primary productivity and changing aquatic floral and faunal assemblages. Our work on organic lake sediments from northeast Baffin Island shows a large increase in primary productivity, changes in insect (Chironomidae) assemblages including the disappearance of cold stenotherms, and a rise in chironomid-inferred summer water temperatures of at least 1.5°C over the past 50 years, reaching temperatures that were unprecedented in the past 5000 years. Here, we pursue the use of varve thickness, an abiotic temperature proxy, to expand our understanding of late Holocene temperature changes on northeast Baffin Island. We obtained a 14C- and 239+240Pu-dated surface core/percussion core pair from a proglacial lake. Together these cores span > 8000 years and the sediments are varved, as verified by the 239+240Pu analysis, for at least the past 700 years. Magnetic susceptibility was high during the early Holocene, decreased to near-zero values during the mid-Holocene and increased during the past 2500 years to reach the highest values seen in the record around 1000 years ago. Loss-on- ignition had an opposite trend, with the highest values in the mid-Holocene. Sedimentation rate was constant during most of the Holocene (0.03 cm yr -1) and increased during the past 1000 years to 0.05 cm yr -1. These parameters indicate that following the absence of an active glacier during the middle Holocene, glacier activity initiated ~2500 years ago and reached peak activity over the last 1000 years. Our ongoing work to obtain a varve-thickness record for at least the last 700 years, and its calibration to a nearby weather station, will be presented.

  5. Effects of sample mass and macrofossil type on radiocarbon dating of arctic and boreal lake sediments

    Energy Technology Data Exchange (ETDEWEB)

    Oswald, W W; Anderson, P M; Brown, T A; Brubaker, L B; Hu, F S; Lozhkin, A V; Tinner, W; Kaltenrieder, P

    2006-05-29

    Dating lake sediments by accelerator mass spectrometry (AMS) {sup 14}C analysis of plant macrofossils overcomes one of the main problems associated with dating bulk sediment samples, the presence of old organic matter. Even so, many AMS dates from arctic and boreal sites appear to misrepresent the age of the sediment. To understand the nature of these apparent dating anomalies better, we conducted a series of {sup 14}C dating experiments using samples from Alaskan and Siberian lake-sediment cores. First, to test whether our analytical procedures introduced a sample-mass bias, we obtained {sup 14}C dates for different-sized pieces of single woody macrofossils. In these sample-mass experiments, sized statistically equivalent ages were found for samples as small as 0.05 mg C. Second, to assess whether macrofossil type influenced dating results, we conducted sample-type experiments in which {sup 14}C dates were obtained for different macrofossil types sieved from the same depth in the sediment. We dated materials from multiple levels in sediment cores from Upper Capsule Lake (North Slope, northern Alaska) and Grizzly Lake (Copper River Basin, southern Alaska), and from single depths in other records from northern Alaska. In several of the experiments there were significant discrepancies between dates for different plant tissues, and in most cases wood and charcoal were older than other macrofossil types, usually by several hundred years. This pattern suggests that {sup 14}C dates for woody macrofossils may misrepresent the age of the sediment by centuries, perhaps due to their longer terrestrial residence time and the potential in-built age of long-lived plants. This study identifies why some {sup 14}C dates appear to be inconsistent with the overall age-depth trend of a lake-sediment record, and it may guide the selection of {sup 14}C samples in future studies.

  6. Microbial diversity in oiled and un-oiled shoreline sediments in the Norwegian Arctic

    International Nuclear Information System (INIS)

    Field trials were conducted at an oiled shoreline on the island of Spitsbergen to examine the effect of nutrient addition on the metabolic status, potential for aromatic hydrocarbon degradation, and the phylogenetic diversity of the microbial community in oiled Arctic shoreline sediments. IF-30 intermediate fuel grade oil was applied to the shoreline which was then divided into four plots. One was left untreated and two were tilled. Four applications of fertilizer were applied over a two-month period. Phospholipid fatty acid (PLFA), gene probe and 16S microbial community analysis suggested that bioremediation stimulated the metabolic activity, increased microbial biomass and genetic potential for aromatic hydrocarbon degradation, and increased the population of hydrocarbon degradation of an oiled Arctic shoreline microbial community. The results of this study are in agreement with the results from stimulation of oil biodegradation in temperate marine environments. It was concluded that biodegradation and fertilizer addition are feasible treatment methods for oil spills in Arctic regions. 31 refs., 3 tabs., 3 figs

  7. Atmospheric methane emissions coupled to a CO2-sink at an Arctic shelf seep area offshore NW Svalbard: Introducing the "Seep-Fertilization Hypothesis"

    Science.gov (United States)

    Greinert, Jens; Pohlman, John; Silyakova, Anna; Mienert, Jürgen; Ruppel, Carolyn; Casso, Michael

    2015-04-01

    Documented warming of intermediate waters by ~1C over the past 30 years along the western Svalbard margin has been suggested as a driver of climate-change induced dissociation of marine methane hydrate. However, recent evidence suggests methane release has been occurring for thousands of years near the upper limit of methane hydrate stability zone and that seasonal changes in bottom water temperature may be more important than longer-term warming of intermediate waters. However, the existence of hydrates at the upper limit of the gas hydrate zone has been based on modeling results only and gas hydrates have not been sampled successfully. Yearly studies, undertaken during RV Helmer Hanssen cruises as part of CAGE have shown that no significant amount of methane reaches the upper water column and is being released towards the atmosphere from this ca. 400m deep sites. The same is true for a very active seep area at the shelf break in 240m water depth where detailed hydroacoustic studies show fluctuating fluxes between 71 and 114 T/yr in total. Here we focus on studies conducted with the USGS Gas Analysis System (USGS-GAS). Continuous surface water methane and carbon dioxide concentrations and associated data are used to calculate sea-air fluxes with this cavity ring-down spectrometer-based analytical system. Only the shallow seep site (~90 m water depth) had appreciable methane in surface waters. We conducted an exhaustive survey of this site, mapping the full extent of the surface methane plume. To provide three-dimensional constraints, we acquired 65 vertical dissolved methane profiles to delineate the vertical and horizontal extent of the subsurface methane plume. The USGS-GAS data show that methane beyond the 'normal' background fluxes of ~1 µmol m-2 d-1 is elevated at the intensively bubbling shallow seep site (max. 35 µmol m-2 d-1) and near the shallow coastal zone where the fluxes over a large area reach 25 µmol m-2 d-1. Comparing coastal and seep fluxes on

  8. Low viral predation pressure in cold hypersaline Arctic sediments and limits on lytic replication.

    Science.gov (United States)

    Colangelo-Lillis, Jesse; Wing, Boswell A; Whyte, Lyle G

    2016-04-01

    Viruses are ubiquitous drivers of microbial ecology and evolution and contribute to biogeochemical cycling. Attention to these attributes has been more substantial for marine viruses than viruses of other environments. Microscopy-based investigation of the viral communities from two cold, hypersaline Arctic springs was undertaken to explore the effects of these conditions on microbe-viral ecology. Sediments and water samples were collected along transects from each spring, from anoxic spring outlets through oxygenated downstream channels. Viral abundance, virus-microbe ratios and modelled virus-microbe contact rates were lower than comparable aqueous and sedimentary environments and most similar to deep subsurface sediments. No individual cell from either spring was visibly infected. Viruses in these springs appear to play a smaller role in controlling microbial populations through lytic activity than in marine water column or surface sedimentary environments. Relief from viral predation indicates the microbial communities are primarily controlled by nutrient limitation. The similarity of these springs to deep subsurface sediments suggests a biogeographic divide in viral replication strategy in marine sediments. PMID:26743115

  9. Late quaternary palaeo-oceanography and palaeo-climatology from sediment cores of the eastern Arctic Ocean

    International Nuclear Information System (INIS)

    Box cores recovered along a N-S transect in the Eurasian Basin allow the establishment of a time scale for the Late Quaternary history of the Arctic Ocean, based on stable oxygen isotope stratigraphy and AMS 14C dating of planktonic foraminifers (N. pachyderma I.c.). This high resolution stratigraphy, in combination with sedimentological investigations (e.g. coarse fraction analysis, carbonate content, productivity of foraminifers), was carried out to reconstruct the glacial and inter-glacial Arctic Ocean palaeo-environment The sediment cores, which can be correlated throughout the sampling area in the Eastern Arctic Ocean, were dated as representing oxygen isotope stages 1 to 4/5. The sedimentation rates varied between a few mm/ka in glacials and approximately one cm/ka during the Holocene. The sediments allow a detailed sedimentological description of the depositional regime and the palaeo-oceanography of the Eastern Arctic Ocean. Changing ratios of biogenic and lithogenic components in the sediments reflect variations in the oceanographic circulation pattern in the Eurasian Basin during the Late Quaternary. Carbonate content (1-9wt.%), productivity of foraminifers (high in interglacial, low in glacial stages) and the terrigenous components are in good correlation with glacial and inter-glacial climatic fluctuations

  10. Radioactive cesium, cobalt and plutonium in biota, algae and sediments in the nonrestricted areas of the Russian Arctic Seas

    International Nuclear Information System (INIS)

    Biota, macroalgae and sediment samples were collected during scientific expeditions organized by the Murmansk Marine Biological Institute (MMBI) during 1993 - 1996 in the Barents, Petshora, Kara, Laptev and White seas and in the Kola Bay. The purpose of the expeditions was to study the levels of radioactive pollution in the Russian arctic seas

  11. The impacts of thermokarst on sediment, organic matter, and macroinvertebrate community dynamics in arctic headwater streams

    Science.gov (United States)

    Flinn, M.; Kampman, J.; Larouche, J. R.; Bowden, W. B.

    2010-12-01

    Recent research has documented changes in arctic climate that influence permafrost degradation and the incidence of thermokarst formation. In 2009 and 2010, we examined several thermokarst failures on headwater streams near Toolik Lake, AK, and the Kelly River area of the Noatak National Preserve, AK, USA. We quantified significant differences between reference (upstream) and impacted stream reaches affected by these thermokarst features. Sediment deposition at Toolik in 2009, measured with sediment traps, showed no differences in the organic fractions; however, the inorganic fraction was ~2x higher (PChironomidae) abundance and biomass doubled in the impacted reaches by late summer, mostly due to Dicrotopus, Psudokiefferiella, and Rheotanytarsus. Nemoura (Plecoptera, Nemouridae), a shredding stonefly, abundance and biomass were over 5x higher in the impacted reaches (PChironomidae) showed a 3-fold decrease in the impacted reaches (P<0.05). Results from several years of research indicate that thermokarst failures result in impacts that respond on different temporal scales. High sediment loading during initiation results in negative impacts on primary production and ecosystem function; however, the duration of these effects on primary consumers may diminish relatively quickly downstream and over time. Further research on these failures will help us to determine the trajectory of recovery.

  12. Early life history of daubed shanny (Teleostei: Leptoclinus maculatus) in Svalbard waters

    OpenAIRE

    Ottesen, Camilla; Hop, Haakon; Christiansen, Jørgen Schou; Falk-Petersen, Stig

    2011-01-01

    The daubed shanny (Leptoclinus maculatus, Family Stichaeidae) is considered to be an ecologically significant species in the arctic waters of Norway because of high abundance and the unique energy storage abilities of its postlarvae. Both postlarvae and adults are found in relative large abundances in Svalbard fjords as well as along the ice edge of north-east Svalbard, even at sub-zero temperatures. The postlarva feeds primarily on Calanus spp. and stores lipids from this high-energy diet in...

  13. Permafrost in Svalbard: a review of research history, climatic background and engineering challenges

    OpenAIRE

    Humlum, Ole; Instanes, Arne; Sollid, Johan Ludvig

    2003-01-01

    This paper reviews permafrost in High Arctic Svalbard, including past and current research, climatic background, how permafrost is affected by climatic change, typical permafrost landforms and how changes in Svalbard permafrost may impact natural and human systems. Information on active layer dynamics, permafrost and ground ice characteristics and selected periglacial features is summarized from the recent literature and from unpublished data by the authors. Permafrost thickness ranges from l...

  14. Monitoring cultural heritage environments in Svalbard – Smeerenburg, a whaling station on Amsterdam Island

    OpenAIRE

    Thuestad, Alma Elizabeth; Tømmervik, Hans; Solbø, Stian; Barlindhaug, Stine; Flyen, Anne Cathrine; Myrvoll, Elin Rose; Johansen, Bernt

    2015-01-01

    Cultural environments are not static and unchanging, they are subject to a number of site transfor-mation processes. Environmental hazards and human activity are among the primary degradation parameters for cultural heritage in Svalbard. The objective of this contribution is to demonstrate the potential advantages of utilising remote sensing for mapping and monitoring cultural heritage in a high arctic environment such as Svalbard. Our data illustrate how various factors associated to an unde...

  15. Distribution and sources of polycyclic aromatic hydrocarbons in surface sediments from the Bering Sea and western Arctic Ocean.

    Science.gov (United States)

    Zhao, Mengwei; Wang, Weiguo; Liu, Yanguang; Dong, Linsen; Jiao, Liping; Hu, Limin; Fan, Dejiang

    2016-03-15

    To analyze the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) and evaluate their potential ecological risks, the concentrations of 16 PAHs were measured in 43 surface sediment samples from the Bering Sea and western Arctic Ocean. Total PAH (tPAH) concentrations ranged from 36.95 to 150.21 ng/g (dry weight). In descending order, the surface sediment tPAH concentrations were as follows: Canada Basin>northern Chukchi Sea>Chukchi Basin>southern Chukchi Sea>Aleutian Basin>Makarov Basin>Bering Sea shelf. The Bering Sea and western Arctic Ocean mainly received PAHs of pyrogenic origin due to pollution caused by the incomplete combustion of fossil fuels. The concentrations of PAHs in the sediments of the study areas did not exceed effects range low (ERL) values. PMID:26806662

  16. Temperature induced decoupling of enzymatic hydrolysis and carbon remineralization in long-term incubations of Arctic and temperate sediments

    DEFF Research Database (Denmark)

    Robador, Alberto; Brüchert, Volker; Steen, Andrew;

    2010-01-01

    , and 20 ºC. The short-term temperature response of the active microbial community was tested in temperature gradient block incubations. The temperature optimum of extracellular enzymatic hydrolysis, as measured with a polysaccharide (chondroitin sulfate), differed between Arctic and temperate habitats......Extracellular enzymatic hydrolysis of high-molecular weight organic matter is the initial step in sedimentary organic carbon degradation and is often regarded as the rate-limiting step. Temperature effects on enzyme activities may therefore exert an indirect control on carbon mineralization. We...... by about 8–13 C in fresh sediments and in sediments incubated for 24 months. In both Arctic and temperate sediments, the temperature response of chondroitin sulfate hydrolysis was initially similar to that of sulfate reduction. After 24 months, however, hydrolysis outpaced sulfate reduction rates, as...

  17. Svalbard Project objectives and overview

    International Nuclear Information System (INIS)

    The primary objectives of this internationally funded experimental oil spill, carried out at Svalbard, Norway, during the summers of 1997 and 1998 are described and a project overview is provided. The objectives were to quantify the effectiveness of in-situ shoreline treatment options which are used to accelerate the natural processes that remove oil stranded on mixed coarse sediment beaches, and to investigate processes by which stranded oil is removed naturally. Selection of sediment relocation, mixing, bioremediation and natural removal were some of the options investigated. A total of 5,500 litres of IF-30 oil was applied to the upper beach face at three experimental sites. Two of the sites were used to assess the treatment technique of sediment relocation. The third site was used to study bioremediation, mixing and mixing combined with bioremediation. Each oiled/treated plot was compared to an oiled/untreated plot. Monitoring was conducted over a 400-day period. Data related to oil penetration, oil loading, oil movement to the sub -tidal environment, biodegradation, and toxicity were quantified

  18. Biogeographic patterns of bacterial microdiversity in Arctic deep-sea sediments (Hausgarten, Fram Strait

    Directory of Open Access Journals (Sweden)

    Pier Luigi eButtigieg

    2015-01-01

    Full Text Available Marine bacteria colonising deep-sea sediments beneath the Arctic ocean, a rapidly changing ecosystem, have been shown to exhibit significant biogeographic patterns along transects spanning tens of kilometres and across water depths reaching several thousands of metres (Jacob et al., 2013. Jacob et al. adopted what has become a classical view of microbial diversity based on operational taxonomic units clustered at the 97% sequence identity level of the 16S rRNA gene and observed a very large microbial community replacement at the Hausgarten Long-Term Ecological Research station (Eastern Fram Strait. Here, we revisited these data using the oligotyping approach with the aims of obtaining new insights into ecological and biogeographic patterns associated with bacterial microdiversity in marine sediments and of assessing the level of concordance of these insights with previously obtained results. Variation in oligotype dispersal range, relative abundance, co-occurrence, and taxonomic identity were related to environmental parameters such as water depth, biomass, and sedimentary pigment concentration. This study assesses ecological implications of the new microdiversity-based technique using a well-characterised dataset of high relevance for global change biology.

  19. Diversity of active aerobic methanotrophs along depth profiles of arctic and subarctic lake water column and sediments

    Science.gov (United States)

    He, Ruo; Wooller, Matthew J.; Pohlman, John W.; Quensen, John; Tiedje, James M.; Leigh, Mary Beth

    2012-01-01

    Methane (CH4) emitted from high-latitude lakes accounts for 2–6% of the global atmospheric CH4 budget. Methanotrophs in lake sediments and water columns mitigate the amount of CH4 that enters the atmosphere, yet their identity and activity in arctic and subarctic lakes are poorly understood. We used stable isotope probing (SIP), quantitative PCR (Q-PCR), pyrosequencing and enrichment cultures to determine the identity and diversity of active aerobic methanotrophs in the water columns and sediments (0–25 cm) from an arctic tundra lake (Lake Qalluuraq) on the north slope of Alaska and a subarctic taiga lake (Lake Killarney) in Alaska's interior. The water column CH4 oxidation potential for these shallow (~2m deep) lakes was greatest in hypoxic bottom water from the subarctic lake. The type II methanotroph, Methylocystis, was prevalent in enrichment cultures of planktonic methanotrophs from the water columns. In the sediments, type I methanotrophs (Methylobacter, Methylosoma and Methylomonas) at the sediment-water interface (0–1 cm) were most active in assimilating CH4, whereas the type I methanotroph Methylobacter and/or type II methanotroph Methylocystis contributed substantially to carbon acquisition in the deeper (15–20 cm) sediments. In addition to methanotrophs, an unexpectedly high abundance of methylotrophs also actively utilized CH4-derived carbon. This study provides new insight into the identity and activity of methanotrophs in the sediments and water from high-latitude lakes.

  20. Monitoring of greenhouse gases and aerosols at Svalbard and Birkenes

    Energy Technology Data Exchange (ETDEWEB)

    Myhre, C.L.; Hermansen, O.; Fjaeraa, A.M.; Lunder, C.; Fiebig, M.; Schmidbauer, N.; Krognes, T.; Stebel, K.

    2012-07-01

    The report summaries the activities and results of the greenhouse gas monitoring at the Zeppelin and observatory situated on Svalbard in Arctic Norway during the period 2001-2010 and the greenhouse gas monitoring and aerosol observations from Birkenes for 2010. The monitoring programme is performed by the NILU - Norwegian Institute for Air Research and funded by the Norwegian Pollution Control Authority (SFT) (now Climate and Pollution Agency) and NILU - Norwegian Institute for Air Research.(Author)

  1. Diversity of active aerobic methanotrophs along depth profiles of arctic and subarctic lake water column and sediments

    OpenAIRE

    He, Ruo; Wooller, Matthew J; Pohlman, John W.; Quensen, John; Tiedje, James M.; Leigh, Mary Beth

    2012-01-01

    Methane (CH4) emitted from high-latitude lakes accounts for 2–6% of the global atmospheric CH4 budget. Methanotrophs in lake sediments and water columns mitigate the amount of CH4 that enters the atmosphere, yet their identity and activity in arctic and subarctic lakes are poorly understood. We used stable isotope probing (SIP), quantitative PCR (Q-PCR), pyrosequencing and enrichment cultures to determine the identity and diversity of active aerobic methanotrophs in the water columns and sedi...

  2. Effect of recent climate change on Arctic Pb pollution: A comparative study of historical records in lake and peat sediments

    International Nuclear Information System (INIS)

    Historical changes of anthropogenic Pb pollution were reconstructed based on Pb concentrations and isotope ratios in lake and peat sediment profiles from Ny-Ålesund of Arctic. The calculated excess Pb isotope ratios showed that Pb pollution largely came from west Europe and Russia. The peat profile clearly reflected the historical changes of atmospheric deposition of anthropogenic Pb into Ny-Ålesund, and the result showed that anthropogenic Pb peaked at 1960s–1970s, and thereafter a significant recovery was observed by a rapid increase of 206Pb/207Pb ratios and a remarkable decrease in anthropogenic Pb contents. In contrast to the peat record, the longer lake record showed relatively high anthropogenic Pb contents and a persistent decrease of 206Pb/207Pb ratios within the uppermost samples, suggesting that climate-sensitive processes such as catchment erosion and meltwater runoff might have influenced the recent change of Pb pollution record in the High Arctic lake sediments. - Highlights: ► Historical changes of anthropogenic Pb pollution in Ny-Ålesund were reconstructed. ► Anthropogenic Pb in Ny-Ålesund was largely originated from W. European and Russia. ► Anthropogenic Pb recorded in peat sediments peaked at 1960–1970s and then declined. ► High anthropogenic fluxes were found in recent change of Pb record from lake sediments. ► Climate-sensitive processes might have influenced recent Pb accumulation rate in lakes. - This manuscript reports the effects of climate-sensitive processes on historical records of Pb pollution in sediments of Arctic lakes.

  3. Viable Species of Flamella (Amoebozoa: Variosea) Isolated from Ancient Arctic Permafrost Sediments.

    Science.gov (United States)

    Shmakova, Lyubov; Bondarenko, Natalya; Smirnov, Alexey

    2016-02-01

    Six viable strains of amoebae belonging to the genus Flamella (Amoebozoa, Variosea) were isolated from permafrost sediments sampled in the Russian Arctic region. Two of them are from late Pleistocene permafrost in North-East Siberia, and four--from Holocene and late Pleistocene in North-West Siberia. Light- and electron-microscopic study and molecular phylogeny show that these isolates represent two new species belonging to the genus Flamella. Both species are cyst-forming. This is a remarkable case of high resistance of protozoan cysts, allowing them to survive and recover an amoebae population after a very long, geologically significant period of rest; a "snapshot" of evolution in time. This study directly shows for the first time that amoeba cysts can be conserved not only for years and decades but for many thousand years and then recover, contributing to the formation of an active microbial community. We propose to name the new species as Flamella pleistocenica n.sp. and Flamella beringiania n.sp. Phylogenetic analysis shows that the genus Flamella is a robust and potentially species-rich group of Variosea. PMID:26735346

  4. EISCAT Svalbard radar

    Science.gov (United States)

    Lehtinen, Markku; Kangas, Jorma

    1992-02-01

    The main fields of interest of the Finnish scientists in EISCAT research are listed. Finnish interests in the Polar Cap Radar (PMR) and areas where the Finnish contribution could be important are addressed: radar techniques; sporadic E layers in the polar cap; atmospheric models; auroral studies in the polar cap; nonthermal plasmas in the F region; coordinated measurements with the Cluster satellites; studies of the ionospheric traveling; convection vortices; polar cap absorption; studies of lower atmosphere; educational program. A report on the design specification of an ionospheric and atmospheric radar facility based on the archipelago of Svalbard (Norway) is summarized.

  5. Ocean temperature oscillations enable reappearance of blue mussels Mytilus edulis in Svalbard after a 1000 year absence

    OpenAIRE

    Berge, Jørgen; Johnsen, Geir; Nilsen, Frank; Gulliksen, Bjørn; Slagstad, Dag

    2005-01-01

    We report the first observations of settled blue mussels Mytilus edulis L. in the high Arctic archipelago of Svalbard for the first time since the Viking Age. A scattered population was discovered at a single site at the mouth of Isfjorden in August 2004. Our data indicate that most mussels settled there as spat in 2002, and that larvae were transported by the West Spitsbergen Current northwards from the Norwegian coast to Svalbard the same year. This extension of the blue mussels’ distributi...

  6. Formate, acetate, and propionate as substrates for sulfate reduction in sub-arctic sediments of Southwest Greenland

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Jaussi, Marion; Røy, Hans;

    2015-01-01

    Volatile fatty acids (VFAs) are key intermediates in the anaerobic mineralization of organic matter in marine sediments. We studied the role of VFAs in the carbon and energy turnover in the sulfate reduction zone of sediments from the sub-arctic Godthåbsfjord (SW Greenland) and the adjacent...... turnover times increased from several hours at the sediment surface to several years at the bottom of the sulfate reduction zone. Thus, diffusion was not limiting the VFA turnover. Despite constant VFA concentrations, the Gibbs energies (ΔGr) of VFA-dependent sulfate reduction decreased downcore, from −28...... energetic limit at ~ −30 kJ (mol acetate)−1. It is not clear what controls VFA concentrations in the porewater but cell physiological constraints such as energetic costs of VFA activation or uptake could be important. We suggest that such constraints control the substrate turnover and result in a minimum...

  7. The geomorphological effect of cornice fall avalanches in the Longyeardalen valley, Svalbard

    Science.gov (United States)

    Eckerstorfer, M.; Christiansen, H. H.; Rubensdotter, L.; Vogel, S.

    2013-09-01

    The study of snow avalanches and their geomorphological effect in the periglacial parts of the cryosphere is important for enhanced geomorphological process understanding as well as hazard-related studies. Only a few field studies, and particularly few in the High Arctic, have quantified avalanche sedimentation. Snow avalanches are traditionally ranked behind rockfall in terms of their significance for mass-wasting processes of rockslopes. Cornice fall avalanches are at present the most dominant snow avalanche type at two slope systems, called Nybyen and Larsbreen, in the valley Longyeardalen in central Svalbard. Both slope systems are on northwest-facing lee slopes underneath a large summit plateau, with annual cornices forming on the top. High-frequency and magnitude cornice fall avalanching is observed by daily automatic time-lapse photography. In addition, rock debris sedimentation by cornice fall avalanches was measured directly in permanent sediment traps or by snow inventories. The results from a maximum of seven years of measurements in a total of 13 catchments show maximum mean rock debris sedimentation rates ranging from 8.2 to 38.7 kg m-2 at Nybyen, and from 0.8 to 55.4 kg m-2 at Larsbreen. Correspondingly, avalanche fan surfaces accreted from 2.6 to 8.8 mm yr-1 at Nybyen, and from 0.2 to 13.9 mm yr-1 at Larsbreen. This comparably efficient rockslope mass wasting is due to collapsing cornices producing cornice fall avalanches containing large amounts of rock debris throughout the entire winter. The rock debris of different origin stems from the plateau crests, the adjacent free rock face and the transport pathway, accumulating distinct avalanche fans at both slope systems. Cornice fall avalanche sedimentation also contributed to the development of a rock glacier at the Larsbreen site during the Holocene. We have recorded present maximum rockwall retreat rates of 0.9 mm yr-1 at Nybyen, but as much as 6.7 mm yr-1 at Larsbreen, while average Holocene

  8. Cloudiness and weather variation in central Svalbard in July 2013 as related to atmospheric circulation

    Czech Academy of Sciences Publication Activity Database

    Láska, K.; Chládová, Zuzana; Ambrožová, K.; Husák, J.

    2013-01-01

    Roč. 3, č. 2 (2013), s. 184-195. ISSN 1805-0689 Institutional support: RVO:68378289 Keywords : atmospheric circulation * climate * cloudiness * weather * Svalbard * Arctic Subject RIV: DO - Wilderness Conservation http://www.sci.muni.cz/CPR/6cislo/Laska.pdf

  9. Accelerated delivery of polychlorinated biphenyls (PCBs) in recent sediments near a large seabird colony in Arctic Canada

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) were measured in sediment cores from ponds located near a large seabird colony at Cape Vera, Devon Island, Arctic Canada. Surface sediment PCB concentrations were ∼5x greater in seabird-affected sites relative to a nearby control pond and were correlated with independent indicators of seabird activity including, sedimentary δ15N and lakewater chlorophyll a and cadmium concentrations. PCB fluxes were amongst the highest recorded from the High Arctic, ranging from 290 to 2400 ng m-2 yr-1. Despite a widespread ban of PCBs in the mid-1970s, PCB accumulation rates in our cores increased, with the highest values recorded in the most recent sediments. Possible mechanisms for the recent PCB increases include a vertical flux step driven by seabird-delivered nutrients and/or delayed loading of PCBs from the catchment into the ponds. The high PCB levels recorded in the seabird-affected sites suggest that seabird colonies are exposing coastal ecosystems to elevated levels of contaminants. - Seabird activity accelerates the delivery of PCBs from marine to terrestrial ecosystems.

  10. Accelerated delivery of polychlorinated biphenyls (PCBs) in recent sediments near a large seabird colony in Arctic Canada

    Energy Technology Data Exchange (ETDEWEB)

    Michelutti, Neal, E-mail: nm37@queensu.c [Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen' s University, 116 Barrie St., Kingston, ON K7L 3N6 (Canada); Liu, Huijun [Department of Environmental Science, Zhejiang Gongshang University, Hangzhou (China); Smol, John P. [Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen' s University, 116 Barrie St., Kingston, ON K7L 3N6 (Canada); Kimpe, Lynda E. [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5 (Canada); Keatley, Bronwyn E. [Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen' s University, 116 Barrie St., Kingston, ON K7L 3N6 (Canada); Mallory, Mark [Environment Canada, Iqaluit, NU (Canada); Macdonald, Robie W. [Department of Fisheries and Oceans, Sidney, BC V8L 4B2 (Canada); Douglas, Marianne S.V. [University of Alberta, Edmonton, AB T6G 2E3 (Canada); Blais, Jules M. [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5 (Canada)

    2009-10-15

    Polychlorinated biphenyls (PCBs) were measured in sediment cores from ponds located near a large seabird colony at Cape Vera, Devon Island, Arctic Canada. Surface sediment PCB concentrations were approx5x greater in seabird-affected sites relative to a nearby control pond and were correlated with independent indicators of seabird activity including, sedimentary delta{sup 15}N and lakewater chlorophyll a and cadmium concentrations. PCB fluxes were amongst the highest recorded from the High Arctic, ranging from 290 to 2400 ng m{sup -2} yr{sup -1}. Despite a widespread ban of PCBs in the mid-1970s, PCB accumulation rates in our cores increased, with the highest values recorded in the most recent sediments. Possible mechanisms for the recent PCB increases include a vertical flux step driven by seabird-delivered nutrients and/or delayed loading of PCBs from the catchment into the ponds. The high PCB levels recorded in the seabird-affected sites suggest that seabird colonies are exposing coastal ecosystems to elevated levels of contaminants. - Seabird activity accelerates the delivery of PCBs from marine to terrestrial ecosystems.

  11. New records of driftwood lichens in the Kaffiøyra Plain (NW Spitsbergen, Svalbard

    Directory of Open Access Journals (Sweden)

    Węgrzyn Michał

    2015-06-01

    Full Text Available This paper refers to lichen biota growing on driftwood in the Kaffiøyra Plain (NW Spitsbergen, Svalbard. The presented list of 25 lichenized fungi includes both the eurytopic, accidental, typical, and stenotopic species. Taxa that belong to the last two groups can be considered as lignicolous. This study confirms the existence of a specific group of lichen species, for which the driftwood is a main substrate in the Arctic. Additionally, five lichen species new for the whole Svalbard were recorded, namely: Candelariella coralliza, Elixia flexella, Lecanora saligna, Lecidea plebeja, and Xylographa sibirica.

  12. Natural self cleaning and enhanced self cleaning of crude oil, crude oil emulsions and diesel from Arctic shoreline sediments

    International Nuclear Information System (INIS)

    Natural removal and enhanced removal by chemical treatment of crude oil, crude oil emulsion, and diesel were studied in field and basin experiments on Spitsbergen. The beach types comprised gravel beaches, sandy beaches, and mud flats. Each shoreline was divided into nine 25-m2 plots. The chemical treatment comprised Corexit 7664 and Finasol OSR12. Oil concentrations were monitored from the time of contamination and until the end of the season. The upper and lower zones of the beach were treated separately. The decrease in oil concentration during an Arctic summer season was found to be considerable in all the experiments except in the mud flat sediments. Partitioning in the sediment depends on the water level in the sediment, thus oil retention is limited in the more or less water-saturated lower beach zone. Although the overall effect of chemical treatment can be questioned, the chemicals have an effect on oil removal from the sediment. The extensive removal of oil from the control plots indicates that a leave-alone option can be viable on these types of beaches unless extreme requirements for immediate cleanliness exist. 4 refs., 10 figs., 2 tabs

  13. Distributed energy and surface mass balance modeling of Austfonna, Svalbard.

    OpenAIRE

    2010-01-01

    The climatic influence on a large cold/polythermal Arctic ice cap with substantial surface melt was investigated by calculating the surface energy balance (SEB)and subsurface properties. This method was applied on Austfonna (∼8100km2,NE Svalbard) during melt season 2004. Surface mass balance was calculated from April 23rd to September 26th on the grid of a 1000m resolution digital elevation model(DEM). Hourly in-situ meteorological measurements by an automatic weather station(AWS) located on ...

  14. Modelling of surface wind in petuniabukta (Billefjorden, Svalbard)

    Czech Academy of Sciences Publication Activity Database

    Chládová, Zuzana; Láska, K.; Hošek, Jiří

    České Budějovice: Faculty of Science, University of South Bohemia in České Budějovice, 2014. s. 36-37. ISBN 978-80-7394-463-6. [Polar Ecology Conference 2014. 21.09.2014–21.09.2014, České Budějovice] Institutional support: RVO:68378289 Keywords : wind * atmospheric circulation * wrf model * wasp model * Svalbard * Arctic Subject RIV: DO - Wilderness Conservation http://polar.prf.jcu.cz/data/PEC2014_abstract_book_final.pdf

  15. Fluxes of dissolved methane from the seafloor at the landward limit of the gas hydrate stability zone offshore western Svalbard

    Science.gov (United States)

    Graves, Carolyn; Steinle, Lea; Niemann, Helge; Rehder, Gregor; Fisher, Rebecca; Lowry, Dave; Connelly, Doug; James, Rachael

    2015-04-01

    Seepage of methane from seafloor sediments offshore Svalbard may partly be driven by destabilization of gas hydrates as a result of bottom water warming. As the world's oceans are expected to continue to warm, in particular in the Arctic, destabilization of hydrate may become an important source of methane to ocean bottom waters and potentially to the overlying atmosphere where it contributes to further warming. In order to quantify the fate of methane from seafloor seeps, we have determined the distribution of dissolved methane in the water column on the upper slope and shelf offshore western Svalbard during three research cruises with RRS James Clark Ross (JR253) in 2011 and R/V Maria S. Merian (MSM21/4) and Heincke (HE387) in 2012. Combining discrete depth profile methane concentration data and surface seawater concentrations from an equilibrator-online system with oxidation rate measurements and atmospheric methane observations allows insight into the fate of methane input from the seafloor, and evaluation of the potential contributions of other methane sources. A simple box model considering oxidation and horizontal and vertical mixing indicates that the majority of seep methane is oxidized at depth. A plume of high methane concentrations is expected to persist more than 100 km downstream of the seepage area in the rapid barotropic West Spitsbergen Current, which flows northward towards the Arctic Ocean. We calculate that the diffusive sea-air flux of methane is largest on the shallow shelf, reaching 36 μmol m-2 day-1. Over the entire western Svalbard region there is a persistent, but small, source of methane from surface seawater to the overlying atmosphere. Measurements of the atmospheric methane carbon isotope signature indicate that the seafloor seeps do not make a significant contribution to atmospheric methane in this region, which is consistent with earlier studies. Observations downstream of the seepage region are necessary to further constrain

  16. Relatively high antibiotic resistance among heterotrophic bacteria from arctic fjord sediments than water - Evidence towards better selection pressure in the fjord sediments

    Science.gov (United States)

    Hatha, A. A. Mohamed; Neethu, C. S.; Nikhil, S. M.; Rahiman, K. M. Mujeeb; Krishnan, K. P.; Saramma, A. V.

    2015-12-01

    The objective of this study was to determine the prevalence of antibiotic resistance among aerobic heterotrophic bacteria and coliform bacteria from water and sediment of Kongsfjord. The study was based on the assumption that arctic fjord environments are relatively pristine and offer very little selection pressure for drug resistant mutants. In order to test the hypothesis, 200 isolates belonging to aerobic heterotrophic bacteria and 114 isolates belonging to coliforms were tested against 15 antibiotics belonging to 5 different classes such as beta lactams, aminoglycosides, quinolones, sulpha drugs and tetracyclines. Resistance to beta lactam and extended spectrum beta lactam (ESBL) antibiotics was considerably high and they found to vary significantly (p antibiotic resistance against ESBL's extent and diversity of antibiotic resistance (as revealed by multiple antibiotic resistance index and resistance patterns), was high in the aerobic heterotrophic bacteria. Most striking observation was that isolates from fjord sediments (both heterotrophic bacteria and coliforms) in general showed relatively high prevalence of antibiotic resistance against most of the antibiotics tested, indicating to better selection pressure for drug resistance mutants in the fjord sediments.

  17. Historical trends in persistent organic pollutants and metals recorded in sediment from Lake Ellasjoen, Bjornoya, Norwegian Arctic

    International Nuclear Information System (INIS)

    Ellasjoen receives contaminants from both atmospheric and biological transport (seabird guano). Historical trends of selected persistent organic pollutants and metals were determined by interpretation of down-core contaminant profiles in conjunction with sediment layer ages, determined by the 210Pb method. Polychlorinated biphenyls (PCBs) and dichloro-diphenyl-trichloroethane and metabolites (DDTs) increased from about 1930 until 1970 (max. sum PCBs 71.8 ng/g dry weight (dw), max sum DDTs 4.0 ng/g dw), declining afterwards to 46.4 ng/g dw and 1.6 ng/g dw, respectively. Polybrominated diphenylethers (PBDEs) concentrations are increasing in Ellasjoen, reaching 0.73 ng/g dw in 2001. Hexabromocyclododekane (HBCD) was measured only in sediment from 1-2 cm depth (0.43 and 3.88 ng/g dw of α- and γ-HBCD, respectively). Most metals (As, Cd, Co, Ni and Zn) showed a similar pattern as PCBs. No clear trends were observed for Cr, Pb or V. Mercury (Hg) has increased gradually since the beginning of the industrial era. - Levels of Polybrominated diphenyl ethers are increasing in sediment from a Norwegian, Arctic lake

  18. First evidence of the Ellesmerian metamorphism on Svalbard

    Science.gov (United States)

    Kośmińska, Karolina; Majka, Jarosław; Manecki, Maciej; Schneider, David A.

    2016-04-01

    The Ellesmerian fold-and-thrust belt is exposed in the High Arctic from Ellesmere Island in the east, through North Greenland, to Svalbard in the west (e.g. Piepjohn et al., 2015). It developed during Late Devonian - Early Carboniferous, and overprinted older (mainly Caledonian) structures. It is thought that this fold-and-thrust belt was formed due to collision of the Pearya Terrane and Svalbard with the Franklinian Basin of Laurentia. Traditionally, the Ellesmerian fold-and-thrust belt comprises a passive continental margin affected by foreland deformation processes, but the exact larger scale tectonic context of this belt is disputable. It is partly because the Eocene Eurekan deformation superimposed significantly the Ellesmerian structures, thus making the reconstruction of the pre-Eurekan history very difficult. Here we present for the first time evidence for Ellesmerian metamorphism within the crystalline basement of Svalbard. These rocks are exposed in the Pinkie unit on Prins Karls Forland (W-Svalbard), which exhibits tectonic contacts with the overlying sequences. The Pinkie unit is mainly composed of strongly deformed lithologies such as laminated quartzites, siliciclastic rocks and garnet-bearing mica schists. Detrital zircon dating yielded ages as young as Neoproterozoic (0.95-1.05 Ga), thus the Pinkie unit is considered to be Neoproterozoic (Kośmińska et al., 2015a). The M1 assemblages and D1 structures are affected by D2 mylonitization (cf. Faehnrich et al., 2016, this meeting). Petrological characterization and Th-U-total Pb chemical monazite dating have been performed on the Pinkie metapelites. These rocks exhibit an apparent inverted Barrovian metamorphic sequence, within which three metamorphic zones have been distinguished: garnet+staurolite+muscovite+biotite, garnet+staurolite+kyanite+muscovite+biotite, garnet+kyanite+muscovite+biotite. The P-T estimates using the QuiG barometry coupled with thermodynamic modelling revealed that the

  19. Flocculation alters the distribution and flux of melt-water supplied sediments and nutrients in the Arctic

    DEFF Research Database (Denmark)

    Markussen, Thor Nygaard; Andersen, Thorbjørn Joest; Ernstsen, Verner Brandbyge;

    settling tubes were sampled to enable sub-sampling of different floc size fractions. Flocculation was observed during periods with low turbulent shear and also at the front of the fresh water plume resulting in significant volumes of large sized flocs at depth below the plume. The floc sizes and volumes...... environment but comparatively little is known about the flocculation processes in the Arctic. We investigated flocculation dynamics from a melt-water river in the inner Disko Fjord, West Greenland. A novel, laser-illuminated camera system significantly improved the particle size measurement capabilities and...... were correlated with particulate and dissolved C, Fe and N concentrations. The observed flocculation dynamics highlight the potential for redistributing sediments and nutrients in the water column, which is important for understanding these environments and ecosystems in the past and future....

  20. Characters of the organic δ13C and its climatic information in sediment cores of the lakes nearby the arctic yellow river station of China

    International Nuclear Information System (INIS)

    Arctic is favored by researchers due to its sensitivity and feedback to Global Climate Change, and the organic δ13C record of lake sediment is a key indicator for the environ- mental climate change. The sedimentary rates and δ13C of two sediment cores (No.1 and No.2), collected from two lakes near the Arctic Yellow River Station of China during July to Aug of 2007, were determined in order to investigate the climate change of the Arctic during the past centuries. The sedimentary rates, determined with 210Pb method, of sample No.1 and sample No.2 were 1.05 mm/a and 0.91 mm/a, respectively, and the vertical distribution of organic δ13C of two sediment cores have similar trends during the same period. The results show that the temperature at the Arctic Yellow River Station of China during the last three centuries was unsteady, and was alternating with a 'lower-higher-lower' process. (authors)

  1. The recognition of transient compressional fault slow-slip along the northern shore of Hornsund Fjord, SW Spitsbergen, Svalbard

    Czech Academy of Sciences Publication Activity Database

    Stemberk, Josef; Briestenský, Miloš; Cacon, S.

    2015-01-01

    Roč. 36, č. 2 (2015), s. 109-123. ISSN 0138-0338 R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985891 Keywords : Arctic * Svalbard * Hornsund * 3-D fault displacement monitoring * transient slow fault slip Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.275, year: 2014

  2. Distribution of molluscan remains in the sediment of the Chukchi Sea and its vicinity, the Arctic

    Institute of Scientific and Technical Information of China (English)

    Gao Aiguo; Xu Fengshan; Sun Haiqing; Li Lon

    2003-01-01

    The result of an analysis of mollusca remains collected from the Chukchi Sea, Beaufort Sea and Bering Sea in the First Chinese National Arctic Research Expedition, from July to September,1999 is presented. Seventeen species of mollusca have been identified, which belong to two classes: Bivalvia and Gastropoda. The compositions of the mollusca are very simple. According to the distribution pattern two groups may be distinguished among molluscan species. The Pan-Arctic and circumboreal group comprises Nuculana pernula, N. radiata, Nucula bellotii, Astarte montagui, Seripes groenlandicus, Macoma calcarea, M. moesta alaskana, Liocyma fluctuosa, Mya pseudoarenaria and Turritella polaris. Three species, Cyclocardia crebricos tata, Trichotrois coronata and Argobuccinum oregonense are components of the Pan-Arctic and Pacific boreal group. With regard to feeding habits, detritus feeders dominate. There are 7 species of detritus feeders, i.e. , Nuculana pernula, N. radiata,Nucula bellotii , Macoma calcarea , M. moesta alaskana , Macoma sp. and Trichotropis coronata . Detritus feeders are dominant with regard to the numbers of species as well as to the frequency of occurrence. Macoma calcarea is the most abundant species.

  3. The last interglacial-glacial period on spitsbergen, Svalbard

    Science.gov (United States)

    Mangerud, Jan; Svendsen, John Inge

    The glaciation history of Svalbard (78°N) and the NW Barents Sea is reconstructed for the last 130 ka, based on studies of sediments exposed in coastal cliffs at the head of Isfjorden. Four different till beds separated by marine sediments are recognized. The lowest marine formation, containing Mytilus edulis, reflects warmer conditions than at present, and is correlated with the last interglacial, the Eemian of Europe and Oxygen Isotope Substage 5e in the deep sea. The post-Eemian tills are inferred to represent major glaciations around 110 ka BP, 75-50 ka BP, and 25-10 ka BP. During the intervening intervals the glaciers on Svalbard were not significantly larger than at present and the NW Barents Sea was probably ice-free. The ice-free periods, named Phantomodden and Kapp Ekholm interstadials, lasted from about 110 to 75 and from 50 to 25 ka BP respectively. The marine fauna from both these interstadials indicate seasonally ice free conditions. The ages of the recorded glaciations coincide with, or are slightly younger than, periods with insolation minima, which at this latitude is determined by a low tilt of the Earth's axis. Thus we postulate that the Quaternary glaciations of Svalbard were driven by orbital variations with the 41 ka tilt period, in contrast to the lower-latitude glaciations of Scandinavia that were partly driven by the precession cycle with a periodicity of around 23 ka.

  4. Elevated levels of ingested plastic in a high Arctic seabird, the northern fulmar (Fulmarus glacialis)

    OpenAIRE

    Trevail, A.M.; Gabrielsen, G. W.; Kuhn, S.; Franeker, van, J.A.

    2015-01-01

    Plastic pollution is of worldwide concern; however, increases in international commercial activity in the Arctic are occurring without the knowledge of the existing threat posed to the local marine environment by plastic litter. Here, we quantify plastic ingestion by northern fulmars, Fulmarus glacialis, from Svalbard, at the gateway to future shipping routes in the high Arctic. Plastic ingestion by Svalbard fulmars does not follow the established decreasing trend away from human marine impac...

  5. Seasonality of vertical flux and sinking particle characteristics in an ice-free high arctic fjord-Different from subarctic fjords?

    Science.gov (United States)

    Wiedmann, Ingrid; Reigstad, Marit; Marquardt, Miriam; Vader, Anna; Gabrielsen, Tove M.

    2016-02-01

    The arctic Adventfjorden (78°N, 15°E, Svalbard) used to be seasonally ice-covered but has mostly been ice-free since 2007. We used this ice-free arctic fjord as a model area to investigate (1) how the vertical flux of biomass (chlorophyll a and particulate organic carbon, POC) follows the seasonality of suspended material, (2) how sinking particle characteristics change seasonally and affect the vertical flux, and (3) if the vertical flux in the ice-free arctic fjord with glacial runoff resembles the flux in subarctic ice-free fjords. During seven field investigations (December 2011-September 2012), suspended biomass was determined (5, 15, 25, and 60 m), and short-term sediment traps were deployed (20, 30, 40, and 60 m), partly modified with gel-filled jars to study the size and frequency distribution of sinking particles. During winter, resuspension from the seafloor resulted in large, detrital sinking particles. Intense sedimentation of fresh biomass occurred during the spring bloom. The highest POC flux was found during autumn (770-1530 mg POC m- 2 d- 1), associated with sediment-loaded glacial runoff and high pteropod abundances. The vertical biomass flux in the ice-free arctic Adventfjorden thus resembled that in subarctic fjords during winter and spring, but a higher POC sedimentation was observed during autumn.

  6. Fluid composition of the sediment-influenced Loki's Castle vent field at the ultra-slow spreading Arctic Mid-Ocean Ridge

    Science.gov (United States)

    Baumberger, Tamara; Früh-Green, Gretchen L.; Thorseth, Ingunn H.; Lilley, Marvin D.; Hamelin, Cédric; Bernasconi, Stefano M.; Okland, Ingeborg E.; Pedersen, Rolf B.

    2016-08-01

    The hydrothermal vent field Loki's Castle is located in the Mohns-Knipovich bend (73°N) of the ultraslow spreading Arctic Mid-Ocean Ridge (AMOR) close to the Bear Island sediment fan. The hydrothermal field is venting up to 320° C hot black smoker fluids near the summit of an axial volcanic ridge. Even though the active chimneys have grown on a basaltic ridge, geochemical fluid data show a strong sedimentary influence into the hydrothermal circulation at Loki's Castle. Compelling evidence for a sediment input is given by high alkalinity, high concentrations of NH4+, H2, CH4, C2+ hydrocarbons as well as low Mn and Fe contents. The low δ13C values of CO2 and CH4 and the thermogenic isotopic pattern of the C2+ hydrocarbons in the high-temperature vent fluids clearly point to thermal degradation of sedimentary organic matter and illustrate diminution of the natural carbon sequestration in sediments by hydrothermal circulation. Thus, carbon-release to the hydrosphere in Arctic regions is especially relevant in areas where the active Arctic Mid-Ocean Ridge system is in contact with the organic matter rich detrital sediment fans.

  7. Climate-related research in Svalbard

    International Nuclear Information System (INIS)

    The Svalbard archipelago is located in the Norwegian Arctic, 76-81N. In the Kongsfjord area, 79N, on northwest Spitsbergen, there has been increasing research activity in several climate-related disciplines over the last few years. This research will contribute to the global efforts on monitoring and detecting possible global changes. An intensified program monitoring hydrological processes was run from 1974 to 1978 and restarted in 1988. One well-equipped station for atmospheric research is also established. Four major glaciers are being thoroughly investigated, a program which includes mass balance studies, drainage patterns and core analyses. Since 1978 a permafrost station has been operated in Svea, south-central Spitsbergen. The trend in glacier mass balance analyses shows fairly stable negative conditions, the net balance is slightly increasing due to a slight increase in the winter precipitation. There is no sign of climatic warming through increased melting. The temperature data show a very slight cooling during the ablation period. A reconstruction of mass balance data for the Broegger glacier shows that the mass balance has been consistently negative since 1918

  8. Phylogenetic Diversity and Biological Activity of Actinobacteria Isolated from the Chukchi Shelf Marine Sediments in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Meng Yuan

    2014-03-01

    Full Text Available Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis.

  9. Phylogenetic diversity and biological activity of actinobacteria isolated from the Chukchi Shelf marine sediments in the Arctic Ocean.

    Science.gov (United States)

    Yuan, Meng; Yu, Yong; Li, Hui-Rong; Dong, Ning; Zhang, Xiao-Hua

    2014-03-01

    Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis. PMID:24663116

  10. Temperature response of denitrification and anaerobic ammonium oxidation rates and microbial community structure in Arctic fjord sediments.

    Science.gov (United States)

    Canion, Andy; Overholt, Will A; Kostka, Joel E; Huettel, Markus; Lavik, Gaute; Kuypers, Marcel M M

    2014-10-01

    The temperature dependency of denitrification and anaerobic ammonium oxidation (anammox) rates from Arctic fjord sediments was investigated in a temperature gradient block incubator for temperatures ranging from -1 to 40°C. Community structure in intact sediments and slurry incubations was determined using Illumina SSU rRNA gene sequencing. The optimal temperature (Topt ) for denitrification was 25-27°C, whereas anammox rates were optimal at 12-17°C. Both denitrification and anammox exhibited temperature responses consistent with a psychrophilic community, but anammox bacteria may be more specialized for psychrophilic activity. Long-term (1-2 months) warming experiments indicated that temperature increases of 5-10°C above in situ had little effect on the microbial community structure or the temperature response of denitrification and anammox. Increases of 25°C shifted denitrification temperature responses to mesophilic with concurrent community shifts, and anammox activity was eliminated above 25°C. Additions of low molecular weight organic substrates (acetate and lactate) caused increases in denitrification rates, corroborating the hypothesis that the supply of organic substrates is a more dominant control of respiration rates than low temperature. These results suggest that climate-related changes in sinking particulate flux will likely alter rates of N removal more rapidly than warming. PMID:25115991

  11. Magnetostratigraphy of sediments from Lake El'gygytgyn ICDP Site 5011-1: paleomagnetic age constraints for the longest paleoclimate record from the continental Arctic

    Directory of Open Access Journals (Sweden)

    E. M. Haltia

    2013-09-01

    Full Text Available Paleomagnetic measurements were performed on sediments drilled from ICDP Site 5011-1 in Lake El'gygytgyn (67°30' N, 172°05' E located in Far East Russian Arctic. The lake fills partly a crater formed by a meteorite impact 3.58 ± 0.04 Ma ago. Sediments from three parallel cores (5011-1A, 5011-1B and 5011-1C, recovered from the middle part of the lake, yielded a total of 355 m of sediment. Sediments are characterized by variable lithology, where intervals of homogenous and laminated sediments alternate, and mass movement deposits of variable thickness occur frequently along the sediment profile. Mineral magnetic investigation made on sediments enclosed in core catchers suggests that magnetic carrier in these sediments is partly maghemitized Ti-rich pseudo-single domain magnetite. Its detrital origin could be shown by mineral magnetic measurements and SEM-EDS analyses performed on mini-sized cylindrical rock samples, polished rock sections, creek sediments and magnetic extracts prepared from them. The intensity of the natural remanent magnetization (NRM in the sediments is mainly high with a range from about 1 to 1000 mA m−1. Most of the sediments carry a stable magnetization component interpreted as primary depositional remanent magnetization. Characteristic inclination data show alternating intervals of steep positive and negative inclinations that were used to assign magnetic polarity to the lake sediment profile. This was a rather straightforward procedure owing to the mainly high quality of data. The Matuyama/Gauss (2.608 Ma and Brunhes/Matuyama (0.780 Ma reversals were recognized in the sediments. Furthermore, during the Gauss chron the Mammoth and Kaena reversed subchrons, and during the Matuyama, the Olduvai and Jaramillo normal subchrons, as well as the Réunion and Cobb Mountain cryptochrons were identified. Sediment deposition rate is highest at the base of the sequence laid down in the beginning of Gauss chron, when deposition rate

  12. Interaction between Cenozoic fault activity and sediment influx in the Arctic region: new thermochronologic data and seismic study

    Science.gov (United States)

    Bigot-Buschendorf, Maelianna; Mouthereau, Frédéric; Fillon, Charlotte; Loget, Nicolas; Labrousse, Loïc; Werner, Philippe; Bernet, Matthias; Ehlers, Todd

    2015-04-01

    The Alaskan Brooks Range and its canadian counterpart, the British Mountains result from the Meso-Cenozoic collision of the Arctic continental margin with accreted volcanic arcs and adjacent continental terranes. Because of its location and known potential for oil industries, more attention has been brought to this area for the last few years. While the timing of collisional events, duration, and rates of exhumation associated with mountain building is now better understood, the causes of these exhumation events are still largely unknown. Published constraints and our present data are consistent with progressive cooling from 105 to 25 Ma, with rates of exhumation constant across the range until 35-25 Ma. From 35 Ma onwards, exhumation likely slowed in concomitance with underplating/duplexing in the inner part of the belt (Doonerak window) and activation of the northernmost thrust. The earliest cooling stage (from 100 Ma) marking the onset of the Brookian orogeny is recorded by a low order coarsening upward sequence in the foreland. On the contrary, the latest stage of cooling (at 35 Ma) is not linked to the construction of the range but more likely due to a reorganization of the wedge possibly related to changes in the regional climatic or geodynamic boundary conditions. First, we aim at reconstructing the time-temperature evolution of the British Mountains by combining new (U-Th)/He and fission-tracks ages on zircon and apatite ; our first thermochronological data in the British Mountains show ages ranging from 110 to 25 Ma from range to basin. These data will permit to reconstruct the thermal history of the British Mountains and its basin, and to estimate the exhumation rates associated to the main unities. Then, we also examine the role of climate during the Tertiary period. Some markers indicate a climate change at this period which could be registered in the sedimentation. Therefore we determine the part of climate by analyzing seismic lines in the Beaufort

  13. Status and biology of ringed seals (Phoca hispida in Svalbard

    Directory of Open Access Journals (Sweden)

    Christian Lydersen

    2014-04-01

    for mothers was 21.2 min. In order to produce a weaned pup, the net energy expenditure for a ringed seal mother is 1,073 MJ. This energy value corresponds to the consumption of 185 kg of polar cod or 282 kg of P. libellula. The annual gross energy consumption for adult males and females is calculated to be 5,600 MJ and 7,300 MJ, respectively. The main predators of ringed seals in Svalbard are polar bears (Ursus maritimus and Arctic foxes (Alopex lagopus. In addition, both glaucous gulls (Larus hyperboreus and walruses (Odobenus rosmarus are documented as predators of ringed seals in this area. Heavy predation pressure is probably the main factor explaining why pups of this species start diving at such a young age, why they have access to so many breathing holes (8.7 on average and why they keep their white coat long after its thermoregulatory properties have vanished. Pollution levels in ringed seals from Svalbard are, generally speaking, similar to levels in other areas of the Arctic.

  14. Impacts of Ocean Acidification on Sediment Processes in Shallow Waters of the Arctic Ocean

    OpenAIRE

    Frédéric Gazeau; Pieter van Rijswijk; Lara Pozzato; Middelburg, Jack J.

    2014-01-01

    Despite the important roles of shallow-water sediments in global biogeochemical cycling, the effects of ocean acidification on sedimentary processes have received relatively little attention. As high-latitude cold waters can absorb more CO2 and usually have a lower buffering capacity than warmer waters, acidification rates in these areas are faster than those in sub-tropical regions. The present study investigates the effects of ocean acidification on sediment composition, processes and sedim...

  15. Calculations of in-snow NO2 and OH radical photochemical production and photolysis rates: A field and radiative-transfer study of the optical properties of Arctic (Ny-Ålesund, Svalbard) snow

    Science.gov (United States)

    France, J. L.; King, M. D.; Lee-Taylor, J.; Beine, H. J.; Ianniello, A.; Domine, F.; MacArthur, A.

    2011-12-01

    Depth-integrated production rates of OH radicals and NO2 molecules from snowpacks in Ny-Ålesund, Svalbard, are calculated from fieldwork investigating the light penetration depth (e-folding depth) and nadir reflectivity of snowpacks during the unusually warm spring of 2006. Light penetration depths of 8.1, 11.3, 5.1, and 8.2 cm were measured for fresh, old, marine-influenced, and glacial snowpacks, respectively (wavelength 400 nm). Radiative-transfer calculations of the light penetration depths with reflectivity measurements produced scattering cross sections of 5.3, 9.5, 20, and 25.5 m2 kg-1 and absorption cross sections of 7.7, 1.4, 3.4, and 0.5 cm2 kg-1 for the fresh, old, marine-influenced, and glacial snowpacks, respectively (wavelength 400 nm). Photolysis rate coefficients, J, are presented as a function of snow depth and solar zenith angle for the four snowpacks for the photolysis of H2O2 and NO3-. Depth-integrated production rates of hydroxyl radicals are 1270, 2130, 950, and 1850 nmol m-2 h-1 (solar zenith angle of 60°) for fresh, old, marine-influenced, and glacial snowpacks, respectively. Depth-integrated production rates of NO2 are 32, 56, 11, and 22 nmol m-2 h-1 (solar zenith angle of 60°) for the fresh, old, marine-influenced, and glacial snowpacks, respectively. The uncertainty of repeated light penetration depth measurement was determined to be ˜20%, which propagates into a 20% error in depth-integrated production rates. A very simple steady state hydroxyl radical calculation demonstrates that a pseudo first-order loss rate of OH radicals of ˜102-104 s-1 is required in snowpack. The snowpacks around Ny-Ålesund are thick enough to be considered optically infinite.

  16. Reproduction and winter biology of polar cod Boreogadus saida from Svalbard waters

    OpenAIRE

    Korshunova, Ekaterina

    2012-01-01

    Polar cod (Boreogadus saida) is considered to be a key species in the Arctic marine ecosystems. Yet detailed or even basic knowledge regarding its biology and adaptations, especially during the polar night, are in many cases poor. No field data is presently available on the gonad development of polar cod, its reproductive biology and associated bioenergetics. Accordingly, polar cod was sampled at different locations in Svalbard waters in August, September, November and January. Gonadosomatic ...

  17. An inter-laboratory investigation of the Arctic sea ice biomarker proxy IP25 in marine sediments: key outcomes and recommendations

    Science.gov (United States)

    Belt, S. T.; Brown, T. A.; Ampel, L.; Cabedo-Sanz, P.; Fahl, K.; Kocis, J. J.; Massé, G.; Navarro-Rodriguez, A.; Ruan, J.; Xu, Y.

    2014-01-01

    We describe the results of an inter-laboratory investigation into the identification and quantification of the Arctic sea ice biomarker proxy IP25 in marine sediments. Seven laboratories took part in the study, which consisted of the analysis of IP25 in a series of sediment samples from different regions of the Arctic, sub-Arctic and Antarctic, additional sediment extracts and purified standards. The results obtained allowed 4 key outcomes to be determined. First, IP25 was identified by all laboratories in sediments from the Canadian Arctic with inter-laboratory variation in IP25 concentration being substantially larger than within individual laboratories. This greater variation between laboratories was attributed to the difficulty in accurately determining instrumental response factors for IP25, even though laboratories were supplied with appropriate standards. Second, the identification of IP25 by 3 laboratories in sediment from SW Iceland that was believed to represent a blank, was interpreted as representing a better limit of detection or quantification for such laboratories, contamination or mis-identification. These alternatives could not be distinguished conclusively with the data available, although it is noted that the precision of these data was significantly poorer compared with the other IP25 concentration measurements. Third, 3 laboratories reported the occurrence of IP25 in a sediment sample from the Antarctic Peninsula even though this biomarker is believed to be absent from the Southern Ocean. This anomaly is attributed to a combined chromatographic and mass spectrometric interference that results from the presence of a di-unsaturated highly branched isoprenoid (HBI) pseudo-homologue of IP25 that occurs in Antarctic sediments. Finally, data are presented that suggest that extraction of IP25 is consistent between Accelerated Solvent Extraction (ASE) and sonication methods and that IP25 concentrations based on 7-hexylnonadecane as an internal standard

  18. Past Arctic aliens have passed away, current ones may stay

    OpenAIRE

    2015-01-01

    Increased human activity and climate change are expected to increase the numbers and impact of alien species in the Arctic, but knowledge of alien species is poor in most Arctic regions. Through field investigations over the last 10 years, and review of alien vascular plant records for the high Arctic Archipelago Svalbard over the past 130 years, we explored long term trends in persistence and phenology. In total, 448 observations of 105 taxa have been recorded from 28 sites. Recent surveys a...

  19. Quantitative and phylogenetic study of the Deep Sea Archaeal Group in sediments of the arctic mid-ocean spreading ridge

    Directory of Open Access Journals (Sweden)

    Steffen LethJørgensen

    2013-10-01

    Full Text Available In marine sediments archaea often constitute a considerable part of the microbial community, of which the Deep Sea Archaeal Group (DSAG is one of the most predominant. Despite their high abundance no members from this archaeal group have so far been characterized and thus their metabolism is unknown. Here we show that the relative abundance of DSAG marker genes can be correlated with geochemical parameters, allowing prediction of both the potential electron donors and acceptors of these organisms. We estimated the abundance of 16S rRNA genes from Archaea, Bacteria and DSAG in 52 sediment horizons from two cores collected at the slow-spreading Arctic Mid-Ocean Ridge, using qPCR. The results indicate that members of the DSAG make up the entire archaeal population in certain horizons and constitute up to ~ 50% of the total microbial community. The quantitative data were correlated to 30 different geophysical and geochemical parameters obtained from the same sediment horizons. We observed a significant correlation between the relative abundance of DSAG 16S rRNA genes and the content of organic carbon (p < 0.0001. Further, significant co-variation with iron oxide, and dissolved iron and manganese (all p < 0.0000, indicated a direct or indirect link to iron and manganese cycling. Neither of these parameters correlated with the relative abundance of archaeal or bacterial 16S rRNA genes, nor did any other major electron donor or acceptor measured. Phylogenetic analysis of DSAG 16S rRNA gene sequences reveals three monophyletic lineages with no apparent habitat-specific distribution. In this study we support the hypothesis that members of the DSAG are tightly linked to the content of organic carbon and directly or indirectly involved in the cycling of iron and/or manganese compounds. Further, we provide a molecular tool to assess their abundance in environmental samples and enrichment cultures.

  20. Reconstruction of a high-resolution late holocene arctic paleoclimate record from Colville River delta sediments.

    Energy Technology Data Exchange (ETDEWEB)

    Schreiner, Kathryn Melissa; Lowry, Thomas Stephen

    2013-10-01

    This work was partially supported by the Sandia National Laboratories,Laboratory Directed Research and Development' (LDRD) fellowship program in conjunction with Texas A&M University (TAMU). The research described herein is the work of Kathryn M. Schreiner (Katie') and her advisor, Thomas S. Bianchi and represents a concise description of Katie's dissertation that was submitted to the TAMU Office of Graduate Studies in May 2013 in partial fulfillment of her doctorate of philosophy degree. High Arctic permafrost soils contain a massive amount of organic carbon, accounting for twice as much carbon as what is currently stored as carbon dioxide in the atmosphere. However, with current warming trends this sink is in danger of thawing and potentially releasing large amounts of carbon as both carbon dioxide and methane into the atmosphere. It is difficult to make predictions about the future of this sink without knowing how it has reacted to past temperature and climate changes. This project investigated long term, fine scale particulate organic carbon (POC) delivery by the high-Arctic Colville River into Simpson's Lagoon in the near-shore Beaufort Sea. Modern POC was determined to be a mixture of three sources (riverine soils, coastal erosion, and marine). Downcore POC measurements were performed in a core close to the Colville River output and a core close to intense coastal erosion. Inputs of the three major sources were found to vary throughout the last two millennia, and in the Colville River core covary significantly with Alaskan temperature reconstructions.

  1. Testaceans (Protozoa: Testacea) in Quaternary Permafrost Sediments of Bykovsky Peninsula, Arctic Yakutia

    OpenAIRE

    Bobrov, Anatoly A.; Siegert, Christine; Andreev, Andrei A.; Schirrmeister, Lutz

    2003-01-01

    The results of the first protozoological study in terms of paleoecology of long-term sediments and buried soils formed in the cryolite zone of northeastern Siberia are discussed. The data on testaceans (Protozoa: Testacea) inhabiting various sites of Bykovsky Peninsula, Laptev Sea coast near estuary of Lena, within the last 53 000 years (Late Pleistocene and Holocene) are presented.

  2. Seismic stratigraphy and sediment thickness of the Nansen Basin, Arctic Ocean

    Science.gov (United States)

    Engen, Øyvind; Gjengedal, Jakob Andreas; Faleide, Jan Inge; Kristoffersen, Yngve; Eldholm, Olav

    2009-03-01

    A Norwegian expedition to the western Nansen Basin, Yermak Plateau and the Hinlopen margin in 2001 acquired about 1100 km of 2-D multichannel seismic profiles and 50 wide-angle sonobuoy record sections. Analysis of these data establishes a regional seismic stratigraphic framework for the western Nansen Basin integrating previously published stratigraphic schemes. P-wave velocities and sediment thickness were derived within 7-8 per cent uncertainty from 2-D seismic ray tracing models of each sonobuoy section. Sediment thickness reaches 2 km in the studied area and increases towards the depocentre of the giant Franz-Victoria fan on the Barents-Kara continental margin. High-relief oceanic crystalline crust with 3.7 km s-1 average near-top velocity is infilled by four seismic sediment units with typical velocities 2.4, 2.2, 2.0 and 1.8 km s-1. A prominent regional seismic horizon between units 2 and 3 is tentatively correlated by basement onlap and sedimentation rates to a Miocene (~10 Ma) palaeoceanographic event, possibly the opening of the Fram Strait. The youngest unit is correlated to prograding sequences on the margin and to the onset of major slope failure caused by intensified glacio-fluvial drainage and ice sheet erosion during Northern Hemisphere glaciations (2.6-0.01 Ma).

  3. Impacts of ocean acidification on sediment processes in shallow waters of the Arctic Ocean

    NARCIS (Netherlands)

    Gazeau, F.; van Rijswijk, P.; Pozzato, L.; Middelburg, J.J.

    2014-01-01

    Despite the important roles of shallow-water sediments in global biogeochemical cycling, the effects of ocean acidification on sedimentary processes have received relatively little attention. As high-latitude cold waters can absorb more CO2 and usually have a lower buffering capacity than warmer wat

  4. Impacts of Ocean Acidification on Sediment Processes in Shallow Waters of the Arctic Ocean

    NARCIS (Netherlands)

    Gazeau, F.; van Rijswijk, P.; Pozzato, L.; Middelburg, J.J.

    2014-01-01

    Despite the important roles of shallow-water sediments in global biogeochemical cycling, the effects of ocean acidification on sedimentary processes have received relatively little attention. As high-latitude cold waters can absorb more CO2 and usually have a lower buffering capacity than warmer wat

  5. Increased accumulation of sulfur in lake sediments of the high Arctic

    DEFF Research Database (Denmark)

    Drevnick, Paul E.; Muir, Derek C.G.; Lamborg, Carl H.;

    2010-01-01

    in sulfur accumulation may be due ultimately to a changing climate. Warming-induced lengthening of the ice-free season is resulting in well-documented increases in algal production and sedimentation of the resulting detrital matter. Algal detritus is a rich source of labile carbon, which in these...

  6. Detrital zircons (U-Pb and Lu-Hf) and host hemipelagic sediments (Pb-Sr-Nd-Os) from the Polar Arctic

    Science.gov (United States)

    Kapitonov, Igor; Belyatsky, Boris; Petrov, Eugeny; Sergeev, Sergey

    2015-04-01

    We studied deep-sea sediments from 6 sampling sites on the steep slopes of seamounts that accumulate during the last one million years. The goal of the study - to characterize the bedrock, which are coming to the surface from the overlying deposits for most of these steep slopes and weathering give talus deposits accumulating at the foot of the slopes.. The result proved to be similar enough for heavy fraction of all sediment columns spaced along the Alpha-Mendeleev Ridge on a 450 km. This suggest provenance similarity, which can be achieved either by erosion of the same rocks composing this ridge or by continental origin of material. We conducted control sampling of deep-water pelagic sediments in several remote places and held various positions with respect to the morphological ocean structure: on the flatten top surface of the deep-water ridge, on the bottom surface of the Amundsen Basin, 100 km to the west of the Lomonosov Ridge, at the Geophysicists Spur from the eastern side of the Lomonosov Ridge, and from the Laptev Sea. There are five control samples, which showed some local differences in the composition and distribution of zircon ages, with a total general similarity of these distributions. This fact indicates move the character of precipitation, as on the surface elevations and depressions in the sediment at the expense of local erosion of bedrock can not be formed. One of the sources of the Arctic Ocean sediments are traditionally considered «dirty» sea ice carrying material from the Canadian Archipelago, which are moved into the central part of the ocean due to Bofourt Gear flow. However, the distribution of zircon ages, revealed in the sediments, differs significantly from similar distributions for detrital zircon of Arctic coast of Alaska, the Canadian Archipelago, Greenland, Europe (Baltic Shield) and North America. But there are a lot more similarities with the zircon ages distributions typical for Asian continent, excluding China and India

  7. Zeroing tests of luminescence sediment dating in the Arctic Ocean: Review and new results from Alaska-margin core tops and central-ocean dirty sea ice

    Science.gov (United States)

    Berger, Glenn W.

    2009-07-01

    Additional numeric dating techniques are needed for sediments in the Arctic Ocean that span at least the last half million years. Almost all presently suitable geochronometers are relative-dating methods, requiring significant assumptions about sedimentation rates (such as continuous deposition and preservation). An alternative 'absolute' geochronometer, luminescence sediment dating, assumes daylight exposure of siliciclastic grains before burial. Early tests and applications of thermoluminescence (TL) techniques in the western Arctic Ocean showed some promise, but trans-ocean application to core tops of more sensitive photon-stimulated-luminescence (PSL) multi-aliquot procedures revealed large regional variations in accuracy. Recent applications of single-aliquot PSL procedures to core tops and dirty sea ice refine our understanding of the limitations and capabilities of PSL dating in this ocean. Dirty sea ice is the source of most of the bottom sediment. Particular procedures for multi-aliquot and single-aliquot PSL dating produce near-zero ages for silt grains from 4 available dirty sea-ice samples. This suggests that TL and PSL age overestimates obtained previously from core-top samples were due mainly to bottom-current reworking (mixing or stripping) of silt grains in abyssal darkness, rather than due to sedimentation of relict-age grains from sea ice. Single-aliquot PSL dating of silt grains from core tops at two different-depth sites at the Alaskan margin reveals large variations in accuracy. This re-emphasizes the critical sensitivity of fine-silt PSL dating accuracy to the effects of bottom-current processes. These recent applications are beginning to provide a more precise knowledge of just where and how PSL methods are likely to be accurate in the Arctic Ocean.

  8. Sonobuoy-based velocity functions for sediment thickness calculation in the deep Canada Basin of the Arctic Ocean

    Science.gov (United States)

    Lebedeva-Ivanova, N. N.; Hart, P. E.; Chian, D.; Shimeld, J.; Lizarralde, D.; Hutchinson, D. R.; Mosher, D. C.

    2012-12-01

    The deep Canada Basin, which occupies much of the western (Amerasian) Arctic Ocean, is one of the most unexplored and difficult areas on Earth for marine seismic acquisition due to permanent sea ice cover. It extends northward from the Alaskan and Canadian margins for ~500 km and is characterized by a remarkably flat sea floor at 3.6-3.8 km below sea level (bsl) and covers ~500,000 km^2. A set of 143 sonobuoy records were collected during 2007-2010 over the Canada Basin by US-Canada collaborative expeditions. The sonobuoys were deployed along short streamer multi-channel seismic (MCS) lines for estimating seismic velocities in the sediments. A spatial coverage of sonobuoys at every ~80 km on MCS lines provides data for robust average empirical time-depth conversion functions.Sediments are nearly sub-horizontal and sub-parallel, mostly undisturbed with maximum two-way travel time (TWTT)thicknesses of ~5 s, but not greater than ~2.5-3.0 s TWTT closer to the Alpha Ridge and the Chukchi Borderland. Semblance velocity analysis has been applied to the sonobuoy records to determine sediment thickness and depth using the Dix equation. Assuming flat-lying sediments, the normal-moveout (NMO) velocity is approximately equal to the root-mean-square (RMS) average velocity from the sea surface to the reflection horizon. A dip of 5 degrees effects velocity less than 0.5%. Semblance velocity analyses were completed for 128 of 143 sonobuoy records in the deep Canada Basin; 25 records were excluded from later analysis due to bad quality or location on the slope. Results were also converted to interval velocities and depths.The RMS velocities were consistently picked from clear high-coherency events to yield only increasing interval velocities.Picking stopped at or above the bright reflection interpreted as basement on the MCS. Velocities were not picked on dipping reflections surfaces, along the margins where the seafloor was dipping, nor for sedimentary horizons characterized by

  9. Anoxic carbon degradation in Arctic sediments: Microbial transformations of complex substrates

    DEFF Research Database (Denmark)

    Arnosti, Carol; Finke, Niko; Larsen, Ole;

    2005-01-01

    Complex substrates are degraded in anoxic sediments by the concerted activities of diverse microbial communities. To explore the effects of substrate complexity on carbon transformations in permanently cold anoxic sediments, four substrates—Spirulina cells, Isochrysis cells, and soluble high...... of carbon degradation diverged, with an additional 43%, 32%, 33%, and 8% of Isochrysis, Iso-Ex, Spirulina, and Spir-Ex carbon respired to CO2 over the next 750 h of incubation. Somewhat surprisingly, the soluble, carbohydrate-rich extracts did not prove to be more labile substrates than the whole...... cells from which they were derived. Although Spirulina and Iso-Ex differed in physical and chemical characteristics (solid/soluble, C/N ratio, lipid and carbohydrate content), nearly identical quantities of carbon were respired to CO2. In contrast, only 15% of Spir-Ex carbon was respired, despite the...

  10. Lignin as an indicator of the sedimentation conditions on the Arctic shelf

    Science.gov (United States)

    Ulyantsev, A. S.; Romankevich, E. A.; Peresypkin, V. I.; Belyaev, N. A.; Semiletov, I. P.; Bratskaya, S. Yu.; Vetrov, A. A.; Sergienko, V. I.

    2016-03-01

    It is shown for the first time that the proportion of lignin in shelf deposits may range from 1/3 to the total concentration of organic carbon. The distribution of wood residues and lignin in the studied sedimentary formation is very uneven, which reflects the dynamic flux environment of sedimentation and OM supply. The calculated molecular indexes showed that most of the OM in deposits underwent insignificant diagenetic alterations.

  11. Walruses recovering after 60+ years of protection in Svalbard, Norway

    Directory of Open Access Journals (Sweden)

    Kit M. Kovacs

    2014-10-01

    Full Text Available Walruses were brought to the brink of extinction in Svalbard (Norway during 350 years of unregulated harvesting. They became protected in 1952, when few remained. During the first 30 years of protection, approximately 100 animals became established within the archipelago, most of which likely came from Franz Josef Land, to the east. A marked recovery has taken place since then. This study reports the results of a photographic aerial survey flown in summer 2012, covering all current and historical haul-out sites for walruses in Svalbard. It provides updates regarding the increasing numbers of: (1 land-based haul-out sites (from 78 in 2006 to 91 in 2012; (2 occupied sites (from 17 in 2006 to 24 in the 2012 survey; (3 sites with mother–calf pairs (which increased from a single site with a single small calf in 2006 to 10 sites with a total of 57 small calves in 2012 and; (4 a 48% increase in abundance in the six-year period between the two surveys to 3886 (confidence interval 3553–4262 animals, including animals in the water at the time of the survey. Future environmental change might reduce benthic production in the Arctic, reducing the prey-base for walruses, and also impact walruses directly via declines in their sea-ice breeding habitat. But, currently the Svalbard walrus population is growing at a rate that matches the theoretical maximum rate of growth that has been calculated for recovering walrus populations under favourable environmental conditions with no food limitations.

  12. Distribution of PAHs and the PAH-degrading bacteria in the deep-sea sediments of the high-latitude Arctic Ocean

    Science.gov (United States)

    Dong, C.; Bai, X.; Sheng, H.; Jiao, L.; Zhou, H.; Shao, Z.

    2015-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are common organic pollutants that can be transferred long distances and tend to accumulate in marine sediments. However, less is known regarding the distribution of PAHs and their natural bioattenuation in the open sea, especially the Arctic Ocean. In this report, sediment samples were collected at four sites from the Chukchi Plateau to the Makarov Basin in the summer of 2010. PAH compositions and total concentrations were examined with GC-MS. The concentrations of 16 EPA-priority PAHs varied from 2.0 to 41.6 ng g-1 dry weight and decreased with sediment depth and movement from the southern to the northern sites. Among the targeted PAHs, phenanthrene was relatively abundant in all sediments. The 16S rRNA gene of the total environmental DNA was analyzed with Illumina high-throughput sequencing (IHTS) to determine the diversity of bacteria involved in PAH degradation in situ. The potential degraders including Cycloclasticus, Pseudomonas, Halomonas, Pseudoalteromonas, Marinomonas, Bacillus, Dietzia, Colwellia, Acinetobacter, Alcanivorax, Salinisphaera and Shewanella, with Dietzia as the most abundant, occurred in all sediment samples. Meanwhile, enrichment with PAHs was initiated onboard and transferred to the laboratory for further enrichment and to obtain the degrading consortia. Most of the abovementioned bacteria in addition to Hahella, Oleispira, Oceanobacter and Hyphomonas occurred alternately as predominant members in the enrichment cultures from different sediments based on IHTS and PCR-DGGE analysis. To reconfirm their role in PAH degradation, 40 different bacteria were isolated and characterized, among which Cycloclasticus Pseudomonas showed the best degradation capability under low temperatures. Taken together, PAHs and PAH-degrading bacteria were widespread in the deep-sea sediments of the Arctic Ocean. We propose that bacteria of Cycloclasticus, Pseudomonas, Pseudoalteromonas, Halomonas, Marinomonas and Dietzia may

  13. Distribution of PAHs and the PAH-degrading bacteria in the deep-sea sediments of the high-latitude Arctic Ocean

    Directory of Open Access Journals (Sweden)

    C. Dong

    2014-09-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are persistent organic pollutants, which can be transferred to a long distance and tend to accumulation in marine sediment. However, PAHs distribution and natural bioattenuation is less known in open sea, especially in the Arctic Ocean. In this report, sediment samples were collected at four sites from the Chukchi Plateau to Makarov Basin in the summer of 2010. PAH composition and total concentrations were examined with GC-MS, we found that the concentrations of 16 EPA-priority PAHs varied from 2.0 to 41.6 ng g−1 dry weight in total and decreased with sediment depths and as well as from the southern to northern sites. Among the targeted PAHs, phenanthrene was relatively abundant in all sediments. To learn the diversity of bacteria involved in PAHs degradation in situ, the 16S rRNA gene of the total environmental DNA was analyzed with Illumina high throughput sequencing (IHTS. In all the sediments, occurred the potential degraders including Cycloclasticus, Pseudomonas, Halomonas, Pseudoalteromonas, Marinomonas, Bacillus, Dietzia, Colwellia, Acinetobacter, Alcanivorax, Salinisphaera and Shewanella, with Dietzia as the most abundant. Meanwhile on board, enrichment with PAHs was initiated and repeated transfer in laboratory to obtain the degrading consortia. Most above mentioned bacteria in addition to Hahella, Oleispira, Oceanobacter and Hyphomonas, occurred alternately as a predominant member in enrichment cultures from different sediments, as revealed with IHTS and PCR-DGGE. To reconfirm their role in PAH degradation, 40 different bacteria were isolated and characterized, among which Cycloclasticus and Pseudomonas showed the best degradation capability under low temperature. Taken together, PAHs and PAH-degrading bacteria were widespread in the deep-sea sediments of the Arctic Ocean. We propose that bacteria of Cycloclasticus, Pseudomonas, Pseudoalteromonas, Halomonas, Marinomonas and Dietzia may play the

  14. Distribution of PAHs and the PAH-degrading bacteria in the deep-sea sediments of the high-latitude Arctic Ocean

    Science.gov (United States)

    Dong, C.; Bai, X.; Sheng, H.; Jiao, L.; Zhou, H.; Shao, Z.

    2014-09-01

    Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants, which can be transferred to a long distance and tend to accumulation in marine sediment. However, PAHs distribution and natural bioattenuation is less known in open sea, especially in the Arctic Ocean. In this report, sediment samples were collected at four sites from the Chukchi Plateau to Makarov Basin in the summer of 2010. PAH composition and total concentrations were examined with GC-MS, we found that the concentrations of 16 EPA-priority PAHs varied from 2.0 to 41.6 ng g-1 dry weight in total and decreased with sediment depths and as well as from the southern to northern sites. Among the targeted PAHs, phenanthrene was relatively abundant in all sediments. To learn the diversity of bacteria involved in PAHs degradation in situ, the 16S rRNA gene of the total environmental DNA was analyzed with Illumina high throughput sequencing (IHTS). In all the sediments, occurred the potential degraders including Cycloclasticus, Pseudomonas, Halomonas, Pseudoalteromonas, Marinomonas, Bacillus, Dietzia, Colwellia, Acinetobacter, Alcanivorax, Salinisphaera and Shewanella, with Dietzia as the most abundant. Meanwhile on board, enrichment with PAHs was initiated and repeated transfer in laboratory to obtain the degrading consortia. Most above mentioned bacteria in addition to Hahella, Oleispira, Oceanobacter and Hyphomonas, occurred alternately as a predominant member in enrichment cultures from different sediments, as revealed with IHTS and PCR-DGGE. To reconfirm their role in PAH degradation, 40 different bacteria were isolated and characterized, among which Cycloclasticus and Pseudomonas showed the best degradation capability under low temperature. Taken together, PAHs and PAH-degrading bacteria were widespread in the deep-sea sediments of the Arctic Ocean. We propose that bacteria of Cycloclasticus, Pseudomonas, Pseudoalteromonas, Halomonas, Marinomonas and Dietzia may play the most important role

  15. Organophosphorous flame retardants in biota from Svalbard, Norway.

    Science.gov (United States)

    Hallanger, Ingeborg G; Sagerup, Kjetil; Evenset, Anita; Kovacs, Kit M; Leonards, Pim; Fuglei, Eva; Routti, Heli; Aars, Jon; Strøm, Hallvard; Lydersen, Christian; Gabrielsen, Geir Wing

    2015-12-15

    Eight arctic species, including fish, birds and mammals, from diverse habitats (marine and terrestrial) within the Svalbard Archipelago, Norway, were screened for 14 organophosphorus flame retardant (PFR) compounds. Ten PFRs were detected: tris(2-chloroethyl)phosphate (TCEP), tris(2-chloroisopropyl)phosphate (TCIPP), tris(1,3-dichloro-2-propyl)phosphate (TDCIPP), triphenyl phosphate (TPHP); 2-ethylhexyl diphenyl phosphate (EHDPP); tris(2-butoxyethyl)phosphate (TBOEP); tritolyl phosphate (TCrP); triisobutyl phosphate (TIBP); tris(2-ethylhexyl)phosphate (TEHP); and butyl diphenyl phosphate (DPhBP). The greatest number of different PFR compounds, and the highest detection frequency were measured in capelin (Mallotus villotus), and the lowest in Brünnich's guillemot (Uria lomvia). The highest concentrations of ΣPFR, as well as the highest concentration of a single PFR compound, TBOEP, were measured in arctic fox (Vulpes lagopus). The presence of PFR compounds in arctic biota indicates that these compounds can undergo long-range transport and are, to some degree, persistent and bioaccumulated. The potential for biomagnification from fish to higher trophic levels seems to be limited. PMID:26453403

  16. Latitudinal trends in fluxes and congener patterns of PCBs inferred from lake sediment cores from mid-latitude and Arctic Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Muir, D.; Omelchenko, A.; Grift, N.; Lockhart, L.; Wilkinson, P.; Brunskill, G. [Department of Fisheries and Oceans, Winnipeg, Manitoba (Canada). Freshwater Inst.; Robbins, J.A. [NOAA, Ann Arbor, MI (United States). Great Lakes Environmental Research Lab.

    1995-12-31

    Sediment cores collected from 9 remote lakes in central and Arctic Canada (49{degree}N to 82{degree}N and from 71{degree} to 136{degree}W) were analyzed for PCBs with the objective of examining latitudinal and temporal trends in deposition. Core slices (1--1.3 cm) were dated with {sup 210}Pb and {sup 137}Cs using the Robbins rapid steady-state mixing model and sediment focusing factors were determined with the aid of soil cores or predictions of historical radionuclide deposition. Slices were freeze-dried, Soxhlet extracted with DCM and chromatographed on Florisil, then analyzed by high resolution GC-ECD with confirmation by GC-HRMS. {Sigma}PCB concentrations in surface sediments were low ranging from 8 to 40 ng{center_dot}g{sup {minus}1} (dry wt) in southern mid-continental sites (49--63{degree}N) to 2 ng{center_dot}g{sup {minus}1} in Lake Hazen, the most northerly location (82{degree}N). Highest concentrations were found in the most recent slices (1980s) of cores from high Arctic lakes (at 75 and 82{degree}N) whereas peak concentrations were reached earlier (in the 1970s) at more southerly locations. Principal components analysis revealed that sediments from high Arctic lakes could be distinguished by greater proportions of lower chlorinated PCBs in comparison with published results for Lakes Ontario and Superior. Focus corrected {Sigma}PCBs fluxes ranged from 305 to 920 ng{center_dot}m{sup 2}{center_dot}yr{sup {minus}1} in the 9 lakes and were negatively correlated with latitude (r{sup 2} = 0.53). Fluxes of Cl{sup 8} CBs had a strong negative correlation with latitude (r2 = 0.88) while Cl{sup 3} CBs showed no latitudinal trend. The results generally support several of the predictions of the cold condensation hypothesis.

  17. Estimating the daily dry matter intake of Svalbard reindeer in late winter

    Directory of Open Access Journals (Sweden)

    Nicholas Tyler

    1987-06-01

    Full Text Available Svalbard reindeer (Rangifer tarandus platyrhynchus store large reserves of subcutaneous fat during summer and autumn which, it has been suggested, might be sufficient to meet a substantial part of their energy requirements during winter. An alternative suggestion, however, is that fat is not their main source of energy after all and, moreover, that the principal role of their fat reserves is for enhancing reproductive success rather than for substituting for forage (Tyler, in press. Is it realistic to suggest that these high arctic herbivores could meet the greater part of their energy requirements in winter by feeding, given that the aerial biomass of available forage in Svalbard in late winter is very low? This question was investigated by using a simple model to predict what rate of food intake Svalbard reindeer would have to achieve to maintain energy balance in late winter. The results were surprisingly low: pregnant and nonpregnant females could mett their daily energy demands by consuming 3.1 and 1.7 g dry matter per grazing minute, respectively. This supports the suggestion that Svalbard reindeer could live principally off forage in winter.

  18. Controls on stable sulfur isotope fractionation during bacterial sulfate reduction in Arctic sediments

    DEFF Research Database (Denmark)

    Bruchert, V.; Knoblauch, C.; Jørgensen, BB

    2001-01-01

    -specific sulfate reduction rates, these greater isotopic differences cannot be accounted for by significantly lower in situ bacterial sulfate reduction rates. Therefore, the remaining isotopic difference between sulfate and sulfide must derive from additional isotope effects that exist in the oxidative part of the...... fractionations varied by less than 5.8 parts per thousand with respect to temperature and sulfate reduction rate, whereas the difference in sulfur isotopic fractionation between bacteria with different carbon oxidation pathways was as large as 17.4 parts per thousand. Incubation of sediment slurries from two...... parts per thousand and 8 parts per thousand above 25 degreesC, respectively. In absence of significant differences in sulfate reduction rates in the high and low temperature range, respectively, we infer that different genera of sulfate-reducing bacteria dominate the sulfate-reducing bacterial community...

  19. Reduced metabolic cost of locomotion in Svalbard rock ptarmigan (Lagopus muta hyperborea during winter.

    Directory of Open Access Journals (Sweden)

    John Lees

    Full Text Available The Svalbard rock ptarmigan, Lagopus muta hyperborea experiences extreme photoperiodic and climatic conditions on the Arctic archipelago of Svalbard. This species, however, is highly adapted to live in this harsh environment. One of the most striking adaptations found in these birds is the deposition, prior to onset of winter, of fat stores which may comprise up to 32% of body mass and are located primarily around the sternum and abdominal region. This fat, while crucial to the birds' survival, also presents a challenge in that the bird must maintain normal physiological function with this additional mass. In particular these stores are likely to constrain the respiratory system, as the sternum and pelvic region must be moved during ventilation and carrying this extra load may also impact upon the energetic cost of locomotion. Here we demonstrate that winter birds have a reduced cost of locomotion when compared to summer birds. A remarkable finding given that during winter these birds have almost twice the body mass of those in summer. These results suggest that Svalbard ptarmigan are able to carry the additional winter fat without incurring any energetic cost. As energy conservation is paramount to these birds, minimising the costs of moving around when resources are limited would appear to be a key adaptation crucial for their survival in the barren Arctic environment.

  20. Distinct summer and winter bacterial communities in the active layer of Svalbard permafrost revealed by DNA- and RNA-based analyses

    DEFF Research Database (Denmark)

    Schostag, Morten; Stibal, Marek; Jacobsen, Carsten S.;

    2015-01-01

    The active layer of soil overlaying permafrost in the Arctic is subjected to dramatic annual changes in temperature and soil chemistry, which likely affect bacterial activity and community structure. We studied seasonal variations in the bacterial community of active layer soil from Svalbard (78º...

  1. Input of Terrestrial Palynomorphs since the Last Deglaciation from Sediments of the Chukchi Sea Shelf, Western Arctic Ocean

    Science.gov (United States)

    Delusina, I.; Kim, S. Y.; Nam, S. I.; Woo, K. S.

    2014-12-01

    We report the palynology of marine sediment core ARA02B/01A-GC from the Western margin of the shallow shelf of the Chukchi Sea in the Arctic, a site which was synchronously influenced by climatic changes during the last deglaciation with those in the Bering Strait. The core contains a rich concentration of continental palynomorphs, even though the coring location is quite a distance from land. The catchment area for the observed palynomorphs includes the territories of both North America (Alaska and North Canada) and Northern Siberia (Chukotka peninsula and Northern East-Siberian coast). Based on this fact, we can reconstruct a common paleoenvironmental history for this location and the Bering Strait during the postglacial interval. We hypothesize that palynomorphs were carried to the sea during low sea-ice coverage intervals by large rivers (Yukon, Mackenzie and Siberian rivers) and were then transferred by oceanic currents. During intervals of extensive sea-ice coverage the source of the palynomorphs was predominantly eroded shelf sediments. The percentage ratio of tree-herb pollen and spores in the palynomorph assemblages shows that favorable conditions for an increase in forest vegetation took place between ~8 and 4 kyr BP, which coincides with maximum freshwater input to the sea. During a climatic optimum at ~5 kyr BP, as inferred from the total dominance of tree and herb pollen, the Chukchi Sea was apparently warmer than today. This represents the maximum ice-free period for the sea. The low sea-ice interval ended ~3 kyr BP, as suggested by a sharp drop in tree pollen, a reduction in fresh water input, and a drop in the concentration of the algae Pediastrum. Our data correlate well with data from marine core HLY0501-5 from the Bering Strait (Polyak et al., 2009) for the interval of 10-8 kyr BP, but shows a divergence since ~4 kyr BP, which may correspond to the beginning of the differentiation of North American and East-Siberian ecosystem zones.

  2. Generalized Geology of Svalbard (geo_sval)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This coverage includes arcs, polygons, and polygon labels that describe the generalized geologic age of surface outcrops of bedrock of Svalbard. It also includes...

  3. Large-scale ice thickness distribution of first-year sea ice in spring and summer north of Svalbard

    OpenAIRE

    Renner, Angelika; Hendricks, Stefan; Gerland, Sebastian; Beckers, Justin M.; Haas, Christian; Krumpen, Thomas

    2013-01-01

    The large-scale thickness distribution of sea ice was measured during several campaigns in the European Arctic north of Svalbard from 2007 using an airborne electromagnetic induction device. In August 2010 and April–May 2011, this was complemented by extensive on-ice work including measurements of snow thickness and freeboard. Ice thicknesses show a clear difference between the seasons, with thicker ice during spring than in summer. In spring 2011, negative freeboard and flooding were observe...

  4. Bioluminescence in the high Arctic during the polar night

    OpenAIRE

    Berge, Jørgen; Båtnes, Anna Solvang; Johnsen, Geir; Blackwell, Susan; Mark A. Moline

    2012-01-01

    This study examines the composition and activity of the planktonic community during the polar night in the high Arctic Kongsfjord, Svalbard. Our results are the first published evidence of bioluminescence among zooplankton during the Arctic polar night. The observations were collected by a bathyphotometer detecting bioluminescence, integrated into an autonomous underwater vehicle, to determine the concentration and intensity of bioluminescent flashes as a function of time of day and depth. To...

  5. Late Quaternary sea-ice history of northern Fram Strait/Arctic Ocean

    Science.gov (United States)

    Kremer, Anne; Stein, Rüdiger; Fahl, Kirsten; Matthießen, Jens; Forwick, Matthias; O'Regan, Matt

    2016-04-01

    One of the main characteristics of the Arctic Ocean is its seasonal to perennial sea-ice cover. Variations of sea-ice conditions affect the Earth's albedo, primary production, rate of deep-water etc.. During the last decades, a drastic decrease in sea ice has been recorded, and the causes of which, i.e., natural vs. anthropogenic forcings, and their relevance within the global climate system, are subject of intense scientific and societal debate. In this context, records of past sea-ice conditions going beyond instrumental records are of major significance. These records may help to better understand the processes controlling natural sea-ice variability and to improve models for forecasts of future climatic conditions. During RV Polarstern Cruise PS92 in summer 2015, a 860 cm long sediment core (PS92/039-2) was recovered from the eastern flank of Yermak Plateau north of the Svalbard archipelago (Peeken, 2015). Based on a preliminary age model, this sediment core probably represents the time interval from MIS 6 to MIS 1. This core, located close to the modern summer ice edge, has been selected for reconstruction of past Arctic sea-ice variability based on specific biomarkers. In this context, we have determined the ice-algae-derived sea-ice proxy IP25 (Belt et al., 2007), in combination with other biomarkers indicative for open-water conditions (cf., Müller et al., 2009, 2011). Furthermore, organic carbon fluxes were differentiated using specific biomarkers indicative for marine primary production (brassicasterol, dinosterol) and terrigenous input (campesterol, β-sitosterol). In this poster, preliminary results of our organic-geochemical and sedimentological investigations are presented. Distinct fluctuations of these biomarkers indicate several major, partly abrupt changes in sea-ice cover in the Yermak Plateau area during the late Quaternary. These changes are probably linked to changes in the inflow of Atlantic Water along the western coastline of Svalbard into

  6. Climatology of aerosol optical properties in Northern Norway and Svalbard

    Directory of Open Access Journals (Sweden)

    Y.-C. Chen

    2012-10-01

    Full Text Available We present comparisons between estimates of the aerosol optical thickness and the Ångström exponent in Northern Norway and Svalbard based on data from AERONET stations at Andenes (69° N, 16° E, 379 m altitude and Hornsund (77° N, 15° E, 10 m altitude for the period 2008–2010. The three-year annual mean values for the aerosol optical thickness at 500 nm τ(500 at Andenes and Hornsund were 0.11 and 0.10, respectively. At Hornsund, there was less variation of the monthly mean value of τ(500 than at Andenes. The annual mean values of the Ångström exponent α at Andenes and Hornsund were 1.18 and 1.37, respectively. At Andenes and Hornsund α was found to be larger than 1.0 in 68% and 93% of the observations, respectively, indicating that fine-mode particles were dominating at both sites. Both sites had a similar seasonal variation of the aerosol size distribution although one site is in an Arctic area while the other site is in a sub-arctic area.

  7. Selective processes for bioaccumulative up-take of persistent organic pollutants (POPs) in Arctic food webs

    OpenAIRE

    Carlsson, Pernilla Marianne

    2013-01-01

    The overall aim of the present study was to elucidate selective environmental up-take processes in Arctic food webs that lead to the bioaccumulation of persistent organic pollutants (POP) in food items consumed by Arctic indigenous people. In addition, this study aimed to increase the scientific understanding of the principles behind climate change related influences on transport processes of contaminants. Svalbard and Nuuk, Greenland were chosen as study areas since they represent Arctic con...

  8. Western Arctic Vulnerability to Warming over the past 3.6 Myr: Lessons from sediments drilled at Lake El'gygytgyn, Western Beringia

    Science.gov (United States)

    Brigham-Grette, J.; Melles, M.; Minyuk, P.; Lake El'gygytgyn Science Team

    2011-12-01

    International Continental Deep drilling (ICDP) at Lake El'gygytgyn (67_30' N, 172_05' E; "Lake E"), recovered lacustrine sediments dating back to 3.6 Ma that provides the first time-continuous Pliocene-Pleistocene paleoclimate record of different interglacials from the terrestrial Arctic. While discontinuous, spatially diverse Pliocene and Pleistocene marine interglacial records are known from the arctic borderlands at the outcrop scale, the Lake El'gygytgyn record is critically important understanding the western Arctic landscape response to different forcing factors operating across the Arctic since the mid-Pliocene warm period. The record is important for evaluating the sensitivity of the Arctic region and to provide a template of Arctic climate variability that can be compared to other regions. Lake E modeling is framed around suites of sensitivity tests of Beringian climate response to the full range of forcing experienced over the last ~3.5 million years using a nested Global-Regional Climate Model (GCM-RCM). The Pliocene portion of the lake record (~3.6-3.0 Ma; a time when atmospheric CO2 levels may have been like today) has nearly twice the sedimentation rate as later Quaternary intervals, partly as a consequence of basin infilling but also presumably due to more rainfall and more active rivers at that time. Studies of spores and pollen from this portion of the core (samples every ~10k) show that the area was once dominated by trees, providing us with the pace of variability in Pliocene Arctic forests, which included species of pine, larch, spruce, fir, alder, and hemlock. Hemlock and tree pine pollen is exceptional for this latitude but the assemblage implies July temperatures nearly 8 degrees warmer than today with ~3 times the annual precipitation. Modeling suggests sustained forests at Lake E in both cold and warm orbits during this interval. The record includes a strong M2 cooling event to conditions like today at ~3.3 Ma, but not glacial climates as

  9. Erosion of soil organic carbon at high latitudes and its delivery to Arctic Ocean sediments: New source to sink insight from radiocarbon dating

    Science.gov (United States)

    Hilton, Robert; Galy, Valier; Gaillardet, Jerome; Dellinger, Mathieu; Bryant, Charlotte; O'Regan, Matt; Grocke, Darren; Coxall, Helen

    2016-04-01

    Soils of the northern high latitudes store carbon over thousands of years and contain almost double the carbon stock of the atmosphere. Erosion processes can mobilise this pre-aged soil organic carbon from the landscape and supply it to rivers. If it escapes degradation during river transport and is delivered to the coastal ocean, this carbon may be sequestered for much longer periods of time (>104 yr) as a geological CO2 sink. Despite this recognition, the erosional flux and fate of particulate organic carbon (POC) in large rivers draining the high latitudes remains poorly constrained. Using radiocarbon activity, we quantify POC source, flux and fate in the Mackenzie River, the main sediment supplier to the Arctic Ocean. When combined with stable carbon isotopes and element ratios, the radiocarbon activity of POC allows us to distinguish inputs of POC from sedimentary rocks and quantify the average age of biospheric POC (from vegetation and soil) transported through the river system. We find that the eroded biospheric POC has resided in the basin for millennia, with a mean radiocarbon age of 5800±800 years. This is much older than large tropical rivers where we have equivalent data (Amazon River, Ganges River), and likely reflects the longer residence time of organic matter in cold, wet, high latitude soils. Based on the measured biospheric POC content and annual sediment flux, we calculate a biospheric POC flux of 2.2 (+1.3/-0.9) TgC yr‑1 from the Mackenzie River. This is the largest input of aged organic carbon to the Arctic Ocean, more than the combined POC flux from the Eurasian Rivers. Offshore, we use a marine core to investigate organic carbon burial over the Holocene period. Radiocarbon measurements of bulk organic carbon reveal a significant offset from benthic foraminifera radiocarbon ages throughout the core, which is dependent upon the grain size of the sediments. Organic matter in sediments >63μm are offset from foraminifera by ˜ 6,000 14C years

  10. Carboniferous non-marine source rocks from Spitsbergen and Bjoernoeya: comparison with the Western Arctic

    Energy Technology Data Exchange (ETDEWEB)

    van Koeverden, J.H.; Karlsen, D.A.; Backer-Owe, K. [University of Oslo, Oslo (Norway). Dept. of Geoscience

    2011-01-15

    In this paper, we demonstrate that Carboniferous coaly and lacustrine strata have significant liquid hydrocarbon potential in an area extending from the Norwegian Barents Sea in the east to the Canadian Arctic in the west. Organic geochemical analyses were conducted on seven coals and coaly shales from the islands of Spitsbergen (Svalbard archipelago) and Bjpernoeya (Norwegian Barents Sea). The results were interpreted in the context of published data from the two areas, and of time-equivalent non-marine successions on the Finnmark Platform (Norwegian Barents Sea), East Greenland, and the Sverdrup Basin (Canadian Arctic). In each of these areas, a warm and humid climate, together with the onset of rifting on the northern Pangea margin, facilitated the deposition and preservation of organic-rich non-marine sediments on a regional scale. All of the sediments have an elevated content of liptinitic macerals, dominated by alginite or sporinite. In the studied areas, the prolific younger source rocks which may be common in adjacent regions are often immature or absent. The identification of Carboniferous terrestrial strata with source rock potential may therefore enhance the petroleum potential of the studied regions.

  11. Seasonal differences in jump performance in the Svalbard rock ptarmigan (Lagopus muta hyperborea

    Directory of Open Access Journals (Sweden)

    John J. Lees

    2014-07-01

    Full Text Available Fat storage is essential to the survival of many bird species, providing energy reserves, but can have an effect on locomotor performance with an associated potential increase in predation risk. In particular, the ability to initiate flight through jumping is critical to predator avoidance and may be influenced by changes in body mass (Mb. Here we investigate seasonal differences in the jump take-off performance of high Arctic Svalbard rock ptarmigan (Lagopus muta hyperborea resulting from around a 50% increase in Mb during winter as a result of fat deposition. Using force-plate data and videography, we reveal that, in the absence of alterations to take-off angle, winter Svalbard rock ptarmigan are unable to increase hind-limb power output during jumping to compensate for their increased Mb. As a result, peak take-off velocity is reduced by 42% and jump duration is also extended during winter. The consequences of reduced jumping performance upon Svalbard ptarmigan during winter may be relatively small given their low risk of predation during this season. It may be, however, that the observed reduction in jumping performance when fat may contribute to the sub-maximal pattern of fat acquisition observed in other bird species.

  12. The freshwater fern Azolla (Azollaceae) from Eocene Arctic and Nordic Sea sediments: New species and their stratigraphic distribution

    NARCIS (Netherlands)

    van der Burgh, J.; Collinson, M.E.; van Konijnenburg-van Cittert, J.H.A.; Barke, J.; Brinkhuis, H.

    2013-01-01

    Three new species of the freshwater fern Azolla are described from Eocene marine deposits of the Arctic and Nordic seas, bringing the total number of species now documented from these areas to five. Azolla arctica Collinson et al., Azolla jutlandica Collinson et al., Azolla nova sp. nov. and Azolla

  13. Modern and historical fluxes of halogenated organic contaminants to a lake in the Canadian arctic, as determined from annually laminated sediment cores.

    Science.gov (United States)

    Stern, G A; Braekevelt, E; Helm, P A; Bidleman, T F; Outridge, P M; Lockhart, W L; McNeeley, R; Rosenberg, B; Ikonomou, M G; Hamilton, P; Tomy, G T; Wilkinson, P

    2005-04-15

    Two annually laminated cores collected from Lake DV09 on Devon Island in May 1999 were dated using 210Pb and 137Cs, and analyzed for a variety of halogenated organic contaminants (HOCs), including polychlorinated biphenyls (PCBs), organochlorine pesticides, short-chain polychlorinated n-alkanes (sPCAs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs). Dry weight HOC concentrations in Lake DV09 sediments were generally similar to other remote Arctic lakes. Maximum HOC fluxes often agreed well with production maxima, although many compound groups exhibited maxima at or near the sediment surface, much later than peak production. The lower than expected HOC concentrations in older sediment slices may be due to anaerobic degradation and possibly to dilution resulting from a temporary increase in sedimentation rate observed between the mid-1960s and 1970s. Indeed, temporal trends were more readily apparent for those compound classes when anaerobic metabolites were also analyzed, such as for DDT and toxaphene. However, it is postulated here for the first time that the maximum or increasing HOC surface fluxes observed for many of the major compound classes in DV09 sediments may be influenced by climate variation and the resulting increase in algal primary productivity which could drive an increasing rate of HOC scavenging from the water column. Both the fraction (F(TC)) and enantiomer fraction (EF) of trans-chlordane (TC) decreased significantly between 1957 and 1997, suggesting that recent inputs to the lake are from weathered chlordane sources. PCDD/Fs showed a change in sources from pentachlorophenol (PeCP) in the 1950s and 1960s to combustion sources into the 1990s. Improvements in combustion technology may be responsible for the reducing the proportion of TCDF relative to OCDD in the most recent slice. PMID:15866277

  14. Preliminary Chronostratigraphy of Pingualuit Impact Crater Lake Sediments (Nunavik, Canada): a Possible Arctic Terrestrial Record of Several Glacial/Interglacial Cycles

    Science.gov (United States)

    St-Onge, G.; Guyard, H.; Pienitz, R.; Hausmann, S.; Salonen, V.; Luoto, T.; Francus, P.; Larocque, I.; Lavoie, M.; Lamothe, M.; Vincent, W. F.; Niederreiter, R.

    2007-12-01

    The Pingualuit Crater Lake is a 1.4 Ma perfectly circular depression. It is 3.4 km in diameter and hosts a lake with a maximum depth of 267 m with no surface connection to other surrounding water bodies. It is located in the northernmost part of the Ungava Peninsula in Nunavik, Canada (61°N, 73°W) and, due to its unique morphometry (shape, depth), the lake bottom may have escaped glacial erosion, possibly preserving a continuous Arctic terrestrial record of several glacial/interglacial cycles. Previous attempts to core the lake have resulted in the collection of only 14 cm of sediments that spanned about the last ~5000 years. Here, in order to test the possible accumulation of several glacial/interglacial cycles, we will present initial high resolution physical (CAT-scan, Multi Sensor Core Logger, color reflectance, high resolution digital images), magnetic (point source magnetic susceptibility) and sedimentological (detailed visual description, grain size) properties of about 10 m of sediments recently cored using a UWITEC piston percussion corer under harsh climatic conditions. The initial results revealed the presence of at least two decimetre-thick intervals composed of laminated, dark grey clayey silts characterized by a relatively low density and magnetic susceptibility that contrast sharply with the thicker and more abundant over- and underlying light grey, denser, sandy sediments. The sediment characteristics in the darker laminated intervals are also similar to the ones observed in the small surface gravity core sampled at the same site. Moreover, smear slides performed in these two intervals revealed the presence of diatoms and chrysophytes, suggesting that these two intervals represent ice-free conditions and thus possible interglacials, whereas the more abundant light grey and more sandy sediments likely reflect glacial intervals. This interpretation will be tested by ongoing paleomagnetic measurements (i.e., magnetostratigraphy), as well as

  15. Modern and historical fluxes of halogenated organic contaminants to a lake in the Canadian arctic, as determined from annually laminated sediment cores

    International Nuclear Information System (INIS)

    Two annually laminated cores collected from Lake DV09 on Devon Island in May 1999 were dated using 210Pb and 137Cs, and analyzed for a variety of halogenated organic contaminants (HOCs), including polychlorinated biphenyls (PCBs), organochlorine pesticides, short-chain polychlorinated n-alkanes (sPCAs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs). Dry weight HOC concentrations in Lake DV09 sediments were generally similar to other remote Arctic lakes. Maximum HOC fluxes often agreed well with production maxima, although many compound groups exhibited maxima at or near the sediment surface, much later than peak production. The lower than expected HOC concentrations in older sediment slices may be due to anaerobic degradation and possibly to dilution resulting from a temporary increase in sedimentation rate observed between the mid-1960s and 1970s. Indeed, temporal trends were more readily apparent for those compound classes when anaerobic metabolites were also analyzed, such as for DDT and toxaphene. However, it is postulated here for the first time that the maximum or increasing HOC surface fluxes observed for many of the major compound classes in DV09 sediments may be influenced by climate variation and the resulting increase in algal primary productivity which could drive an increasing rate of HOC scavenging from the water column. Both the fraction (F TC) and enantiomer fraction (EF) of trans-chlordane (TC) decreased significantly between 1957 and 1997, suggesting that recent inputs to the lake are from weathered chlordane sources. PCDD/Fs showed a change in sources from pentachlorophenol (PeCP) in the 1950s and 1960s to combustion sources into the 1990s. Improvements in combustion technology may be responsible for the reducing the proportion of TCDF relative to OCDD in the most recent slice

  16. The Yermak Plateau in the Arctic Ocean in the light of reflection seismic data—implication for its tectonic and sedimentary evolution

    Science.gov (United States)

    Geissler, W. H.; Jokat, W.; Brekke, H.

    2011-12-01

    The separation of Northeast Greenland and Svalbard is the result of large-scale strike slip movements during Cenozoic times. Geological evidence for these movements can be found onshore both on North Greenland and Svalbard. However, the role of the submarine Yermak Plateau (YP) in this process is unclear. The compilation of available multichannel reflection and wide-angle seismic data give new insights into the sedimentary and crustal structure and evolution of the plateau. The flat surface of the present-day plateau is a quite young feature. Up to 2 km of Cenozoic sediments cover a rough basement, which show similarities to the rough topography and strike of geological structures of Spitsbergen Island. In some basins more than 4 km of sedimentary rocks could be mapped. The most pronounced structure is the Sverdrup Bank, which appears to be part of a larger crustal block. P-wave velocities of about 4.5 km s-1 derived from sonobuoy data indicate that its uppermost part is most probably composed of sedimentary or volcanic rocks. We have made a correlation of previously defined seismic units across the YP to outline the history of sediment deposition in the area. The existing graben structures on the plateau might have provided early shallow pathways for water exchange between the Arctic and the Atlantic Oceans. A chaotic sedimentary apron east of the Sverdrup Bank and bright reflections near the Mosby Seamount interpreted as magmatic sills suggest tectonic and magmatic events during the Miocene.

  17. Stable isotopes and Digital Elevation Models to study nutrient inputs in high-Arctic lakes

    Science.gov (United States)

    Calizza, Edoardo; Rossi, David; Costantini, Maria Letizia; Careddu, Giulio; Rossi, Loreto

    2016-04-01

    Ice cover, run-off from the watershed, aquatic and terrestrial primary productivity, guano deposition from birds are key factors controlling nutrient and organic matter inputs in high-Arctic lakes. All these factors are expected to be significantly affected by climate change. Quantifying these controls is a key baseline step to understand what combination of factors subtends the biological productivity in Arctic lakes and will drive their ecological response to environmental change. Basing on Digital Elevation Models, drainage maps, and C and N elemental content and stable isotope analysis in sediments, aquatic vegetation and a dominant macroinvertebrate species (Lepidurus arcticus Pallas 1973) belonging to Tvillingvatnet, Storvatnet and Kolhamna, three lakes located in North Spitsbergen (Svalbard), we propose an integrated approach for the analysis of (i) nutrient and organic matter inputs in lakes; (ii) the role of catchment hydro-geomorphology in determining inter-lake differences in the isotopic composition of sediments; (iii) effects of diverse nutrient inputs on the isotopic niche of Lepidurus arcticus. Given its high run-off and large catchment, organic deposits in Tvillingvatnet where dominated by terrestrial inputs, whereas inputs were mainly of aquatic origin in Storvatnet, a lowland lake with low potential run-off. In Kolhamna, organic deposits seem to be dominated by inputs from birds, which actually colonise the area. Isotopic signatures were similar between samples within each lake, representing precise tracers for studies on the effect of climate change on biogeochemical cycles in lakes. The isotopic niche of L. aricticus reflected differences in sediments between lakes, suggesting a bottom-up effect of hydro-geomorphology characterizing each lake on nutrients assimilated by this species. The presented approach proven to be an effective research pathway for the identification of factors subtending to nutrient and organic matter inputs and transfer

  18. Understanding of the atmospheric methane evolution and change over the last 30 years with focus on the Arctic region

    Science.gov (United States)

    Platt, Stephen; Myhre, Cathrine Lund; Dalsoren, Stig; Hermansen, Ove; Myhre, Gunnar

    2015-04-01

    The methane (CH4) concentration is increasing in the atmosphere, both globally and in the Arctic region since ~2005. The explanation to this is currently not well understood. There are huge reservoirs of CH4 in the Arctic; both methane hydrates in seabed sediments, and organic material in land- and marine-based permafrost which can be partly converted to CH4 after permafrost thaw. Both are vulnerable to destabilization in a warming climate. The Arctic Ocean surface waters may also represent a potentially important source of CH4, which may be sensitive to changes in sea-ice cover. Previous studies show strong atmospheric chemistry feedback to climate warming from Arctic methane emissions. Final results from the GAME project (Causes and effects of Global and Arctic changes in the MEthane budget), and first results from the MOCA project (Methane Emissions from the Arctic OCean to the Atmosphere: Present and Future Climate Effects: http://moca.nilu.no) will be presented. One goal of these studies is to improve the understanding on how emissions in different regions, transport and chemical processes contribute to observed changes in atmospheric methane distribution the last 40 years, with particular focus on the Arctic, including CH4 emissions from the ocean like the East Siberian Arctic Shelf. The work is an integrated study combining new measurements at Zeppelin Observatory, Svalbard, analysis of existing and ongoing methane observations and other relevant species, and Chemical Transport Modelling (CTM). The Oslo CTM3 model is used to calculate distribution and changes over the last 40 years. The study include evaluation of different methane sources and source regions, and chemical processes affecting OH distribution and changes, including changes in anthropogenic and natural emissions from different sources. The Norwegian Research council through the project GAME (Causes and effects of Global and Arctic changes in the MEthane budget), and MOCA (Methane Emissions from

  19. Effect of temperature on sulphate reduction, growth rate and growth yield in five psychrophilic sulphate-reducing bacteria from Arctic sediments

    DEFF Research Database (Denmark)

    Knoblauch, C.; Jørgensen, BB

    1999-01-01

    Five psychrophilic sulphate-reducing bacteria (strains ASv26, LSv21, PSv29, LSv54 and LSv514) isolated from Arctic sediments were examined for their adaptation to permanently low temperatures, All strains grew at -1.8 degrees C, the freezing point of sea water, but their optimum temperature for...... those at T(opt). Short-term incubations of exponentially growing cultures showed that the highest sulphate reduction rates occurred 2-9 degrees C above T(opt). In contrast to growth and sulphate reduction rates, growth yields of strains ASv26, LSv54 and PSv29 were almost constant between -1.8 degrees C...... and T(opt). For strains LSv21 and LSv514, however, growth yields were highest at the lowest temperatures, around 0 degrees C. The results indicate that psychrophilic sulphate-reducing bacteria are specially adapted to permanently low temperatures by high relative growth rates and high growth yields at...

  20. Microplastics in Arctic polar waters: the first reported values of particles in surface and sub-surface samples

    Science.gov (United States)

    Lusher, Amy L.; Tirelli, Valentina; O'Connor, Ian; Officer, Rick

    2015-10-01

    Plastic, as a form of marine litter, is found in varying quantities and sizes around the globe from surface waters to deep-sea sediments. Identifying patterns of microplastic distribution will benefit an understanding of the scale of their potential effect on the environment and organisms. As sea ice extent is reducing in the Arctic, heightened shipping and fishing activity may increase marine pollution in the area. Microplastics may enter the region following ocean transport and local input, although baseline contamination measurements are still required. Here we present the first study of microplastics in Arctic waters, south and southwest of Svalbard, Norway. Microplastics were found in surface (top 16 cm) and sub-surface (6 m depth) samples using two independent techniques. Origins and pathways bringing microplastic to the Arctic remain unclear. Particle composition (95% fibres) suggests they may either result from the breakdown of larger items (transported over large distances by prevailing currents, or derived from local vessel activity), or input in sewage and wastewater from coastal areas. Concurrent observations of high zooplankton abundance suggest a high probability for marine biota to encounter microplastics and a potential for trophic interactions. Further research is required to understand the effects of microplastic-biota interaction within this productive environment.

  1. Persistent organic pollutant levels and the importance of source proximity in Baltic and Svalbard breeding common eiders.

    Science.gov (United States)

    Fenstad, Anette A; Jenssen, Bjørn M; Gabrielsen, Kristin M; Öst, Markus; Jaatinen, Kim; Bustnes, Jan O; Hanssen, Sveinn A; Moe, Børge; Herzke, Dorte; Krøkje, Åse

    2016-06-01

    The distance to sources and the long-range transport potential of persistent organic pollutants (POPs) are important in understanding the impact of anthropogenic pollution on natural seabird populations. The present study documented blood concentrations of POPs in the Baltic Sea (Tvärminne, Finland) population of common eiders (Somateria mollissima) in 2009 and in 2011 and compared the concentrations with the presumably less exposed Arctic population in Svalbard (Kongsfjorden, Norway). The Baltic population had 26, 10, and 5 times greater concentrations of hexachlorocyclohexane, polychlorinated biphenyls, and p,p'-dichlorodiphenyldichloroethylene than the Svalbard population. Unexpectedly, concentrations of chlordanes were higher in Svalbard eiders, whereas concentrations of hexachlorobenzenes (HCBs) did not differ between the 2 populations. Although the similar HCB levels may partly be explained by the high transport potential of HCBs, unknown factors may have been more important than distance to sources and long-range transport potential for the chlordanes. One plausible explanation may be that the fasting-related redistribution of POPs from fat to blood was greater throughout the incubation in Arctic eiders, causing them to have higher blood levels of these POPs at the end of incubation. The blood concentrations of POPs in Baltic eiders were higher than documented in any other eider population and were comparable to levels in seabirds feeding at higher trophic positions in the food chain. Environ Toxicol Chem 2016;35:1526-1533. © 2015 SETAC. PMID:26553455

  2. Sea ice dynamics influence halogen deposition to Svalbard

    Directory of Open Access Journals (Sweden)

    A. Spolaor

    2013-10-01

    Full Text Available Sea ice is an important parameter in the climate system and its changes impact upon the polar albedo and atmospheric and oceanic circulation. Iodine (I and bromine (Br have been measured in a shallow firn core drilled at the summit of the Holtedahlfonna glacier (Northwest Spitsbergen, Svalbard. Changing I concentrations can be linked to the March–May maximum sea ice extension. Bromine enrichment, indexed to the Br / Na sea water mass ratio, appears to be influenced by changes in the seasonal sea ice area. I is emitted from marine biota and so the retreat of March–May sea ice coincides with enlargement of the open-ocean surface which enhances marine primary production and consequent I emission. The observed Br enrichment could be explained by greater Br emissions during the Br explosions that have been observed to occur mainly above first year sea ice during the early springtime. In this work we present the first comparison between halogens in surface snow and Arctic sea ice extension. Although further investigation is required to characterize potential depositional and post-depositional processes, these preliminary findings suggest that I and Br can be linked to variability in the spring maximum sea ice extension and seasonal sea ice surface area.

  3. Sea ice dynamics influence halogen deposition to Svalbard

    Directory of Open Access Journals (Sweden)

    A. Spolaor

    2013-03-01

    Full Text Available Sea ice is an important parameter in the climate system and its changes impact upon the polar albedo and the atmospheric and oceanic circulation. Iodine (I and bromine (Br have been measured in a shallow ice core drilled at the summit of the Holtedahlfonna glacier (Northwest Spitsbergen, Svalbard. Changing I concentrations can be linked to the spring maximum sea ice extension. Bromine enrichment, indexed to the Br/Na sea water mass ratio, appears to be influenced by changes in the seasonal sea ice area. I is emitted from marine biota and so the retreat of spring sea ice coincides with enlargement of the open ocean surface which enhances marine primary production and consequent I emission. The observed Br enrichment can be explained by greater Br emissions during the Br explosion that have been observed to occur above first year sea ice during the early springtime. In this work we present the first comparison between halogens in surface snow and Arctic sea ice extension. Although further investigation is required to characterize potential depositional and post-depositional processes, these preliminary findings suggest that I and Br can be linked to variability in the spring maximum sea ice extension and seasonal sea ice surface area.

  4. Long-term temperature trends and variability on Spitsbergen: the extended Svalbard Airport temperature series, 1898–2012

    Directory of Open Access Journals (Sweden)

    Øyvind Nordli

    2014-01-01

    Full Text Available One of the few long instrumental records available for the Arctic is the Svalbard Airport composite series that hitherto began in 1911, with observations made on Spitsbergen, the largest island in the Svalbard Archipelago. This record has now been extended to 1898 with the inclusion of observations made by hunting and scientific expeditions. Temperature has been observed almost continuously in Svalbard since 1898, although at different sites. It has therefore been possible to create one composite series for Svalbard Airport covering the period 1898–2012, and this valuable new record is presented here. The series reveals large temperature variability on Spitsbergen, with the early 20th century warming as one striking feature: an abrupt change from the cold 1910s to the local maxima of the 1930s and 1950s. With the inclusion of the new data it is possible to show that the 1910s were colder than the years at the start of the series. From the 1960s, temperatures have increased, so the present temperature level is significantly higher than at any earlier period in the instrumental history. For the entire period, and for all seasons, there are positive, statistically significant trends. Regarding the annual mean, the total trend is 2.6°C/century, whereas the largest trend is in spring, at 3.9°C/century. In Europe, it is the Svalbard Archipelago that has experienced the greatest temperature increase during the latest three decades. The composite series may be downloaded from the home page of the Norwegian Meteorological Institute and should be used with reference to the present article.

  5. Polycyclic aromatic and aliphatic hydrocarbons in Chukchi Sea biota and sediments and their toxicological response in the Arctic cod, Boreogadus saida

    Science.gov (United States)

    Harvey, H. Rodger; Taylor, Karen A.; Pie, Hannah V.; Mitchelmore, Carys L.

    2014-04-01

    As part of the Chukchi Sea Offshore Monitoring in Drilling Area-Chemical and Benthos (COMIDA CAB) project, we determined the distribution and concentrations of aliphatic n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments (0-1 cm) among 52 sites across the Chukchi Sea and in muscle tissues of the benthic Northern whelk, Neptunea heros, collected opportunistically. In addition, downcore profiles of contaminants were determined at three targeted sites to establish historic patterns. Baseline responses of PAH exposure and its potential toxicological effects were examined in the common Arctic cod, Boreogadus saida, through measures of cytochrome P4501A/ ethoxyresorufin O-deethylase (CYP1A/EROD), glutathione-S-transferase (GST), and Cu/Zn superoxide dismutase (SOD) activity in liver tissue. The total concentration of PAHs in surface sediments throughout the study area, including parent and alkyl-homologs, were very low (<1600 ng g-1 dry wt) except for a single station, where values were 2-20-fold greater than at other baseline sites (2956 ng g-1 dry wt). Alkyl-substituted PAHs were the dominant form in all surface (54-93%) and subsurface sediments (50-81% of the total), with a general decrease in total PAH concentrations observed downcore. In biota, larger Neptunea showed lower total concentrations of PAHs in foot muscles (4.5-10.7 ng g-1 wet wt) compared to smaller animals; yet aliphatic n-alkane (C19-C33) concentrations (0.655-5.20 μg g-1 wet wt) increased in larger organisms with distributions dominated by long-chain (C23-C33) hydrocarbons. In B. saida, CYP1A1, GST, and SOD enzyme levels were comparable to baseline levels previously reported in other pristine systems. Of the three assays, only SOD had a significant correlation between gene expression and enzyme activity.

  6. Interdisciplinary cooperation on impacts of climate change in the Arctic

    Science.gov (United States)

    Wardell, Lois; Chen, Linling; Strey, Sara

    2012-09-01

    Impact of Climate Change on Resources, Maritime Transport and Geopolitics in the Arctic and the Svalbard Area; Svalbard, Norway, 21-28 August 2011 Drastic changes in the Arctic climate directly relate to resource and transport development and complex geopolitical challenges in the Arctic. To encourage future interdisciplinary cooperation among political, social, and climate scientists, 30 early-career researchers from varied backgrounds—including climate change, resources, polar maritime transport, and geopolitics—assembled in Svalbard, Norway. Ola Johannessen, president of the Norwegian Scientific Academy of Polar Research, led this diverse group to highlight the importance of collaboration across disciplines for broadening the terms in which assessments are defined, thus collapsing distinctions between the physical and the human Arctic. He also highlighted the feasibility of conducting effective assessment exercises within short time frames. The group was also mentored by Willy Østreng, author of Science Without Boundaries: Interdisciplinarity in Research, Society, and Politics, who aided participants in understanding the process of interdisciplinary collaboration rather than creating an assemblage of discrete findings.

  7. Structure and changing dynamics of a polythermal valley glacier on a centennial timescale: Midre Lovenbreen, Svalbard

    DEFF Research Database (Denmark)

    Hambrey, M. J.; Murray, T.; Glasser, N. F.;

    2005-01-01

    structural glaciology, polythermal glacier, Svalbard, ground-penetrating radar, numerical modeling......structural glaciology, polythermal glacier, Svalbard, ground-penetrating radar, numerical modeling...

  8. Digestion of energy and nutrients in Svalbard reindeer

    OpenAIRE

    Hans Staaland; Øritsland, Nils A.; Robert G. White

    1988-01-01

    Feeding trials with 5 male Svalbard reindeer, Rangifer tarandus platyrhynchus Vrolik were conducted at the Man and the Biosphere (MAB) Research Station in Adventdalen, Svalbard. Five different diets were used, 1: commercial reindeer food, (RF-71), 2: a mixture of locally harvested grasses and sedges (mainly Dupontia pelligera and Eriphorum scheusczeri), 3: a pure moss (Pleurozium scheberi) diet, 4: a lichen diet using the dominant Svalbard species Cetraria delisei, and 5: a mixed diet of RF-7...

  9. Climate and environmental changes during the last 2000 years on Barentsøya and Edgeøya (E-Svalbard).

    Science.gov (United States)

    Hoek, Wim; Woelders, Lineke; Akkerman, Keechy; van Hoof, Tom; Moller Just, Rikke; Wagner-Cremer, Friederike

    2016-04-01

    The Svalbard archipelago is positioned at the northern limb of the Atlantic Gulf Stream and, therefore, highly sensitive to climate changes related to changes in ocean circulation. At present, a strong climate gradient from SW-NE Svalbard illustrates the Atlantic influence. While from Spitsbergen (W-Svalbard) several palaeoclimate records are available, while palaeoclimate records from Barentsøya and Edgeøya (E-Svalbard) are lacking. During the 2015 SEES expedition (http://www.sees.nl/) the first lake sediment records from Barentsøya and Edgeøya (E Svalbard) have been collected. The lakes, formed in isolation basins on dolorite plateaus, were selected based on their elevation. Based on published isostatic rebound values, the lakes became disconnected from the sea around 3000 years ago. Since then the lakes recorded biological production changes which are clearly reflected in the lithology of the cores. The presence of abundant plant macro fossils including Salix polaris leaf remains allows for plant palaeophysiological palaeoclimate estimates, which together with pollen and diatom analysis provides a high detail palaeoenvironmental reconstruction for the last 2000 years. Age assessment of the sediments is based on Pb210 and AMS C14 dating on botanical macrofossils, while we also have indications for the presence of Icelandic tephra.

  10. Microbial community structure in lake and wetland sediments from a high Arctic polar desert revealed by targeted transcriptomics.

    Directory of Open Access Journals (Sweden)

    Magdalena K Stoeva

    Full Text Available While microbial communities play a key role in the geochemical cycling of nutrients and contaminants in anaerobic freshwater sediments, their structure and activity in polar desert ecosystems are still poorly understood, both across heterogeneous freshwater environments such as lakes and wetlands, and across sediment depths. To address this question, we performed targeted environmental transcriptomics analyses and characterized microbial diversity across three depths from sediment cores collected in a lake and a wetland, located on Cornwallis Island, NU, Canada. Microbial communities were characterized based on 16S rRNA and two functional gene transcripts: mcrA, involved in archaeal methane cycling and glnA, a bacterial housekeeping gene implicated in nitrogen metabolism. We show that methane cycling and overall bacterial metabolic activity are the highest at the surface of lake sediments but deeper within wetland sediments. Bacterial communities are highly diverse and structured as a function of both environment and depth, being more diverse in the wetland and near the surface. Archaea are mostly methanogens, structured by environment and more diverse in the wetland. McrA transcript analyses show that active methane cycling in the lake and wetland corresponds to distinct communities with a higher potential for methane cycling in the wetland. Methanosarcina spp., Methanosaeta spp. and a group of uncultured Archaea are the dominant methanogens in the wetland while Methanoregula spp. predominate in the lake.

  11. Petrophysical characterization of the lacustrine sediment succession drilled in Lake El'gygytgyn, Far East Russian Arctic

    OpenAIRE

    Gebhardt, A. C.; A. Francke; J. Kück; Sauerbrey, M.; F. Niessen; Wennrich, V.; M. Melles

    2013-01-01

    Seismic profiles of Far East Russian Lake El'gygytgyn which was formed by a meteorite impact some 3.6 million years ago show a stratified sediment succession that can be separated into Subunits Ia and Ib at approximately 167 m below lake floor (= ∼ 3.17 Ma). The former is well-stratified, while the latter is acoustically more massive. The sediments are intercalated with frequent mass movement deposits mainly in the proximal parts, while the distal part is almost free of such dep...

  12. Petrophysical characterization of the lacustrine sediment succession drilled in Lake El’gygytgyn, Far East Russian Arctic

    OpenAIRE

    Gebhardt, A. C.; A. Francke; J. Kück; Sauerbrey, M.; F. Niessen; Wennrich, V.; M. Melles

    2013-01-01

    Seismic profiles of Far East Russian Lake El'gygytgyn, formed by a meteorite impact some 3.6 million years ago, show a stratified sediment succession that can be separated into subunits Ia and Ib at approximately 167 m below lake floor (=~3.17 Ma). The upper (Ia) is well-stratified, while the lower is acoustically more massive and discontinuous. The sediments are intercalated with frequent mass movement deposits mainly in the proximal areas, while the distal region is almost free of such depo...

  13. Conflict and order in Svalbard waters

    OpenAIRE

    Pedersen, Torbjørn

    2008-01-01

    This dissertation examines processes that induce conflict and order in the maritime areas adjacent to the Svalbard archipelago, where Norway’s sovereign rights as coastal state are contested. The first process is the ambiguous causal interplay of international politics and international law: After decades of debate, the parties to it remain reluctant to involve disinterested international third parties to settle their legal differences. Despite the legal character of the dispute, it ...

  14. Spatial and temporal variability in the responses of Arctic terrestrial ecosystems to environmental change

    OpenAIRE

    Callaghan, Terry V.; Press, Malcolm C.; Lee, John A.; Robinson, David L.; Anderson, Clive W.

    1999-01-01

    This paper compares the responses of two contrasting Arctic ecosystems to climate change simulations: a polar semi-desert (in Svalbard) and a dwarf shrub heath (at Abisko, northern Sweden). These ecosystems are located close to the northern-and southernmost extremes of the Arctic region, respectively. Inmacts of simulated climatic changes were determined through factorial perturbation experiments, where growing season temperature, nutrient availability and water supply were manipulated. The r...

  15. Biomonitoring polluted sediments in Arctic regions - possibilities and challenges using benthic foraminifera. Case studies from northern Norway

    Science.gov (United States)

    Skirbekk, Kari; Dijkstra, Noortje; Junttila, Juho; Sternal, Beata; Pedersen, Kristine Bondo; Forwick, Matthias; Carroll, JoLynn

    2016-04-01

    Biomonitoring pollution in marine environments using benthic foraminifera assemblages have proven to be a valid method for many regions. Two important reasons for their suitability are their sensitivity to changes in the environment and their rapid response time due to short life cycles. In addition, they are preserved in the sedimentary record, allowing for baseline studies of conditions prior to introduction of contaminants. Species of benthic foraminifera that appear to tolerate polluted sediments are referred to as opportunistic species. This notion is in general used for species able to dominate environments that are too stressful for most species. The high latitude setting of the northern Norwegian coastal zone experience high seasonality and, hence, largely changing conditions throughout a year: variations in water mass domination, freshwater influence, temperature and current velocity. It is possible that an environment like this is inhibited by a higher amount of opportunistic species generally thriving under high stress conditions. This might make the use of benthic foraminifera for biomonitoring more challenging, as the faunal compositions may be a result of a complex set of processes. Consequently, large datasets are necessary in order to make reliable conclusions, which in time may be used as generalized guidelines for biomonitoring in this geographical area. Here, we present preliminary results of benthic foraminiferal assemblages from two sites in Finnmark, northern Norway, which have been exposed to pollution. The main site is Repparfjorden, where the inner parts of the fjord were used as a submarine waste deposal site for mine tailings from a local copper mine during the 1970´s. Results from four marine sediment cores (10-20 cm long) containing sediments classified to be in moderate to very bad state (according to Norwegian sediment quality criteria) are presented. The contamination is seen in intervals of elevated copper content dated to the 1970

  16. Bioaccumulation of radiocaesium in Arctic seals.

    Science.gov (United States)

    Carroll, Jolynn; Wolkers, Hans; Andersen, Magnus; Rissanen, Kristina

    2002-12-01

    Seals are high trophic level feeders that bioaccumulate many contaminants to a greater degree than most lower trophic level organisms. Their trophic status in the marine food web and wide-spread distribution make seals useful sentinels of arctic environmental change. The purpose of this investigation is to document the levels and bioaccumulation potential of radiocaesium in high latitude seal species for which data have not previously been available. The study was carried out on harp, ringed, and bearded seals caught north of the island archipelago of Svalbard (82 degrees N) in 1999. The results are then compared with previous studies in order to elucidate factors responsible for bioaccumulation in Arctic seals. Concentrations of 137Cs were determined in muscle, liver and kidney samples from a total of 10 juvenile and one adult seal. The mean concentration in muscle samples for all animals was 0.23 +/- 0.045 Bq/kg f.w. 137Cs concentrations in both liver and kidney samples were near detection limits (approximately 0.2 Bq/kg f.w.). The results are consistent with previous studies indicating low levels of radiocaesium in Arctic seals in response to a long term trend of decreasing levels of 137Cs in the Barents Sea region. Bioconcentration factors (BCFs) estimated for seals from NE Svalbard are low, ranging from 34 to 130. Comparing these values with reported BCFs for Greenland seals from other sectors of the European Arctic, we suggest that the combination of physiological and ecological factors on radiocaesium bioaccumulation is comparable among different Arctic seal populations. The application of this work to Arctic monitoring and assessment programs is discussed. PMID:12523541

  17. Bioaccumulation of radiocaesium in Arctic seals

    International Nuclear Information System (INIS)

    Seals are high trophic level feeders that bioaccumulate many contaminants to a greater degree than most lower trophic level organisms. Their trophic status in the marine food web and wide-spread distribution make seals useful sentinels of arctic environmental change. The purpose of this investigation is to document the levels and bioaccumulation potential of radiocaesium in high latitude seal species for which data have not previously been available. The study was carried out on harp, ringed, and bearded seals caught north of the island archipelago of Svalbard (82 deg. N) in 1999. The results are then compared with previous studies in order to elucidate factors responsible for bioaccumulation in Arctic seals. Concentrations of 137Cs were determined in muscle, liver and kidney samples from a total of 10 juvenile and one adult seal. The mean concentration in muscle samples for all animals was 0.23±0.045 Bq/kg f.w. 137Cs concentrations in both liver and kidney samples were near detection limits (∼0.2 Bq/kg f.w.). The results are consistent with previous studies indicating low levels of radiocaesium in Arctic seals in response to a long term trend of decreasing levels of 137Cs in the Barents Sea region. Bioconcentration factors (BCFs) estimated for seals from NE Svalbard are low, ranging from 34 to 130. Comparing these values with reported BCFs for Greenland seals from other sectors of the European Arctic, we suggest that the combination of physiological and ecological factors on radiocaesium bioaccumulation is comparable among different Arctic seal populations. The application of this work to Arctic monitoring and assessment programs is discussed

  18. Bioaccumulation of radiocaesium in Arctic seals

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, JoLynn; Wolkers, Hans; Andersen, Magnus; Rissanen, Kristina

    2002-12-01

    Seals are high trophic level feeders that bioaccumulate many contaminants to a greater degree than most lower trophic level organisms. Their trophic status in the marine food web and wide-spread distribution make seals useful sentinels of arctic environmental change. The purpose of this investigation is to document the levels and bioaccumulation potential of radiocaesium in high latitude seal species for which data have not previously been available. The study was carried out on harp, ringed, and bearded seals caught north of the island archipelago of Svalbard (82 deg. N) in 1999. The results are then compared with previous studies in order to elucidate factors responsible for bioaccumulation in Arctic seals. Concentrations of {sup 137}Cs were determined in muscle, liver and kidney samples from a total of 10 juvenile and one adult seal. The mean concentration in muscle samples for all animals was 0.23{+-}0.045 Bq/kg f.w. {sup 137}Cs concentrations in both liver and kidney samples were near detection limits ({approx}0.2 Bq/kg f.w.). The results are consistent with previous studies indicating low levels of radiocaesium in Arctic seals in response to a long term trend of decreasing levels of {sup 137}Cs in the Barents Sea region. Bioconcentration factors (BCFs) estimated for seals from NE Svalbard are low, ranging from 34 to 130. Comparing these values with reported BCFs for Greenland seals from other sectors of the European Arctic, we suggest that the combination of physiological and ecological factors on radiocaesium bioaccumulation is comparable among different Arctic seal populations. The application of this work to Arctic monitoring and assessment programs is discussed.

  19. Petrophysical characterization of the lacustrine sediment succession drilled in Lake El'gygytgyn, Far East Russian Arctic

    Directory of Open Access Journals (Sweden)

    A. C. Gebhardt

    2013-01-01

    Full Text Available Seismic profiles of Far East Russian Lake El'gygytgyn which was formed by a meteorite impact some 3.6 million years ago show a stratified sediment succession that can be separated into Subunits Ia and Ib at approximately 167 m below lake floor (= ∼ 3.17 Ma. The former is well-stratified, while the latter is acoustically more massive. The sediments are intercalated with frequent mass movement deposits mainly in the proximal parts, while the distal part is almost free of such deposits at least in the upper part. In spring 2009, a long core drilled in the lake center within the framework of the International Continental Scientific Drilling Program (ICDP penetrated the entire lacustrine sediment succession down to ~ 320 m below lake floor and about 200 m further into the meteorite-impact related bedrock. Downhole logging data down to 390 m below lake floor show that the bedrock and the lacustrine part of the core differ largely in their petrophysical characteristics. The contact between the bedrock and the lacustrine sediments is not abrupt, but rather transitional with a mixture of impact-altered bedrock clasts in a lacustrine matrix with varying percentages. Physical and chemical proxies measured on the cores can be used to divide the lacustrine part into five different clusters. These can be plotted in a redox-condition vs. input type diagram with total organic carbon content and magnetic susceptibility values indicating anoxic or oxic conditions and with the Si/Ti ratio representing more clastic or more biogenic input. Plotting the clusters in this diagram allows identifying clusters that represent glacial phases (Cluster I, super interglacials (Cluster II, and interglacial phases (Clusters III and IV.

  20. Petrophysical characterization of the lacustrine sediment succession drilled in Lake El'gygytgyn, Far East Russian Arctic

    Directory of Open Access Journals (Sweden)

    A. C. Gebhardt

    2013-08-01

    Full Text Available Seismic profiles of Far East Russian Lake El'gygytgyn, formed by a meteorite impact some 3.6 million years ago, show a stratified sediment succession that can be separated into subunits Ia and Ib at approximately 167 m below lake floor (=~3.17 Ma. The upper (Ia is well-stratified, while the lower is acoustically more massive and discontinuous. The sediments are intercalated with frequent mass movement deposits mainly in the proximal areas, while the distal region is almost free of such deposits at least in the upper part. In spring 2009, a long core drilled in the lake center within the framework of the International Continental Scientific Drilling Program (ICDP penetrated the entire lacustrine sediment succession down to ~320 m below lake floor and about 200 m farther into the meteorite-impact-related bedrock. Downhole logging data down to 390 m below lake floor show that the bedrock and the lacustrine part differ significantly in their petrophysical characteristics. The contact between the bedrock and the lacustrine sediments is not abrupt, but rather transitional with a variable mixture of impact-altered bedrock clasts in a lacustrine matrix. Physical and chemical proxies measured on the cores can be used to divide the lacustrine part into five different statistical clusters. These can be plotted in a redox-condition vs. input-type diagram, with total organic carbon content and magnetic susceptibility values indicating anoxic or oxic conditions and with the Si / Ti ratio representing more clastic or more biogenic input. Plotting the clusters in this diagram allows identifying clusters that represent glacial phases (cluster I, super interglacials (cluster II, and interglacial phases (clusters III and IV.

  1. Temperature induced decoupling of enzymatic hydrolysis and carbon remineralization in long-term incubations of Arctic and temperate sediments

    OpenAIRE

    Robador, Alberto; Brüchert, Volker; Steen, Andrew; Arnosti, Carol

    2010-01-01

    Udgivelsesdato: 2010 Extracellular enzymatic hydrolysis of high-molecular weight organic matter is the initial step in sedimentary organic carbon degradation and is often regarded as the rate-limiting step. Temperature effects on enzyme activities may therefore exert an indirect control on carbon mineralization. We explored the temperature sensitivity of enzymatic hydrolysis and its connection to subsequent steps in anoxic organic carbon degradation in long-term incubations of sediments fr...

  2. On the issue of the Precambrian basement of the Arctic shelf

    Science.gov (United States)

    Vernikovsky, Valery A.; Korago, Evgeny A.; Proskurnin, Vasily F.; Sobolev, Nikolay N.

    2015-04-01

    Many researchers of the geological structures of the Russian Arctic concluded that the basements of the terranes composing the Arctic shelf and continental slopes have a Precambrian age. It is assumed that these terranes are actually fragments of the ancient Arctida paleocontinent [Zonenshain, Natapov, 1987] that broke up as a result of rifting and its separate plates and terranes either were overlain by continental margins sediments or included in the fold belts in the periphery of the ocean. In the western part of the Russian Arctic, a Grenvillian and Mesoproterozoic basement was demonstrated for Svalbard, Novaya Zemlya and Taimyr Peninsula, and at least a Neoproterozoic basement was established for structures in the basement of Severnaya Zemlya archipelago. In the eastern part of the Russian Arctic, such proofs were almost nonexistent. In recent years, new information was obtained concerning the continental nature and Precambrian age of the basement crust of the New Siberian Islands and De Long archipelagos as well as probably the Mendeleev Ridge. For the New Siberian Islands and De Long archipelagos, a whole series of geochronological evidence was obtained in addition to geological data (horizontally bedding Early Paleozoic passive continental margin sediments (Cambrian, Ordovician) at Bennett Island). In magmatic and tuffaceous-sedimentary rocks of Henrietta and Zhokhov islands we discovered zircons that had formed from magmatic crystallization in the Late Neoproterozoic. New U-Pb data for zircons from rocks of these islands do not contradict isotopic dating obtained earlier by other methods - Ar/Ar and Sm/Nd in different laboratories. Considering different closure temperatures for isotopic systems, these new results complement each other. On the islands of the eastern sector of the Russian Arctic, a Neoproterozoic complex of rocks is most certainly established in the basement of the mesozoides of Vrangel Island. Here were discovered metamorphosed volcanics

  3. Multi-channel seismic reflection measurements in the Eurasian Basin, Arctic Ocean, from U.S. ice station Fram-IV

    Science.gov (United States)

    Kristoffersen, Yngve; Husebye, Eystein S.

    1985-04-01

    We present the first multi-channel seismic reflection data ever collected from the Eurasian Basin of the Arctic Ocean. The 200 km data set was acquired by a 20 channel sonobuoy array deployed at U.S. ice drift station FRAM-IV and operated for 34 days about 370 km north of Svalbard in April-May 1982. Cross array drift and ice floe rotation which may constitute the most serious obstacle to the advantage of multi-channel data acquisition did only occur to a minor degree during the experiment and render most of the data set suitable for processing using common mid-point binning. A 0.7-1.4 s (two-way traveltime) thick sedimentary section has been deposited over oceanic crust of mid-Oligocene age below the Barents Abyssal Plain. In the deepest part, sediments are infilling topographic lows which indicate predominantly turbidite deposition. Erosional truncations are only locally present in the central part of the section. Conformable bedforms deposited over gentle basement highs indicate a relatively stable bottom current regime since mid-Oligocene time. Thus the establishment of a deep water connection between the Arctic Ocean and lower latitude water masses appear to have had only minor effect on Eurasian Basin bottom current circulation. Extensive submarine slide scars on the north slope of Yermak Plateau show that mass waste have been a sediment source to the Barents Abyssal Plain.

  4. Persistent organic pollutants in biota samples collected during the Ymer-80 expedition to the Arctic

    Directory of Open Access Journals (Sweden)

    Henrik Kylin

    2015-10-01

    Full Text Available During the 1980 expedition to the Arctic with the icebreaker Ymer, a number of vertebrate species were sampled for determination of persistent organic pollutants. Samples of Arctic char (Salvelinus alpinus, n=34, glaucous gull (Larus hyperboreus, n=8, common eider (Somateria mollissima, n=10, Brünnich's guillemot (Uria lomvia, n=9, ringed seal (Pusa hispida, n=2 and polar bear (Ursus maritimus, n=2 were collected. With the exception of Brünnich's guillemot, there was a marked contamination difference of birds from western as compared to eastern/northern Svalbard. Samples in the west contained a larger number of polychlorinated biphenyl (PCB congeners and also polychlorinated terphenyls, indicating local sources. Brünnich's guillemots had similar pollutant concentrations in the west and east/north; possibly younger birds were sampled in the west. In Arctic char, pollutant profiles from lake Linnévatn (n=5, the lake closest to the main economic activities in Svalbard, were similar to profiles in Arctic char from the Shetland Islands (n=5, but differed from lakes to the north and east in Svalbard (n=30. Arctic char samples had higher concentrations of hexachlorocyclohexanes (HCHs than the marine species of birds and mammals, possibly due to accumulation via snowmelt. Compared to the Baltic Sea, comparable species collected in Svalbard had lower concentrations of PCB and dichlorodiphenyltrichloroethane (DDT, but similar concentrations indicating long-range transport of hexachlorobenzene, HCHs and cyclodiene pesticides. In samples collected in Svalbard in 1971, the concentrations of PCB and DDT in Brünnich's guillemot (n=7, glaucous gull (n=2 and polar bear (n=2 were similar to the concentrations found in 1980.

  5. Search for tick-borne pathogens in the Svalbard Archipelago and Jan Mayen

    Directory of Open Access Journals (Sweden)

    Jana Elsterová

    2015-10-01

    Full Text Available The tick species Ixodes uriae, parasitizing seabirds in the Arctic, may transmit many pathogens including various arboviruses, Borrelia spirochetes and Babesia apicomplexans. These pathogens may pose an important additional stress to seabirds, which are already stressed by environmental changes such as pollutants and decreased food availability. Here, we present the results of the first screening for arboviruses of the genera Flavivirus, Alphavirus, Orthobunyavirus, Phlebovirus and Orbivirus, as well as Borrelia spirochetes and Babesia apicomplexans from Svalbard and Jan Mayen. Using polymerase chain reaction technology with genus-specific primers, we tested 89 ticks collected on Jan Mayen, Bjørnøya and Spitsbergen between 2008 and 2012. We did not detect any of the screened tick-borne pathogens. Nevertheless, these pathogens may be introduced to Svalbard and Jan Mayen by migratory birds in the near future. The increasing numbers of ticks appearing in the studied areas make this introduction even more likely. Such an introduction would have serious impact on seabird ecology as well as on human public health. Therefore, continuous careful surveillance and monitoring of possible tick-borne pathogen introductions is important.

  6. Warming of the West Spitsbergen Current and sea ice north of Svalbard

    Directory of Open Access Journals (Sweden)

    Jan Piechura

    2009-06-01

    Full Text Available This research was supported by a grant from the Fifth European Union Frame-work Programme project ASOF-N, contract EVK2-CT-200200139, the Sixth Frame-work Programme DAMOCLES, contract 018509GOCE, and grants from the Polish Ministry of Science and Higher Education, decisions 61/N-IPY/2007/0 and 175/IPY/2007/01.AbstractAccording to the results of recent research, besides the atmospheric circulation, it is heat transport to the Arctic Ocean (AO by ocean currents, the West Spitsbergen Current (WSC in particular, that is playing a significant role in the process of Arctic warming. Data collected by the Institute of Oceanology, Polish Academy of Sciences (IO PAS, in the Norwegian and Greenland Seas, and Fram Strait during the last 20 years reveal considerable changes in the amount of heat transported by the WSC into the Arctic Ocean. An increase in Atlantic Water (AW temperature and the intensification of heat transport were observed in 2004-06; after this period, both parameters decreased. The aim of this study was to find out whether the fluctuations in heat input by the WSC have influenced the sea-ice distribution around Svalbard. In fact they do, but oceanic heat transport should nonetheless be regarded as just one of many processes influencing sea-ice behaviour.

  7. Water-ice actions on the coal quay at Kapp Amsterdam in Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Loset, Sveinung [Centre for Sustainanble Arctic Marine and Coastal Technology, Norwegian University of Science and Technology, Trondheim (Norway); Marchenko, Aleksey; Shestov, Aleksey [The University Centre in Svalbard, Longyerbyen (Norway); Sigitov, Anton [AGIP KCO (Kazakhstan)

    2011-07-01

    In Arctic conditions, the presence of ice in harbours is challenging since ice can form on the sea surface inside and outside the quay. Deformations can occur with the combined ice and water action on structural elements of the quay. This paper investigated the water-ice action on the coal quay at Kapp Amsterdam in Svalbard. Physical mechanisms of ice actions observed on the sheet piling were analyzed using field and laboratory studies. Field work below the quay have were performed in March-April 2009 and 2010. Measurements of water pressure, temperature at the bottom, water depths in different areas and seabed topography were conducted. Vertical displacements of several points on the ice surface were measured. Laboratory experiments were also carried out, including calculation of the long term and short term ice permeability of saline ice. The results showed that the effect of localization can increase the ice permeability in conditions of lower temperatures.

  8. The Drabo corymbosae-Papaveretea dahliani − a new vegetation class of the High Arctic polar deserts

    Directory of Open Access Journals (Sweden)

    Daniëls Fred J. A.

    2016-06-01

    Full Text Available A new class and a new order (Drabo corymbosae-Papaveretea dahliani and Saxifrago oppositifoliae-Papaveretalia dahliani have been described, and the Papaverion dahliani validated. This is vegetation of zonal habitats in lowlands of the High Arctic subzone A (or Arctic herb, cushion forb or polar desert subzone and of ecologically equivalent sites at high altitudes on the mountain plateaus of the High Arctic. The new class spans three continents – North America (Canadian Arctic Archipelago and Greenland, Europe (parts of Svalbard and Franz Josef Land, and Asia, including northern regions of Chelyuskin Peninsula (Taymir Peninsula, Severnaya Zemlya Archipelago and De Longa Islands.

  9. Gas hydrate distribution and hydrocarbon maturation north of the Knipovich Ridge, western Svalbard margin

    Science.gov (United States)

    Dumke, Ines; Burwicz, Ewa B.; Berndt, Christian; Klaeschen, Dirk; Feseker, Tomas; Geissler, Wolfram H.; Sarkar, Sudipta

    2016-03-01

    A bottom-simulating reflector (BSR) occurs west of Svalbard in water depths exceeding 600 m, indicating that gas hydrate occurrence in marine sediments is more widespread in this region than anywhere else on the eastern North Atlantic margin. Regional BSR mapping shows the presence of hydrate and free gas in several areas, with the largest area located north of the Knipovich Ridge, a slow spreading ridge segment of the Mid Atlantic Ridge system. Here heat flow is high (up to 330 mW m-2), increasing toward the ridge axis. The coinciding maxima in across-margin BSR width and heat flow suggest that the Knipovich Ridge influenced methane generation in this area. This is supported by recent finds of thermogenic methane at cold seeps north of the ridge termination. To evaluate the source rock potential on the western Svalbard margin, we applied 1-D petroleum system modeling at three sites. The modeling shows that temperature and burial conditions near the ridge were sufficient to produce hydrocarbons. The bulk petroleum mass produced since the Eocene is at least 5 kt and could be as high as ~0.2 Mt. Most likely, source rocks are Miocene organic-rich sediments and a potential Eocene source rock that may exist in the area if early rifting created sufficiently deep depocenters. Thermogenic methane production could thus explain the more widespread presence of gas hydrates north of the Knipovich Ridge. The presence of microbial methane on the upper continental slope and shelf indicates that the origin of methane on the Svalbard margin varies spatially.

  10. Tracing the Origins of Organic Matter in the Ice of Svalbard, Norway

    Science.gov (United States)

    Vidonish, J. E.; Bowden, R.; Benning, L. G.; Eigenbrode, J. L.; Fogel, M. L.

    2011-12-01

    Determining the origin of organic matter (OM) in Arctic ice is of key importance in understanding the nature and origin of life in both modern and ancient ice. In turn, knowledge of this OM is important for studying biosignatures of ice, necessary for the search for life on Mars. In a study of samples from Svalbard, Norway, both stable isotope analysis and the presence of a unique UV-absorbing pigment (scytonemin) serve as a means of tracing potential sources of organic matter to glacial ice. Possible sources for glacial OM include the following: 1) aeolian sources including black carbon or local soils, creating "dirty snow", 2) plant sources from surrounding areas including higher plants, lichens, and mosses, 3) microbial sources from on the ice itself , i.e., snow algae and cryoconites, and 4) microbial biofilms and endoliths from nearby habitats.. The UV-sunscreen pigment scytonemin is prevalent in many of the sources, particularly snow algae, cryoconites, lichens and microbial biofilms, as determined by spectrophotometry and ultra-performance LCMS analysis. These same methods also revealed the presence of scytonemin in various ice cores and surface runoff samples, suggesting that these plant and microbial sources are indeed tied to the introduction of OM to the ice of Svalbard. Supporting pigment signature tracing, stable isotope analysis of 13C and 15N shows a clear trend confirming the origin of OM from regional organic matter, as both ice cores and runoff have an isotopic signature comparable to Svalbard plants, snow algae, cryconites, and lichen. These two lines of evidence conclude in tandem that the OM found in Svalbard's glaciers have an origin in the surrounding ecosystem. This finding suggests that traces of life can both be transported and preserved in ice for extended periods of time. This has especial meaning in the pursuit of biosignatures on Mars, as well as the study of paleoclimate on Earth. Future studies can focus on further tracing of

  11. Histochemical and enzymatic differences in skeletal muscle from Svalbard reindeer during the summer and winter

    Directory of Open Access Journals (Sweden)

    K.-H. Kiessling

    1986-06-01

    Full Text Available Enzyme activities and fibre properties in four muscles from Svalbard reindeer, collected during the summer, have been compared with corresponding muscles during the winter. In two muscles, gluteobiceps and semimembranosus, oxidative capacity is higher in winter than in summer; in the other two muscles, semitendinosus and longissimus dorsi, there is no difference with time of the year. The capacity to oxidize fatty acids is low in winter compared with summer, especially in semitendinosus and longissimus. These changes are similar in both sexes. Histochemical studies of the three main fibre types, I (BetaR, HA (°cR and IIB (aW, from the four muscles show that in male reindeers the muscle fibres are narrower at the end of the winter season than during the summer. The decrease of muscle tissue amounts to about one third of the total volume (33%, of which I accounts for 5%, IIA for 2% and IIB for 26%. The results indicate that the Svalbard reindeer use lean tissue in general, and IIB fibres in particular, in order to survive the hostile arctic winter period at Svalbard.Histokemiska och enzymatiska skillnader i skelettmuskel från Svalbardren mellan sommar och vinter.Abstract in Swedish / Sammandrag: Enzymaktiviteter och fiberegenskaper i fyra av Svalbardrenens muskler, insamlade under sommaren, har jåmforts med motsvarande muskler insamlade under vintern. I två muskler, gluteobiceps och semimembranosus, år oxidativa kapaciteten hogre under vintern an under sommaren; i de andra två musklerna, semitendinosus och longissimus dorsi, foreligger ingen skillnad i detta avseende. Kapaciteten att oxidera fettsyror år låg under vintern jåmfort med sommaren, speciellt i semitendinosus och longissimus. Inga konsskillnader foreligger i dessa avseenden. Histokemiska studier av de tre huvudtyperna av muskelfibrer, fiR (I, ocR (IIA och (IIB, från de fyra musklerna visar att hos handjuren år fibrerna tunnare vid slutet av vintersåsongen jåmfort med

  12. Benthic algal vegetation in Isfjorden, Svalbard

    Directory of Open Access Journals (Sweden)

    Stein Fredriksen

    2015-08-01

    Full Text Available Benthic algal vegetation was investigated at 10 sites in Isfjorden, Svalbard. Five sites were visited during summer 2010 and five during summer 2012. Both the littoral and sublittoral vegetation were sampled, the littoral by hand-picking and use of a throwable rake and the sublittoral using a triangular dredge. A total of 88 different taxa were registered, comprising 17 Chlorophyta, 40 Ochrophyta, 30 Rhodophyta and the Xantophyceae Vaucheria sp. The green algae Ulvaria splendens (Ruprecht Vinogradova was recorded in Svalbard for the first time. Most of the sites consisted of hard bottom substrate, but one site, Kapp Wijk, consisted of loose-lying calcareous red algae (rhodoliths and had species not recorded elsewhere. The sublittoral at the other sites was dominated by kelp. Molecular analysis confirmed the presence of the red alga Ceramium virgatum and a dwarf form of the brown alga Fucus vesiculosus. This study provides a baseline for future studies investigating changes in the vegetation due to environmental changes.

  13. Amsterdamøya: a key site for the post-glacial of Svalbard

    Science.gov (United States)

    Bakke, Jostein; Balascio, Nicholas; van der Bilt, Willem; D`Andrea, William; Bradley, Raymond; Gjerde, Marthe; Hormes, Anne; Olafsdottir, Sædis; Røthe, Torgeir; Vasskog, Kristian; De Wet, Greg; Werner, Johannes

    2016-04-01

    No other place on Earth is changing as fast as the Arctic in terms of climate. On average this region is warming twice as fast as the global average with a seasonal bias towards winter. A major retreat in sea ice extent accompanied by an even more massive thinning represents one of the most robust trends in the Arctic. This trend is anticipated to continue in the decades to come and, according to some models, will leave the Arctic Ocean open during summer some time between 2050-2100. Unabated reduction in the spring-snow cover represents another significant trend. The current warming is also expressed in the massive melting of the Greenland ice sheet as well as local glaciers and ice caps in the Arctic, which causes increased freshwater influx to the Arctic Ocean and adjacent seas. Climate modeling and scenarios are improving and becoming of growing importance, but without a firmer understanding of natural climate variability over longer timescale it is still hard to evaluate and best read the output from these models. In the SHIFTS project we have done an unparalleled effort to overcome this quandary, providing necessary empirical data on past climate which is critical for assessing past changes in atmospheric circulation patterns controlling Arctic hydroclimate. Our study site is located at the northwestern corner of Svalbard on the Island of Amsterdamøya, a site sensitive to changes in both oceanic and atmospheric forcing, at tail of the westward moving branch of the North Atlantic current. Here we have cored several lakes with the goal of providing quantitative data on temperature, hydrology and winter precipitation for the Holocene. Our approach has been to combine reconstruction of glaciers with lipid biomarkers and hydrogen isotopes with the goal of unravel the underlying signature of past climate in the Arctic. Chronological control is secured by radiocarbon dates on macrofossils combined with measurement of paleomagnetic secular variations. Here we

  14. Long-term changes in pigmentation of arctic Daphnia provide potential for reconstructing aquatic UV exposure

    Science.gov (United States)

    Nevalainen, Liisa; Rantala, Marttiina V.; Luoto, Tomi P.; Ojala, Antti E. K.; Rautio, Milla

    2016-07-01

    Despite the biologically damaging impacts of solar ultraviolet radiation (UV) in nature, little is known about its natural variability, forcing mechanisms, and long-term effects on ecosystems and organisms. Arctic zooplankton, for example the aquatic keystone genus Daphnia (Crustacea, Cladocera) responds to biologically damaging UV by utilizing photoprotective strategies, including pigmentation. We examined the preservation and content of UV-screening pigments in fossil Daphnia remains (ephippia) in two arctic lake sediment cores from Cornwallis Island (Lake R1), Canada, and Spitsbergen (Lake Fugledammen), Svalbard. The aims were to document changes in the degree of UV-protective pigmentation throughout the past centuries, elucidate the adaptive responses of zooplankton to long-term variations in UV exposure, and estimate the potential of fossil zooplankton pigments in reconstructing aquatic UV regimes. The spectroscopic absorbance measurements of fossil Daphnia ephippia under UV (280-400 nm) and visible light (400-700 nm) spectral ranges indicated that melanin (absorbance maxima at UV wavebands 280-350 nm) and carotenoids (absorbance maxima at 400-450 nm) pigments were preserved in the ephippia in both sediment cores. Downcore measurements of the most important UV-protective pigment melanin (absorbance measured at 305 and 340 nm) showed marked long-term variations in the degree of melanisation. These variations likely represented long-term trends in aquatic UV exposure and were positively related with solar radiation intensity. The corresponding trends in melanisation and solar activity were disrupted at the turn of the 20th century in R1, but remained as strong in Fugledammen. The reversed trends in the R1 core were simultaneous with a significant aquatic community reorganization taking place in the lake, suggesting that recent environmental changes, likely related to climate warming had a local effect on pigmentation strategies. This time horizon is also

  15. Arctic Study of Tropospheric Aerosol and Radiation (ASTAR) 2000: Arctic haze case study

    OpenAIRE

    T. Yamanouchi; R. Treffeisen; A. Herber; Shiobara, M.; S. Yamagata; Hara, K.; Sato, K; Yabuki, M.; Tomikawa, Y.; Rinke, A.; R. Neuber; Schumachter, R.; M. Kriews; J. Ström; O. Schrems

    2005-01-01

    The ASTAR 2000 (Arctic Study of Tropospheric Aerosol and Radiation) campaign ran from 12 March until 25 April 2000 with extensive flight operations in the vicinity of Svalbard (Norway) from Longyearbyen airport (78.25°N, 15.49°E). It was a joint Japanese (NIPR Tokyo)–German (AWI Bremerhaven/Potsdam) airborne measurement campaign using AWI aircraft POLAR 4 (Dornier 228-101). Simultaneous ground-based measurements were done at the international research site Ny-Ålesund (78.95°N, 11.93°E) in Sva...

  16. Constraints on sea to air emissions from methane clathrates in the vicinity of Svalbard

    Science.gov (United States)

    Pisso, Ignacio; Vadakkepuliyambatta, Sunil; Platt, Stephen Matthew; Eckhardt, Sabine; Allen, Grant; Pitt, Joseph; Silyakova, Anna; Hermansen, Ove; Schmidbauer, Norbert; Mienert, Jurgen; Myhre, Cathrine Lund; Stohl, Andreas

    2016-04-01

    Methane stored in the seabed in the form of clathrates has the potential to be released into the atmosphere due to ongoing ocean warming. The Methane Emissions from Arctic Ocean to Atmosphere (MOCA, http://moca.nilu.no/) proje sct conducted measurement campaigns in the vicinity of Svalbard during the summers of 2014 and 2015 in collaboration with the Centre for Arctic Gas Hydrate, Environment and Climate (CAGE, https://cage.uit.no/) and the MAMM (https://arcticmethane.wordpress.com) project . The extensive set of measurements includes air (BAe 146) and ship (RV Helmer Hansen) borne methane concentrations, complemented with the nearby monitoring site at Zeppelin mountain. In order to assess the atmospheric impact of emissions from seabed methane hydrates, we characterised the local and long range atmospheric transport during the aircraft campaign and different scenarios for the emission sources. We present a range of upper bounds for the CH4 emissions during the campaign period as well as the methodologies used to obtain them. The methodologies include a box model, Lagrangian transport and elementary inverse modelling. We emphasise the analysis of the aircraft data. We discuss in detail the different methodologies used for determining the upper flux bounds as well as its uncertainties and limitations. The additional information provided by the ship and station observations will be briefly mentioned.

  17. Arctic Submarine Slope Stability

    Science.gov (United States)

    Winkelmann, D.; Geissler, W.

    2010-12-01

    Submarine landsliding represents aside submarine earthquakes major natural hazard to coastal and sea-floor infrastructure as well as to coastal communities due to their ability to generate large-scale tsunamis with their socio-economic consequences. The investigation of submarine landslides, their conditions and trigger mechanisms, recurrence rates and potential impact remains an important task for the evaluation of risks in coastal management and offshore industrial activities. In the light of a changing globe with warming oceans and rising sea-level accompanied by increasing human population along coasts and enhanced near- and offshore activities, slope stability issues gain more importance than ever before. The Arctic exhibits the most rapid and drastic changes and is predicted to change even faster. Aside rising air temperatures, enhanced inflow of less cooled Atlantic water into the Arctic Ocean reduces sea-ice cover and warms the surroundings. Slope stability is challenged considering large areas of permafrost and hydrates. The Hinlopen/Yermak Megaslide (HYM) north of Svalbard is the first and so far only reported large-scale submarine landslide in the Arctic Ocean. The HYM exhibits the highest headwalls that have been found on siliciclastic margins. With more than 10.000 square kilometer areal extent and app. 2.400 cubic kilometer of involved sedimentary material, it is one of the largest exposed submarine slides worldwide. Geometry and age put this slide in a special position in discussing submarine slope stability on glaciated continental margins. The HYM occurred 30 ka ago, when the global sea-level dropped by app. 50 m within less than one millennium due to rapid onset of global glaciation. It probably caused a tsunami with circum-Arctic impact and wave heights exceeding 130 meters. The HYM affected the slope stability field in its neighbourhood by removal of support. Post-megaslide slope instability as expressed in creeping and smaller-scaled slides are

  18. Atmospheric methane emissions along the western Svalbard margin

    Science.gov (United States)

    Pohlman, J.; Greinert, J.; Silyakova, A.; Casso, M.; Ruppel, C. D.; Mienert, J.; Lund Myhre, C.; Bunz, S.

    2014-12-01

    Documented warming of intermediate waters by ~1oC over the past 30 years along the western Svalbard margin has been suggested as a driver of climate-change induced dissociation of marine methane hydrate. However, recent evidence suggests methane release from gas hydrate has been occurring for thousands of years near the upper limit of methane hydrate stability and that seasonal changes in bottom water temperature may be more important than longer-term warming of intermediate waters. Nevertheless, this area has been and remains an active area for researching the physical and climate controls of methane release from the seafloor, yet the amount of methane reaching the atmosphere (the ultimate climate driver) in this region is largely unknown. As part of the MOCA project led by the Norwegian Institute for Air Research (NILU), water column and atmospheric marine boundary layer methane data were collected in June 2014 aboard the R/V Helmer Hanssenduring a collaboration among CAGE at University of Tromsӧ, NILU, GEOMAR, and the USGS. The results provide a continuous record of surface methane concentration and carbon isotope data from continental slope sites near temperature-sensitive hydrate-bearing seeps along the shelf-break and upper slope, the deep-water pockmarked gas-venting Vestnesa Ridge and a shallow water seep area within the Forlandet moraine complex at the shelf. Surface water methane and associated data used to calculate sea-air fluxes were obtained with the cavity ring-down spectrometer-based USGS Gas Analysis System (USGS-GAS). Only the shallow seep site (~90 m water depth) had appreciable methane in surface waters. We conducted an exhaustive survey of this site, mapping the full extent of the surface methane plume. To provide three-dimensional constraints, we acquired 65 vertical dissolved methane profiles to delineate the vertical and horizontal extent of the subsurface methane plume. Using these data, we assess how effectively shallow arctic seeps

  19. Arctic Newcomers

    DEFF Research Database (Denmark)

    Tonami, Aki

    2013-01-01

    Interest in the Arctic region and its economic potential in Japan, South Korea and Singapore was slow to develop but is now rapidly growing. All three countries have in recent years accelerated their engagement with Arctic states, laying the institutional frameworks needed to better understand an...

  20. Mass losses from Svalbard land-terminating glaciers by the end of the 21st century under an RCP 8.5 scenario

    Science.gov (United States)

    Möller, Marco; Navarro, Francisco; Martín-Español, Alba

    2016-04-01

    The high Arctic archipelagos are among the most strongly glacierized landscapes on earth apart from the Greenland and Antarctic ice sheets. Svalbard, one of these archipelagos, holds about 36,000 km2 of glaciers and ice caps and is the region that has shown the least negative mass balance of all the high Arctic regions. However, future projections suggest that the archipelago will experience an unprecedented -for the Arctic- glacier recession over the 21st century. We here present a high-resolution modelling study of the future ice-mass evolution of 29 individual land-terminating glaciers on the Svalbard archipelago under an RCP 8.5 climate forcing, a rather pessimistic scenario that unfortunately seems to be becoming realistic. Our model calculates glacier mass balance and area/volume changes using a temperature-index approach in combination with a surface elevation change parameterization. The initial glacier topographies and volumes have been assessed from extensive ground-penetrating radar measurements carried out in recent years. The calculations are performed for the 21st century and are forced by statistically downscaled output of ten different global circulation models representing the RCP scenario 8.5. By a topography-based extrapolation of the simulation results to the entire archipelago we show that a complete loss of most of Svalbard's land-terminating glaciers and even a deglaciation of certain subregions of the archipelago might occur by the end of the 21st century. 98% of the land-terminating glaciers will have retreated to less than one tenth of their initial extent by 2100, resulting in a loss of 7392±2481 km2 of ice coverage.

  1. Regime shifts in the northern North Atlantic during the past 6,000 years: A record of seabird population size and precipitation isotopes on Bjørnøya, Svalbard

    Science.gov (United States)

    D'Andrea, W. J.; Hormes, A.; Bakke, J.; Nicolaisen, L.

    2015-12-01

    The northeastern North Atlantic Ocean, and the Norwegian and Greenland Seas are subject to large hydrographic changes. These variations can influence oceanic heat transport to the Arctic, meridional overturning circulation, and atmospheric circulation patterns and thereby impact global climate patterns. Marine records suggest that numerous large-scale changes in the hydrography of the northern North Atlantic took place during the middle to late Holocene. Here, we report a record of nitrogen and hydrogen isotope measurements from a lake sediment core from Bjørnøya, Svalbard (74.38°N, 19.02°E) that documents major regime shifts in the climate of the northern North Atlantic during the past 6,000 years. Bjørnøya is the nesting ground for one of the largest seabird populations in the North Atlantic. As top predators in the marine ecosystem, seabirds (and their guano) are enriched in 15N; during spring and summer months they deliver this isotopically enriched nitrogen to their nesting area. We developed a record of seabird population changes on Bjørnøya based on the bulk nitrogen isotope composition of sediments in a core collected from lake Ellasjøen. The record reveals multiple multicentennial scale changes in δ15N values (varying between ~8-12‰) that track past changes in the size of seabird populations. From the same sediment core, we also developed a record of δD of precipitation, by measuring δD values of sedimentary n-alkanes. Past intervals with the largest inferred bird populations correspond with the most enriched δD of precipitation, which we interpret to represent a more Atlantic climate. Periods with reduced seabird populations correspond with intervals having more negative δD of precipitation and representing a more Arctic climate. Together, the nitrogen and hydrogen isotope records signify regime shifts in the oceanography, marine ecosystem, and atmospheric circulation of the northern North Atlantic that are related to variations in the

  2. An Interglacial Polar Bear and an Early Weichselian Glaciation at Poolepynten, Western Svalbard

    Science.gov (United States)

    Ingolfsson, O.; Alexanderson, H.

    2012-12-01

    Recent discovery of a subfossil polar bear (Ursus maritimus) jawbone in the Poolepynten coastal cliff sequence, western Svalbard (Ingolfsson & Wiig, 2009), and its implications for the natural history of the polar bear (Lindqvist et al. 2010; Miller et al. 2012), motivated an effort to better constrain the environmental history and age envelope of the Poolepynten sediment sequence, particularly the lithostratigraphy of the coastal cliffs with emphasis on re-dating the sequence using the optically stimulated luminescence (OSL) dating technique. We report a revised lithostratigraphy and nine new OSL ages. It is concluded that the Poolepynten sequence holds evidence of four regional glaciation events, recorded in the strata as erosional unconformities and/or glacial deposits followed by shallow-marine deposition signifying transgressions and subsequent glacio-isostatic rebound and regression. Our OSL ages refine previous age determinations (14C and IRSL) and support the interpretation that the subfossil polar bear jawbone is of last interglacial (Eemian) age (Alexanderson et al. in press). References: Alexanderson, H., Ingolfsson, O., Murray, A.S. & Dudek, J. in press. An Interglacial Polar Bear and an Early Weichselian Glaciation at Poolepynten, Western Svalbard. Boreas 00, 000-000. Ingolfsson, O. & Wiig, O. 2009. Late Pleistocene fossil find in Svalbard: the oldest remains of a polar bear (Ursus maritimus Phipps, 1744) ever discovered. Polar Research 28, 455-466. Lindqvist, C., Schuster, S. C., Sun, Y., Talbot, S. L., Qi, J., Ratan, A., Tomsho, L. P., Kasson, L., Zeyl, E., Aars, J., Miller, W., Ingólfsson, Ó., Bachmann, L. & Wiig, Ø. 2010. Complete mitochondrial genome of a Pleistocene jawbone unveils the origin of polar bear. Proceedings of the National Academy of Sciences 107, 5053-5057. Miller, W., Schuster, S. C., Welch, A. J., Ratan, A., Bedoya-Reina, O. C., Zhao, F., Kim, H. L., Burhans, R.C., Drautz, D.I., Wittekindt, N.E., Tomsho, L.P., Ibarra-Laclette, E

  3. Plio-Pleistocene evolution of water mass exchange and erosional input at the Atlantic-Arctic gateway

    Science.gov (United States)

    Teschner, Claudia; Frank, Martin; Haley, Brian A.; Knies, Jochen

    2016-05-01

    Water mass exchange between the Arctic Ocean and the Norwegian-Greenland Seas has played an important role for the Atlantic thermohaline circulation and Northern Hemisphere climate. We reconstruct past water mass mixing and erosional inputs from the radiogenic isotope compositions of neodymium (Nd), lead (Pb), and strontium (Sr) at Ocean Drilling Program site 911 (leg 151) from 906 m water depth on Yermak Plateau in the Fram Strait over the past 5.2 Myr. The isotopic compositions of past bottom waters were extracted from authigenic oxyhydroxide coatings of the bulk sediments. Neodymium isotope signatures obtained from surface sediments agree well with present-day deepwater ɛNd signature of -11.0 ± 0.2. Prior to 2.7 Ma the Nd and Pb isotope compositions of the bottom waters only show small variations indicative of a consistent influence of Atlantic waters. Since the major intensification of the Northern Hemisphere Glaciation at 2.7 Ma the seawater Nd isotope composition has varied more pronouncedly due to changes in weathering inputs related to the waxing and waning of the ice sheets on Svalbard, the Barents Sea, and the Eurasian shelf, due to changes in water mass exchange and due to the increasing supply of ice-rafted debris (IRD) originating from the Arctic Ocean. The seawater Pb isotope record also exhibits a higher short-term variability after 2.7 Ma, but there is also a trend toward more radiogenic values, which reflects a combination of changes in input sources and enhanced incongruent weathering inputs of Pb released from freshly eroded old continental rocks.

  4. Observations of enhanced thinning in the upper reaches of Svalbard glaciers

    Directory of Open Access Journals (Sweden)

    T. D. James

    2012-11-01

    Full Text Available Changes in the volume and extent of land ice of the Svalbard archipelago have been the subject of considerable research since their sensitivity to changes in climate was first noted. However, the measurement of these changes is often necessarily based on point or profile measurements which may not be representative if extrapolated to a whole catchment or region. Combining high-resolution elevation data from contemporary laser-altimetry surveys and archived aerial photography makes it possible to measure historical changes across a glacier's surface without the need for extrapolation. Here we present a high spatial resolution time-series for six Arctic glaciers in the Svalbard archipelago spanning 1961 to 2005. We find high variability in thinning rates between sites with prevalent elevation changes at all sites averaging −0.59 ± 0.04 m a−1 between 1961–2005. Prior to 1990, ice surface elevation was changing at an average rate of −0.52 ± 0.09 m a−1 which decreased to −0.76 ± 0.10 m a−1 after 1990. Setting the elevation changes against the glaciers' altitude distribution reveals that significant increases in thinning rates are occurring most notably in the glaciers' upper reaches. We find that these changes are coincident with a decrease in winter precipitation at the Longyearbyen meteorological station and could reflect a decrease in albedo or dynamic response to lower accumulation. Further work is required to understand fully the causes of this increase in thinning rates in the glaciers' upper reaches. If on-going and occurring elsewhere in the archipelago, these changes will have a significant effect on the region's future mass balance. Our results highlight the importance of understanding the climatological context of geodetic mass balance measurements and demonstrate the difficulty of using index glaciers to represent regional changes in areas of strong climatological gradients.

  5. Arctic Watch

    Science.gov (United States)

    Orcutt, John; Baggeroer, Arthur; Mikhalevsky, Peter; Munk, Walter; Sagen, Hanne; Vernon, Frank; Worcester, Peter

    2015-04-01

    The dramatic reduction of sea ice in the Arctic Ocean will increase human activities in the coming years. This will be driven by increased demand for energy and the marine resources of an Arctic Ocean more accessible to ships. Oil and gas exploration, fisheries, mineral extraction, marine transportation, research and development, tourism and search and rescue will increase the pressure on the vulnerable Arctic environment. Synoptic in-situ year-round observational technologies are needed to monitor and forecast changes in the Arctic atmosphere-ice-ocean system at daily, seasonal, annual and decadal scales to inform and enable sustainable development and enforcement of international Arctic agreements and treaties, while protecting this critical environment. This paper will discuss multipurpose acoustic networks, including subsea cable components, in the Arctic. These networks provide communication, power, underwater and under-ice navigation, passive monitoring of ambient sound (ice, seismic, biologic and anthropogenic), and acoustic remote sensing (tomography and thermometry), supporting and complementing data collection from platforms, moorings and autonomous vehicles. This paper supports the development and implementation of regional to basin-wide acoustic networks as an integral component of a multidisciplinary, in situ Arctic Ocean Observatory.

  6. Chlorinated hydrocarbon contaminants in arctic marine mammals.

    Science.gov (United States)

    Norstrom, R J; Muir, D C

    1994-09-16

    . Lawrence and ringed seal in the Baltic Sea, indicate that overall contamination of the Arctic marine ecosystem is 10-50 times less than the most highly contaminated areas in the northern hemisphere temperate latitude marine environment. Geographic distribution of residue levels in polar bears indicates a gradual increase from Alaska east to Svalbard, except PCB levels are significantly higher in eastern Greenland and Svalbard. Information on temporal trends is somewhat contradictory.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7973601

  7. Pan-Arctic observations in GRENE Arctic Climate Change Research Project and its successor

    Science.gov (United States)

    Yamanouchi, Takashi

    2016-04-01

    We started a Japanese initiative - "Arctic Climate Change Research Project" - within the framework of the Green Network of Excellence (GRENE) Program, funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT), in 2011. This Project targeted understanding and forecasting "Rapid Change of the Arctic Climate System and its Global Influences." Four strategic research targets are set by the Ministry: 1. Understanding the mechanism of warming amplification in the Arctic; 2. Understanding the Arctic climate system for global climate and future change; 3. Evaluation of the impacts of Arctic change on the weather and climate in Japan, marine ecosystems and fisheries; 4. Projection of sea ice distribution and Arctic sea routes. Through a network of universities and institutions in Japan, this 5-year Project involves more than 300 scientists from 39 institutions and universities. The National Institute of Polar Research (NIPR) works as the core institute and The Japan Agency for Marine- Earth Science and Technology (JAMSTEC) joins as the supporting institute. There are 7 bottom up research themes approved: the atmosphere, terrestrial ecosystems, cryosphere, greenhouse gases, marine ecology and fisheries, sea ice and Arctic sea routes and climate modeling, among 22 applications. The Project will realize multi-disciplinal study of the Arctic region and connect to the projection of future Arctic and global climatic change by modeling. The project has been running since the beginning of 2011 and in those 5 years pan-Arctic observations have been carried out in many locations, such as Svalbard, Russian Siberia, Alaska, Canada, Greenland and the Arctic Ocean. In particular, 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard, and intensive atmospheric observations were carried out in 2014 and 2015. In addition, the Arctic Ocean cruises by R/V "Mirai" (belonging to JAMSTEC) and other icebreakers belonging to other

  8. Surface radiation during the total solar eclipse over Ny-Ålesund, Svalbard, on 20 March 2015

    Science.gov (United States)

    Maturilli, Marion; Ritter, Christoph

    2016-04-01

    On 20 March 2015, a total solar eclipse occurred over Ny-Ålesund (78.9° N, 11.9° E), Svalbard, in the high Arctic. It was the first time that the surface radiation components during the totality of a solar eclipse were measured by a Baseline Surface Radiation Network (BSRN) station. With the Ny-Ålesund long-term radiation data set as background (available at http://dx.doi.org/10.1594/PANGAEA.150000" target="_blank">doi:10.1594/PANGAEA.150000), we present here the peculiarities of the radiation components and basic meteorology observed during the eclipse event. The supplementary data set contains the basic BSRN radiation and surface meteorological data in 1 min resolution for March 2015, and is available at http://dx.doi.org/10.1594/PANGAEA.854326" target="_blank">doi:10.1594/PANGAEA.854326. The eclipse radiation data will be a useful auxiliary data set for further studies on micrometeorological surface-atmosphere exchange processes in the Svalbard environment, and may serve as a test case for radiative transfer studies.

  9. Isotopic and Geochemical Investigation of Two Distinct Mars Analog Environments Using Evolved Gas Techniques in Svalbard, Norway

    Science.gov (United States)

    Stern, Jennifer Claire; Mcadam, Amy Catherine; Ten Kate, Inge L.; Bish, David L.; Blake, David F.; Morris, Richard V.; Bowden, Roxane; Fogel, Marilyn L.; Glamoclija, Mihaela; Mahaffy, Paul R.; Steele, Andrew; Amundsen, Hans E. F.

    2013-01-01

    The 2010 Arctic Mars Analog Svalbard Expedition (AMASE) investigated two distinct geologic settings on Svalbard, using methodologies and techniques to be deployed on Mars Science Laboratory (MSL). AMASErelated research comprises both analyses conducted during the expedition and further analyses of collected samples using laboratory facilities at a variety of institutions. The Sample Analysis at Mars (SAM) instrument suite on MSL includes pyrolysis ovens, a gas-processing manifold, a quadrupole mass spectrometer (QMS), several gas chromatography columns, and a Tunable Laser Spectrometer (TLS). An integral part of SAM development is the deployment of SAM-like instrumentation in the field. During AMASE 2010, two parts of SAM participated as stand-alone instruments. A Hiden Evolved Gas Analysis- Mass Spectrometer (EGA-QMS) system represented the EGA-QMS component of SAM, and a Picarro Cavity Ring Down Spectrometer (EGA-CRDS), represented the EGA-TLS component of SAM. A field analog of CheMin, the XRD/XRF on MSL, was also deployed as part of this field campaign. Carbon isotopic measurements of CO2 evolved during thermal decomposition of carbonates were used together with EGA-QMS geochemical data, mineral composition information and contextual observations made during sample collection to distinguish carbonates formation associated with chemosynthetic activity at a fossil methane seep from abiotic processes forming carbonates associated with subglacial basaltic eruptions. Carbon and oxygen isotopes of the basalt-hosted carbonates suggest cryogenic carbonate formation, though more research is necessary to clarify the history of these rocks.

  10. Energy and mass exchange between ocean and atmosphere in the area of winter polynya to the north of Svalbard

    Science.gov (United States)

    Ivanov, Boris; Wesman, Anna; Sviashchennikov, Pavel; Pavlov, Alexey

    2015-04-01

    The warm inflow of the West Spitsbergen Current keeps waters ice-free in winter to the north of Svalbard, an area also called the Whalers Bay. Here we present results of the winter expedition in the Arctic Ocean to the north of Svalbard on board a research vessel «Helmer Hanssen» in January 2012. The characteristics of the turbulent energy and mass exchange are calculated using an algorithm, which is based on semi-empirical theory of "Monin-Obukhov", adapted to the conditions of marine meteorological observations. The results are compared with the data obtained in this area in February 1986 on board Russian research icebreaker "Otto Schmidt". The features of energy-mass exchange are explained by synoptic and ice conditions in the study area. Intense heat and mass exchange in the area leads to enhanced convective mixing and, thus, upwelling of nutrients to surface waters that can contribute to higher biological activity in the area throughout the food web.

  11. Tourism and Arctic Observation Systems: exploring the relationships

    Directory of Open Access Journals (Sweden)

    Suzanne de la Barre

    2016-03-01

    Full Text Available The Arctic is affected by global environmental change and also by diverse interests from many economic sectors and industries. Over the last decade, various actors have attempted to explore the options for setting up integrated and comprehensive trans-boundary systems for monitoring and observing these impacts. These Arctic Observation Systems (AOS contribute to the planning, implementation, monitoring and evaluation of environmental change and responsible social and economic development in the Arctic. The aim of this article is to identify the two-way relationship between AOS and tourism. On the one hand, tourism activities account for diverse changes across a broad spectrum of impact fields. On the other hand, due to its multiple and diverse agents and far-reaching activities, tourism is also well-positioned to collect observational data and participate as an actor in monitoring activities. To accomplish our goals, we provide an inventory of tourism-embedded issues and concerns of interest to AOS from a range of destinations in the circumpolar Arctic region, including Alaska, Arctic Canada, Iceland, Svalbard, the mainland European Arctic and Russia. The article also draws comparisons with the situation in Antarctica. On the basis of a collective analysis provided by members of the International Polar Tourism Research Network from across the polar regions, we conclude that the potential role for tourism in the development and implementation of AOS is significant and has been overlooked.

  12. Experimentally determined temperature thresholds for Arctic plankton community metabolism

    Directory of Open Access Journals (Sweden)

    J. M. Holding

    2013-01-01

    Full Text Available Climate warming is especially severe in the Arctic, where the average temperature is increasing 0.4 °C per decade, two to three times higher than the global average rate. Furthermore, the Arctic has lost more than half of its summer ice extent since 1980 and predictions suggest that the Arctic will be ice free in the summer as early as 2050, which could increase the rate of warming. Predictions based on the metabolic theory of ecology assume that temperature increase will enhance metabolic rates and thus both the rate of primary production and respiration will increase. However, these predictions do not consider the specific metabolic balance of the communities. We tested, experimentally, the response of Arctic plankton communities to seawater temperature spanning from 1 °C to 10 °C. Two types of communities were tested, open-ocean Arctic communities from water collected in the Barents Sea and Atlantic influenced fjord communities from water collected in the Svalbard fjord system. Metabolic rates did indeed increase as suggested by metabolic theory, however these results suggest an experimental temperature threshold of 5 °C, beyond which the metabolism of plankton communities shifts from autotrophic to heterotrophic. This threshold is also validated by field measurements across a range of temperatures which suggested a temperature 5.4 °C beyond which Arctic plankton communities switch to heterotrophy. Barents Sea communities showed a much clearer threshold response to temperature manipulations than fjord communities.

  13. Tidal currents in the western Svalbard Fjords

    Directory of Open Access Journals (Sweden)

    Zygmunt Kowalik

    2015-10-01

    Full Text Available The paper is focusing on the tides and on the strong tidal current generated in the western fjords of Svalbard. Numerical model is chosen as a tool to study the barotropic tides. Model results are compared against measured sea level and drifters. Numerical modeling and observation of tides point that the tidal amplitude does not change strongly in these fjords but the tidal currents are enhanced in several locations, namely at the entrance to the Dickson Fjord, in the narrow passages in proximity to Svea, and in the central part of Van Keulenfjorden. As the strongest currents have been found at the passages at Akseløya Island we have focused our research on this location. The narrow northern channel (Akselsundet at Akseløya is the main waterway to Svea coal mines. Tidal currents computed and observed at the northern tip of Akseløya Island can reach amplitude from 2 to 3 m s−1. Observation of the deployed drifters and calculation of the seeded particles in the passage at Akseløya depicted a complicated pattern of eddies. The jet-like currents and eddies are quite different at the ebb and flood tide phases. As the Akseløya Island orientation relative to the shore is different for the flood and ebb waters the flow through Akselsundet is differently constrained by this geometry. The observations show that the oscillating tidal motion causes large excursions of the water particle. The drifters released in the passage during flood ended up trapped in the eddy on the eastern side of the island.

  14. The Arctic

    International Nuclear Information System (INIS)

    Global climate change in the Arctic is a growing concern. Research has already documented pronounced changes, and models predict that increases in temperature from anthropogenic influences could be considerably higher than the global average. The impacts of climate change on Arctic ecosystems are complex and difficult to predict because of the many interactions within ecosystem, and between many concurrently changing environmental variables. Despite the global consequences of change in the Arctic climate the monitoring of basic abiotic as well as biotic parameters are not adequate to assess the impact of global climate change. The uneven geographical location of present monitoring stations in the Arctic limits the ability to understand the climate system. The impact of previous variations and potential future changes to ecosystems is not well understood and need to be addressed. At this point, there is no consensus of scientific opinion on how much of the current changes that are due to anthropogenic influences or to natural variation. Regardless of the cause, there is a need to investigate and assess current observations and their effects to the Arctic. In this chapter examples from both terrestrial and marine ecosystems from ongoing monitoring and research projects are given. (LN)

  15. Walrus Odobenus rosmarus research in Svalbard, Norway, 2000-2010

    Directory of Open Access Journals (Sweden)

    Christian Lydersen

    2013-08-01

    Full Text Available Herein we report results from studies on walruses in Svalbard conducted in 2000-2010. Data from newly developed satellite relay data loggers (SRDLs revealed seasonal differences in habitat use of adult male walruses. During winter, they moved into areas of >90% ice concentration, traveling as far as 600 km from ice-free water. Breeding areas deep into the pack ice were identified based on timing of the occupancy and diving behaviour. When the breeding season was over, walruses with SRDLs that were still transmitting locations returned to the coast, showing high site fidelity to the previous year’s summering area. Haul-out data from the SRDLs provided correction factors for an aerial survey of walruses that covered all known haul-out sites within the Svalbard Archipelago. This survey estimated 2,629 (95 % CI; 2,318 – 2,998 walruses to be in Svalbard during August 2006. Blubber biopsies from adult male walruses analyzed for fatty acids (FAs showed vertical stratification similar to that observed in many other marine mammals. However, differences between layers were less pronounced, possibly because the thick dermis of walruses provides an insulating shield, affecting the FA composition of the outer blubber. The FA composition of the inner blubber most closely resembled the lipids in Mya truncata and Buccinum spp., which are considered the most important walrus prey in Svalbard. A study investigating the use of skin biopsies for assessing levels of organochlorines (OCs in walruses found a significant relationship between OC levels in skin and blubber. Another contaminant study found a significant decrease in levels of PCBs and DDE in walruses in Svalbard from 1993 to 2002-04. Large inter-individual variation in OC levels was found, although all of the study animals were adult males from roughly the same location. In FA analyses of the inner blubber this variation appeared to be diet-related, with high OC levels having FA compositions in the

  16. The Role of Sea Ice for Vascular Plant Dispersal in the Arctic

    Science.gov (United States)

    Geirsdottir, A.; Alsos, I. G.; Seidenkrantz, M. S.; Bennike, O.; Kirchhefer, A.; Ehrich, D.

    2015-12-01

    Plant species adapted to arctic environments are expected to go extinct at their southern margins due to climate warming whereas they may find suitable habitats on arctic islands if they are able to disperse there. Analyses of species distribution and phylogenetic data indicate both that the frequency of dispersal events is higher in the arctic than in other regions, and that the dispersal routes often follow the routes of sea surface currents. Thus, it has been hypothesised that sea ice has played a central role in Holocene colonisation of arctic islands. Here we compile data on the first Holocene occurrence of species in East Greenland, Iceland, the Faroe Islands, and Svalbard. We then combine these records with interpretations of dispersal routes inferred from genetic data and data on geographical distributions, reconstructions of Holocene sea ice extent, and records of driftwood to evaluate the potential role sea ice has played in past colonisation events.

  17. Winter temperature affects the prevalence of ticks in an Arctic seabird.

    Directory of Open Access Journals (Sweden)

    Sébastien Descamps

    Full Text Available The Arctic is rapidly warming and host-parasite relationships may be modified by such environmental changes. Here, I showed that the average winter temperature in Svalbard, Arctic Norway, explained almost 90% of the average prevalence of ticks in an Arctic seabird, the Brünnich's guillemot Uria lomvia. An increase of 1°C in the average winter temperature at the nesting colony site was associated with a 5% increase in the number of birds infected by these ectoparasites in the subsequent breeding season. Guillemots were generally infested by only a few ticks (≤5 and I found no direct effect of tick presence on their body condition and breeding success. However, the strong effect of average winter temperature described here clearly indicates that tick-seabird relationships in the Arctic may be strongly affected by ongoing climate warming.

  18. Arctic bioremediation

    International Nuclear Information System (INIS)

    Cleanup of oil and diesel spills on gravel pads in the Arctic has typically been accomplished by utilizing a water flushing technique to remove the gross contamination or excavating the spill area and placing the material into a lined pit, or a combination of both. Enhancing the biological degradation of hydrocarbon (bioremediation) by adding nutrients to the spill area has been demonstrated to be an effective cleanup tool in more temperate locations. However, this technique has never been considered for restoration in the Arctic because the process of microbial degradation of hydrocarbon in this area is very slow. The short growing season and apparent lack of nutrients in the gravel pads were thought to be detrimental to using bioremediation to cleanup Arctic oil spills. This paper discusses the potential to utilize bioremediation as an effective method to clean up hydrocarbon spills in the northern latitudes

  19. 白令海和西北冰洋表层沉积物磁化率特征初步研究%Magnetic susceptibility characteristics of surface sediments in Bering Sea and western Arctic Ocean:preliminary results

    Institute of Scientific and Technical Information of China (English)

    汪卫国; 戴霜; 陈莉莉; 吴日升; 余兴光

    2014-01-01

    The mass-dependent magnetic susceptibility (χ)with low and high frequency,anhysteretic susceptibility (χARM )and temperature-dependent susceptibility (k-T )of 61 surface sediment samples obtained from Bering Sea and western Arctic Ocean were measured with an attempt to find the composition,province and transport of mag-netic minerals,which is helpful to accurately decipher the paleo-climate and environmental information recorded by the magnetic parameters in Arctic area.The results show that theχvalues of surface sediments have an evident re-gional difference.Theχvalues are commonly higher in Bering Sea than that in Chukchi Sea,and they are the low-est in the plains and ridges of high western Arctic Ocean.Theχvalues are the highest off the Yukon River estuary and to the south of St.Lawrence Island in Bering Sea shelf,decreasing northward and south-westward.Theχval-ues are relatively higher in the central-eastern Chukchi Sea shelf than that off the Alaskan coast.The χARM share the common variation trends ofχ,however,the frequency-dependent susceptibility changes oppositely to that ofχ. The analysis of k-T shows that the magnetic mineral in surface sediments in Aleutian Basin is maghemite,and off the Yukon River estuary and to the south of St.Lawrence Island is magnetite,and both maghemite and magnetite occur in the western shelf of Bering Sea and central-eastern shelf of Chukchi Sea.The magnetic mineral of surface sediment off the Alaskan coast is pyrite,while in the slope,plains and ridges of high western Arctic Ocean,the magnetic minerals are greigite and pyrite,but the content of greigite is higher in high latitude.The regional distri-bution of magnetic minerals in surface sediments is controlled by the sources of sediments,currents and bottom en-vironments.The maghemite in the shelf of Bering Sea and Chukchi Sea is from the Asian main land,and the mag-netite in eastern Bering Sea shelf is from the watershed of Yukon River.Pyrite off the Alaskan coast

  20. Spatial Trends of Trace-Element Contamination in Recently Deposited Lake Sediment Around the Ni–Cu Smelter at Nikel, Kola Peninsula, Russian Arctic

    OpenAIRE

    Rognerud, Sigurd; Dauvalter, Vladimir A.; Fjeld, Eirik; Skjelkvåle, Brit Lisa; Christensen, Guttorm; Kashulin, Nickolay

    2013-01-01

    A large copper–nickel smelter complex is located at the Kole Penninsula, Russia, close to the Norwegian border. Trace-element concentrations in surface sediments (0–0.5 cm) and pre-industrial sediments from 45 lakes in the region were used to uncover spatial deposition patterns and contamination factor of sediments. Elevated concentrations were found, especially for Ni and Cu, but also for Pb, Co, Hg, As, and Cd. Highest concentrations were found up to 20 km from the smelter, but the concentr...

  1. Arctic bioremediation

    International Nuclear Information System (INIS)

    Cleanup of oil and diesel spills on gravel pads in the Arctic has typically been accomplished by utilizing a water flushing technique to remove the gross contamination or excavating the spill area and placing the material into a lined pit, or a combination of both. This paper discusses the potential to utilize bioremediation as an effective method to clean up hydrocarbon spills in the northern latitudes. Discussed are the results of a laboratory bioremediation study which simulated microbial degradation of hydrocarbon under arctic conditions

  2. Adaptive harvest management for the Svalbard population of pink-footed geese: briefing summary

    Science.gov (United States)

    Johnson, Fred A.

    2013-01-01

    The African-Eurasian Waterbird Agreement (AEWA; http://www.unep-aewa.org/) calls for means to manage populations which cause conflicts with certain human economic activities. The Svalbard population of the pink-footed goose has been selected as the first test case for such an international species management plan to be developed. This document describes progress to date on the development of an adaptive harvest management (AHM) strategy for maintaining pink-footed goose abundance near their target level by providing for sustainable harvasts in Norway and Denmark. This briefing supplements material provided in the Progress Summary distributed to the International Working Group on February 1, 2013. We emphasize that peer review is an essential aspect of the process of developing and implementing an AHM program for pink-footed geese, and we will continue to solicit reviews by the International Working Group and their staff, as well as scientists not engaged in this effort. We wish to make the Working Group aware the the following two manuscripts have been submitted recently to refereed journals and are available upon request from the senior authors: Jensen, G.H., J. Madsen, F.A. Johnson, and M. Tamstorf. Snow conditions as an estimator of the breeding output in high-Arctic pink-footed geese Anser brachyrhynchus. Polar Biology: In review. Johnson, F.A., G.H. Jensen, J. Madsen, and B.K. Williams. Uncertainity, robustness, and the value of information in managing an expanding Arctic goose population. Ecological Modeling: In review. In addition to these manuscripts, the Progress Summary (February 1, 2013), and this Briefing Summary (April 23, 2013) an annual report will be produced in August 2013 and every summer thereafter. Additional manuscripts for journal publication are also anticipated.

  3. Spatial and temporal trends in perfluoroalkyl substances (PFASs) in ringed seals (Pusa hispida) from Svalbard.

    Science.gov (United States)

    Routti, Heli; Gabrielsen, Geir Wing; Herzke, Dorte; Kovacs, Kit M; Lydersen, Christian

    2016-07-01

    This study investigates concentrations of perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates (PFSAs) and perfluoroalkane sulfonamides (FASA) in plasma from ringed seals sampled in the period 1990-2010 (n = 71) in Svalbard, Norway. Perfluorooctane sulfonate was dominant among the perfluoroalkyl substances. PFCAs were dominated by perfluoroundecanoate followed by perfluorononanoate. C4C8 PFCAs and perfluorooctane sulfonamide (FOSA) were detected in ≤42% of the samples. PFSA and PFCA concentrations were higher in seals sampled from Kongsfjorden, a fjord influenced by strong inflows of Atlantic Water compared to seals from fjords dominated by Arctic Water (e.g. Billefjorden). Sex, age and body condition of the seals did not influence PFAS concentrations. Due to the confounding effect of year and sampling area, temporal trends were assessed only in seals sampled from Kongsfjorden (5 years, n = 51). PFHxS and PFOS concentrations did not show significant linear trends during the whole study period, but a decrease was observed since 2004. Concentrations of all of the detected PFCAs (C9C13 PFCAs) increased until 2004 after which they have declined or stabilized. PMID:27089420

  4. Measurements of Atmospheric Aerosol Vertical Distributions above Svalbard, Norway using Unmanned Aerial Systems (UAS)

    Science.gov (United States)

    Bates, T. S.; Johnson, J. E.; Stalin, S.; Telg, H.; Murphy, D. M.; Burkhart, J. F.; Quinn, P.; Storvold, R.

    2015-12-01

    Atmospheric aerosol vertical distributions were measured above Svalbard, Norway in April 2015 to investigate the processes controlling aerosol concentrations and radiative effects. The aerosol payload was flown in a NOAA/PMEL MANTA Unmanned Aerial System (UAS) on 9 flights totaling 19 flight hours. Measurements were made of particle number concentration and aerosol light absorption at three wavelengths, similar to those conducted in April 2011 (Bates et al., Atmos. Meas. Tech., 6, 2115-2120, 2013). A filter sample was collected on each flight for analyses of trace elements. Additional measurements in the aerosol payload in 2015 included aerosol size distributions obtained using a Printed Optical Particle Spectrometer (POPS) and aerosol optical depth obtained using a four wavelength miniature Scanning Aerosol Sun Photometer (miniSASP). The data show most of the column aerosol mass and resulting optical depth in the boundary layer but frequent aerosol layers aloft with high particle number concentration (2000 cm-3) and enhanced aerosol light absorption (1 Mm-1). Transport of these aerosol layers was assessed using FLEXPART particle dispersion models. The data contribute to an assessment of sources of BC to the Arctic and potential climate impacts.

  5. Fossil Find on Svalbard Highlights the Natural History of the Polar Bear (Ursus maritimus)

    Science.gov (United States)

    Ingolfsson, O.; Wiig, O.

    2007-12-01

    During recent fieldwork on Svalbard a well preserved subfossil left ramus of a polar bear (Ursus maritimus) mandible was discovered. A 14C age determination shows that it is older than 45 ka (kilo-years), and an OSL (Optical Stimulated Luminescence) age determination together with the stratigraphic position of the bone suggests that it is of Eemian-Early Weichselian/Wisconsinan age, 150-80 ka old. This puts the find among the oldest fossil remains of a polar bear ever discovered. Osteological study of the mandible suggests that it comes from a fully grown female. The fossil record suggests that polar bears may have developed from brown bears during the early part of the last glacial cycle, some 100 ka ago. The present interglacial might be the first such that the species has to endure. This underlines the potential status of the polar bears as an endangered species if the current warming trend and diminishing of sea ice cover in the Arctic continues.

  6. Metagenomics of the Svalbard reindeer rumen microbiome reveals abundance of polysaccharide utilization loci.

    Directory of Open Access Journals (Sweden)

    Phillip B Pope

    Full Text Available Lignocellulosic biomass remains a largely untapped source of renewable energy predominantly due to its recalcitrance and an incomplete understanding of how this is overcome in nature. We present here a compositional and comparative analysis of metagenomic data pertaining to a natural biomass-converting ecosystem adapted to austere arctic nutritional conditions, namely the rumen microbiome of Svalbard reindeer (Rangifer tarandus platyrhynchus. Community analysis showed that deeply-branched cellulolytic lineages affiliated to the Bacteroidetes and Firmicutes are dominant, whilst sequence binning methods facilitated the assemblage of metagenomic sequence for a dominant and novel Bacteroidales clade (SRM-1. Analysis of unassembled metagenomic sequence as well as metabolic reconstruction of SRM-1 revealed the presence of multiple polysaccharide utilization loci-like systems (PULs as well as members of more than 20 glycoside hydrolase and other carbohydrate-active enzyme families targeting various polysaccharides including cellulose, xylan and pectin. Functional screening of cloned metagenome fragments revealed high cellulolytic activity and an abundance of PULs that are rich in endoglucanases (GH5 but devoid of other common enzymes thought to be involved in cellulose degradation. Combining these results with known and partly re-evaluated metagenomic data strongly indicates that much like the human distal gut, the digestive system of herbivores harbours high numbers of deeply branched and as-yet uncultured members of the Bacteroidetes that depend on PUL-like systems for plant biomass degradation.

  7. Observations of widespread accelerated thinning in the upper reaches of Svalbard glaciers

    Directory of Open Access Journals (Sweden)

    T. D. James

    2012-03-01

    Full Text Available The measured rise in eustatic sea level over the 20th century was dominated by mass loss from the world's mountain glaciers and ice caps, and predictions suggest that these fresh water reservoirs will remain significant into the 21st century. However, estimates of this mass transfer to the ocean are based on a limited number of observations extrapolated to represent not only regional changes but often changes across individual glaciers. Combining high resolution elevation data from contemporary laser-altimetry surveys and archived aerial photography makes it possible to measure historical changes across a glacier's entire surface. Here we present a high spatial resolution time-series for six Arctic glaciers in the Svalbard Archipelago spanning 1961 to 2005. We find increasing thinning rates before and after 1990 with elevation losses occurring most notably in the glaciers' upper reaches. In the absence of a clear meteorological driver, we recommend further investigation into a possible albedo amplification of prevailing meteorological trends to explain these higher elevation changes, which could have important consequences on the region's mass balance due to the sensitivity of its hypsometric distribution. However, the strong influence of decadal-scale variability, while explaining lower rates of mass loss reported in earlier studies, highlights that caution must be exercised when interpreting thinning rates when averaged over long periods.

  8. Hollow rhodoliths increase Svalbard's shelf biodiversity

    Science.gov (United States)

    Teichert, Sebastian

    2014-11-01

    Rhodoliths are coralline red algal assemblages that commonly occur in marine habitats from the tropics to polar latitudes. They form rigid structures of high-magnesium calcite and have a good fossil record. Here I show that rhodoliths are ecosystem engineers in a high Arctic environment that increase local biodiversity by providing habitat. Gouged by boring mussels, originally solid rhodoliths become hollow ecospheres intensely colonised by benthic organisms. In the examined shelf areas, biodiversity in rhodolith-bearing habitats is significantly greater than in habitats without rhodoliths and hollow rhodoliths yield a greater biodiversity than solid ones. This biodiversity, however, is threatened because hollow rhodoliths take a long time to form and are susceptible to global change and anthropogenic impacts such as trawl net fisheries that can destroy hollow rhodoliths. Rhodoliths and other forms of coralline red algae play a key role in a plurality of environments and need improved management and protection plans.

  9. Mesozoic authigenic carbonate deposition in the Arctic: Do glendonites record gas hydrate destabilization during the Jurassic?

    Science.gov (United States)

    Morales, Chloe; Suan, Guillaume; Wierzbowski, Hubert; Rogov, Mikhail; Teichert, Barbara; Kienhuis, Michiel V. M.; Polerecky, Lubos; Middelburg, Jack B. M.; Reichart, Gert-Jan; van de Schootbrugge, Bas

    2015-04-01

    Glendonites are calcite pseudomorphs after ikaite, an unstable hydrated calcium carbonate mineral. Because present-day ikaite occurs predominantly in sub-polar environments and is unstable at warm temperatures, glendonites have been used as an indicator of near-freezing conditions throughout Earth history. Ikaite has also been observed in cold deep-sea environments like the Gulf of Mexico, the Japan Trench, and the Zaire Fan where their formation is possibly governed by other parameters. The description of glendonites in Paleocene-Eocene sediments of Svalbard, and Early Jurassic (Pliensbachian) deposits of northern Germany, however questions the role of temperature on ikaite precipitation (Spielhagen and Tripati, 2009; Teichert and Luppold, 2013). Anomalously low carbon isotope values of Jurassic glendonites point to the involvement of methane as a possible carbon source for ikaite/glendonite formation. Terrestrial organic matter degradation is also frequently evoked as a potential source of carbon. The involved bio- and geochemical processes remains thus not well constrained. Here we present new geochemical data of a large number of glendonites specimens from the Lower and Middle Jurassic of northern Siberia and the Lena river middle flows (Bajocian, Bathonian, Pliensbachian). Carbon and oxygen isotopic values show comparable trends between the different sections. Bulk glendonites δ13C and δ18O values vary from 0.0 to -44.5o and -15.0 to -0.8 respectively and show a negative correlation. Some samples display similar low δ13C values as the Pliensbachian glendonites of Germany (Teichert and Luppold, 2013), suggesting thermogenic and/or biogenic methane sources. The range of carbon isotope values is comparable to those observed at other methane seeps deposits. Further investigations are needed to better constrain the carbon cycle in these particular environmental conditions. The role of microbial communities into ikaite/glendonite formation equally needs to be

  10. Temperature thresholds for Arctic plankton community metabolism: an experimental assessment

    Directory of Open Access Journals (Sweden)

    J. M. Holding

    2011-11-01

    Full Text Available Climate warming is especially severe in the Arctic, where the average temperature is increasing 0.4 °C per decade, two to three times higher than the global average rate. Furthermore, the Arctic has lost more than half its summer ice extent since 1980 and predictions suggest that the Arctic will be ice free in the summer as early as 2050, which could increase rate of warming. Predictions based on the metabolic theory of ecology assume that temperature increase will enhance metabolic rates and thus both the rate of primary production and respiration will increase. However, these predictions do not consider the specific metabolic balance of the communities. We tested experimentally the response of Arctic plankton communities to seawater temperature spanning from 1 °C to 10 °C. Two types of communities were tested, open-ocean Arctic communities from water collected in the Barents Sea and Atlantic influenced fjord communities from water collected in the Svalbard fjord system. Metabolic rates did indeed increase as suggested by metabolic theory, however these results suggest a temperature threshold of 5 °C, beyond which the metabolism of plankton communities shifts from autotrophic to heterotrophic. Barents Sea communities showed a much clearer threshold response to temperature manipulations than fjord communities.

  11. Early Holocene variability in the Arctic Gateway - High-resolution records reflecting Atlantic Water advection and ice coverage

    Science.gov (United States)

    Spielhagen, Robert F.; Bauch, Henning A.; Maudrich, Martin; Not, Christelle; Telesinski, Maciej M.; Werner, Kirstin

    2015-04-01

    The Arctic Gateway between Greenland and Svalbard is the main passage for the advection of Atlantic Water to the Arctic Ocean. Water temperature and intensity of this advection largely determine the degree of ice coverage which is fed by sea ice export from the north. Supported by a maximum in insolation, the Early Holocene was a period of extraordinarily strong advection and relatively high near-surface water temperatures in the eastern Nordic Seas (cf. Risebrobakken et al., 2011, Paleoceanography v. 26). Here we present a synthesis of radiocarbon-dated records from the northern and western part of this area, reaching from the SW Greenland Sea (73°N) to the Yermak Plateau (81°N) and revealing temporal and spatial differences in the development of the so-called Holocene Thermal Maximum (HTM). In the northern part of this region, the HTM started ca. 11-10.5 ka as indicated by rapidly increasing amounts of subpolar planktic foraminifers in the sediments. In the eastern Fram Strait and on the Yermak Plateau, our records of (sub)millennial scale resolution show that the maximum influx terminated already 2,000 years later (9-8 ka). Most likely, this development went along with a N-S relocation of the sea ice margin. According to the current stratigraphic model for a core with submillennial-scale resolution from Vesterisbanken seamount (73°N) in the Greenland Sea, the timing was different there. Increasing total amounts of planktic foraminifers in the sediment indicate an early (11-10 ka) reduction in sea ice coverage also in this region. However, evidence from subpolar planktic foraminifers for maximum Atlantic Water advection is younger (9-6 ka) than in the north. Apparently, the site in the SW Greenland Sea was affected by Atlantic Water in the Greenland Gyre that decoupled from the northward flowing Norwegian Atlantic Current/Westspitsbergen Current south of the Fram Strait. Thus, in a suite of events, strong Atlantic Water advection first affected the

  12. An Arctic perspective on dating Mid-Late Pleistocene environmental history

    DEFF Research Database (Denmark)

    Alexanderson, Helena; Backman, Jan; Cronin, Thomas M.;

    2014-01-01

    by radiocarbon, luminescence or cosmogenic exposure ages. Arctic Ocean deep-sea sediment successions can be correlated over large distances based on geochemical and physical property proxies for sediment composition, patterns in palaeomagnetic records and, increasingly, biostratigraphic data. Many...

  13. Environmental marine geology of the Arctic Ocean

    International Nuclear Information System (INIS)

    The Arctic Ocean and its ice cover are major regulators of Northern Hemisphere climate, ocean circulation and marine productivity. The Arctic is also very sensitive to changes in the global environment because sea ice magnifies small changes in temperature, and because polar regions are sinks for air pollutants. Marine geology studies are being carried out to determine the nature and rate of these environmental changes by study of modern ice and sea bed environments, and by interpretation of geological records imprinted in the sea floor sediments. Sea ice camps, an ice island, and polar icebreakers have been used to study both western and eastern Arctic Ocean basins. Possible early warning signals of environmental changes in the Canadian Arctic are die-back in Arctic sponge reefs, outbreaks of toxic dinoflagellates, and pesticides in the marine food chain. Eastern Arctic ice and surface waters are contaminated by freon and radioactive fallout from Chernobyl. At present, different sedimentary processes operate in the pack ice-covered Canadian polar margin than in summer open waters off Alaska and Eurasia. The geological records, however, suggest that a temperature increase of 1-4C would result in summer open water throughout the Arctic, with major changes in ocean circulation and productivity of waters off Eastern North America, and more widespread transport of pollutants from eastern to western Arctic basins. More studies of longer sediment cores are needed to confirm these interpretations, but it is now clear that the Arctic Ocean has been the pacemaker of climate change during the past 1 million years

  14. Environmental marine geology of the Arctic Ocean

    International Nuclear Information System (INIS)

    The Arctic Ocean and its ice cover are major regulators of Northern Hemisphere climate, ocean circulation and marine productivity. The Arctic is also very sensitive to changes in the global environment because sea ice magnifies small changes in temperature, and because polar regions are sinks for air pollutants. Marine geology studies are being carried out to determine the nature and rate of these environmental changes by study of modem ice and sea-bed environments, and by interpretation of geological records imprinted in the sea-floor sediments. Sea ice camps, an ice island, and polar icebreakers have been used to study both western and eastern Arctic Ocean basins. Possible early warning signals of environmental changes in the Canadian Arctic are die-back in Arctic sponge reefs, outbreaks of toxic dinoflagellates, and pesticides in the marine food chain. Eastern Arctic ice and surface waters are contaminated by freon and radioactive fallout from Chernobyl. At present, different sedimentary processes operate in the pack ice-covered Canadian polar margin than in summer open waters off Alaska and Eurasia. The geological records, however, suggest that a temperature increase of 1-4 degree C would result in summer open water throughout the Arctic, with major changes in ocean circulation and productivity of waters off Eastern North America, and more widespread transport of pollutants from eastern to western Arctic basins. More studies of longer sediment cores are needed to confirm these interpretations, but is is now clear that the Arctic Ocean has been the pacemaker of climate change during the past 1 million years

  15. Arctic root-associated fungal community composition reflects environmental filtering.

    Science.gov (United States)

    Blaalid, Rakel; Davey, Marie L; Kauserud, Håvard; Carlsen, Tor; Halvorsen, Rune; Høiland, Klaus; Eidesen, Pernille B

    2014-02-01

    There is growing evidence that root-associated fungi have important roles in Arctic ecosystems. Here, we assess the diversity of fungal communities associated with roots of the ectomycorrhizal perennial herb Bistorta vivipara on the Arctic archipelago of Svalbard and investigate whether spatial separation and bioclimatic variation are important structuring factors of fungal community composition. We sampled 160 plants of B. vivipara from 32 localities across Svalbard. DNA was extracted from entire root systems, and 454 pyrosequencing of ITS1 amplicons was used to profile the fungal communities. The fungal communities were predominantly composed of Basidiomycota (55% of reads) and Ascomycota (35%), with the orders Thelephorales (24%), Agaricales (13.8%), Pezizales (12.6%) and Sebacinales (11.3%) accounting for most of the reads. Plants from the same site or region had more similar fungal communities to one another than plants from other sites or regions, and sites clustered together along a weak latitudinal gradient. Furthermore, a decrease in per-plant OTU richness with increasing latitude was observed. However, no statistically significant spatial autocorrelation between sites was detected, suggesting that environmental filtering, not dispersal limitation, causes the observed patterns. Our analyses suggest that while latitudinal patterns in community composition and richness might reflect bioclimatic influences at global spatial scales, at the smaller spatial scale of the Svalbard archipelago, these changes more likely reflect varied bedrock composition and associated edaphic factors. The need for further studies focusing on identifying those specific bioclimatic and edaphic factors structuring root-associated fungal community composition at both global and local scales is emphasized. PMID:24320873

  16. Modelling past and future permafrost conditions in Svalbard

    OpenAIRE

    B. Etzelmüller; T. V. Schuler; K. Isaksen; H. H. Christiansen; H. Farbrot; R. Benestad

    2010-01-01

    Variations in ground thermal conditions in Svalbard were studied based on measurements and theoretical calculations. Ground temperature data was used to calibrate a transient heat flow model describing depth and time variations in temperatures. The model was subsequently forced with historical surface air temperature data records and downscaled global climate model runs to project ground temperatures. We discuss ground temperature development since the early 20th century, and the thermal resp...

  17. Palynology of the Permian succession of Spitsbergen, Svalbard

    OpenAIRE

    Mangerud, G.; Konieczny, R. M.

    1993-01-01

    Palynological investigations of 16 sections from Spitsbergen, Svalbard, covering the uppermost Carboniferous, Permian and lowermost Triassic succession have been carried out. Because of general poor preservation and barrenness of the majority of the samples, it was not possible to establish a formal zonation for the Permian succession. The study resulted, however, in the recognition of three Permian palynological assemblages, restricted downwards by a Carboniferous assemblage and upwards by a...

  18. Effect of wind on Svalbard reindeer fur insulation

    Directory of Open Access Journals (Sweden)

    Christine Cuyler

    2002-06-01

    Full Text Available The heat transfer through Svalbard reindeer (Rangifer tarandus platyrhynchus fur samples was studied with respect to wind velocity, season and animal age. A total of 33 dorsal fur sections were investigated using a wind tunnel. Insulation varied with season (calving, summer, autumn and winter. At zero wind velocity, fur insulation was significantly different between seasons for both calf and adult fur samples. At the same time, there was no significant difference between calf and adult insulation for the summer, autumn and winter seasons. Calf fur insulated as well as adult fur. Winter insulation of Svalbard reindeer was approximately 3 times that of summer. Increasing wind veloci¬ty increased heat loss, however, the increase was not dramatic. When wind coefficients (slope of the heat transfer regression lines were compared, between season and between calf and adult, no significant differences were reported. All fur samples showed similar increases in heat transfer for wind velocities between 0 and 10 m.s-1. The conductance of winter fur of Svalbard reindeer was almost half that of caribou fur. Also, conductance was not as greatly influenced by wind as caribou fur

  19. High sedimentation rates in the Early Triassic after latest Permian mass extinction: Carbonate production is main factor in non-Arctic regions

    Science.gov (United States)

    Horacek, Micha; Brandner, Rainer

    2016-04-01

    A substantial change in sedimentation rates towards higher values has been documented from the Late Permian to the Lower Triassic. Although it is assumed and also has been shown that the deposition of siliciclastic material increased in the Lower Triassic due to stronger erosion because of loss of land cover and increased chemical and physical weathering with extreme climate warming, the main sediment production occurred by marine carbonate production. Still, carbonate production might have been significantly influenced by weathering and erosion in the hinterland, as the transport of dust by storms into the ocean water probably was a main nutrient source for microbial carbonate producers, because "normal" nutrient supply by ocean circulation, i. e. upwelling was strongly reduced due to the elevated temperatures resulting in water-column stratification . Sediment accumulation was also clearly influenced by the paleo-geographic and latitudinal position, with lower carbonate production and sedimentation rates in moderate latitudes. The existence of a "boundary clay" and microbial carbonate mounds and layers in the immediate aftermath of the latest Permian mass extinction points towards a development from a short-timed acid ocean water - resulting in a carbonate production gap and the deposition of the boundary clay towards the deposition of the microbial mounds and layers due to the microbial production of micro-environments with higher alkalinity allowing the production of carbonate. After the return of the ocean water to normal alkalinity planktic production of carbonate resulted in a very high sedimentation rate, especially taking into account the absence of carbonate producing eukaryotic algae and animals.

  20. The importance of tidewater glaciers for marine mammals and seabirds in Svalbard, Norway

    Science.gov (United States)

    Lydersen, Christian; Assmy, Philipp; Falk-Petersen, Stig; Kohler, Jack; Kovacs, Kit M.; Reigstad, Marit; Steen, Harald; Strøm, Hallvard; Sundfjord, Arild; Varpe, Øystein; Walczowski, Waldek; Weslawski, Jan Marcin; Zajaczkowski, Marek

    2014-01-01

    Approximately 60% of Svalbard's land areas are glaciated at the present time. The Archipelago has more than 1100 glaciers (> 1 km2) and 163 of these are “tidewater glaciers” - that is glaciers that terminate (with their calving front) at the sea. It has been known for a long time that these glacier front areas are important feeding areas for seabirds and marine mammals. Herein, we review current knowledge regarding the importance of these areas for these animals and reflect upon the processes that create these apparent “hotspots”. Kittiwakes Rissa tridactyla, routinely dominate avian assemblages in front of glaciers in Svalbard, but fulmars Fulmarus glacialis, ivory gulls Pagophila eburnea and glaucous gulls Larus hyperboreus also contribute to aggregations, which can sometimes comprise many thousands of individuals. The birds are often found in the so-called “brown zone”, which is an area in front of tidewater glaciers that is ice-free due to currents and muddy due to suspended sediments. Animals at these sites typically have their stomachs full of large zooplankton or fish. These brown zones are also foraging hotspots for Svalbard's ringed seals (Pusa hispida) and white whales (Delphinapterus leucas). Prime breeding habitat for ringed seals in Svalbard occurs deep in the fjords where ice pieces calved from the glacier fronts become frozen into land-fast sea-ice, promoting the accumulation of snow to a depth suitable for ringed seal females to dig out birth lairs above breathing holes in the ice. These pupping areas are important hunting areas for polar bears (Ursus maritimus) in spring, especially female bears with cubs of the year during the period following emergence from the winter/birthing den. Glacier-ice pieces floating in coastal areas are also important for all seal species in the region as dry platforms during moulting and also as general resting platforms for both birds and seals. During the last decade there have been several years with a

  1. A Geo Information System (GIS) for circum-arctic coastal dynamics

    OpenAIRE

    Rachold, Volker; Lack, M.; Mikhail N Grigoriev

    2003-01-01

    Coastal erosion forms a major source of the sediment, organic carbon and nutrient flux into the arctic basin. Recent studies indicate that sediment input resulting from the erosion of ice-rich, permafrost-dominated coasts might be equal to or greater than river input. The program Arctic Coastal Dynamics (ACD) has been developed to improve our understanding of circum-arctic coastal dynamics as a function of environmental forcing, coastal geology, geocryology and morphodynamic behavior. Under t...

  2. Depositional history of the Upper Triassic Kapp Toscana Group on Svalbard, Norway, inferred from palynofacies analysis and organic geochemistry

    Science.gov (United States)

    Mueller, Steven; Veld, Harry; Nagy, Jenö; Kürschner, Wolfram M.

    2014-08-01

    Upper Triassic sediments in the Svalbard Archipelago were deposited in several transgressive-regressive cycles. Understanding their deposition and distribution is of vital importance because of their potential as hydrocarbon reservoir rocks. In this study we integrate palynofacies with organic geochemistry in order to reconstruct the depositional environment of the upper Botneheia Fm up to the lower the Knorringfjellet Fm from two sections located in central Spitsbergen, for which distinctive palynofacies zones have been distinguished. These are mainly terrestrially dominated but occasionally contain amorphous organic matter and marine palynomorphs. Rock-Eval pyrolysis reveals overall mature kerogen type III/IV samples. Our results indicate that at least partially restricted marine conditions prevailed during deposition of the Botneheia Fm. The Botneheia Fm is overlain by a regressive cycle from the lower part of the Tschermakfjellet Fm up to the top of the De Geerdalen Fm with terrestrially dominated palynofacies assemblages. The Knorringfjellet Fm contains increased marine palynofacies and marine dinoflagellate cysts, which is in accordance with a transgression at the base of this unit. This study integrates for the first time in the Spitsbergen area quantitative palynofacies and sedimentary organic matter characterization, and shows the generally accepted paleo-environmental development for the Svalbard Archipelago.

  3. Arctic Wears - Perspectives on Arctic Clothing

    OpenAIRE

    Konola, Sanna; Kähkönen, Päivi

    2015-01-01

    Arctic issues are rising around us on every field at the point of view of environment, sustainability, climate change, indigenous peoples’ rights, design and society, snow and ice building knowledge, challenges and possibilities in Arctic areas. The Arctic is written in Finland’s future strategies, and in 2017 Finland assumes the chairmanship of Arctic Council. In the northernmost university of European Union, University of Lapland, the northern issues have always been written in the DNA ...

  4. Mesozooplankton community development at elevated CO2 concentrations: results from a mesocosm experiment in an Arctic fjord

    Directory of Open Access Journals (Sweden)

    J. Czerny

    2012-08-01

    Full Text Available The increasing CO2 concentration in the atmosphere caused by burning fossil fuels leads to increasing pCO2 and decreasing pH in the world oceans. These changes may have severe consequences for marine biota, especially in cold-water ecosystems due to higher solubility of CO2. However, studies on the response of mesozooplankton communities to elevated pCO2 are yet lacking. In order to test whether abundance and taxonomic composition change with pCO2, we have sampled nine mesocosms, which were deployed in Kongsfjorden, an Arctic fjord at Svalbard, and were adjusted to eight CO2 concentrations, initially ranging from 185 μatm to 1420 μatm. Samples were taken weekly over a six-week period with an Apstein net (55 μm mesh size in all mesocosms and the surrounding fjord. In addition, sediment trap samples, taken every second day in the mesocosms, were analyzed to account for losses due to vertical migration and mortality. The taxonomic analysis revealed that meroplanktonic larvae (cirripeds, polychaetes, bivalves, gastropod, and decapods dominated in the mesocosms while copepods (Calanus spp., Oithona similis, Acartia longiremis and Microsetella norvegica were found in lower abundances. In the fjord copepods prevailed for most of our study. With time, abundance and taxonomic composition developed similarly in all mesocosms; the pCO2 had no significant effect on the overall community structure. However, single taxa responded to elevated CO2 concentrations. The ratio of cirripedia nauplii to cypris larvae, the next developmental stage, in the sediment traps averaged over the entire experiment increased with pCO2 and this suggests that increased pCO2 may have delayed their development. Also, the number of bivalves, averaged over the experimental period, decreased significantly with increasing pCO2. The nature of the CO2 effect, either direct or indirect, remains open and needs to be addressed in future.

  5. Microbial nitrogen cycling in Arctic snowpacks

    International Nuclear Information System (INIS)

    Arctic snowpacks are often considered as chemical reactors for a variety of chemicals deposited through wet and dry events, but are overlooked as potential sites for microbial metabolism of reactive nitrogen species. The fate of deposited species is critical since warming leads to the transfer of contaminants to snowmelt-fed ecosystems. Here, we examined the role of microorganisms and the potential pathways involved in nitrogen cycling in the snow. Next generation sequencing data were used to follow functional gene abundances and a 16S rRNA (ribosomal ribonucleic acid) gene microarray was used to follow shifts in microbial community structure during a two-month spring-time field study at a high Arctic site, Svalbard, Norway (79° N). We showed that despite the low temperatures and limited water supply, microbial communities inhabiting the snow cover demonstrated dynamic shifts in their functional potential to follow several different pathways of the nitrogen cycle. In addition, microbial specific phylogenetic probes tracked different nitrogen species over time. For example, probes for Roseomonas tracked nitrate concentrations closely and probes for Caulobacter tracked ammonium concentrations after a delay of one week. Nitrogen cycling was also shown to be a dominant process at the base of the snowpack. (letter)

  6. Plutonium in algae, sediments and biota in the Barents, Pechora and Kara seas

    International Nuclear Information System (INIS)

    The 239,240Pu concentrations measured in the sediment, macro algae and benthic fauna were very low in the Russian Arctic seas, and in fish, seabirds and seals usually below the detection limit. The 238Pu/ 239,240Pu ratios suggest that global fallout is the main source of the plutonium. Fallout level Pu isotope ratios, 0.02 - 0.04, were also found in surface vegetation and soil samples from fifteen locations covering Svalbard, Franz Joseph Land Archipelago, coastal areas and islands of the Barents, Pechora and White seas, including the southern coast of Novaya Zemlya, Kola Bay and the River Yenisey estuary. The areal 239,240Pu concentrations of the terrestrial sampling plots varied from 9 to 32Bq/m2. Significantly enhanced 238Pu/239,240Pu ratios of 0.10 - 0.18 were detected only in the Kola Bay in sediment layers outside and to the south of the Atomflot civilian nuclear ice-breaker base. The enhanced isotope ratios in this section of the Kola Bay were verified by triplicate determinations. The highest ratios were found at a depth 6-7.5 cm, and not in the surface sediment layers, indicating a larger previous release. Plutonium is not concentrated in the marine foodchains. Accumulation of 239,240Pu was detected in some species of benthic fauna; in molluscs mainly in the shells compared to the soft edible parts of the specimen. Plutonium was not detected higher in the marine food-chain. The 239,240Pu concentrations measured in the bones and soft tissues of commercial fish species, sea birds and seals were below the detection limit. (author)

  7. Food and soil-borne Penicillia in Arctic environments: Chemical diversity

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian

    Penicillia are very common inhabitants of cold environments, including arctic soil, plants, animals, and foods. We have investigated the mycobiota of Greenland inland ice and soil, and found a very unique and pronounced diversity among the Penicillia. Nearly all species were new to science....... The species found in inland ice were both of the soil-borne type, and Penicillia that grow and sporulate well at 25°C. The latter group of Penicillia have been found earlier in refrigerated foods, including P. nordicum, and in glacier ice and melting water from Svalbard (se Sonjak et al., this conference......). This “food-borne group” of arctic fungi also contained some new species, but not as many as in arctic soil. The chemical diversity of the Penicillium species was remarkably high and in most cases even larger than the chemical diversity of Penicillia in the tropics. Several new secondary metabolites were...

  8. Arctic studies

    International Nuclear Information System (INIS)

    Idaho National Engineering Laboratory (INEL) conducted a study of contamination of the Arctic Ocean and surrounding areas in order to better understand the severity of the problem and identify possible parallels in the United States. The findings were published in a quarterly report as a part of this technical task plan (TTP). While many radioactive and hazardous material contamination sites in this region have been identified, official Russian statements indicate that contaminant concentrations are within normal limits and are currently confined to specific areas

  9. High-Resolution Seismic Definition of the Distribution of Gas in the West Svalbard Margin

    Science.gov (United States)

    Minshull, T. A.; Westbrook, G. K.; Marin-Moreno, H.; Marsset, B.; Ker, S.; Sarkar, S.; Vardy, M. E.; Henstock, T.

    2014-12-01

    The widespread presence of gas beneath the seabed west of Svalbard is shown by negative-polarity high-amplitude reflectors (nephars), imaged in high-resolution near-surface and deep-towed seismic reflection data. The principal controls on the presence of gas are the gas hydrate stability zone (GHSZ), from which free gas is generally excluded, and stratigraphic control of permeable layers. A widespread bottom-simulating reflector (BSR) beneath the lower-mid continental slope indicates gas at the base of the GHSZ. The depth of the base of the GHSZ predicted by a numerical model that takes in to account variation in ocean temperature over the past two thousand years, is consistent with the depth of the BSR, even at its shallowest depth, where a steady-state model places base of the GHSZ shallower than the BSR. Similarly, farther up slope, where the BSR loses it coherency, the depths of the shallowest nephars are compatible with the predicted depth of the base of the GHSZ from the time-dependent model, but are about three times deeper than the predicted steady-state depth of the BSR. This approach to defining the limits of the GHSZ is not precise, as it depends upon the presence of gas. In the shallow sediment sequence, which has a high proportion of glacigenic sediments, gas is restricted to a smaller number of permeable units than in the contourite-dominated sequence farther down the continental slope. Where the seabed is shallower than the GHSZ, numerous plumes of methane gas ascend from the seabed, and gas, which has migrated up slope through dipping permeable layers, locally ponds beneath a thin veneer of unconformable glacial and post-glacial sediments on the continental shelf.

  10. Microbial community development on deglaciated soils in high arctic (Svalbard) in comparison to sub-arctic continental regions (Scandinavia)

    Czech Academy of Sciences Publication Activity Database

    Chroňáková, Alica; Bryndová, Michala; Kaštovská, E.; Devetter, Miloslav; Lukešová, Alena

    České Budějovice : Faculty of Science, University of South Bohemia in České Budějovice, 2015. s. 31. ISBN 978-80-7394-528-2. [International Conference on Polar and Alpine Microbiology /6./. 06.09.2015-10.09.2015, České Budějovice] R&D Projects: GA MŠk(CZ) LD13046 Grant ostatní: GA MŠk(CZ) LM2010009 Institutional support: RVO:60077344 Keywords : soil development * next generation sequencing * bacterial communities * nutrients * chronosequences Subject RIV: EH - Ecology , Behaviour

  11. At-sea observations of the spring migration and pair bonding of ivory gulls (Pagophila eburnea around Svalbard and East Greenland

    Directory of Open Access Journals (Sweden)

    Henrik Kylin

    2011-03-01

    Full Text Available Because of logistical constraints little previous information exists on ivory gulls (Pagophila eburnea in the waters around Svalbard and the east coast of Greenland in late winter/early spring. The Swedish Arctic Ocean 2002 expedition investigated these areas at that time of year and in this paper I report on the observations of ivory gulls made during the expedition. The ivory gull was essentially absent from open waters but was the most common seabird in areas with pack ice, showing behavioural differences depending on local conditions. Generally, the number of ivory gulls was low when there was little plankton in the water. Ivory gulls followed the ship depending on the availability of food items in the wake and also depending on competition from other species, particularly glaucous gulls (Larus hyperboreus. Although ivory gulls were present in most of Fram Strait and the northern part of the East Greenland Current during 6 and 19 May, sightings were few and correlated to the amount of plankton in the water. Aggregations of several hundred were seen on the ice where copulation and other social interaction took place. A previously undescribed pair bonding behaviour during which females seemed to select between two competing males was observed north of Svalbard on 30 April–1 May. Off Scoresby Sound on 25 May, more than 700 birds were seen migrating north, while farther south along the Greenland coast on 30 May there was little indication of migration although many ivory gulls were seen.

  12.  Winter time burst of CO2 from the High Arctic soils of Svalbard

    DEFF Research Database (Denmark)

    Friborg, Thomas; Hansen, Birger; Elberling, Bo; Jensen, Louise Askær; Søndergaard, Jens Ernst; Mastepanov, Mikhail

    relatively few measurements which appear to give small and constant emission rates. Further, most studies of the processes behind winter time emission of CO2 conclude that the flux during this time of year can be linked to the respiratory release of CO2 from soil micro organisms, which is temperature...

  13. Myxozoa in high Arctic: Survey on the central part of Svalbard archipelago

    Czech Academy of Sciences Publication Activity Database

    Kodádková, Alena; Dyková, I.; Tyml, Tomáš; Ditrich, O.; Fiala, Ivan

    2014-01-01

    Roč. 3, č. 1 (2014), s. 41-56. ISSN 2213-2244 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Artic * Marine urinary clade * Myxosporea * Phylogeny * Schulmania * Zschokkella Subject RIV: EG - Zoology

  14. Phytochemical profiles and antioxidant potential of four Arctic vascular plants from Svalbard

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, P.; Singh, S.M.; DeSouza, L.; Wahidullah, S.

    resistant towards dissociation. Each ion is likely to represent a single component of the mixture rather than being fragments of other heavier ions. The ionization behaviour is typical of neutral oligosaccharides, due to their capability to form strong...) The phytoecdysteroid profiles of 7 species of Silene (Caryophyllaceae). Arch Insect Biochem Physio 72:234–248 FIGURE LEGENDS Figure 1: Structures of compounds identified in Silene uralensis: (1) Ethyl benzene, (2) Benzoyl selenol, (3) Benzaldehyde, (4...

  15. The first magnetotelluric image of the lithospheric-scale geological architecture in central Svalbard, Arctic Norway

    Directory of Open Access Journals (Sweden)

    Thomas I. Beka

    2015-12-01

    Full Text Available Magnetotelluric data, collected from 30 stations on Spitsbergen as part of a reconnaissance geothermal resource assessment along a profile with 0.5–3-km spacing in 0.003–1000-s period range, were used to develop a lithospheric-scale two-dimensional (2D resistivity model, heretofore unavailable for the region. Inverting the determinant of the impedance tensor in 2D, we found the smoothest model fitting the data within a specified tolerance level. We justified the model by perturbing it, performing sensitivity analysis and re-running the inversion with a different algorithm and starting models. From our final model, we constructed a crustal-scale stratigraphic framework, using it to estimate the depth of major geological features and to locate structural deformations. The 2D resistivity model indicates a shallow low resistive (1000 Ωm east of the Billefjorden Fault Zone. Underneath, a (possibly Devonian basin is imaged as a thick conductive anomaly stretching >15 km downwards. Beneath a deformed Paleozoic–Mesozoic successions, an uplifted pre-Devonian shallow basement (>3000 Ωm is revealed. We estimated a thin lithosphere, in the range of ca. 55–100 km thick, that could explain the area's elevated surface heat flow (ca. 60–90 mW/m2, consistent with the calculated depth of thermal lithosphere heat-base boundaries for a partially melting mantle. The model indicates a possible replenishment pathway of upward heat transport from the shallow convective mantle to the composite crustal conductive units. This is encouraging for low-enthalpy geothermal development.

  16. Demographic population structure and fungal associations of plants colonizing High Arctic glacier forelands, Petuniabukta, Svalbard

    Czech Academy of Sciences Publication Activity Database

    Těšitel, J.; Těšitelová, T.; Bernardová, A.; Drdová, Edita; Lučanová, Magdalena; Klimešová, Jitka

    2014-01-01

    Roč. 33, č. 20797 (2014). ISSN 0800-0395 Institutional support: RVO:61389030 ; RVO:67985939 Keywords : Colonizer * deglaciation * endophyte Subject RIV: DO - Wilderness Conservation; EF - Botanics (BU-J) Impact factor: 1.141, year: 2014

  17. Arctic Browning: vegetation damage and implications for carbon balance.

    Science.gov (United States)

    Treharne, Rachael; Bjerke, Jarle; Emberson, Lisa; Tømmervik, Hans; Phoenix, Gareth

    2016-04-01

    'Arctic browning' is the loss of biomass and canopy in Arctic ecosystems. This process is often driven by climatic and biological extreme events - notably extreme winter warm periods, winter frost-drought and severe outbreaks of defoliating insects. Evidence suggests that browning is becoming increasingly frequent and severe at the pan-arctic scale, a view supported by observations from more intensely observed regions, with major and unprecedented vegetation damage reported at landscape (>1000km2) and regional (Nordic Arctic Region) scales in recent years. Critically, the damage caused by these extreme events is in direct opposition to 'Arctic greening', the well-established increase in productivity and shrub abundance observed at high latitudes in response to long-term warming. This opposition creates uncertainty as to future anticipated vegetation change in the Arctic, with implications for Arctic carbon balance. As high latitude ecosystems store around twice as much carbon as the atmosphere, and vegetation impacts are key to determining rates of loss or gain of ecosystem carbon stocks, Arctic browning has the potential to influence the role of these ecosystems in global climate. There is therefore a clear need for a quantitative understanding of the impacts of browning events on key ecosystem carbon fluxes. To address this, field sites were chosen in central and northern Norway and in Svalbard, in areas known to have been affected by either climatic extremes or insect outbreak and subsequent browning in the past four years. Sites were chosen along a latitudinal gradient to capture both conditions already causing vegetation browning throughout the Norwegian Arctic, and conditions currently common at lower latitudes which are likely to become more damaging further North as climate change progresses. At each site the response of Net Ecosystem CO2 Exchange to light was measured using a LiCor LI6400 Portable Photosynthesis system and a custom vegetation chamber with

  18. Arctic Ocean Scientific Drilling: The Next Frontier

    Directory of Open Access Journals (Sweden)

    Ruediger Stein

    2010-04-01

    Full Text Available The modern Arctic Ocean appears to be changing faster than any other region on Earth. To understand the potential extent of high latitude climate change, it is necessary to sample the history stored in the sediments filling the basins and covering the ridges of the Arctic Ocean. These sediments have been imaged with seismic reflection data, but except for the superficial record, which has been piston cored, they have been sampled only on the Lomonosov Ridge in 2004 during the Arctic Coring Expedition (ACEX-IODP Leg 302; Backman et al., 2006 and in 1993 in the ice-free waters in the Fram Strait/Yermak Plateau area (ODP Leg 151; Thiede et al., 1996.Although major progress in Arctic Ocean research has been made during the last few decades, the short- and long-term paleoceanographic and paleoclimatic history as well as its plate-tectonic evolution are poorly known compared to the other oceans. Despite the importance of the Arctic in the climate system, the database we have from this area is still very weak. Large segments of geologic time have not been sampled in sedimentary sections. The question of regional variations cannot be addressed.

  19. Response of bacterioplankton activity in an Arctic fjord system to elevated pCO2: results from a mesocosm perturbation study

    OpenAIRE

    J. Piontek; C. Borchard; Sperling, M.; K. G. Schulz; Riebesell, U.; Engel, A.

    2013-01-01

    The effect of elevated seawater carbon dioxide (CO2) on the activity of a natural bacterioplankton community in an Arctic fjord system was investigated by a mesocosm perturbation study in the frame of the European Project on Ocean Acidification (EPOCA). A pCO2 range of 175–1085 μatm was set up in nine mesocosms deployed in the Kongsfjorden (Svalbard). The activity of natural extracellular enzyme assemblages increased in response to acidification. Rates of β-glucosidase ...

  20. Cesium-137 contamination in Arctic Ocean ice

    International Nuclear Information System (INIS)

    Sea ice and ice-borne sediment samples were collected across the western Arctic basin on the joint US/Canada Arctic Ocean Section during August 1994. Samples were processed on board and returned at the completion of the cruise to Oak Ridge National Laboratory for analysis. Sediment was observed on the surface and in the ice from the southern ice limit in the Chukchi Sea to the North Pole. Preliminary results on the ice-borne sediment samples show widespread elevated concentrations of 137Cs, ranging from 4.9 to 73 mBq g dry weight-1. An analysis of the measurements indicate that sea ice is primary transport mechanism by which contaminated sediments are redistributed throughout the Arctic Ocean and possibly exported into the Greenland Sea and North Atlantic through Fram Strait. The wide variability in the ice-borne sediment concentrations of 137Cs measured along the transect argues that contaminants incorporated on the Siberian shelves can follow much more variable trajectories than is suggested by mean ice drift calculations. 2 figs

  1. Ice-cored moraine degradation mapped and quantified using an unmanned aerial vehicle: A case study from a polythermal glacier in Svalbard

    Science.gov (United States)

    Tonkin, T. N.; Midgley, N. G.; Cook, S. J.; Graham, D. J.

    2016-04-01

    Ice-cored lateral-frontal moraines are common at the margins of receding high-Arctic valley glaciers, but the preservation potential of these features within the landform record is unclear. Recent climatic amelioration provides an opportunity to study the morphological evolution of these landforms as they de-ice. This is important because high-Arctic glacial landsystems have been used as analogues for formerly glaciated areas in the mid-latitudes. This study uses SfM (Structure-from-Motion) photogrammetry and a combination of archive aerial and UAV (unmanned aerial vehicle) derived imagery to investigate the degradation of an ice-cored lateral-frontal moraine at Austre Lovénbreen, Svalbard. Across the study area as a whole, over an 11-year period, the average depth of surface lowering was - 1.75 ± 0.89 m. The frontal sections of the moraine showed low or undetectable rates of change. Spatially variable rates of surface lowering are associated with differences in the quantity of buried ice within the structure of the moraine. Morphological change was dominated by surface lowering, with limited field evidence of degradation via back-wastage. This permits the moraine a greater degree of stability than previously observed at other sites in Svalbard. It is unclear whether the end point will be a fully stabilised ice-cored moraine, in equilibrium with its environment, or an ice-free lateral-frontal moraine complex. Controls on geomorphological change (e.g. topography and climate) and the preservation potential of the lateral-frontal moraine are discussed. The methods used by this research also demonstrate the potential value of SfM photogrammetry and unmanned aerial vehicles for monitoring environmental change and are likely to have wider applications in other geoscientific sub-disciplines.

  2. Quantifying Methane Emissions from the Arctic Ocean Seabed to the Atmosphere

    Science.gov (United States)

    Platt, Stephen; Pisso, Ignacio; Schmidbauer, Norbert; Hermansen, Ove; Silyakova, Anna; Ferré, Benedicte; Vadakkepuliyambatta, Sunil; Myhre, Gunnar; Mienert, Jürgen; Stohl, Andreas; Myhre, Cathrine Lund

    2016-04-01

    Large quantities of methane are stored under the seafloor in the shallow waters of the Arctic Ocean. Some of this is in the form of hydrates which may be vulnerable to deomposition due to surface warming. The Methane Emissions from Arctic Ocean to Atmosphere MOCA, (http://moca.nilu.no/) project was established in collaboration with the Centre for Arctic Gas Hydrate, Environment and Climate (CAGE, https://cage.uit.no/). In summer 2014, and summer and autumn 2015 we deployed oceanographic CTD (Conductivity, Temperature, Depth) stations and performed state-of-the-art atmospheric measurements of CH4, CO2, CO, and other meteorological parameters aboard the research vessel Helmer Hanssen west of Prins Karl's Forland, Svalbard. Air samples were collected for isotopic analysis (13C, 2H) and quantification of other hydrocarbons (ethane, propane, etc.). Atmospheric measurements are also available from the nearby Zeppelin Observatory at a mountain close to Ny-Ålesund, Svalbard. We will present data from these measurements that show an upper constraint of the methane flux in measurement area in 2014 too low to influence the annual CH4 budget. This is further supported by top-down constraints (maximum release consistent with observations at the Helmer Hansen and Zeppelin Observatory) determined using FLEXPART foot print sensitivities and the OsloCTM3 model. The low flux estimates despite the presence of active seeps in the area (numerous gas flares were observed using echo sounding) were apparently due to the presence of a stable ocean pycnocline at ~50 m.

  3. Digestion of energy and nutrients in Svalbard reindeer

    Directory of Open Access Journals (Sweden)

    Hans Staaland

    1988-06-01

    Full Text Available Feeding trials with 5 male Svalbard reindeer, Rangifer tarandus platyrhynchus Vrolik were conducted at the Man and the Biosphere (MAB Research Station in Adventdalen, Svalbard. Five different diets were used, 1: commercial reindeer food, (RF-71, 2: a mixture of locally harvested grasses and sedges (mainly Dupontia pelligera and Eriphorum scheusczeri, 3: a pure moss (Pleurozium scheberi diet, 4: a lichen diet using the dominant Svalbard species Cetraria delisei, and 5: a mixed diet of RF-71, moss (P. schreberi and lichens (mainly Cladonia alpestris and Cladonia rangiferina. When fed the RF-71 diet the digestibility by Svalbard and Norwegian reindeer were similar with respect to dry matter (DM 75 v 74% and crude protein (CP 74 v 70% as were the availabilities of P (72 v 76% a and Ca (18 v 36% in the diet. The mixture of grasses and sedges was highly digestible with respect to DM ((66,5% but had low availabilities of Ca (12%, Mg (10% and P (-11%. DM digestibility of the lichen C delisei was low (33% however this lichen could constitute a good source of Ca. Moss palatability was very low (174-252 g or 9-13g/kg 0 75 intake daily. DM, CP and energy digestibilities, respectively 48, 53 and 49%, and the availabilities of P (66% and Ca (20% were indicative that they could add to the energy and protein intake while contributing significantly to nutrient balance of Svalbard reindeer when present in a mixed diet.Fordøyelse av energi og næringsstoffer hos Svalbard-rein.Abstract in Norwegian / Sammendrag: Ved MAB-stasjonen i Adventdalen på Svalbard ble det utført foringsforsøk med fem voksne bukker av Svalbardrein, Rangifer tarandus platyrhynchus Vrolik. Det ble nyttet fem forskjellige forty per, 1: pelletert reinfor, RF71, 2: en blanding av gras og siv høstet i Adventdalen (vesentlig Dupontia pelligera og Eriophorum scheuchzeri, 3: en ren mosediett (Pleurozium schreberi, 4: lav av den vanlige Svalbard -arten, Cetraria delisei, 5: en blandet diett av RF

  4. Modelling past and future permafrost conditions in Svalbard

    Directory of Open Access Journals (Sweden)

    B. Etzelmüller

    2010-10-01

    Full Text Available Variations in ground thermal conditions in Svalbard were studied based on measurements and theoretical calculations. Ground temperature data was used to calibrate a transient heat flow model describing depth and time variations in temperatures. The model was subsequently forced with historical surface air temperature data records and downscaled global climate model runs to project ground temperatures. We discuss ground temperature development since the early 20th century, and the thermal responses in relation to ground characteristics and snow cover. The modelled ground temperatures show a gradually increase since the end of the Little Ice Age (mid 19th century on Svalbard, by about 1.5 °C to 2 °C at 20 m depth. The active layer thickness (ALT is modelled to have increased slightly, with the rate of increase depending on water content of the near-surface layers. The used scenario runs predict a significant increase in ground temperatures and an increase of ALT depending on soil characteristics.

  5. The evolution of Arctic marine mammals.

    Science.gov (United States)

    Harington, C R

    2008-03-01

    This review deals only with the evolutionary history of core Arctic marine mammals: polar bear (Ursus maritimus), walrus (Odobenus rosmarus), bearded seal (Erignathus barbatus), harp seal (Pagophilus groenlandica), ringed seal (Phoca hispida), bowhead whale (Balaena mysticetus), white whale (Delphinapterus leucas), and narwhal (Monodon monoceras). Sections on the evolutionary background of pinnipeds and whales help to provide a better perspective on these core species. Polar bears stemmed from brown bears about the Early to Middle Pleistocene. Fossils are rare; the earliest records are from approximately Early Weichselian deposits of Kew Bridge, London, and Svalbard. Existing Pacific and Atlantic walruses probably arose from splitting of a former Holarctic range during a Pleistocene glacial phase of extensive sea ice in the Canadian Arctic. The earliest known bearded seal remains are from Early to Middle Pleistocene deposits of Norfolk, England, and Cape Deceit, Alaska. Other Pleistocene fossils of this species are recorded from the North Sea, southwestern Sweden, and the Champlain Sea that existed in eastern North America approximately 12 000-10000 BP. The harp seal is the commonest pinniped in the Weichselian deposits of the southern North Sea. The earliest recorded fossil is from about 2 million years ago (2 Ma), from Ocean Point, Alaska. The earliest known Pleistocene ringed seal fossils are from last interglacial deposits near Teshekpuk Lake, Alaska, and Thule, Greenland, although an earlier (3 Ma?) specimen from Malaspina, Alaska, has been reported. This species seems to have been relatively abundant along the coasts of Prince of Wales Island, Alaska, during the Last Glacial Maximum. The bowhead whale probably originated in the high latitudes of the Northern Hemisphere. The earliest (mid-Wisconsinan) Canadian remains are from Ellesmere and Devon islands. More than 400 radiocarbon-dated bowhead remains have been used to reconstruct Holocene sea ice history in

  6. Geographical distribution of organochlorine pesticides (OCPs) in polar bears (Ursus maritimus) in the Norwegian and Russian Arctic

    Science.gov (United States)

    Lie, E.; Bernhoft, A.; Riget, F.; Belikov, Stanislav; Boltunov, Andrei N.; Derocher, A.E.; Garner, G.W.; Wiig, O.; Skaare, J.U.

    2003-01-01

    Geographical variation of organochlorine pesticides (OCPs) was studied in blood samples from 90 adult female polar bear (Ursus maritimus) from Svalbard, Franz Josef Land, Kara Sea, East-Siberian Sea and Chukchi Sea. In all regions, oxychlordane was the dominant OCP. Regional differences in mean levels of HCB, oxychlordane, trans-nonachlor, ??-HCH, ??-HCH and p,p???-DDE were found. The highest levels of oxychlordane, trans-nonachlor and DDE were found in polar bears from Franz Josef Land and Kara Sea. HCB level was lowest in polar bears from Svalbard. Polar bears from Chukchi Sea had the highest level of ??- and ??-HCH. The lowest ??-HCH concentration was found in bears from Kara Sea. In all the bears, ???HCHs was dominated by ??-HCH. The geographical variation in OCP levels and pattern may suggest regional differences in pollution sources and different feeding habits in the different regions. Polar bears from the Western Russian Arctic were exposed to higher levels of chlordanes and p,p???-DDE than polar bears from locations westwards and eastwards from this region. This may imply the presence of a significant pollution source in the Russian Arctic area. The study suggests that the western Russian Arctic is the most contaminated region of the Arctic and warrants further research. ?? 2002 Elsevier Science B.V. All rights reserved.

  7. A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme

    Directory of Open Access Journals (Sweden)

    Dennis D. Eberl

    2013-02-01

    Full Text Available This paper re-evaluates how well quantitative x-ray diffraction (qXRD can be used as an exploratory method of the weight percentage (wt% of volcaniclastic sediment, and to identify tephra events in marine cores. In the widely used RockJock v6 software programme, qXRD tephra and glass standards include the rhyodacite White River tephra (Alaska, a rhyolitic tephra (Hekla-4 and the basaltic Saksunarvatn tephra. Experiments of adding known wt% of tephra to felsic bedrock samples indicated that additions ≥10 wt% are accurately detected, but reliable estimates of lesser amounts are masked by amorphous material produced by milling. Volcaniclastic inputs range between 20 and 50 wt%. Primary tephra events are identified as peaks in residual qXRD glass wt% from fourth-order polynomial fits. In cores where tephras have been identified by shard counts in the >150 µm fraction, there is a positive correlation (validation with peaks in the wt% glass estimated by qXRD. Geochemistry of tephra shards confirms the presence of several Hekla-sourced tephras in cores B997-317PC1 and -319PC2 on the northern Iceland shelf. In core B997-338 (north-west Iceland, there are two rhyolitic tephras separated by ca. 100 cm with uncorrected radiocarbon dates on articulated shells of around 13 000 yr B.P. These tephras may be correlatives of the Borrobol and Penifiler tephras found in Scotland. The number of Holocene tephra events per 1000 yr was estimated from qXRD on 16 cores and showed a bimodal distribution with an increased number of events in both the late and early Holocene.

  8. Zooplankton in the Arctic outflow

    Science.gov (United States)

    Soloviev, K. A.; Dritz, A. V.; Nikishina, A. B.

    2009-04-01

    Climate changes in the Arctic cause the changes in the current system that may have cascading effect on the structure of plankton community and consequently on the interlinked and delicately balanced food web. Zooplankton species are by definition incapable to perform horizontal moving. Their transport is connected with flowing water. There are zooplankton species specific for the definite water masses and they can be used as markers for the different currents. That allows us to consider zooplankton community composition as a result of water mixing in the studied area. Little is known however about the mechanisms by which spatial and temporal variability in advection affect dynamics of local populations. Ice conditions are also very important in the function of pelagic communities. Melting time is the trigger to all "plankton blooming" processes, and the duration of ice-free conditions determines the food web development in the future. Fram Strait is one of the key regions for the Arctic: the cold water outflow comes through it with the East Greenland Current and meets warm Atlantic water, the West Spitsbergen Current, producing complicated hydrological situation. During 2007 and 2008 we investigated the structure functional characteristics of zooplankton community in the Fram Strait region onboard KV "Svalbard" (April 2007, April and May 2008) and RV "Jan Mayen" (May 2007, August 2008). This study was conducted in frame of iAOOS Norway project "Closing the loop", which, in turn, was a part of IPY. During this cruises multidisciplinary investigations were performed, including sea-ice observations, CTD and ADCP profiling, carbon flux, nutrients and primary production measurements, phytoplankton sampling. Zooplankton was collected with the Hydro-Bios WP2 net and MultiNet Zooplankton Sampler, (mouth area 0.25 m2, mesh size 180 um).Samples were taken from the depth strata of 2000-1500, 1500-1000, 1000-500,500-200, 200-100, 100-60, 60-30, 30-0 m. Gut fluorescence

  9. Large cryoconite aggregates on a Svalbard glacier support a diverse microbial community including ammonia-oxidizing archaea

    Science.gov (United States)

    Zarsky, Jakub D.; Stibal, Marek; Hodson, Andy; Sattler, Birgit; Schostag, Morten; Hansen, Lars H.; Jacobsen, Carsten S.; Psenner, Roland

    2013-09-01

    The aggregation of surface debris particles on melting glaciers into larger units (cryoconite) provides microenvironments for various microorganisms and metabolic processes. Here we investigate the microbial community on the surface of Aldegondabreen, a valley glacier in Svalbard which is supplied with carbon and nutrients from different sources across its surface, including colonies of seabirds. We used a combination of geochemical analysis (of surface debris, ice and meltwater), quantitative polymerase chain reactions (targeting the 16S ribosomal ribonucleic acid and amoA genes), pyrosequencing and multivariate statistical analysis to suggest possible factors driving the ecology of prokaryotic microbes on the surface of Aldegondabreen and their potential role in nitrogen cycling. The combination of high nutrient input with subsidy from the bird colonies, supraglacial meltwater flow and the presence of fine, clay-like particles supports the formation of centimetre-scale cryoconite aggregates in some areas of the glacier surface. We show that a diverse microbial community is present, dominated by the cyanobacteria, Proteobacteria, Bacteroidetes, and Actinobacteria, that are well-known in supraglacial environments. Importantly, ammonia-oxidizing archaea were detected in the aggregates for the first time on an Arctic glacier.

  10. 800 year ice-core record of nitrogen deposition in Svalbard linked to ocean productivity and biogenic emissions

    Directory of Open Access Journals (Sweden)

    I. A. Wendl

    2014-09-01

    Full Text Available We present the records of the two nitrogen species nitrate (NO3− and ammonium (NH4+ analysed in a new ice core from Lomonosovfonna, Svalbard, in the Eurasian Arctic covering the period 1222–2009. We investigate the emission sources and the influence of melt on the records. During the 20th century both records are influenced by anthropogenic pollution from Eurasia. In pre-industrial times NO3− is highly correlated with methane-sulfonate (MSA on decadal time-scales, which we explain by a fertilising effect. Enhanced atmospheric NO3− concentrations and the corresponding nitrogen input to the ocean trigger the growth of dimethyl-sulfide-(DMS-producing phytoplankton. Increased DMS production results in elevated fluxes to the atmosphere where it is oxidised to MSA. Eurasia was presumably the main source area also for pre-industrial NO3−, but a more exact source apportionment could not be performed based on our data. This is different for NH4+, where biogenic ammonia (NH3 emissions from Siberian boreal forests were identified as the dominant source of pre-industrial NH4+. Changes in melt at the Lomonosovfonna glacier are excluded as major driving force for the decadal variations of the investigated compounds.

  11. Mesozooplankton community development at elevated CO2 concentrations: results from a mesocosm experiment in an Arctic fjord

    Directory of Open Access Journals (Sweden)

    B. Niehoff

    2013-03-01

    Full Text Available The increasing CO2 concentration in the atmosphere caused by burning fossil fuels leads to increasing pCO2 and decreasing pH in the world ocean. These changes may have severe consequences for marine biota, especially in cold-water ecosystems due to higher solubility of CO2. However, studies on the response of mesozooplankton communities to elevated CO2 are still lacking. In order to test whether abundance and taxonomic composition change with pCO2, we have sampled nine mesocosms, which were deployed in Kongsfjorden, an Arctic fjord at Svalbard, and were adjusted to eight CO2 concentrations, initially ranging from 185 μatm to 1420 μatm. Vertical net hauls were taken weekly over about one month with an Apstein net (55 μm mesh size in all mesocosms and the surrounding fjord. In addition, sediment trap samples, taken every second day in the mesocosms, were analysed to account for losses due to vertical migration and mortality. The taxonomic analysis revealed that meroplanktonic larvae (Cirripedia, Polychaeta, Bivalvia, Gastropoda, and Decapoda dominated in the mesocosms while copepods (Calanus spp., Oithona similis, Acartia longiremis and Microsetella norvegica were found in lower abundances. In the fjord copepods prevailed for most of our study. With time, abundance and taxonomic composition developed similarly in all mesocosms and the pCO2 had no significant effect on the overall community structure. Also, we did not find significant relationships between the pCO2 level and the abundance of single taxa. Changes in heterogeneous communities are, however, difficult to detect, and the exposure to elevated pCO2 was relatively short. We therefore suggest that future mesocosm experiments should be run for longer periods.

  12. Arctic microbial community dynamics influenced by elevated CO2 levels

    Science.gov (United States)

    Brussaard, C. P. D.; Noordeloos, A. A. M.; Witte, H.; Collenteur, M. C. J.; Schulz, K.; Ludwig, A.; Riebesell, U.

    2013-02-01

    The Arctic Ocean ecosystem is particularly vulnerable to ocean acidification (OA) related alterations due to the relatively high CO2 solubility and low carbonate saturation states of its cold surface waters. Thus far, however, there is only little known about the consequences of OA on the base of the food web. In a mesocosm CO2-enrichment experiment (overall CO2 levels ranged from ~ 180 to 1100 μatm) in Kongsfjorden off Svalbard, we studied the consequences of OA on a natural pelagic microbial community. OA distinctly affected the composition and growth of the Arctic phytoplankton community, i.e. the picoeukaryotic photoautotrophs and to a lesser extent the nanophytoplankton thrived. A shift towards the smallest phytoplankton as a result of OA will have direct consequences for the structure and functioning of the pelagic food web and thus for the biogeochemical cycles. Besides being grazed, the dominant pico- and nanophytoplankton groups were found prone to viral lysis, thereby shunting the carbon accumulation in living organisms into the dissolved pools of organic carbon and subsequently affecting the efficiency of the biological pump in these Arctic waters.

  13. Arctic microbial community dynamics influenced by elevated CO2 levels

    Directory of Open Access Journals (Sweden)

    K. Schulz

    2012-09-01

    Full Text Available The Arctic Ocean ecosystem is particular vulnerable for ocean acidification (OA related alterations due to the relatively high CO2 solubility and low carbonate saturation states of its cold surface waters. Thus far, however, there is only little known about the consequences of OA on the base of the food web. In a mesocosm CO2-enrichment experiment (overall CO2 levels ranged from ∼180 to 1100 μatm in the Kongsfjord off Svalbard, we studied the consequences of OA on a natural pelagic microbial community. The most prominent finding of our study is the profound effect of OA on the composition and growth of the Arctic phytoplankton community, i.e. the picoeukaryotic photoautotrophs and to a lesser extent the nanophytoplankton prospered. A shift towards the smallest phytoplankton as a result of OA will have direct consequences for the structure and functioning of the pelagic food web and thus for the biogeochemical cycles. Furthermore, the dominant pico- and nanophytoplankton groups were found prone to viral lysis, thereby shunting the carbon accumulation in living organisms into the dissolved pools of organic carbon and subsequently affecting the efficiency of the biological pump in these Arctic waters.

  14. Anthropogenic radionuclides in the Arctic Ocean. Distribution and pathways

    International Nuclear Information System (INIS)

    Anthropogenic radionuclide concentrations have been determined in seawater and sediment samples collected in 1991, 1994 and 1996 in the Eurasian Arctic shelf and interior. Global fallout, releases from European reprocessing plants and the Chernobyl accident are identified as the three main sources. From measurements in the Eurasian shelf seas it is concluded that the total input of 134Cs, 137Cs and 90Sr from these sources has been decreasing during the 1990's, while 129I has increased. The main fraction of the reprocessing and Chernobyl activity found in Arctic Ocean surface layer is transported from the Barents Sea east along the Eurasian Arctic shelf seas to the Laptev Sea before entering the Nansen Basin. This inflow results in highest 137Cs, 129I and 90Sr concentrations in the Arctic Ocean surface layers, and continuously decreasing concentrations with depth. Chernobyl-derived 137Cs appeared in the central parts of the Arctic Ocean around 1991, and in the mid 1990's the fraction to total 137Cs was approximately 30% in the entire Eurasian Arctic region. The transfer times for releases from Sellafield are estimated to be 5-7 years to the SE Barents Sea, 7-9 years to the Kara Sea, 10-11 years to the Laptev Sea and 12-14 years to the central Arctic Ocean. Global fallout is the primary source of plutonium with highest concentrations found in the Atlantic layer of the Arctic Ocean. When transported over the shallow shelf seas, particle reactive transuranic elements experience an intense scavenging. A rough estimate shows that approximately 75% of the plutonium entering the Kara and Laptev Seas are removed to the sediment. High seasonal riverine input of 239, 240Pu is observed near the mouths of the large Russian rivers. Sediment inventories show much higher concentrations on the shelf compared to the deep Arctic Ocean. This is primarily due to the low particle flux in the open ocean

  15. N-ICE2015: Multi-disciplinary study of the young sea ice system north of Svalbard from winter to summer.

    Science.gov (United States)

    Steen, Harald; Granskog, Mats; Assmy, Philipp; Duarte, Pedro; Hudson, Stephen; Gerland, Sebastian; Spreen, Gunnar; Smedsrud, Lars H.

    2016-04-01

    The Arctic Ocean is shifting to a new regime with a thinner and smaller sea-ice area cover. Until now, winter sea ice extent has changed less than during summer, as the heat loss to the atmosphere during autumn and winter is large enough form an ice cover in most regions. The insulating snow cover also heavily influences the winter ice growth. Consequently, the older, thicker multi-year sea ice has been replace by a younger and thinner sea. These large changes in the sea ice cover may have dramatic consequences for ecosystems, energy fluxes and ultimately atmospheric circulation and the Northern Hemisphere climate. To study the effects of the changing Arctic the Norwegian Polar Institute, together with national and international partners, launched from January 11 to June 24, 2015 the Norwegian Young Sea ICE cruise 2015 (N-ICE2015). N-ICE2015 was a multi-disciplinary cruise aimed at simultaneously studying the effect of the Arctic Ocean changes in the sea ice, the atmosphere, in radiation, in ecosystems. as well as water chemistry. R/V Lance was frozen into the drift ice north of Svalbard at about N83 E25 and drifted passively southwards with the ice until she was broken loose. When she was loose, R/V Lance was brought back north to a similar starting position. While fast in the ice, she served as a living and working platform for 100 scientist and engineers from 11 countries. One aim of N-ICE2015 is to present a comprehensive data-set on the first year ice dominated system available for the scientific community describing the state and changes of the Arctic sea ice system from freezing to melt. Analyzing the data is progressing and some first results will be presented.

  16. Polychlorinated biphenyls and reproductive hormones in female polar bears at Svalbard.

    OpenAIRE

    Haave, Marte; Ropstad, Erik; Derocher, Andrew E; Lie, Elisabeth; Dahl, Ellen; Wiig, Øystein; Skaare, Janneche U; Jenssen, Bjørn Munro

    2003-01-01

    High concentrations of polychlorinated biphenyls (PCBs) in polar bears from Svalbard have increased concern for that population's reproductive health. We examined whether there were associations between the plasma concentrations of PCBs and reproductive hormones [progesterone (P4)] and 17 beta-estradiol (E2)] in free-living female polar bears from Svalbard. Concentrations of P4 depended on reproductive status, and concentrations were lowest in females with offspring--females with cubs and fem...

  17. The drainage pattern of Hansbreen and Werenskioldbreen, two polythermal glaciers in Svalbard

    OpenAIRE

    Pälli, Anja; Moore, John C.; Jania, Jacek; Kolondra, Leszek; Glowacki, Piotr

    2003-01-01

    To improve our understanding of Svalbard-type polythermal glacier drainage, hydraulic geometry models of the subglacial hydrology of two contrasting glaciers in Svalbard have been constructed. The models are tested against a uniquely long and rich set of field observations spanning 45 years. Digital elevation models (DEMs) were constructed from bedrock data measured with ground penetrating radar and surface data of two medium-sized polythermal glaciers, Hansbreen and Werenskioldbreen, in sout...

  18. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  19. Naturressursene og verdenspolitikken på Svalbard 1596-2011

    Directory of Open Access Journals (Sweden)

    Roald Berg

    2012-05-01

    Full Text Available The history of Spitsbergen/Svalbard has been characterized by a combination of masculine heroism and continuous struggle for the natural resources at the islands. In the beginning, from the 16th century, it was an international struggle for the harvesting of the whale and walrus; its value was so great that international conflicts led to the development of such doctrines as mare clausum and mare liberum ininternational law. The competition for the utilization of the coal resources led the Americans near annexation during the first decade of the 20th century before Norway received sovereignty over the islands after the first world war and the services of the Norwegian merchant fleet during that war. After the cold war the oil deposits in the Barents Sea might trigger another period of resource struggle at the islands and the oceans around them.

  20. Arctic River Mobility: A Baseline Assessment

    Science.gov (United States)

    Rowland, J. C.; Wilson, C. J.; Brumby, S. P.; Pope, P. A.

    2009-12-01

    and river migration in these permafrost dominated reaches. The sensitivity of niching and the collapse of undercut banks to global climate change remains an open question. Field observations and analysis of high-resolution satellite images along the Yukon Flats also suggest that despite dramatic local effects, such as debris jams, the May 2009 ice jam-related flooding along the Yukon had little detectable impact on river bank erosion. While our analysis does not show a detectable response of arctic rivers to observed changes in Arctic air temperatures, the extremely low mobility rates observed suggest that even small changes in bank erosion and meandering rates, if system-wide, would have a dramatic impact of sediment loading to arctic rivers and the relative exchange of sediment and organics between rivers and floodplains.

  1. Rising Arctic Ocean temperatures cause gas hydrate destabilization and ocean acidification

    OpenAIRE

    Biastoch, Arne; Treude, Tina; Rüpke, Lars H.; Riebesell, Ulf; Roth, Christina; Burwicz, Ewa B.; Park, Wonsun; Latif, Mojib; Böning, Claus W.; Madec, Gurvan; Wallmann, Klaus

    2011-01-01

    Formed under low temperature – high pressure conditions vast amounts of methane hydrates are considered to be locked up in sediments of continental margins including the Arctic shelf regions[1-3]. Because the Arctic has warmed considerably during the recent decades and because climate models predict accelerated warming if global greenhouse gas emissions continue to rise [3], it is debated whether shallow Arctic hydrate deposits could be destabilized in the near future[4, 5]. Me...

  2. Deep Arctic Ocean warming during the last glacial cycle

    Science.gov (United States)

    Cronin, T. M.; Dwyer, G.S.; Farmer, J.; Bauch, H.A.; Spielhagen, R.F.; Jakobsson, M.; Nilsson, J.; Briggs, W.M., Jr.; Stepanova, A.

    2012-01-01

    In the Arctic Ocean, the cold and relatively fresh water beneath the sea ice is separated from the underlying warmer and saltier Atlantic Layer by a halocline. Ongoing sea ice loss and warming in the Arctic Ocean have demonstrated the instability of the halocline, with implications for further sea ice loss. The stability of the halocline through past climate variations is unclear. Here we estimate intermediate water temperatures over the past 50,000 years from the Mg/Ca and Sr/Ca values of ostracods from 31 Arctic sediment cores. From about 50 to 11 kyr ago, the central Arctic Basin from 1,000 to 2,500 m was occupied by a water mass we call Glacial Arctic Intermediate Water. This water mass was 1–2 °C warmer than modern Arctic Intermediate Water, with temperatures peaking during or just before millennial-scale Heinrich cold events and the Younger Dryas cold interval. We use numerical modelling to show that the intermediate depth warming could result from the expected decrease in the flux of fresh water to the Arctic Ocean during glacial conditions, which would cause the halocline to deepen and push the warm Atlantic Layer into intermediate depths. Although not modelled, the reduced formation of cold, deep waters due to the exposure of the Arctic continental shelf could also contribute to the intermediate depth warming.

  3. Distinct summer and winter bacterial communities in the active layer of Svalbard permafrost revealed by DNA- and RNA-based analyses

    DEFF Research Database (Denmark)

    Schostag, Morten; Stibal, Marek; Jacobsen, Carsten S.; Bælum, Jacob; Tas, Neslihan; Elberling, Bo; Jansson, Janet K.; Semenchuk, Philipp; Prieme, Anders

    2015-01-01

    The active layer of soil overlaying permafrost in the Arctic is subjected to dramatic annual changes in temperature and soil chemistry, which likely affect bacterial activity and community structure. We studied seasonal variations in the bacterial community of active layer soil from Svalbard (78º...... phototrophic organisms (up to 48% in June) illustrating the potential importance of nitrogen fixation in otherwise nitrogen poor Arctic ecosystems and of phototrophic bacterial activity on the soil surface.......N) by co-extracting DNA and RNA from 12 soil cores collected monthly over a year. PCR amplicons of 16S rRNA genes (DNA) and reverse transcribed transcripts (cDNA) were quantified and sequenced to test for the effect of low winter temperature and seasonal variation in concentration of easily degradable...... significantly correlated with pH and dissolved organic carbon, while the potentially active (RNA-based) community structure was not significantly correlated with any of the measured soil parameters. A large fraction of the 16S rRNA transcripts was assigned to nitrogen-fixing bacteria (up to 24% in June) and...

  4. Aerosol absorption coefficient and Equivalent Black Carbon by parallel operation of AE31 and AE33 aethalometers at the Zeppelin station, Ny Ålesund, Svalbard

    Science.gov (United States)

    Eleftheriadis, Konstantinos; Kalogridis, Athina-Cerise; Vratolis, Sterios; Fiebig, Markus

    2016-04-01

    Light absorbing carbon in atmospheric aerosol plays a critical role in radiative forcing and climate change. Despite the long term measurements across the Arctic, comparing data obtained by a variety of methods across stations requires caution. A method for extracting the aerosol absorption coefficient from data obtained over the decades by filter based instrument is still under development. An IASOA Aerosol working group has been initiated to address this and other cross-site aerosol comparison opportunities. Continuous ambient measurements of EBC/light attenuation by means of a Magee Sci. AE-31 aethalometer operating at the Zeppelinfjellet station (474 m asl; 78°54'N, 11°53'E), Ny Ålesund, Svalbard, have been available since 2001 (Eleftheriadis et al, 2009), while a new aethalometer model (AE33, Drinovec et al, 2014) has been installed to operate in parallel from the same inlet since June 2015. Measurements are recorded by a Labview routine collecting all available parameters reported by the two instrument via RS232 protocol. Data are reported at 1 and 10 minute intervals as averages for EBC (μg m-3) and aerosol absorption coefficients (Mm-1) by means of routine designed to report Near Real Time NRT data at the EBAS WDCA database (ebas.nilu.no) Results for the first 6 month period are reported here in an attempt to evaluate comparative performance of the two instruments in terms of their response with respect to the variable aerosol load of light absorbing carbon during the warm and cold seasons found in the high arctic. The application of available conversion schemes for obtaining the absorption coefficient by the two instruments is found to demonstrate a marked difference in their output. During clean periods of low aerosol load (EBC loads (400loading compensation, Atmos. Meas. Tech., 8, 1965-1979, doi:10.5194/amt-8-1965-2015, 2015. Eleftheriadis, K., Vratolis, S., and Nyeki, S.: Aerosol black carbon in the European Arctic: Measurements at Zeppelin station

  5. Sedimentological characteristics of ice-wedge polygon terrain in Adventdalen (Svalbard. Environmental and climatic implications for the Late Holocene

    Directory of Open Access Journals (Sweden)

    M. Oliva

    2014-05-01

    Full Text Available Ice-wedges are widespread periglacial features in the landscape of Adventalen, Svalbard. The networks of ice-wedges have created areas with well-developed polygonal terrains in the lowest fluvial terraces in this valley. We have examined the sedimentological characteristics of the northern and southern banks of the Advent river for palaeoenvironmental purposes. The base of two sedimentary sections reported radiocarbon dates of 3.3 and 3.9 ka cal BP, respectively. The northern site is constituted by three very different lithostratigraphical units, which suggests that their formation should be related to different environmental and climate conditions. By contrast, the southern section shows a rather homogeneous composition, with no significant variations in grain size and organic matter content. In both cases the uppermost sediments are constituted by a thick aeolian deposit. According to our data, warmer climate conditions may have prevailed during the Mid Holocene until 3.3 ka cal BP with widespread peat formation in the valley bottom. Subsequently, a period with alternating soil formation and aeolian sedimentation took place from 3 to 2.5 ka cal BP, probably due to increasing climatic severity. During the last millennium a long-term cooling trend has favoured aeolian deposition in the lowest Adventalen valley.

  6. Applying multivariate analysis as decision tool for evaluating sediment-specific remediation strategies

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Lejon, Tore; Jensen, Pernille Erland;

    2016-01-01

    Multivariate methodology was employed for finding optimum remediation conditions for electrodialytic remediation of harbour sediment from an Arctic location in Norway. The parts of the experimental domain in which both sediment- and technology-specific remediation objectives were met were...

  7. Radiocaesium (137Cs) in marine mammals from Svalbard, the Barents Sea and the North Greenland Sea

    International Nuclear Information System (INIS)

    Specific activities of the anthropogenic radionuclide, 137Cs, were determined in marine mammals from Svalbard and the Barents and North Greenland Seas. Muscle samples were collected from 12 polar bears, 15 ringed seals, 10 hooded seals, 7 bearded seals, 14 harp seals, one walrus, one white whale and one blue whale in the period 2000-2003. The mean concentrations (± SD) of 137Cs were: 0.72 ± 0.62 Bq/kg wet weight (w.w.) for polar bears; 0.49 ± 0.07 Bq/kg w.w. for ringed seals; 0.25 ± 0.10 Bq/kg w.w. for hooded seals; 0.22 ± 0.11 Bq/kg w.w. for bearded seals; 0.36 ± 0.13 Bq/kg w.w. for harp seals; 0.67 Bq/kg w.w. for the white whale sample; 0.24 Bq/kg w.w. for the blue whale; and below detection limit for the walrus. Significant differences in 137Cs specific activities between some of the species were found. Ringed seals had higher specific activities than the other seal species in the study. Bearded seals and hooded seals had similar values, which were both significantly lower than the harp seal values. The results in the present study are consistent with previous reported results, indicating low specific activities of 137Cs in Arctic marine mammals in the Barents Sea and Greenland Sea region during the last 20 years. The species specific differences found may be explained by varying diet or movement and distribution patterns between species. No age related patterns were found in specific activities for the two species (polar bears and hooded seals) for which sufficient data was available. Concentration factors (CF) of 137Cs from seawater were determined for polar bears, ringed, bearded, harp and hooded seals. Mean CF values ranged from 79 ± 32 (SD) for bearded seals sampled in 2002 to 244 ± 36 (SD) for ringed seals sampled in 2003 these CF values are higher than those reported for fish and benthic organisms in the literature, suggesting bioaccumulation of 137Cs in the marine ecosystem

  8. Radiocaesium (137Cs) in marine mammals from Svalbard, the Barents Sea and the North Greenland Sea.

    Science.gov (United States)

    Andersen, Magnus; Gwynn, Justin P; Dowdall, Mark; Kovacs, Kit M; Lydersen, Christian

    2006-06-15

    Specific activities of the anthropogenic radionuclide, 137Cs, were determined in marine mammals from Svalbard and the Barents and North Greenland Seas. Muscle samples were collected from 12 polar bears, 15 ringed seals, 10 hooded seals, 7 bearded seals, 14 harp seals, one walrus, one white whale and one blue whale in the period 2000-2003. The mean concentrations (+/-SD) of 137Cs were: 0.72+/-0.62 Bq/kg wet weight (w.w.) for polar bears; 0.49+/-0.07 Bq/kg w.w. for ringed seals; 0.25+/-0.10 Bq/kg w.w. for hooded seals; 0.22+/-0.11 Bq/kg w.w. for bearded seals; 0.36+/-0.13 Bq/kg w.w. for harp seals; 0.67 Bq/kg w.w. for the white whale sample; 0.24 Bq/kg w.w. for the blue whale; and below detection limit for the walrus. Significant differences in 137Cs specific activities between some of the species were found. Ringed seals had higher specific activities than the other seal species in the study. Bearded seals and hooded seals had similar values, which were both significantly lower than the harp seal values. The results in the present study are consistent with previous reported results, indicating low specific activities of 137Cs in Arctic marine mammals in the Barents Sea and Greenland Sea region during the last 20 years. The species specific differences found may be explained by varying diet or movement and distribution patterns between species. No age related patterns were found in specific activities for the two species (polar bears and hooded seals) for which sufficient data was available. Concentration factors (CF) of 137Cs from seawater were determined for polar bears, ringed, bearded, harp and hooded seals. Mean CF values ranged from 79+/-32 (SD) for bearded seals sampled in 2002 to 244+/-36 (SD) for ringed seals sampled in 2003 these CF values are higher than those reported for fish and benthic organisms in the literature, suggesting bioaccumulation of 137Cs in the marine ecosystem. PMID:16154620

  9. Palaeoceanographic changes in Hornsund Fjord (Spitsbergen, Svalbard) over the last millennium: new insights from ancient DNA

    Science.gov (United States)

    Pawłowska, Joanna; Zajączkowski, Marek; Łącka, Magdalena; Lejzerowicz, Franck; Esling, Philippe; Pawlowski, Jan

    2016-07-01

    This paper presents a reconstruction of climate-driven environmental changes over the last millennium in Hornsund Fjord (Svalbard), based on sedimentological and micropalaeontological records. Our palaeo-investigation was supported by an analysis of foraminiferal ancient DNA (aDNA), focusing on the non-fossilized monothalamous species. The main climatic fluctuations during the last millennium were the Medieval Warm Period (MWP, AD 1000-1600), the Little Ice Age (LIA, AD 1600-1900) and the modern warming (MW, AD 1900 to present). Our study indicates that the environmental conditions in Hornsund during the MWP and the early LIA (before ˜ AD 1800) were relatively stable. The beginning of the LIA (˜ AD 1600) was poorly evidenced by the micropalaeontological record but was well marked in the aDNA data by an increased proportion of monothalamous foraminifera, especially Bathysiphon sp. The early LIA (˜ 1600 to ˜ AD 1800) was marked by an increase in the abundance of sequences of Hippocrepinella hirudinea and Cedhagenia saltatus. In the late LIA (after ˜ AD 1800), the conditions in the fjord became glacier-proximal and were characterized by increased meltwater outflows, high sedimentation and a high calving rate. This coincided with an increase in the percentages of sequences of Micrometula sp. and Vellaria pellucidus. During the MW, the major glacier fronts retreated rapidly to the inner bays, which limited the iceberg discharge to the fjord's centre and caused a shift in the foraminiferal community that was reflected in both the fossil and aDNA records. The palaeoceanographic changes in the Hornsund fjord over the last millennium were driven mainly by the inflow of shelf-originated water masses and glacial activity. However, the environmental changes were poorly evidenced in the micropalaeontological record, but they were well documented in our aDNA data. We considerably increased the number of potential proxy species by including monothalamous foraminifera in the

  10. Large-area surveys for black carbon and other light-absorbing impurities in snow: Arctic, Antarctic, North America, China (Invited)

    Science.gov (United States)

    Warren, S. G.; Doherty, S. J.; Hegg, D.; Dang, C.; Zhang, R.; Grenfell, T. C.; Brandt, R. E.; Clarke, A. D.; Zatko, M.

    2013-12-01

    Absorption of radiation by ice is extremely weak at visible and near-UV wavelengths, so small amounts of light-absorbing impurities (LAI) in snow can dominate the absorption of sunlight at these wavelengths, reducing the albedo relative to that of pure snow and leading to earlier snowmelt. Snow samples were collected in Alaska, Canada, Greenland, Svalbard, Norway, Russia, and the Arctic Ocean, on tundra, glaciers, ice caps, sea ice, and frozen lakes, and in boreal forests. Snow was collected mostly in spring, when the entire winter snowpack was accessible for sampling. Snow was also collected at 67 sites in western North America. Expeditions from Lanzhou University obtained black carbon (BC) amounts at 84 sites in northeast and northwest China. BC was measured at 3 locations on the Antarctic Plateau, and at 5 sites on East Antarctic sea ice. The snow is melted and filtered; the filters are analyzed in a spectrophotometer. Median BC mixing ratios in snow range over 4 orders of magnitude from 0.2 ng/g in Antarctica to 1000 ng/g in northeast China. Chemical analyses, input to a receptor model, indicate that the major source of BC in most of the Arctic is biomass burning, but industrial sources dominate in Svalbard and the central Arctic Ocean. Non-BC impurities, principally brown (organic) carbon, are typically responsible for ~40% of the visible and ultraviolet absorption. In northeast China BC is the dominant LAI, but in Inner Mongolia soil dominates. When the snow surface layer melts, much of the BC is left at the top of the snowpack rather than carried away in meltwater, thus causing a positive feedback on snowmelt. This process was quantified through field studies in Greenland, Alaska, and Norway, where we found that only 10-30% of the BC is removed with meltwater. The BC content of the Arctic atmosphere has declined markedly since 1989, according to the continuous measurements of near-surface air in Canada, Alaska, and Svalbard. Correspondingly, our recent BC

  11. Methane and Other Greenhouse Gases in the Arctic - Measurements, Process Studies and Modelling (MAMM)

    Science.gov (United States)

    Pyle, J. A.; Warwick, N. J.; Cain, M.; Hayman, G.; Skiba, U.; Drewer, J.; Dinsmore, K.; George, C.; Nisbet, E. G.; Lowry, D.; Fisher, R. E.; France, J. L.; Lanoiselle, M.; Brownlow, R. B.; Allen, G.; Bower, K.; Gallagher, M. W.; Percival, C.; Illingworth, S. M.; Jones, B.; Muller, J.; O'Shea, S.; Manning, A. C.; Kozlova, E.; Manning, A. J.; Smith, M.; Anderson, D.; Bauguitte, S.

    2013-12-01

    The Arctic is a major source of atmospheric methane and other greenhouse gases, of both natural and anthropogenic origin. Arctic greenhouse gas sources need to be quantified, by strength, geographic location, character (e.g. wetlands, gas fields, hydrates), and by temporal variation (daily, seasonally and annually), and their vulnerability to change assessed. To this end, the MAMM project was commissioned as part of the UK NERC Arctic Research Programme. It involves an integrated series of measurement and modelling activities. Analysis of atmospheric gas concentrations, isotopic character, and source fluxes, are being made from both the ground and from the NERC FAAM (Facility for Airborne Atmospheric Measurements) aircraft. The measurements (historic and new) are being interpreted using a suite of models (trajectory, forward and inverse) to improve the understanding of the local/regional scale, placing the role of Arctic emissions in the context of large-scale global atmospheric change. The first measurement campaign was held in August 2012. Surface flux measurements were made at the Sodankylä research station in Finland, together with in-situ surface and aircraft measurements over a wider area. In addition to flights over the Sodankylä wetlands, the aircraft also flew out to Svalbard, Norway to investigate marine sources of methane. Further campaigns are taking place in Sweden in August and September 2013. The initial measurements have been used to infer wetland emission fluxes and confirm that Scandinavian wetlands are a major source of methane in this region (see posters by Fisher et al, O'Shea et al). The aircraft also measured a high-methane plume over the sea between mainland Norway and Svalbard, which was likely advected from mainland wetland sources (see poster by France et al). Results from the field campaigns will be presented, alongside results from the NAME model (the UK Met Office's Numerical Atmospheric dispersion Modelling Environment) to help

  12. Field program for simulation of station-keeping conditions for Arctic drilling and production vessels

    International Nuclear Information System (INIS)

    Growing interest in drilling and production operations in ice-covered waters has increased the need for information on station keeping in dynamic ice conditions. Ships can be driven off position due to ice movements that are influenced by winds and ocean currents. Knowledge of the station keeping forces would assist in designing moored or dynamically-positioned drill vessels for Arctic waters. This paper discussed a field program that was conducted on the Norwegian Coast Guard icebreaker KV Svalbard in February 2008, in the Barents Sea. The ice load monitoring project was extended to include progress through ice at very low velocities as a simulation of station keeping conditions for a new generation of Arctic drill rigs and production vessels. Existing scaling relationships were employed to relate the resistance of the Svalbard to the expected resistance of a moored vessel of defined characteristics, and for different conditions. The paper summarized the results of the field measurements. It also provided insight into how the scaling relationships were developed, and their limitations. 9 refs., 5 tabs., 6 figs

  13. Arctic Climate Tipping Points

    OpenAIRE

    Lenton, Timothy M.

    2012-01-01

    There is widespread concern that anthropogenic global warming will trigger Arctic climate tipping points. The Arctic has a long history of natural, abrupt climate changes, which together with current observations and model projections, can help us to identify which parts of the Arctic climate system might pass future tipping points. Here the climate tipping points are defined, noting that not all of them involve bifurcations leading to irreversible change. Past abrupt climate changes in the A...

  14. Arctic wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Peltola, E. [Kemijoki Oy (Finland); Holttinen, H.; Marjaniemi, M. [VTT Energy, Espoo (Finland); Tammelin, B. [Finnish Meteorological Institute, Helsinki (Finland)

    1998-12-31

    Arctic wind energy research was aimed at adapting existing wind technologies to suit the arctic climatic conditions in Lapland. Project research work included meteorological measurements, instrument development, development of a blade heating system for wind turbines, load measurements and modelling of ice induced loads on wind turbines, together with the development of operation and maintenance practices in arctic conditions. As a result the basis now exists for technically feasible and economically viable wind energy production in Lapland. New and marketable products, such as blade heating systems for wind turbines and meteorological sensors for arctic conditions, with substantial export potential, have also been developed. (orig.)

  15. Arctic wind energy

    International Nuclear Information System (INIS)

    Arctic wind energy research was aimed at adapting existing wind technologies to suit the arctic climatic conditions in Lapland. Project research work included meteorological measurements, instrument development, development of a blade heating system for wind turbines, load measurements and modelling of ice induced loads on wind turbines, together with the development of operation and maintenance practices in arctic conditions. As a result the basis now exists for technically feasible and economically viable wind energy production in Lapland. New and marketable products, such as blade heating systems for wind turbines and meteorological sensors for arctic conditions, with substantial export potential, have also been developed. (orig.)

  16. Determination of Leaf Area Index, Total Foliar N, and Normalized Difference Vegetation Index for Arctic Ecosystems Dominated by Cassiope tetragona

    DEFF Research Database (Denmark)

    Campioli, M; Street, LE; Michelsen, Anders; Shaver, GR; Maere, T; Samson, R; Lemeur, R

    2009-01-01

    Leaf area index (LAI) and total foliar nitrogen (TFN) are important canopy characteristics and crucial variables needed to simulate photosynthesis and ecosystem CO2 fluxes. Although plant communities dominated by Cassiope tetragona are widespread in the Arctic, LAI and TFN for this vegetation type...... (Greenland and Svalbard). Leaves of C. tetragona are 2–6 mm long and closely appressed to their stems forming parallelepiped shoots. We determined the LAI of C. tetragona by measuring the area of the leaves while still attached to the stem, then doubling the resulting one-sided area. TFN was determined from...

  17. White Arctic vs. Blue Arctic: Making Choices

    Science.gov (United States)

    Pfirman, S. L.; Newton, R.; Schlosser, P.; Pomerance, R.; Tremblay, B.; Murray, M. S.; Gerrard, M.

    2015-12-01

    As the Arctic warms and shifts from icy white to watery blue and resource-rich, tension is arising between the desire to restore and sustain an ice-covered Arctic and stakeholder communities that hope to benefit from an open Arctic Ocean. If emissions of greenhouse gases to the atmosphere continue on their present trend, most of the summer sea ice cover is projected to be gone by mid-century, i.e., by the time that few if any interventions could be in place to restore it. There are many local as well as global reasons for ice restoration, including for example, preserving the Arctic's reflectivity, sustaining critical habitat, and maintaining cultural traditions. However, due to challenges in implementing interventions, it may take decades before summer sea ice would begin to return. This means that future generations would be faced with bringing sea ice back into regions where they have not experienced it before. While there is likely to be interest in taking action to restore ice for the local, regional, and global services it provides, there is also interest in the economic advancement that open access brings. Dealing with these emerging issues and new combinations of stakeholders needs new approaches - yet environmental change in the Arctic is proceeding quickly and will force the issues sooner rather than later. In this contribution we examine challenges, opportunities, and responsibilities related to exploring options for restoring Arctic sea ice and potential pathways for their implementation. Negotiating responses involves international strategic considerations including security and governance, meaning that along with local communities, state decision-makers, and commercial interests, national governments will have to play central roles. While these issues are currently playing out in the Arctic, similar tensions are also emerging in other regions.

  18. Surge dynamics in the Nathorstbreen glacier system, Svalbard

    Directory of Open Access Journals (Sweden)

    M. Sund

    2013-10-01

    Full Text Available Nathorstbreen glacier system (NGS recently experienced the largest surge in Svalbard since 1936, and is examined using spatial and temporal observations from DEM differencing, time-series of surface velocities from satellite synthetic aperture radar (SAR and other sources. The upper basins with maximum accumulation during quiescence correspond to regions of initial lowering. Initial speed-up exceeds quiescent velocities by a factor of several tens of times. This suggests that polythermal glaciers surges are initiated in the temperate area before mass is displaced downglacier. Subsequent downglacier mass displacement coincides with areas of 100–200 times increased velocities (stage 2. After > 5 yr the joint NGS terminus advanced abruptly into tidewater during winter. The advance was followed by upglacier propagation of crevasses, indicating a re-action following from the already displaced mass and extending flow. NGS advanced ca. 15 km, while another ca. 3 km length was lost due to calving. Surface lowering of ca. 50 m was observed in some upglacier areas and during 5 yr the total area increased by 20%. Maximum measured flow rates were at least 25 m d−1, 2500 times quiescence, while average velocities were about 10 m d−1. The surges of Zawadzkibreen cycle with ca. 70 yr periods.

  19. Surge dynamics in the Nathorstbreen glacier system, Svalbard

    Science.gov (United States)

    Sund, M.; Lauknes, T. R.; Eiken, T.

    2014-04-01

    Nathorstbreen glacier system (NGS) recently experienced the largest surge in Svalbard since 1936, and this was examined using spatial and temporal observations from DEM differencing, time series of surface velocities from satellite synthetic aperture radar (SAR) and other sources. The upper basins with maximum accumulation during quiescence corresponded to regions of initial lowering. Initial speed-up exceeded quiescent velocities by a factor of several tens. This suggests that polythermal glacier surges are initiated in the temperate area before mass is displaced downglacier. Subsequent downglacier mass displacement coincided with areas where glacier velocity increased by a factor of 100-200 times (stage 2). After more than 5 years, the joint NGS terminus advanced abruptly into the fjord during winter, increasing velocities even more. The advance was followed by up-glacier propagation of crevasses, indicating the middle and subsequently the upper part of the glaciers reacting to the mass displacement. NGS advanced ~15 km, while another ~3 km length was lost due to calving. Surface lowering of ~50 m was observed in some up-glacier areas, and in 5 years the total glacier area increased by 20%. Maximum measured flow rates were at least 25 m d-1, 2500 times quiescent velocity, while average velocities were about 10 m d-1. The surges of Zawadzkibreen cycle with ca. 70-year periods.

  20. Geophysical investigations of the methane reservoir and gas escape mechanisms on the west Svalbard margin

    Science.gov (United States)

    Minshull, T. A.; Westbrook, G. K.; Sinha, M. C.; Weitemeyer, K. A.; Henstock, T.; Chabert, A.; Vardy, M. E.; Sarkar, S.; Goswami, B.; Marsset, B.; Ker, S.; Thomas, Y.; Best, A. I.; Rajan, A.

    2012-12-01

    In 2008, over 250 bubble plumes were discovered close to the landward limit of methane hydrate stability on the west Svalbard continental margin, and sampling of ocean water in the vicinity of some of these plumes showed anomalously high methane concentrations. Many of the plumes occur in the region over which the hydrate stability field has receded during the last three decades due to ocean warming and such thermal erosion of the hydrate stability field may provide a positive feedback effect in global climate change. The presence of hydrate beneath the seabed is evidenced by the presence of a widespread bottom-simulating reflector (BSR) on the lower continental slope and by direct sampling with cores. More limited plume activity was found in deeper water at pockmark features that reach several hundred metres in diameter. During cruises in 2011 and 2012, we conducted further geophysical surveys both in the region of hydrate stability field recession on the continental slope and over a large pockmark on the nearby Vestnesa Ridge sediment drift. We conducted high-resolution seismic reflection surveys using a 90 cu. in. GI gun source and a 60-m, 60-channel hydrophone streamer, and deep-towed seismic surveys using Ifremer's SYSIF vehicle and chirp sources with 220-1050 Hz and 580-2200 Hz sweeps. We recorded both the GI-gun and the lower-frequency Chirp sources on ocean bottom seismometers to determine the velocity structure with high vertical resolution at both sites. We obtained controlled source electromagnetic (CSEM) data from both sites using a deep-towed frequency domain electromagnetic source recorded at 14 seafloor receivers with orthogonal electrodes and a towed three-component electric field receiver. At the slope site, our CSEM profile extends into deep water where a BSR is present. High-resolution and Chirp seismic reflection data show evidence for the widespread presence of subsurface gas at the slope site, both within and beneath the region of hydrate

  1. Coastal lithofacies and biofacies associated with syndepositional dolomitization and silicification (Draken Formation, Upper Riphean, Svalbard)

    Science.gov (United States)

    Fairchild, I. J.; Knoll, A. H.; Swett, K.

    1991-01-01

    The Draken Formation (120-250 m) of northeast Spitsbergen (Svalbard) forms part of a thick Upper Proterozoic carbonate platform succession. It consists predominantly of intraformational dolomitic conglomerates, with excellent textural preservation. Six main lithofacies were recognized in the field: quartz sandstones, stromatolitic mats, conglomerates with silicified intraclasts, dolostone conglomerates with desiccated mudrocks, oolitic/pisolitic grainstones and fenestral dolostones. A series of five main gradational biofacies were recognized from silicified (and rare calcified) microfossils. Biofacies 1 represents low-energy subtidal benthos (erect filaments) and plankton (acritarchs and vase-shaped microfossils) whereas biofacies 2 to 5 are microbial mat assemblages (with filamentous mat-builders, and associated dwellers and washed-in plankton) ranging from basal intertidal to high intertidal/supratidal. Colour values (a measure of the lightness of the colour shade) of sawn rock samples were quantified using a Munsell chart, and exhibit a pronounced variation (means of major groups varying from 4.0 to 5.95) across the spectrum of subtidal to supratidal sediments as inferred from other criteria. The lightening in progressively more exposed sediments is related to lowering of organic carbon contents, probably mainly by oxidation. Six types of early cement have been recognized. Calcite microspar (type 1) is common as a subtidal cement in many Proterozoic formations, whereas types 2 (subtidal isopachous fringes), 3 (subtidal hardground dolomicrite) and 4 (intertidal meniscus dolomicrite) are very similar to Phanerozoic examples except for their dolomitic mineralogy. Types 5 and 6 are complex and variable dolomite growths associated with expansion and replacive phenomena. They characterize the fenestral lithofacies and compare with modern supratidal cements. Consideration of diagenetic fabrics and truncation textures of intraclasts indicates that leaching

  2. Arctic-COLORS (Coastal Land Ocean Interactions in the Arctic) - a NASA field campaign scoping study to examine land-ocean interactions in the Arctic

    Science.gov (United States)

    Hernes, P.; Tzortziou, M.; Salisbury, J.; Mannino, A.; Matrai, P.; Friedrichs, M. A.; Del Castillo, C. E.

    2014-12-01

    The Arctic region is warming faster than anywhere else on the planet, triggering rapid social and economic changes and impacting both terrestrial and marine ecosystems. Yet our understanding of critical processes and interactions along the Arctic land-ocean interface is limited. Arctic-COLORS is a Field Campaign Scoping Study funded by NASA's Ocean Biology and Biogeochemistry Program that aims to improve understanding and prediction of land-ocean interactions in a rapidly changing Arctic coastal zone, and assess vulnerability, response, feedbacks and resilience of coastal ecosystems, communities and natural resources to current and future pressures. Specific science objectives include: - Quantify lateral fluxes to the arctic inner shelf from (i) rivers and (ii) the outer shelf/basin that affect biology, biodiversity, biogeochemistry (i.e. organic matter, nutrients, suspended sediment), and the processing rates of these constituents in coastal waters. - Evaluate the impact of the thawing of Arctic permafrost within the river basins on coastal biology, biodiversity and biogeochemistry, including various rates of community production and the role these may play in the health of regional economies. - Assess the impact of changing Arctic landfast ice and coastal sea ice dynamics. - Establish a baseline for comparison to future change, and use state-of-the-art models to assess impacts of environmental change on coastal biology, biodiversity and biogeochemistry. A key component of Arctic-COLORS will be the integration of satellite and field observations with coupled physical-biogeochemical models for predicting impacts of future pressures on Arctic, coastal ocean, biological processes and biogeochemical cycles. Through interagency and international collaborations, and through the organization of dedicated workshops, town hall meetings and presentations at international conferences, the scoping study engages the broader scientific community and invites participation of

  3. Regional variation of sediment load of Asian rivers flowing into the ocean

    Institute of Scientific and Technical Information of China (English)

    刘曙光; 丁坚; 华棣; 杨洪林; 李从先; 杨守业

    2001-01-01

    Study of Asian major rivers discharge to the ocean reveals variations of their water discharges and sediment loads, and local characteristic of river sediment concentrations. On the basis of this, the Asian rivers can be divided into three regions: Eurasia Arctic, East Asia, Southeast and South Asia Region. The Eurasia Arctic Region is characteristic of the lowest sediment concentration and load, while the East Asia Region is of the highest sediment concentration and higher sediment load, and the Southeast and South Asia Region yields higher sediment concentration and highest sediment load.

  4. Episodic fresh surface waters in the Eocene Arctic Ocean

    Science.gov (United States)

    Brinkhuis, Henk; Schouten, Stefan; Collinson, Margaret E.; Sluijs, Appy; Damsté, Jaap S. Sinninghe; Dickens, Gerald R.; Huber, Matthew; Cronin, Thomas M.; Onodera, Jonaotaro; Takahashi, Kozo; Bujak, Jonathan P.; Stein, Ruediger; van der Burgh, Johan; Eldrett, James S.; Harding, Ian C.; Lotter, André F.; Sangiorgi, Francesca; Cittert, Han Van Konijnenburg-Van; de Leeuw, Jan W.; Matthiessen, Jens; Backman, Jan; Moran, Kathryn; Expedition 302 Scientists

    2006-06-01

    It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain oceanic conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring Expedition, showing that large quantities of the free-floating fern Azolla grew and reproduced in the Arctic Ocean by the onset of the middle Eocene epoch (~50Myr ago). The Azolla and accompanying abundant freshwater organic and siliceous microfossils indicate an episodic freshening of Arctic surface waters during an ~800,000-year interval. The abundant remains of Azolla that characterize basal middle Eocene marine deposits of all Nordic seas probably represent transported assemblages resulting from freshwater spills from the Arctic Ocean that reached as far south as the North Sea. The termination of the Azolla phase in the Arctic coincides with a local sea surface temperature rise from ~10°C to 13°C, pointing to simultaneous increases in salt and heat supply owing to the influx of waters from adjacent oceans. We suggest that onset and termination of the Azolla phase depended on the degree of oceanic exchange between Arctic Ocean and adjacent seas.

  5. Mapping Snowfields in the High Arctic by UAV

    Science.gov (United States)

    Klump, Jens; Leya, Thomas; Fuhr, Günter

    2014-05-01

    Plant habitats are often influenced by small scale factors of substrate composition, topography and water sources that influence the availability of water and nutrients. In our lomg-term study to investigate the the distribution and dispersal strategies as well as the life cycle of psychrophilic algae (snow algae) it was necessary to get a better understanding of the structure of the snowfields where these algae live. Previous attempts to map snowfields using tethered platforms, such as kites or balloons, had proven to be difficult due to the very unstable weather conditions in the extreme environment of the High Arctic. The inherent problems of tethered platforms could be overcome with unmanned aerial vehicles (UAV). During the August 2013 field campaign on the Svalbard archipelago we used an Asctec Falcon 8 UAV to map snowfields and glacier surfaces in the visible and thermal infra-red spectrum. The georeferenced images were assembled into photo mosaic maps which were also converted into digital elevation models. The photo mosaic maps and digital elevation models gave new insights into small-scale factors that influence the physical and chemical conditions of the snow algae habitat. This presentation gives an overview of our results from the use of UAV for the mapping of snowfields in the High Arctic and discusses the risks and limitations of UAV in this extreme environment.

  6. Arctic Environmental Data Directory

    International Nuclear Information System (INIS)

    The Arctic Environmental Data Directory (AEDD) is being developed in cooperation with the US Global Change Research Plan. The AEDD Working Group, with members from US and Canadian agencies and academia, have described more than 300 Arctic data sets in a subset of an online data directory maintained by the US Geological Survey (USGS), ESDD (the Earth Science Data Directory). Through various links known as the Inter-operable Directory, the contents of AEDD are made available to scientists who use the NASA, NOAA, NSF and USGS data directories. Thus, scientists studying global change have access to Arctic data, and scientists studying the Arctic have access to global change data. The AEDD Working Group has sponsored development of a prototype Compact Disc Read Only Memory (CDROM) containing the indexed contents of the AEDD. Named Arctic Data Interactive (ADI), the disc was developed for use on Apple Macintosh and IBM PC-compatible computers, and uses a graphical and intuitive hypermedia user interface. The disc also contains portions of an Arctic Bibliography prepared in concert with the Polar Library Colloquy, sample full-text articles with illustrations, and selected data sets, including tabular data, text, and imagery. The ADI prototype is prepared as a model for organizing, presenting and distributing large quantities of Arctic and global change data and information to the science community. It is intended to be the first series of CDROMs with a consistent graphic design and user interface to place Arctic data and information on the desktop. The data are packaged with a powerful set of intuitive tools to navigate through and preview data sets from many disciplines and institutions. AEDD and ADI are sponsored by the Inter-agency Arctic Research Policy Committee and the Inter-agency Working Group on Data Management for Global Change, with guidance from the US Arctic Research Commission

  7. Climatic mass balance of the ice cap Vestfonna, Svalbard: A spatially distributed assessment using ERA-Interim and MODIS data

    Science.gov (United States)

    MöLler, Marco; Finkelnburg, Roman; Braun, Matthias; Hock, Regine; Jonsell, Ulf; Pohjola, Veijo A.; Scherer, Dieter; Schneider, Christoph

    2011-09-01

    The ice cap Vestfonna in the northern Svalbard archipelago is one of the largest ice bodies of the European Arctic (˜2400 km2), but little is known about its mass balance. We model the climatic mass balance of the ice cap for the period September 2000 to August 2009 on a daily basis. Ablation is calculated by a spatially distributed temperature-radiation-index melt model. Air temperature forcing is provided by ERA-Interim data that is downscaled using data from an automatic weather station operated on the ice cap. Spatially distributed net shortwave radiation fluxes are obtained from standard trigonometric techniques combined with Moderate Resolution Imaging Spectroradiometer-based cloud cover and surface albedo information. Accumulation is derived from ERA-Interim precipitation data that are bias corrected and spatially distributed as a function of elevation. Refreezing is incorporated using the Pmax approach. Results indicate that mass balance years are characterized by short ablation seasons (June to August) and correspondingly longer accumulation periods (September to May). The modeled, annual climatic mass balance rate shows an almost balanced mean of -0.02 ± 0.20 m w.e. yr-1 (meters water equivalent per year) with an associated equilibrium line altitude of 383 ± 54 m above sea level (mean ± one standard deviation). The mean winter balance is +0.32 ± 0.06 m w.e. yr-1, and the mean summer balance -0.35 ± 0.17 m w.e. yr-1. Roughly one fourth of total surface ablation is retained by refreezing indicating that refreezing is an important component of the mass budget of Vestfonna.

  8. Proposal for a Joint NASA/KSAT Ka-band RF Propagation Terminal at Svalbard, Norway

    Science.gov (United States)

    Volosin, Jeffrey; Acosta, Roberto; Nessel, James; McCarthy, Kevin; Caroglanian, Armen

    2010-01-01

    This slide presentation discusses the placement of a Ka-band RF Propagation Terminal at Svalbard, Norway. The Near Earth Network (NEN) station would be managed by Kongsberg Satellite Services (KSAT) and would benefit NASA and KSAT. There are details of the proposed NASA/KSAT campaign, and the responsibilities each would agree to. There are several reasons for the placement, a primary reason is comparison with the Alaska site, Based on climatological similarities/differences with Alaska, Svalbard site expected to have good radiometer/beacon agreement approximately 99% of time.

  9. Status and biology of ringed seals (Phoca hispida) in Svalbard

    OpenAIRE

    Christian Lydersen

    2014-01-01

    The ringed seal is the most abundant mammal in the Svalbard area. Annual pup production in this area is estimated to be 20,000. No systematic harvest records exist, but some few hundred seals are taken annually, mainly for dog food. The ringed seals in Svalbard are protected from hunting in the period 15 March - 15 April. Peak pupping season is the first week of April. New-born ringed seals weigh an average of 4.6 kg. They are nursed for about 39 days, and weaned at an average body mass of ar...

  10. Detection of Vehicle Tracks and Vegetation Damages Caused by use of Snowmobiles in the Longyearbyen Area on Svalbard using Unmanned Aircraft

    Science.gov (United States)

    Storvold, R.; Karlsen, S. R.; Solbø, S. A.; Johansen, B.; Johansen, K.; Høgda, K. A.; Tømmervik, H.; Zmarz, A.; Joly, D.

    2013-12-01

    The study area in the surroundings of Longyearbyen on Svalbard, Arctic Norway, located at 71.2°N and 16°E is characterized by dry Arctic climate with a snow season of more than eight months, annual precipitation of less than 200mm, and a mean July temperature of about 6°C. Longyearbyen is the main settlement on Svalbard, with about 2000 inhabitants. During the last two decades the number of snowmobiles have increased from a few hundred to a number almost equals the number of inhabitants, and snowmobile trips are today the one of the main leisure activities. In addition, thousands of tourist visits every spring, and many of these go on organized snowmobile trips. Due to the often thin snow cover, and use of snowmobile even during the spring snow melt in May and early June, the rapid growth in use of snowmobile has made some damage to the vegetation. Damage on the fragile vegetation caused by the skids and belts of the snowmobile can be observed in most parts of the Adventdalen valley, close to Longyearbyen. The main aim of this study is to explore the feasibility and accuracy of using data from Unmanned Aircraft Systems (UAS) to identify vehicle tracks and damages on vegetation caused by the use of snowmobiles. Use of UAS give the opportunity to carry out research in a manner that minimizes the environmental footprint of the research activities. Small unmanned aircraft, combining both fixed wing multi rotor types allow us to collect image data for vegetation mapping without having any personnel walking into the field disturbing the sensitive High Arctic ecosystems. UAS used here are inexpensive and simple to operate. They are being developed with the goal of providing airborne capabilities for scientists at an affordable cost. The aircraft were instrumented with a normal Canon Powershot S100 RGB compact camera and a modified Canon Powershot SX230 NDVI camera. The fixed wing aircraft was taking pictures from 100 meters altitude with ground resolution of 2.5 cm

  11. High diversity of root associated fungi in both alpine and arctic Dryas octopetala

    Directory of Open Access Journals (Sweden)

    Geml Jozsef

    2010-11-01

    Full Text Available Abstract Background Dryas octopetala is a widespread dwarf shrub in alpine and arctic regions that forms ectomycorrhizal (ECM symbiotic relationships with fungi. In this study we investigated the fungal communities associated with roots of D. octopetala in alpine sites in Norway and in the High Arctic on Svalbard, where we aimed to reveal whether the fungal diversity and species composition varied across the Alpine and Arctic regions. The internal transcribed spacer (ITS region of nuclear ribosomal DNA was used to identify the fungal communities from bulk root samples obtained from 24 plants. Results A total of 137 operational taxonomic units (OTUs were detected (using 97% similarity cut off during sequence clustering and well-known ECM genera such as Cenococcum, Cortinarius, Hebeloma, Inocybe and Tomentella occurred frequently. There was no decrease in fungal diversity with increasing latitude. The overall spatial heterogeneity was high, but a weak geographical structuring of the composition of OTUs in the root systems was observed. Calculated species accumulation curves did not level off. Conclusions This study indicates that the diversity of fungi associated with D. octopetala does not decrease in high latitude arctic regions, which contrasts observations made in a wide spectrum of other organism groups. A high degree of patchiness was observed across root systems, but the fungal communities were nevertheless weakly spatially structured. Non-asymptotical species accumulation curves and the occurrence of a high number of singletons indicated that only a small fraction of the fungal diversity was detected.

  12. Seismic surveys test on Innerhytta Pingo, Adventdalen, Svalbard Islands

    Science.gov (United States)

    Boaga, Jacopo; Rossi, Giuliana; Petronio, Lorenzo; Accaino, Flavio; Romeo, Roberto; Wheeler, Walter

    2015-04-01

    We present the preliminary results of an experimental full-wave seismic survey test conducted on the Innnerhytta a Pingo, located in the Adventdalen, Svalbard Islands, Norway. Several seismic surveys were adopted in order to study a Pingo inner structure, from classical reflection/refraction arrays to seismic tomography and surface waves analysis. The aim of the project IMPERVIA, funded by Italian PNRA, was the evaluation of the permafrost characteristics beneath this open-system Pingo by the use of seismic investigation, evaluating the best practice in terms of logistic deployment. The survey was done in April-May 2014: we collected 3 seismic lines with different spacing between receivers (from 2.5m to 5m), for a total length of more than 1 km. We collected data with different vertical geophones (with natural frequency of 4.5 Hz and 14 Hz) as well as with a seismic snow-streamer. We tested different seismic sources (hammer, seismic gun, fire crackers and heavy weight drop), and we verified accurately geophone coupling in order to evaluate the different responses. In such peculiar conditions we noted as fire-crackers allow the best signal to noise ratio for refraction/reflection surveys. To ensure the best geophones coupling with the frozen soil, we dug snow pits, to remove the snow-cover effect. On the other hand, for the surface wave methods, the very high velocity of the permafrost strongly limits the generation of long wavelengths both with these explosive sources as with the common sledgehammer. The only source capable of generating low frequencies was a heavy drop weight system, which allows to analyze surface wave dispersion below 10 Hz. Preliminary data analysis results evidence marked velocity inversions and strong velocity contrasts in depth. The combined use of surface and body waves highlights the presence of a heterogeneous soil deposit level beneath a thick layer of permafrost. This is the level that hosts the water circulation from depth controlling

  13. Application of a minimal glacier model to Hansbreen, Svalbard

    Directory of Open Access Journals (Sweden)

    J. Oerlemans

    2011-01-01

    Full Text Available Hansbreen is a well studied tidewater glacier in the southwestern part of Svalbard, currently about 16 km long. Since the end of the 19th century it has been retreating over a distance of 2.7 km. In this paper the global dynamics of Hansbreen are studied with a minimal glacier model, in which the ice mechanics are strongly parameterised and a simple law for iceberg calving is used. The model is calibrated by reconstructing a climate history in such a way that observed and simulated glacier length match. In addition, the calving law is tuned to reproduce the observed mean calving flux for the period 2000–2008.

    Equilibrium states are studied for a wide range of values of the equilibrium line altitude. The dynamics of the glacier are strongly nonlinear. The height-mass balance feedback and the water depth-calving flux feedback give rise to cusp catastrophes in the system.

    For the present climatic conditions Hansbreen cannot survive. Depending on the imposed climate change scenario, in AD 2100 Hansbreen is predicted to have a length between 10 and 12 km. The corresponding decrease in ice volume (relative to the volume in AD 2000 is 45 to 65%.

    Finally the late-Holocene history of Hansbreen is considered. We quote evidence from dated peat samples that Hansbreen did not exist during the Holocene Climatic Optimum. We speculate that at the end of the mid-Holocene Climatic Optimum Hansbreen could advance because the glacier bed was at least 50 m higher than today, and because the tributary glaciers on the western side may have supplied a significant amount of mass to the main stream. The excavation of the overdeepening and the formation of the shoal at the glacier terminus probably took place during the Little Ice Age.

  14. Arctic Climate Systems Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ivey, Mark D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robinson, David G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Boslough, Mark B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Backus, George A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Peterson, Kara J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); van Bloemen Waanders, Bart G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swiler, Laura Painton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Desilets, Darin Maurice [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Reinert, Rhonda Karen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    This study began with a challenge from program area managers at Sandia National Laboratories to technical staff in the energy, climate, and infrastructure security areas: apply a systems-level perspective to existing science and technology program areas in order to determine technology gaps, identify new technical capabilities at Sandia that could be applied to these areas, and identify opportunities for innovation. The Arctic was selected as one of these areas for systems level analyses, and this report documents the results. In this study, an emphasis was placed on the arctic atmosphere since Sandia has been active in atmospheric research in the Arctic since 1997. This study begins with a discussion of the challenges and benefits of analyzing the Arctic as a system. It goes on to discuss current and future needs of the defense, scientific, energy, and intelligence communities for more comprehensive data products related to the Arctic; assess the current state of atmospheric measurement resources available for the Arctic; and explain how the capabilities at Sandia National Laboratories can be used to address the identified technological, data, and modeling needs of the defense, scientific, energy, and intelligence communities for Arctic support.

  15. The Caledonian suture in the high Arctic? New data from the Chukchi Borderland, Amerasia Basin

    Science.gov (United States)

    O'Brien, T.; Brumley, K. J.; Miller, E. L.; Mayer, L. A.

    2013-12-01

    The Chukchi Borderland (CB) is a bathymetric high in the Arctic Ocean that is extended by N-S and E-W striking faults. Based on sediment cores of talus slope fragments at the base of the Northwind Ridge (NWR), basement of the CB was previously interpreted as a Paleozoic platform sequence comparable to passive margin strata of western Laurentia (Grantz et al., 1998). The discovery of Silurian (~430 Ma) orthogneiss dredged from a fault scarp in the central CB suggests instead that the CB is a displaced fragment of the Caledonian orogen (Brumley et al., 2008). U-Pb geochronology of zircon suites from rocks dredged from the NWR and central CB fault scarps help resolve the make-up of the CB basement. Samples from the central CB are believed to represent the country rocks of the previously dated Silurian orthogneiss. They consist mostly of paragneiss and lesser orthogneiss intruded by leucosomal segregations, all deformed and metamorphosed to amphibolite facies with assemblages Qtz + Kfs + Plag + Bt + Grt × Ms × Chl (retrograde) with accessory zircon, sphene and apatite. The abundance of Kfs + Plag + Bt in paragneiss samples suggest a volcanogenic sediment protolith. Dynamic recrystallization of quartz by grain-boundary migration and recrystallization/myrmekite development along the edges of feldspar crystals suggest final deformation at temperatures of ~450 C. U-Pb geochronology of zircon from an orthogneiss sample from the central CB yields an age of 499.2 × 0.9 Ma with late Neoproterozoic (600 Ma) and Mesoproterozoic - early Paleoproterozoic (1100-1700 Ma) grains. Detrital zircon geochronology from four paragneiss samples show a broad range of ages between 480-650 Ma with a dominant age peak ~500 Ma. Lesser, mostly discordant, Mesoproterozoic and Paleoproterozoic zircons are also present. The paragneiss sampled represent an arc-proximal sediment intruded by Silurian granitoids. Dredge samples from the NWR consist of deformed and metamorphosed calcareous sandstones

  16. Seasonal variations of net CO2 exchange in European Arctic ecosystems

    International Nuclear Information System (INIS)

    The carbon dioxide exchange in arctic and subarctic terrestrial ecosystems has been measured using the eddy-covariance method at sites representing the latitudinal and longitudinal extremes of the European Arctic sea areas as part of the Land Arctic Physical Processes (LAPP) project. The sites include two fen (Kaamanen and Kevo) and one mountain birch ecosystems in subarctic northern Finland (69o N); fen, heath land, and snow bed willow ecosystems in northeastern Greenland (74o N); and a polar semi desert site in Svalbard (79o N). The measurement results, which are given as weekly average diurnal cycles, show the striking seasonal development of the net CO2 fluxes. The seasonal periods important for the net CO2 fluxes, i.e. winter, thaw, pre-leaf, summer, and autumn can be identified from measurements of the physical environment, such as temperature, albedo, and greenness. During the late winter period continuous efflux is observed at the permafrost-free Kaamanen site. At the permafrost sites, efflux begins during the thaw period, which lasts about 3-5 weeks, in contrast to the Kaamanen site where efflux continues at the same rate as during the winter. Seasonal efflux maximum is during the pre-leaf period, which lasts about 2-5 weeks. The summer period lasts 6 weeks in NE Greenland but 10-14 weeks in northern Finland. During a high summer week, the mountain birch ecosystem had the highest gross photosynthetic capacity, GPmax, followed by the fen ecosystems. The polar semi desert ecosystem had the lowest GPmax. By the middle of August, noon uptake fluxes start to decrease as the solar elevation angle decreases and senescence begins within the vascular plants. At the end of the autumn period, which lasts 2-5 weeks, topsoil begins to freeze at the end of August in Svalbard; at the end of September at sites in eastern Greenland; and one month later at sites in northern Finland. (author)

  17. Isotopes in the Arctic atmospheric water cycle

    Science.gov (United States)

    Bonne, Jean-Louis; Werner, Martin; Meyer, Hanno; Kipfstuhl, Sepp; Rabe, Benjamin; Behrens, Melanie; Schönicke, Lutz; Steen Larsen, Hans Christian; Masson-Delmotte, Valérie

    2016-04-01

    measurements highlighted significant synoptic variations in summer in both sites. In Samoylov, the premises of a seasonal cycle have been observed during the summer-fall transition, with a fast humidity level and isotopic decrease. The latitudinal gradient is also highly visible on the Polarstern record. Complementing simulations of the water vapour isotopic composition by the ECHAM5-wiso model reproduce the Polarstern synoptic variability and spatial patterns with a good accuracy. In the near future, our records will be combined with simultaneous water isotope measurements in Iceland (by Hans Christian Steen-Larsen, CIC), Svalbard (by Valérie-Masson Delmotte, LSCE) and paired with complementing climate simulations enhanced by water isotope diagnostics. These data sets, covering an approx. 6,000 km transect of Northern Eurasia will allow for a quantitative assessment of the isotopic variations of the Arctic water cycle. The results of these analyses will also be of relevance for the interpretation of isotope signals found in ice cores and on terrestrial Arctic sites in terms of past climate change.

  18. Experimental icing affects growth, mortality, and flowering in a high Arctic dwarf shrub.

    Science.gov (United States)

    Milner, Jos M; Varpe, Øystein; van der Wal, René; Hansen, Brage Bremset

    2016-04-01

    Effects of climate change are predicted to be greatest at high latitudes, with more pronounced warming in winter than summer. Extreme mid-winter warm spells and heavy rain-on-snow events are already increasing in frequency in the Arctic, with implications for snow-pack and ground-ice formation. These may in turn affect key components of Arctic ecosystems. However, the fitness consequences of extreme winter weather events for tundra plants are not well understood, especially in the high Arctic. We simulated an extreme mid-winter rain-on-snow event at a field site in high Arctic Svalbard (78°N) by experimentally encasing tundra vegetation in ice. After the subsequent growing season, we measured the effects of icing on growth and fitness indices in the common tundra plant, Arctic bell-heather (Cassiope tetragona). The suitability of this species for retrospective growth analysis enabled us to compare shoot growth in pre and postmanipulation years in icing treatment and control plants, as well as shoot survival and flowering. Plants from icing treatment plots had higher shoot mortality and lower flowering success than controls. At the individual sample level, heavily flowering plants invested less in shoot growth than nonflowering plants, while shoot growth was positively related to the degree of shoot mortality. Therefore, contrary to expectation, undamaged shoots showed enhanced growth in ice treatment plants. This suggests that following damage, aboveground resources were allocated to the few remaining undamaged meristems. The enhanced shoot growth measured in our icing treatment plants has implications for climate studies based on retrospective analyses of Cassiope. As shoot growth in this species responds positively to summer warming, it also highlights a potentially complex interaction between summer and winter conditions. By documenting strong effects of icing on growth and reproduction of a widespread tundra plant, our study contributes to an understanding of

  19. The scavenging processes controlling the seasonal cycle in Arctic sulphate and black carbon aerosol

    Science.gov (United States)

    Pringle, K.; Browse, J.; Carslaw, K. S.; Arnold, S.; Boucher, O.

    2013-12-01

    The seasonal cycle in Arctic aerosol is typified by high concentrations of large aged anthropogenic particles transported from lower latitudes in the late Arctic winter and early spring followed by a sharp transition to low concentrations of locally sourced smaller particles in the summer. However, multi-model assessments show that many models fail to simulate a realistic cycle. Here, we use a global aerosol microphysics model (GLOMAP) and surface-level aerosol observations to understand how wet scavenging processes control the seasonal variation in Arctic black carbon (BC) and sulphate aerosol. We show that the transition from high wintertime concentrations to low concentrations in the summer is controlled by the transition from ice-phase cloud scavenging to the much more efficient warm cloud scavenging in the late spring troposphere. This seasonal cycle is amplified further by the appearance of warm drizzling cloud in the late spring and summer boundary layer. Implementing these processes in GLOMAP greatly improves the agreement between the model and observations at the three Arctic ground-stations Alert, Barrow and Zeppelin Mountain on Svalbard. The SO4 model-observation correlation coefficient (R) increases from: -0.33 to 0.71 at Alert (82.5N), from -0.16 to 0.70 at Point Barrow (71.0N) and from -0.42 to 0.40 at Zeppelin Mountain (78N). The BC model-observation correlation coefficient increases from -0.68 to 0.72 at Alert and from -0.42 to 0.44 at Barrow. Observations at three marginal Arctic sites (Janiskoski, Oulanka and Karasjok) indicate a far weaker aerosol seasonal cycle, which we show is consistent with the much smaller seasonal change in the frequency of ice clouds compared to higher latitude sites. Our results suggest that the seasonal cycle in Arctic aerosol is driven by temperature-dependent scavenging processes that may be susceptible to modification in a future climate.

  20. PREVALENCE OF ANTIBODIES AGAINST TOXOPLASMA GONDII IN POLAR BEARS (URSUS MARITIMUS) FROM SVALBARD AND EAST GREENLAND

    Science.gov (United States)

    Serum samples from 419 polar bears (Ursus maritimus) from Svalbard and the Barents Sea (collected 1990 - 2000) and 108 polar bears from East Greenland (collected 1999 - 2004) were assayed for antibodies against Toxoplasma gondii using the modified agglutination test (MAT). Antibody prevalences were ...

  1. The lichen genus Caloplaca (Ascomycota, Lecanoromycetes) on Svalbard. Notes and additions

    DEFF Research Database (Denmark)

    Søchting, Ulrik; Lorentsen, Line Balschmidt; Arup, Ulf

    2008-01-01

    23 species of the lichen genus Caloplaca from Svalbard are described and/or discussed. The descriptions are natural language descriptions based on characters for each species coded into LIAS (Global Information System for Lichenized and Non-Lichenized Ascomycetes). A total of 37 Caloplaca species...

  2. Terrestrial invertebrates along a gradient of deglaciation in Svalbard: Relation to microbial communities

    Czech Academy of Sciences Publication Activity Database

    Devetter, Miloslav; Bryndová, Michala; Háněl, Ladislav; Schlaghamerský, J.; Raschmanová, N.; Chroňáková, Alica

    České Budějovice: Institute of Soil Biology, BC CAS, 2015. s. 20. ISBN ISBN 978-80-86525-29-7. [Central European Workshop on Soil Zoology /13./. 13.04.2015-15.04.2015, České Budějovice] Institutional support: RVO:60077344 Keywords : terrestrial invertebrates * gradient of deglaciation * Svalbard Subject RIV: EH - Ecology, Behaviour

  3. Arctic Shipping Emissions in the Changing Climate

    OpenAIRE

    Vihanninjoki, Vesa

    2014-01-01

    Due to the Arctic climate change and the related diminishing of Arctic sea ice cover, the general conditions for Arctic shipping are changing. The retreat of Arctic sea ice opens up new routes for maritime transportation, both trans-Arctic passages and new alternatives within the Arctic region. Hence the amount of Arctic shipping is presumed to increase. Despite the observed development, the sailing conditions in the Arctic waters will remain challenging. Thus particular attention will be ...

  4. Geomagnetic palaeosecular variation around 15 ka ago from NW Barents Sea cores (south of Svalbard)

    Science.gov (United States)

    Sagnotti, Leonardo; Macrì, Patrizia; Lucchi, Renata G.

    2016-02-01

    The sedimentary sequence deposited during the deglaciation phase following the last glacial maximum in the Storfjorden trough, on the northwestern Barents Sea south of Svalbard, was sampled with 10 piston and gravity cores during the SVAIS and EGLACOM cruises. Three cores (SV-02, SV-03 and SV-05) collected on the upper continental slope are characterized by a thin (20-40 cm) Holocene interval and a thick (up to 4.5 m in core SV-03) late Pleistocene sequence of finely laminated fine-grained sediments that have been interpreted as plumites deposited during the Melt Water Pulse 1a (MWP-1a). Radiocarbon ages obtained at the top and bottom of this stratigraphic interval revealed that deposition occurred during less than two centuries at around 15 ka ago, with a very high sedimentary rate exceeding 3 cm a-1. We studied the palaeomagnetic and rock magnetic properties of this interval, by taking magnetic measurements at 1 cm spacing on u-channel samples collected from the three cores. The data show that this sequence is characterized by good palaeomagnetic properties and the palaeomagnetic and rock magnetic trends may be correlated at high resolution from core to core. The obtained palaeomagnetic data therefore offer the unique opportunity to investigate in detail the rate of geomagnetic palaeosecular variation (PSV) in the high northern latitudes at a decadal scale. Notwithstanding the palaeomagnetic trends of the three cores may be closely matched, the amplitude of directional PSV and the consequent virtual geomagnetic pole (VGP) scatter (S) is distinctly higher in one core (SV-05) than in the other two cores (SV-02 and SV-03). This might result from a variable proportion of two distinct populations of magnetic minerals in core SV-05, as suggested by the variable tendency to acquire a gyromagnetic remanent magnetization at high fields during the AF demagnetization treatment. For the plumite interval of cores SV-02 and SV-03, where the magnetic mineralogy is uniform and

  5. Arctic Bathymetry (batharcst)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The digitally compiled map includes geology, oil and gas field centerpoints, and geologic provinces of the Arctic (North Pole area encircled by 640 N Latitude). The...

  6. Live from the Arctic

    Science.gov (United States)

    Warnick, W. K.; Haines-Stiles, G.; Warburton, J.; Sunwood, K.

    2003-12-01

    For reasons of geography and geophysics, the poles of our planet, the Arctic and Antarctica, are places where climate change appears first: they are global canaries in the mine shaft. But while Antarctica (its penguins and ozone hole, for example) has been relatively well-documented in recent books, TV programs and journalism, the far North has received somewhat less attention. This project builds on and advances what has been done to date to share the people, places, and stories of the North with all Americans through multiple media, over several years. In a collaborative project between the Arctic Research Consortium of the United States (ARCUS) and PASSPORT TO KNOWLEDGE, Live from the Arctic will bring the Arctic environment to the public through a series of primetime broadcasts, live and taped programming, interactive virtual field trips, and webcasts. The five-year project will culminate during the 2007-2008 International Polar Year (IPY). Live from the Arctic will: A. Promote global understanding about the value and world -wide significance of the Arctic, B. Bring cutting-edge research to both non-formal and formal education communities, C. Provide opportunities for collaboration between arctic scientists, arctic communities, and the general public. Content will focus on the following four themes. 1. Pan-Arctic Changes and Impacts on Land (i.e. snow cover; permafrost; glaciers; hydrology; species composition, distribution, and abundance; subsistence harvesting) 2. Pan-Arctic Changes and Impacts in the Sea (i.e. salinity, temperature, currents, nutrients, sea ice, marine ecosystems (including people, marine mammals and fisheries) 3. Pan-Arctic Changes and Impacts in the Atmosphere (i.e. precipitation and evaporation; effects on humans and their communities) 4. Global Perspectives (i.e. effects on humans and communities, impacts to rest of the world) In The Earth is Faster Now, a recent collection of comments by members of indigenous arctic peoples, arctic

  7. Arctic_Bathymetry

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Models project the Arctic Ocean will become undersaturated with respect to carbonate minerals in the next decade. Recent field results indicate parts may already be...

  8. Arctic survey, 1957

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes a survey and game patrol conducted to twelve villages in the Arctic from April 24 to May 2 1957. The report covers animals take for income...

  9. Arctic Geology (geoarcst)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The digitally compiled map includes geology, oil and gas field centerpoints, and geologic provinces of the Arctic (North Pole area encircled by 640 N Latitude). The...

  10. Arctic Tourism: Realities & Possibilities

    OpenAIRE

    Pashkevich, Albina

    2014-01-01

    This paper addresses human capital in the Arctic in relation to tourism. More specifically, with an ever-increasing number oftourists recognizing the attractiveness of the Arctic, tour companies are increasingly recognizing the opportunities. The media(typically southern media) sells the image, either before or after the tourists arrive, and communities are often left to deal with therepercussions – whether those are social, economic, environmental, or the like. Many of the repercussions are ...

  11. Regional Aerosol Optical Properties and Radiative Impact of the Extreme Smoke Event in the European Arctic in Spring 2006

    Science.gov (United States)

    Lund Myhre, C.; Toledano, C.; Myhre, G.; Stebel, K.; Yttri, K.; Aaltonen, V.; Johnsrud, M.; Frioud, M.; Cachorro, V.; deFrutos, A.; Lihavainen, H.; Campbell, J.; Chaikovsky, A.; Shiobara, M.; Welton, E.; Torseth, K.

    2007-01-01

    In spring 2006 a special meteorological situation occurred in the European Arctic region giving record high levels of air pollution. The synoptic situation resulted in extensive transport of pollution predominantly from agricultural fires in Eastern Europe into the Arctic region and record high air-pollution levels were measured at the Zeppelin observatory at Ni-Alesun(78deg 54'N, 11deg 53'E) in the period from 25 April to 12 May. In the present study we investigate the optical properties of the aerosols from this extreme event and we estimate the radiative forcing of this episode. We examine the aerosol optical properties from the source region and into the European Arctic and explore the evolution of the episode and the changes in the optical properties. A number of sites in Eastern Europe, Northern Scandinavia and Svalbard are included in the study. In addition to AOD measurements, we explored lidar measurements from Minsk, ALOMAR (Arctic Lidar Observatory for Middle Atmosphere Research at Andenes) and Ny-Alesund. For the AERONET sites included (Minsk, Toravere, Hornsund) we have further studied the evolution of the aerosol size. Importantly, at Svalbard it is consistency between the AERONET measurements and calculations of single scattering albedo based on aerosol chemical composition. We have found strong agreement between the satellite dally MODIS AOD and the ground-based AOD observations. This agreement is crucial for the radiative forcing calculations. We calculate a strong negative radiative forcing for the most polluted days employing the analysed ground based data, MODIS AOD and a multi-stream model for radiative transfer of solar radiation.

  12. Regional aerosol optical properties and radiative impact of the extreme smoke event in the European Arctic in spring 2006

    Directory of Open Access Journals (Sweden)

    C. Lund Myhre

    2007-07-01

    Full Text Available In spring 2006 a special meteorological situation occurred in the European Arctic region giving record high levels of air pollution. The synoptic situation resulted in extensive transport of pollution predominantly from agricultural fires in Eastern Europe into the Arctic region and record high air-pollution levels were measured at the Zeppelin observatory at Ny-Ålesund (78°54' N, 11°53' E in the period from 25 April to 12 May. In the present study we investigate the optical properties of the aerosols from this extreme event and we estimate the radiative forcing of this episode.

    We examine the aerosol optical properties from the source region and into the European Arctic and explore the evolution of the episode and the changes in the optical properties. A number of sites in Eastern Europe, Northern Scandinavia and Svalbard are included in the study. In addition to AOD measurements, we explored lidar measurements from Minsk, ALOMAR (Arctic Lidar Observatory for Middle Atmosphere Research at Andenes and Ny-Ålesund. For the AERONET sites included (Minsk, Toravere, Hornsund we have further studied the evolution of the aerosol size. Importantly, at Svalbard it is consistency between the AERONET measurements and calculations of single scattering albedo based on aerosol chemical composition. We have found strong agreement between the satellite daily MODIS AOD and the ground-based AOD observations. This agreement is crucial for the radiative forcing calculations. We calculate a strong negative radiative forcing for the most polluted days employing the analysed ground based data, MODIS AOD and a multi-stream model for radiative transfer of solar radiation.

  13. Arctic freshwater synthesis: Introduction

    Science.gov (United States)

    Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.

    2015-11-01

    In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program, an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason for joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. Hence, the key objective of the AFSΣ was to produce an updated, comprehensive, and integrated review of the structure and function of the entire AFS. The AFSΣ was organized around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources and modeling, and the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ—Introduction reviews the motivations for, and foci of, previous studies of the AFS, discusses criteria used to define the domain of the AFS, and details key characteristics of the definition adopted for the AFSΣ.

  14. Anthropogenic radionuclides in the Arctic Ocean. Distribution and pathways

    Energy Technology Data Exchange (ETDEWEB)

    Josefsson, Dan

    1998-05-01

    Anthropogenic radionuclide concentrations have been determined in seawater and sediment samples collected in 1991, 1994 and 1996 in the Eurasian Arctic shelf and interior. Global fallout, releases from European reprocessing plants and the Chernobyl accident are identified as the three main sources. From measurements in the Eurasian shelf seas it is concluded that the total input of {sup 134}Cs, {sup 137}Cs and {sup 90}Sr from these sources has been decreasing during the 1990`s, while {sup 129}I has increased. The main fraction of the reprocessing and Chernobyl activity found in Arctic Ocean surface layer is transported from the Barents Sea east along the Eurasian Arctic shelf seas to the Laptev Sea before entering the Nansen Basin. This inflow results in highest {sup 137}Cs, {sup 129}I and {sup 90}Sr concentrations in the Arctic Ocean surface layers, and continuously decreasing concentrations with depth. Chernobyl-derived {sup 137}Cs appeared in the central parts of the Arctic Ocean around 1991, and in the mid 1990`s the fraction to total {sup 137}Cs was approximately 30% in the entire Eurasian Arctic region. The transfer times for releases from Sellafield are estimated to be 5-7 years to the SE Barents Sea, 7-9 years to the Kara Sea, 10-11 years to the Laptev Sea and 12-14 years to the central Arctic Ocean. Global fallout is the primary source of plutonium with highest concentrations found in the Atlantic layer of the Arctic Ocean. When transported over the shallow shelf seas, particle reactive transuranic elements experience an intense scavenging. A rough estimate shows that approximately 75% of the plutonium entering the Kara and Laptev Seas are removed to the sediment. High seasonal riverine input of {sup 239}, {sup 240}Pu is observed near the mouths of the large Russian rivers. Sediment inventories show much higher concentrations on the shelf compared to the deep Arctic Ocean. This is primarily due to the low particle flux in the open ocean

  15. The Arctic Visiting Speakers Program

    Science.gov (United States)

    Wiggins, H. V.; Fahnestock, J.

    2013-12-01

    The Arctic Visiting Speakers Program (AVS) is a program of the Arctic Research Consortium of the U.S. (ARCUS) and funded by the National Science Foundation. AVS provides small grants to researchers and other Arctic experts to travel and share their knowledge in communities where they might not otherwise connect. The program aims to: initiate and encourage arctic science education in communities with little exposure to arctic research; increase collaboration among the arctic research community; nurture communication between arctic researchers and community residents; and foster arctic science education at the local level. Individuals, community organizations, and academic organizations can apply to host a speaker. Speakers cover a wide range of arctic topics and can address a variety of audiences including K-12 students, graduate and undergraduate students, and the general public. Preference is given to tours that reach broad and varied audiences, especially those targeted to underserved populations. Between October 2000 and July 2013, AVS supported 114 tours spanning 9 different countries, including tours in 23 U.S. states. Tours over the past three and a half years have connected Arctic experts with over 6,600 audience members. Post-tour evaluations show that AVS consistently rates high for broadening interest and understanding of arctic issues. AVS provides a case study for how face-to-face interactions between arctic scientists and general audiences can produce high-impact results. Further information can be found at: http://www.arcus.org/arctic-visiting-speakers.

  16. Microbial Ecology at an Arctic Geothermal Spring

    Science.gov (United States)

    Starke, V.; Fogel, M. L.; Steele, A.; Arctic Mars Analog Svalbard Expedition (Amase)

    2011-12-01

    A critical question in microbial ecology concerns how variations in environmental conditions affect microbial community makeup. Arctic thermal springs provide an exceptional opportunity to study this question because they have very steep gradients in temperature, moisture, and mobility that place strong selective pressures on microorganisms. Troll Springs, located near 79°23'N, 13°26E in the Svalbard archipelago north of Norway, is one of the northernmost documented thermal springs on land. Precipitation of travertine (calcium carbonate) from Troll's carbonate-rich waters has built a complex terrace structure. Biological materials are present at all levels of the spring structure. To investigate this microbial community in detail, we analyzed DNA extracted from wet biofilms, granular samples and endoliths with 454 parallel-tagged pyrosequencing and automated ribosomal intergenic spacer analysis (ARISA). The aim is to provide a comprehensive overview of how the community at Troll Springs changes over the gradients in environmental conditions present. The 454 and ARISA data were analyzed using multivariate methods, including non-metric multidimensional scaling (nMDS). Results show a gradual transition in the makeup of the microbial community as the environment changes from aquatic to lithologic. These observations suggest a mechanism by which the rocks are colonized by microorganisms: biofilm becomes entrapped during carbonate precipitation. Use of a range of parameters and techniques in the data processing and multidimensional scaling provides additional insight into how community makeup varies across the environments present at the spring. Some more adaptable species are found across most environments, but change markedly in abundance as the conditions change. Other less adaptable species are found in fewer environments, being wholly absent in most. Continued analysis will help reveal which species are the most adaptable, and how their adaptive capabilities

  17. Distinct summer and winter bacterial communities in the active layer of Svalbard permafrost revealed by DNA- and RNA-based analyses

    Energy Technology Data Exchange (ETDEWEB)

    Schostag, Morten; Stibal, Marek; Jacobsen, Carsten S.; Baelum, Jacob; Tas, Neslihan; Elberling, Bo; Jansson, Janet K.; Semenchuk, Phillip; Prieme, Anders

    2015-04-30

    The active layer of soil overlaying permafrost in the Arctic is subjected to dramatic annual changes in temperature and soil chemistry, which likely affect bacterial activity and community structure. We studied seasonal variations in the bacterial community of active layer soil from Svalbard (78°N) by co-extracting DNA and RNA from 12 soil cores collected monthly over a year. PCR amplicons of 16S rRNA genes (DNA) and reverse transcribed transcripts (cDNA) were quantified and sequenced to test for the effect of low winter temperature and seasonal variation in concentration of easily degradable organic matter on the bacterial communities. The copy number of 16S rRNA genes and transcripts revealed no distinct seasonal changes indicating potential bacterial activity during winter despite soil temperatures well below -10°C. Multivariate statistical analysis of the bacterial diversity data (DNA and cDNA libraries) revealed a season-based clustering of the samples, and, e.g., the relative abundance of potentially active Cyanobacteria peaked in June and Alphaproteobacteria increased over the summer and then declined from October to November. The structure of the bulk (DNA-based) community was significantly correlated with pH and dissolved organic carbon, while the potentially active (RNA-based) community structure was not significantly correlated with any of the measured soil parameters. A large fraction of the 16S rRNA transcripts was assigned to nitrogen-fixing bacteria (up to 24% in June) and phototrophic organisms (up to 48% in June) illustrating the potential importance of nitrogen fixation in otherwise nitrogen poor Arctic ecosystems and of phototrophic bacterial activity on the soil surface.

  18. Ten-year trends of atmospheric mercury in the high Arctic compared to Canadian sub-Arctic and mid-latitude sites

    Directory of Open Access Journals (Sweden)

    A. S. Cole

    2013-02-01

    Full Text Available Global emissions of mercury continue to change at the same time as the Arctic is experiencing ongoing climatic changes. Continuous monitoring of atmospheric mercury provides important information about long-term trends in the balance between transport, chemistry, and deposition of this pollutant in the Arctic atmosphere. Ten-year records of total gaseous mercury (TGM from 2000 to 2009 were analyzed from two high Arctic sites at Alert (Nunavut, Canada and Zeppelin Station (Svalbard, Norway; one sub-Arctic site at Kuujjuarapik (Nunavik, Québec, Canada; and three temperate Canadian sites at St. Anicet (Québec, Kejimkujik (Nova Scotia and Egbert (Ontario. Five of the six sites examined showed a decreasing trend over this time period. Overall trend estimates at high latitude sites were: −0.9% yr−1 (95% confidence limits: −1.4, 0 at Alert and no trend (−0.5, +0.7 at Zeppelin Station. Faster decreases were observed at the remainder of the sites: −2.1% yr−1 (−3.1, −1.1 at Kuujjuarapik, −1.9% yr−1 (−2.1, −1.8 at St. Anicet, −1.6% yr−1 (−2.4, −1.0 at Kejimkujik and −2.2% yr−1 (−2.8, −1.7 at Egbert. Trends at the sub-Arctic and mid-latitude sites agree with reported decreases in background TGM concentration since 1996 at Mace Head, Ireland, and Cape Point, South Africa, but conflict with estimates showing an increase in global anthropogenic emissions over a similar period. Trends in TGM at the two high Arctic sites were not only less negative (or neutral overall but much more variable by season. Possible reasons for differences in seasonal and overall trends at the Arctic sites compared to those at lower latitudes are discussed, as well as implications for the Arctic mercury cycle. The first calculations of multi-year trends in reactive gaseous mercury (RGM and total particulate mercury (TPM at Alert were also performed, indicating increases from 2002 to 2009

  19. Accumulation, metabolism, and food-chain transfer of chlorinated and brominated contaminants in subadult white whales (Delphinapterus leucas) and narwhals (Monodon monoceros) from Svalbard, Norway.

    Science.gov (United States)

    Wolkers, H; Lydersen, C; Kovacs, K M; Burkow, I; van Bavel, B

    2006-01-01

    The concentrations and patterns of polychlorinated biphenyls (PCBs), chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs) were studied in white whales (Delphinapterus leucas) and narwhals (Monodon monoceros) from Svalbard, Norway. In addition, their main food items were included in the study. In the whales, a broad range of pollutants was found in relatively high concentrations. PCBs and pesticides were approximately 3000 and 8000 ng/g lipid, respectively, for white whales and three times higher for narwhals. PBDEs 47 were approximately 70 ng/g lipid for white whales and 170 ng/g lipid for narwhals. Compared with other marine mammals from the same area, contaminant levels are among the highest levels ever measured. These high levels are likely in part because of a decreased capacity to metabolize contaminants. Metabolic indices indicated that most compounds accumulate to the same degree in white whales and narwhals, but for some toxaphenes and chlordanes, narwhals might have a decreased metabolism and consequently a higher accumulation. The three-times-higher contaminant levels in blubber of narwhals was further explained by substantially higher contaminant levels in their more benthic diet. The high levels and broad pattern of accumulating pollutants make white whales and narwhals excellent indicators for a wide range of contaminants in the Arctic. PMID:16237494

  20. 白令海与西北冰洋表层沉积物中四醚膜类脂物研究及其生态和环境指示意义%Spatial Distribution Patterns of GDGTs in the Surface Sediments from the Bering Sea and Arctic Ocean and Their Environmental Significances

    Institute of Scientific and Technical Information of China (English)

    王寿刚; 王汝建; 陈建芳; 陈志华; 程振波; 汪卫国; 黄元辉

    2013-01-01

    Biomarker Glycerol Dialkyl Glycerol Tetraethers (GDGTs) was analyzed in 65 surface sediments from the Bering Sea and western Arctic Ocean recovered during the 3rd and 4rd Chinese National Arctic Expeditions. The distribution patterns of isoprenoid and branched GDGTs concentration are divided by the Chukchi and Beaufort Sea Slope. GDGTs concentration is higher in the south of the slope than that in the north, which is controlled by water column productivity and terrestrial organic matter input. GDGTs based BIT suggests that terrestrial organic matter input increases from the north Chukchi Sea to Alpha Ridge, compared with marine organic matter, which is consistent with the results retrieved from organic carbon isotope ratios, suggesting that BIT is a reliable proxy in the Arctic Ocean. Sea Surface Temperatures ( SST) derived by TEXL86 are not related to modern annual or summer mean SST, probably because of the mixed signal from terrestrial isprenoid GDGTs and low archaeal productivity in high Arctic region. Cyclisation ratio of Branched Tetraethers (CBT) show strong increase from seasonal sea ice area to permanent sea ice area, which may prove that CBT is sensitive to sea ice coverage. However, its mechanism remained unclear. Reconstructed terrestrial annual mean atmospheric temperature (MAT) and soil pH from branched GDGTs based CBT and Methylation index of Branched Tetraether ( MBT) show extremely variability, which is probably affected by complicated sediment sources and soil mixing in transportation process.%通过对中国第3次和第4次北极考察在白令海和西北冰洋采集的65个表层样沉积物中生物标记物四醚膜类脂物(GDGTs)的研究,发现西北冰洋表层沉积物中类异戊二烯和支链GDGTs的浓度分布大致以楚科奇海和波弗特海的陆坡为界线,呈现南高北低的特征,这一特征主要与水体生产力和陆源有机质的输入量有关.基于GDGTs的陆源输入指数BIT显示,从楚科奇海北部到

  1. Arctic Rabies – A Review

    Directory of Open Access Journals (Sweden)

    Prestrud Pål

    2004-03-01

    Full Text Available Rabies seems to persist throughout most arctic regions, and the northern parts of Norway, Sweden and Finland, is the only part of the Arctic where rabies has not been diagnosed in recent time. The arctic fox is the main host, and the same arctic virus variant seems to infect the arctic fox throughout the range of this species. The epidemiology of rabies seems to have certain common characteristics in arctic regions, but main questions such as the maintenance and spread of the disease remains largely unknown. The virus has spread and initiated new epidemics also in other species such as the red fox and the racoon dog. Large land areas and cold climate complicate the control of the disease, but experimental oral vaccination of arctic foxes has been successful. This article summarises the current knowledge and the typical characteristics of arctic rabies including its distribution and epidemiology.

  2. Measuring ignitability for in situ burning of oil spills weathered under Arctic conditions: From laboratory studies to large-scale field experiments

    DEFF Research Database (Denmark)

    Fritt-Rasmussen, Janne; Brandvik, Per Johan

    2011-01-01

    This paper compares the ignitability of Troll B crude oil weathered under simulated Arctic conditions (0%, 50% and 90% ice cover). The experiments were performed in different scales at SINTEF’s laboratories in Trondheim, field research station on Svalbard and in broken ice (70–90% ice cover...... process, and 70% ice or more reduces the weathering and allows a longer time window for in situ burning. The results from the Barents Sea revealed that weathering and ignitability can vary within an oil slick. This field use of the burning cell demonstrated that it can be used as an operational tool...... to monitor the ignitability of oil spills....

  3. Response of bacterioplankton activity in an Arctic fjord system to elevated pCO2: results from a mesocosm perturbation study

    OpenAIRE

    Riebesell, U.; Engel, A.; K. G. Schulz; Sperling, M.; C. Borchard; J. Piontek

    2013-01-01

    The effect of elevated seawater carbon dioxide (CO2) on the activity of a natural bacterioplankton community in an Arctic fjord system was investigated by a mesocosm perturbation study in the frame of the European Project on Ocean Acidification (EPOCA). A pCO2 range of 175–1085 μatm was set up in nine mesocosms deployed in the Kongsfjorden (Svalbard). The activity of natural extracellular enzyme assemblages increased in response to acidification. Rates of β-glucosidase and leucine-aminop...

  4. Response of bacterioplankton activity in an Arctic fjord system to elevated pCO2: results from a mesocosm perturbation study

    OpenAIRE

    Riebesell, U.; Engel, A.; K. G. Schulz; Sperling, M.; C. Borchard; J. Piontek

    2012-01-01

    The effect of elevated seawater carbon dioxide (CO2) on the activity of a natural bacterioplankton community in an Arctic fjord system was investigated by a mesocosm perturbation study in the frame of the European Project on Ocean Acidification (EPOCA). A pCO2 range of 175–1085 μatm was set up in nine mesocosms deployed in the Kongsfjorden (Svalbard). The bacterioplankton communities responded to rising chlorophyll a concentrations after a lag phase of only a few days with increasing ...

  5. Arctic satellite thermal infrared CH4 data compared to surface in-situ and total column measurements

    Science.gov (United States)

    Yurganov, L.; Leifer, I.; Xiong, X.

    2013-12-01

    The trace gas sensitivity of Thermal InfraRed (TIR) sounders (AIRS, IASI, TANSO) is greatest in the middle and upper troposphere; though, lower troposphere (1-2 km of altitude) sensitivity is less but not negligible. As a result, where methane largely is constrained to the lower troposphere, as is common in the Arctic particularly the marine Arctic, retrievals from these instruments provides important synoptic data on high latitude methane sources. Low Arctic water vapor content favors a better sensitivity to methane as well: H2O is the main absorber in the 7.8 micrometers spectral region. Both AIRS/Aqua v6 (NASA) and IASI/Metop-A (NOAA/NESDIS/CLASS retrievals) methane data averaged over 0-4 km altitude clearly demonstrate increased methane concentrations over the Barents and Norwegian Seas (BNS) with seasonal maximum in December - March. Similar increases are observed over the Kara, Laptev, and Chukchi Seas for September-November, i.e. during the period of minimum ice cover over the Arctic (Figures 1 and 2). Comparison of a long series of AIRS data with in situ methane concentrations at the Zeppelin NILU observatory (Svalbard) show good agreement both in amplitude and phase of seasonal variations. Agreement with Barrow NOAA continuous methane in situ data is much worse, which likely results from lower thermal contrast in winter over the cold and icy surfaces of the Eastern Arctic. Further surface validation is by a comparison of total methane columns with the Sun-Tracking FTIR at Ny-Alesund, Svalbard (TCCON network). These analyses demonstrate that TIR satellites are capable of detecting Arctic methane enhancements from space, particularly over relatively warm year-round water surfaces such as the BNS. Ongoing research is addressing further verification of retrieved methane columns by collecting data with a cavity ring-down spectroscopy analyzer for methane and carbon dioxide on board of the Russian Research Vessel Akademik Fedorov during the expedition NABOS-2013

  6. Alteration of glacigenic landforms by gravitational mass movements, Ragnarbreen and Ebbabreen, Svalbard

    Science.gov (United States)

    Ewertowski, Marek; Pleskot, Krzysztof; Tomczyk, Aleksandra

    2015-04-01

    The extensive recession of Svalbard's glaciers exposed areas containing large amount of dead-ice covered by relatively thin - usually less than a couple of meters - veneer of debris. This landscape can be very dynamic, mainly due to the mass movement processes and dead-ice melting. Continuous redistribution of sediments causes several phases of debris transfer and relief inversion. Hence, the primary glacial deposits released from ice are subsequently transferred by mass movement processes, until they finally reach more stable position. Investigations of dynamics of the mass movement and the way in which they alter the property of glacigenic sediments are therefore cruicial for proper understanding of sedimentary records of previous glaciations. The main objectives of this study were to: (1) quantify short-term dynamic of mass wasting processes; (2) investigate the transformation of the sediment's characteristic by mass wasting processes; (3) asses the contribution of different process to the overall dynamic of proglacial landscape. We focused on the mass-wasting processes in the forelands of two glaciers, Ebbabreen and Ragnarbreen, located near the Petuniabukta at the northern end of the Billefjorden, Spitsbergen. Repetitive topographic scanning was combined with sedimentological analysis of: grain size, clast shape in macro and micro scale and thin sections. Debris falls, slides, rolls and flows were the most important processes leading to reworking of glacigenic sediments and altering their properties. Contribution of different processes to the overall dynamic of the landforms was related mainly to the local conditions. Four different morphological types of sites were identified: (1) near vertical ice-cliffs covered with debris, transformed mainly due to dead-ice backwasting and debris falls and slides, (2) steep debris slopes with exposed ice-cores dominated by debris slides, (3) gentle sediment-mantled slopes transformed due to debris flows, and (4) non

  7. Global Ex-Situ Crop Diversity Conservation and the Svalbard Global Seed Vault: Assessing the Current Status

    OpenAIRE

    Westengen, Ola T; Jeppson, Simon; Guarino, Luigi

    2013-01-01

    Ex-situ conservation of crop diversity is a global concern, and the development of an efficient and sustainable conservation system is a historic priority recognized in international law and policy. We assess the completeness of the safety duplication collection in the Svalbard Global Seed Vault with respect to data on the world's ex-situ collections as reported by the Food and Agriculture Organization of the United Nations. Currently, 774,601 samples are deposited at Svalbard by 53 genebanks...

  8. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale. PMID:27149113

  9. Origin of a 'Southern Hemisphere' geochemical signature in the Arctic upper mantle.

    Science.gov (United States)

    Goldstein, Steven L; Soffer, Gad; Langmuir, Charles H; Lehnert, Kerstin A; Graham, David W; Michael, Peter J

    2008-05-01

    The Gakkel ridge, which extends under the Arctic ice cap for approximately 1,800 km, is the slowest spreading ocean ridge on Earth. Its spreading created the Eurasian basin, which is isolated from the rest of the oceanic mantle by North America, Eurasia and the Lomonosov ridge. The Gakkel ridge thus provides unique opportunities to investigate the composition of the sub-Arctic mantle and mantle heterogeneity and melting at the lower limits of seafloor spreading. The first results of the 2001 Arctic Mid-Ocean Ridge Expedition (ref. 1) divided the Gakkel ridge into three tectonic segments, composed of robust western and eastern volcanic zones separated by a 'sparsely magmatic zone'. On the basis of Sr-Nd-Pb isotope ratios and trace elements in basalts from the spreading axis, we show that the sparsely magmatic zone contains an abrupt mantle compositional boundary. Basalts to the west of the boundary display affinities to the Southern Hemisphere 'Dupal' isotopic province, whereas those to the east-closest to the Eurasian continent and where the spreading rate is slowest-display affinities to 'Northern Hemisphere' ridges. The western zone is the only known spreading ridge outside the Southern Hemisphere that samples a significant upper-mantle region with Dupal-like characteristics. Although the cause of Dupal mantle has been long debated, we show that the source of this signature beneath the western Gakkel ridge was subcontinental lithospheric mantle that delaminated and became integrated into the convecting Arctic asthenosphere. This occurred as North Atlantic mantle propagated north into the Arctic during the separation of Svalbard and Greenland. PMID:18451860

  10. On the Flow of Atlantic Water Towards the Arctic Ocean; a Synergy Between Altimetry and Hydrography.

    Science.gov (United States)

    Chafik, L.; Nilsson, J.; Skagseth, O.; Lundberg, P.

    2015-12-01

    The Arctic climate is strongly influenced by the inflow of warm Atlantic water conveyed by the Norwegian Atlantic Slope Current (NwASC); the main heat conveyor into the Arctic Ocean. Based on sea surface height (SSH) data from altimetry, we develop a dynamical measure of the NwASC transport to diagnose its spatio-temporal variability. This supports a dynamical division of the NwASC into two flow regimes; the Svinøy Branch (SvB) in the Norwegian Sea, and the Fram Strait Branch (FSB) west of Spitsbergen. The SvB transport is well correlated with the SSH and atmospheric variability within the Nordic Seas, factors that also affect the inflow to the Barents Sea. In contrast, the FSB is regulated by regional atmospheric patterns around Svalbard and northern Barents Sea. We further relate anomalous flow events to temperature fluctuations of Atlantic water. A warm anomaly is found to propagate northwards, with a tendency to amplify enroute, after events of strong flow in the Norwegian Sea. A roughly 12-months delayed temperature signal is identified in the FSB. This suggests that hydrographic anomalies both upstream from the North Atlantic, and locally generated in the Norwegian Sea, are important for the oceanic heat and salt transport that eventually enters into the Arctic. We believe that the combination of the flow from altimetry and temperature fluctuations in the Nordic Seas can be used to qualitatively predict warm anomalies towards the Arctic Ocean, which could be a valuable addition to the forecast skill of the statistical Arctic sea-ice models.

  11. A Holocene cryptotephra record from the Chukchi margin: the first tephrostratigraphic study in the Arctic Ocean

    OpenAIRE

    Ponomareva, Vera; Polyak, Leonid; Portnyagin, Maxim; Abbott, Peter; Davies, Siwan

    2014-01-01

    Developing geochronology for sediments in the Arctic Ocean and its continental margins is an important but challenging task complicated by multiple problems. In particular, the Chukchi/Beaufort margin, a critical area for reconstructing paleoceanographic conditions in the Pacific sector of the Arctic, features widespread dissolution of calcareous material, which limits posibilities for radiocarbon chronology. In order to evaluate the untapped potential of tephrochronology for constraining the...

  12. Modelling temperature-dependent heat production over decades in High Arctic coal waste rock piles

    DEFF Research Database (Denmark)

    Hollesen, Jørgen; Elberling, Bo; Jansson, P.E.

    2011-01-01

    Subsurface heat production from oxidation of pyrite is an important process that may increase subsurface temperatures within coal waste rock piles and increase the release of acid mine drainage, AMD. Waste rock piles in the Arctic are especially vulnerable to changes in subsurface temperatures...... as the release of AMD normally is limited by permafrost. Here we show that temperatures within a 20 year old heat-producing waste rock pile in Svalbard (78°N) can be modelled by the one-dimensional heat and water flow model (CoupModel) with a new temperature-dependent heat-production module that includes both...... biological and chemical oxidation processes and heat source depletion over time. Inputs to the model are meteorological measurements, physical properties of the waste rock material and measured subsurface heat-production rates. Measured mean annual subsurface temperatures within the waste rock pile are up...

  13. Comparison of Magnetic and Moessbauer Results Obtained for Palaeozoic Rocks of Hornsund, Southern Spitsbergen, Arctic

    International Nuclear Information System (INIS)

    This analysis was performed as a part of the palaeomagnetic project focused on the reconstruction of the palaeogeographic position of the Svalbard Archipelago and adjacent crustal units (European Arctic) in the Palaeozoic and Mesozoic. Three rock formations | Cambrian, Devonian and Carboniferous were sampled in the area of Hornsund, southern Spitsbergen. The main aim of the presented study is to identify ferromagnetic minerals (sensu lato) - the carriers of the natural remanent magnetisation in the investigated rocks. A wide range of magnetic methods were used: the Lowrie tests, unblocking temperatures determinations and the measurement of coercivity spectra as well as the Moessbauer studies. In Devonian and Carboniferous samples all applied methods indicate the domination of the hematite natural remanent magnetisation carrier. In Cambrian rocks magnetic measurements reveal a mixture of ferromagnetic (sensu lato) minerals with varying coercivities and unblocking temperatures. The Moessbauer data improve the identification, suggesting that in Cambrian rocks the carrier of the dominating natural remanent magnetisation component is maghemite. (authors)

  14. Deeper snow alters soil nutrient availability and leaf nutrient status in high Arctic tundra

    DEFF Research Database (Denmark)

    Semenchuk, Philipp R.; Elberling, Bo; Amtorp, Cecilie;

    2015-01-01

    Svalbard in two vegetation types spanning three moisture regimes. We measured growing-season availability of ammonium (NH4 (+)), nitrate (NO3 (-)), total dissolved organic carbon (DOC) and nitrogen (TON) in soil; C, N, delta N-15 and chlorophyll content in Salix polaris leaves; and leaf sizes of Salix...... season. Changing nutrient availability may be reflected in plant N and chlorophyll content and lead to increased photosynthetic capacity, plant growth, and ultimately carbon (C) assimilation by plants. In this study, we increased snow depth and thereby cold-season soil temperatures in high Arctic...... some species. Responses to cold-season soil warming are vegetation type- and species-specific, with potentially stronger responses in moister vegetation types. This study therefore highlights the contrasting effect of snow in a tundra landscape and has important implications for projections of whole...

  15. Mass changes in Arctic ice caps and glaciers: implications of regionalizing elevation changes

    DEFF Research Database (Denmark)

    Nilsson, Johan; Sørensen, Louise Sandberg; Barletta, Valentina Roberta; Forsberg, René

    2015-01-01

    regional mass balance of Arctic ice caps and glaciers to different regionalization schemes. The sensitivity analysis is based on studying the spread of mass changes and their associated errors, and the suitability of the different regionalization techniques is assessed through cross validation.The cross-validation...... results shows comparable accuracies for all regionalization methods, but the inferred mass changein individual regions, such as Svalbard and Iceland, can vary up to 4 Gt a-1, which exceeds the estimated errors by roughly50 % for these regions. This study further finds that this spread in mass balance is......The mass balance of glaciers and ice caps is sensitive to changing climate conditions. The mass changes derived n this study are determined from elevation changes derived measured by the Ice, Cloud, and land Elevation Satellite (ICESat) for the time period 2003–2009. Four methods, based on...

  16. Aerosol absorption coefficient and Equivalent Black Carbon by parallel operation of AE31 and AE33 aethalometers at the Zeppelin station, Ny Ålesund, Svalbard

    Science.gov (United States)

    Eleftheriadis, Konstantinos; Kalogridis, Athina-Cerise; Vratolis, Sterios; Fiebig, Markus

    2016-04-01

    Light absorbing carbon in atmospheric aerosol plays a critical role in radiative forcing and climate change. Despite the long term measurements across the Arctic, comparing data obtained by a variety of methods across stations requires caution. A method for extracting the aerosol absorption coefficient from data obtained over the decades by filter based instrument is still under development. An IASOA Aerosol working group has been initiated to address this and other cross-site aerosol comparison opportunities. Continuous ambient measurements of EBC/light attenuation by means of a Magee Sci. AE-31 aethalometer operating at the Zeppelinfjellet station (474 m asl; 78°54'N, 11°53'E), Ny Ålesund, Svalbard, have been available since 2001 (Eleftheriadis et al, 2009), while a new aethalometer model (AE33, Drinovec et al, 2014) has been installed to operate in parallel from the same inlet since June 2015. Measurements are recorded by a Labview routine collecting all available parameters reported by the two instrument via RS232 protocol. Data are reported at 1 and 10 minute intervals as averages for EBC (μg m-3) and aerosol absorption coefficients (Mm-1) by means of routine designed to report Near Real Time NRT data at the EBAS WDCA database (ebas.nilu.no) Results for the first 6 month period are reported here in an attempt to evaluate comparative performance of the two instruments in terms of their response with respect to the variable aerosol load of light absorbing carbon during the warm and cold seasons found in the high arctic. The application of available conversion schemes for obtaining the absorption coefficient by the two instruments is found to demonstrate a marked difference in their output. During clean periods of low aerosol load (EBC instruments display a better agreement with regression slope for the 880 nm signal between the two at ~ 0.9 compared to a slope at ~ 0.6 during the period of higher absorbing carbon loads (400< EBC<30 ng m-3) A detailed

  17. Modelling the regional climate and isotopic composition of Svalbard precipitation using REMOiso

    DEFF Research Database (Denmark)

    Divine..[], D.V.; Sjolte, Jesper; Isaksson, E.;

    2011-01-01

    Simulations of a regional (approx. 50 km resolution) circulation model REMOiso with embedded stable water isotope module covering the period 1958-2001 are compared with the two instrumental climate and four isotope series (d18O) from western Svalbard. We examine the data from ice cores drilled on...... Svalbard ice caps in 1997 (Lomonosovfonna, 1250 m asl) and 2005 (Holtedahlfonna, 1150 m asl) and the GNIP series from Ny-angstrom lesund and Isfjord Radio. The surface air temperature (SAT) and precipitation data from Longyearbyen and Ny-angstrom lesund are used to assess the skill of the model in...... reproducing the local climate. The model successfully captures the climate variations on the daily to multidecadal times scales although it tends to systematically underestimate the winter SAT. Analysis suggests that REMOiso performs better at simulating isotope compositions of precipitation in the winter...

  18. Osmotic stress and recovery in field populations of Zygnema sp. (Zygnematophyceae, Streptophyta) on Svalbard (High Arctic) subjected to natural desiccation

    Czech Academy of Sciences Publication Activity Database

    Pichrtová, Martina; Hájek, Tomáš; Elster, Josef

    2014-01-01

    Roč. 89, č. 2 (2014), s. 270-280. ISSN 0168-6496 Institutional support: RVO:67985939 Keywords : ecophysiology * green algae * plasmolysis Subject RIV: EH - Ecology, Behaviour Impact factor: 3.568, year: 2014

  19. A comparison of annual and seasonal carbon dioxide effluxes between subarctic Sweden and high-arctic Svalbard

    DEFF Research Database (Denmark)

    Björkman, Mats P.; Morgner, Elke; Björk, Robert G.; Cooper, Elisabet J.; Elberling, Bo; Klemedtsson, Leif

    2010-01-01

    winter effluxes between snow regimes or vegetation types, indicating that spatial variability in winter soil CO2 effluxes are not directly linked to snow cover thickness or soil temperatures. Total winter emissions (0.004– 0.248 kg CO2 m–2) were found to be in the lower range of those previously...

  20. A taphonomic study of marine reptiles from the Upper Jurassic of Svalbard

    OpenAIRE

    2012-01-01

    In this study the taphonomy of a collection of 25 marine reptiles from the Slottsmøya member, (Agardhfjellet Formation) Svalbard was investigated. The marine reptiles which include ichthyosaurs, plesiosaurs and pliosaurs were excavated during seven field seasons (2004- 2011). The specimens are divided into three preservation categories: articulated specimens, partly articulated specimens and disarticulated specimens. The specimens are discussed in relation to possible causes of death, the pos...

  1. The capabilities of the EISCAT Svalbard Radar for inter-hemispheric coordinated studies

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this article we want to present the EISCAT Svalbard Radar (ESR) in some detail, as well as some of the instruments of interest for ionospheric and magnetospheric research that are located in the vicinity of it. We particularly describe how this instrument cluster, close to the geomagnetic conjugate point of the Chinese Antarctic Zhongshan Station, can contribute to inter-hemispheric coordinated studies of the polar ionosphere.

  2. Greenland sharks (Somniosus microcephalus) scavenge offal from minke (Balaenoptera acutorostrata) whaling operations in Svalbard (Norway)

    OpenAIRE

    Leclerc, Lisa-Marie; Lydersen, Christian; Haug, Tore; Kevin A Glover; Fisk, Aaron T.; Kovacs, Kit M.

    2011-01-01

    Minke whale (Balaenoptera acutorostrata) tissue (mainly blubber) was found in the gastrointestinal tracks of Greenland sharks (Somniosus microcephalus) collected in Kongsfjorden, Svalbard, Norway. In order to determine whether the sharks were actively hunting the whales, finding naturally dead whales or consuming offal from whaling, we checked the genetic identity of the whale tissue found in the sharks against the DNA register for minke whales taken in Norwegian whaling operations. All of th...

  3. Ka-Band Site Characterization of the NASA Near Earth Network in Svalbard, Norway

    Science.gov (United States)

    Acosta, R.; Morse, J.; Nessel, J.; Zemba, M.; Tuttle, K.; Caroglanian, A.; Younes, B.; Pedersen, Sten-Chirstian

    2011-01-01

    Critical to NASA s rapid migration toward Ka-Band is the comprehensive characterization of the communication channels at NASA's ground sites to determine the effects of the atmosphere on signal propagation and the network's ability to support various classes of users in different orbits. Accordingly, NASA has initiated a number of studies involving the ground sites of its Near Earth and Deep Space Networks. Recently, NASA concluded a memorandum of agreement (MOA) with the Norwegian Space Centre of the Kingdom of Norway and began a joint site characterization study to determine the atmospheric effects on Ka-Band links at the Svalbard Satellite Station in Norway, which remains a critical component of NASA s Near Earth Communication Network (NEN). System planning and design for Ka-band links at the Svalbard site cannot be optimally achieved unless measured attenuation statistics (e.g. cumulative distribution functions (CDF)) are obtained. In general, the CDF will determine the necessary system margin and overall system availability due to the atmospheric effects. To statistically characterize the attenuation statistics at the Svalbard site, NASA has constructed a ground-based monitoring station consisting of a multi-channel total power radiometer (25.5 - 26.5 GHz) and a weather monitoring station to continuously measure (at 1 second intervals) attenuation and excess noise (brightness temperature). These instruments have been tested in a laboratory environment as well as in an analogous outdoor climate (i.e. winter in Northeast Ohio), and the station was deployed in Svalbard, Norway in May 2011. The measurement campaign is planned to last a minimum of 3 years but not exceeding a maximum of 5 years.

  4. The Nippon/Norway Svalbard Meteor Radar: First results of small-scale structure observations

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Nippon/Norway Svalbard Meteor Radar(NSMR), has been in operation since March 2001. While primarily thought of as an instrument for examining mean wind, tidal and gravity wave neutral atmosphere dynamics in the upper mesosphere region, it is also possible to investigate spatial and temporal structure of temperature and windshear. Here, the radar itself is described followed by a presentation of these derived parameters.

  5. Geology, mineralogy and geochemistry of the Holmsletfjella Au-As occurrence, West Spitsbergen Fold Belt, Svalbard

    OpenAIRE

    Simonsen, Håvard Kvåle

    2012-01-01

    Holmsletfjella is situated on the southern side of St. Jonsfjorden on the archipelago of Svalbard. The drill core herein studied is part of an exploration program by Store Norske. Chemical analysis of the drill cores in combination with the geological history have reviled the Holmsletfjella Formation and the Ultramafic Vestgötabreen Complex to have been altered by fluids migrating through the rocks during the formation of the Caledonian mountain chain. These fluids were sourced from VAMSNAZ (...

  6. Modeling the temperature evolution of Svalbard permafrost during the 20th and 21st century

    OpenAIRE

    B. Etzelmüller; T. V. Schuler; K. Isaksen; H. H. Christiansen; H. Farbrot; R. Benestad

    2011-01-01

    Variations in ground thermal conditions in Svalbard were studied based on measurements and modelling. Ground temperature data from boreholes were used to calibrate a transient heat flow model describing depth and time variations in temperatures. The model was subsequently forced with historical surface air temperature records and possible future temperatures downscaled from multiple global climate models. We discuss ground temperature development since the early 20th century, and the thermal ...

  7. Coordinated Eastern Arctic Experiment (CEAREX) Data

    Data.gov (United States)

    National Aeronautics and Space Administration — CEAREX was a multi-platform field program conducted in the Norwegian Seas and Greenland north to Svalbard from September 1988 through May 1989. Canada, Denmark,...

  8. Radiocaesium ({sup 137}Cs) in marine mammals from Svalbard, the Barents Sea and the North Greenland Sea

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Magnus; Kovacs, Kit M.; Lydersen, Christian [Norwegian Polar Institute, N-9296, Tromsoe (Norway); Gwynn, Justin P.; Dowdall, Mark [Norwegian Radiation Protection Authority, N-9296, Tromsoe (Norway)

    2006-06-15

    Specific activities of the anthropogenic radionuclide, {sup 137}Cs, were determined in marine mammals from Svalbard and the Barents and North Greenland Seas. Muscle samples were collected from 12 polar bears, 15 ringed seals, 10 hooded seals, 7 bearded seals, 14 harp seals, one walrus, one white whale and one blue whale in the period 2000-2003. The mean concentrations (+/-SD) of {sup 137}Cs were: 0.72+/-0.62 Bq/kg wet weight (w.w.) for polar bears; 0.49+/-0.07 Bq/kg w.w. for ringed seals; 0.25+/-0.10 Bq/kg w.w. for hooded seals; 0.22+/-0.11 Bq/kg w.w. for bearded seals; 0.36+/-0.13 Bq/kg w.w. for harp seals; 0.67 Bq/kg w.w. for the white whale sample; 0.24 Bq/kg w.w. for the blue whale; and below detection limit for the walrus. Significant differences in {sup 137}Cs specific activities between some of the species were found. Ringed seals had higher specific activities than the other seal species in the study. Bearded seals and hooded seals had similar values, which were both significantly lower than the harp seal values. The results in the present study are consistent with previous reported results, indicating low specific activities of {sup 137}Cs in Arctic marine mammals in the Barents Sea and Greenland Sea region during the last 20 years. The species specific differences found may be explained by varying diet or movement and distribution patterns between species. No age related patterns were found in specific activities for the two species (polar bears and hooded seals) for which sufficient data was available. Concentration factors (CF) of {sup 137}Cs from seawater were determined for polar bears, ringed, bearded, harp and hooded seals. Mean CF values ranged from 79+/-32 (SD) for bearded seals sampled in 2002 to 244+/-36 (SD) for ringed seals sampled in 2003 these CF values are higher than those reported for fish and benthic organisms in the literature, suggesting bioaccumulation of {sup 137}Cs in the marine ecosystem. (author)

  9. Using Paleomagnetic, Geochemical and Structural Data to Recognize Post-metamorphic Tectonic Events in the Caledonide Terranes of Western Svalbard.

    Science.gov (United States)

    Michalski, K.; Manby, G.; Nejbert, K.; Domańska Siuda, J.; Burzyński, M.

    2015-12-01

    A total of 170 oriented palaeomagnetic samples of Proterozoic-Lower Palaeozoic metacarbonates and metabasites from 28 sites in Hornsund and Oscar II Land, Western Spitsbergen (Fig. 1A) were investigated at the Polish Academy of Sciences Institute of Geophysics . Petrographic and rock-magnetic analyses revealed that the ferromagnetic carriers are dominated by metamorphic pyrrhotite and Low-Ti magnetite. Simultaneous in situ laser ablation 40Ar/39Ar age determination of the samples indicate that a 426-380 Ma Caledonian sensu lato thermal overprint was followed by younger events in the 377-326 Ma and ca. 300 Ma intervals (Fig. 1B). The latter two ages appear to coincide with recently published seismic data indicating that Late Devonian - Carboniferous rifting was followed by similar crustal extension in the SW Barents shelf area in Late Carboniferous time. Published in situ palaeomagnetic directions from Hornsund area in SW Svalbard fit the Silurian sector of the Baltica reference path suggesting that the geometry of the sampled Caledonian Sofekammen Syncline was not modified during following Svalbardian or Eurekan deformation events (Fig. 1C). In contrast, palaeomagnetic directions obtained from Oscar II Land are distant from Caledonian sector of Baltica reference path (Fig. 1C). It is suggested here, that the most significant mechanism responsible for the rotation of the palaeomagnetic directions and modification of geometry of Caledonian tectonic structures of Oscar II Land was listric normal faulting related to the opening of the North Atlantic -Arctic Ocean Basins. Late Cretaceous- Early Tertiary Eurekan folding and thrust faulting appear to have had minor influence on the palaeomagnetic directions obtained. This study is part of the Polish National Science Centre - DEC 2011/03/D/ST10/05193 PALMAG 2012-2016 funded project . Fig. 1. A. Geological sketch map of Western Spitsbergen. B. Probability diagrams derived from insitu 40Ar/39Ar laser ablation age

  10. Cecal bacterial communities in wild Japanese rock ptarmigans and captive Svalbard rock ptarmigans.

    Science.gov (United States)

    Ushida, Kazunari; Segawa, Takahiro; Tsuchida, Sayaka; Murata, Koichi

    2016-02-01

    Preservation of indigenous gastrointestinal microbiota is deemed to be critical for successful captive breeding of endangered wild animals, yet its biology is poorly understood. Here, we investigated cecal bacterial communities in wild Japanese rock ptarmigans (Lagopus muta japonica) and compared them with those in Svalbard rock ptarmigans (L. m. hyperborea) in captivity. Ultra-deep sequencing of 16S rRNA gene indicated that the community structure of cecal microbiota in wild rock ptarmigans was remarkably different from that in captive Svalbard rock ptarmigans. Fundamental differences between bacterial communities in the two groups of birds were detected at the phylum level. Firmicutes, Actinobacteria, Bacteroidetes and Synergistetes were the major phyla detected in wild Japanese rock ptarmigans, whereas Firmicutes alone occupied more than 80% of abundance in captive Svalbard rock ptarmigans. Furthermore, unclassified genera of Coriobacteriaceae, Synergistaceae, Bacteroidaceae, Actinomycetaceae, Veillonellaceae and Clostridiales were the major taxa detected in wild individuals, whereas in zoo-reared birds, major genera were Ruminococcus, Blautia, Faecalibacterium and Akkermansia. Zoo-reared birds seemed to lack almost all rock ptarmigan-specific bacteria in their intestine, which may explain the relatively high rate of pathogenic infections affecting them. We show evidence that preservation and reconstitution of indigenous cecal microflora are critical for successful ex situ conservation and future re-introduction plan for the Japanese rock ptarmigan. PMID:26468217

  11. Brucella sp. antibodies in polar bears from Svalbard and the Barents Sea.

    Science.gov (United States)

    Tryland, M; Derocher, A E; Wiig, Y; Godfroid, J

    2001-07-01

    A prevalence of 5.4% of anti-Brucella sp. antibodies was found in plasma samples from 297 polar bears (Ursus maritimus) from Svalbard and the Barents Sea. Plasma was tested by the classical brucellosis tests Slow Agglutination of Wright (SAW), EDTA modified SAW and Rose Bengal test, as well as by an indirect Protein A ELISA. Only samples classified as positive in all tests were regarded as containing anti-Brucella sp. antibodies. A significant west to east increase in the proportion of bears with anti-Brucella sp. antibodies was found, with 3.6% (n = 253) at Svalbard (Spitsbergen, Nordaustlandet, Edgeøya, Barentsøya and Hopen), and 15.9% (n = 44) in the central Barents Sea. Anti-Brucella sp. antibodies were previously found in ringed seals (Phoca hispida) and harp seals (Phoca groenlandica) from the same geographical areas. The ringed seal is an important prey species for the Svalbard polar bear population, and may thus be a source of brucellosis for the bears. There are no indications of reproductive disorders caused by Brucella sp. or other infectious agents in our study polar bear population. Potential impacts of Brucella sp. exposure on individuals or the population are unknown. PMID:11504225

  12. Geographical Area and Life History Traits Influence Diet in an Arctic Marine Predator.

    Science.gov (United States)

    Tartu, Sabrina; Bourgeon, Sophie; Aars, Jon; Andersen, Magnus; Ehrich, Dorothee; Thiemann, Gregory W; Welker, Jeffrey M; Routti, Heli

    2016-01-01

    Global changes are thought to affect most Arctic species, yet some populations are more at risk. Today, the Barents Sea ecoregion is suffering the strongest sea ice retreat ever measured; and these changes are suspected to modify food access and thus diet of several species. Biochemical diet tracers enable investigation of diet in species such as polar bears (Ursus maritimus). We examined individual diet variation of female polar bears in Svalbard, Norway, and related it to year, season (spring and autumn), sampling area and breeding status (solitary, with cubs of the year or yearlings). Sampling areas were split according to their ice cover: North-West (less sea ice cover), South-East (larger amplitude in sea ice extent) and North-East/South-West (NESW) as bears from that zone are more mobile among all regions of Svalbard. We measured fatty acid (FA) composition in adipose tissue and carbon (δ13C) and nitrogen (δ15N) stable isotopes in plasma and red blood cells. Females feeding in the North-West area had lower δ15N values than those from the NESW. In South-East females, δ13C values were lower in autumn compared to spring and females seemed less selective in their diet as depicted by large variances in stable isotope values. Considering the differences in FA composition and stable isotope values, we suggest that females from the North-West and South-East could ingest a higher proportion of avian prey. With regard to breeding status, solitary females had higher δ15N values and smaller variance in their stable isotopic values than females with cubs, suggesting that solitary females were more selective and prey on higher trophic level species (i.e. seals). Overall, our results indicate that prey availability for Svalbard polar bears varies according to geographical area and prey selectivity differs according to breeding status. Our findings suggest that complex changes in sea ice and prey availability will interact to affect Svalbard polar bear feeding patterns

  13. Geographical Area and Life History Traits Influence Diet in an Arctic Marine Predator.

    Directory of Open Access Journals (Sweden)

    Sabrina Tartu

    Full Text Available Global changes are thought to affect most Arctic species, yet some populations are more at risk. Today, the Barents Sea ecoregion is suffering the strongest sea ice retreat ever measured; and these changes are suspected to modify food access and thus diet of several species. Biochemical diet tracers enable investigation of diet in species such as polar bears (Ursus maritimus. We examined individual diet variation of female polar bears in Svalbard, Norway, and related it to year, season (spring and autumn, sampling area and breeding status (solitary, with cubs of the year or yearlings. Sampling areas were split according to their ice cover: North-West (less sea ice cover, South-East (larger amplitude in sea ice extent and North-East/South-West (NESW as bears from that zone are more mobile among all regions of Svalbard. We measured fatty acid (FA composition in adipose tissue and carbon (δ13C and nitrogen (δ15N stable isotopes in plasma and red blood cells. Females feeding in the North-West area had lower δ15N values than those from the NESW. In South-East females, δ13C values were lower in autumn compared to spring and females seemed less selective in their diet as depicted by large variances in stable isotope values. Considering the differences in FA composition and stable isotope values, we suggest that females from the North-West and South-East could ingest a higher proportion of avian prey. With regard to breeding status, solitary females had higher δ15N values and smaller variance in their stable isotopic values than females with cubs, suggesting that solitary females were more selective and prey on higher trophic level species (i.e. seals. Overall, our results indicate that prey availability for Svalbard polar bears varies according to geographical area and prey selectivity differs according to breeding status. Our findings suggest that complex changes in sea ice and prey availability will interact to affect Svalbard polar bear feeding

  14. Communicating Arctic Change (Invited)

    Science.gov (United States)

    Serreze, M.

    2009-12-01

    Nowhere on the planet are emerging signals of climate change more visible than in the Arctic. Rapid warming, a quickly shrinking summer sea ice cover, and thawing permafrost, will have impacts that extend beyond the Arctic and may reverberate around the globe. The National Snow and Ice Data Center (NSIDC) of the University of Colorado has taken a leading role in trying to effectively communicate the science and importance of Arctic change. Our popular “Sea Ice News and Analysis” web site tracks the Arctic’s shrinking ice cover and provides scientific analysis with language that is accurate yet accessible to a wide audience. Our Education Center provides accessible information on all components of the Earth’s cryosphere, the changes being seen, and how scientists conduct research. A challenge faced by NSIDC is countering the increasing level of confusion and misinformation regarding Arctic and global change, a complex problem that reflects the low level of scientific literacy by much of the public, the difficulties many scientists face in communicating their findings in accurate but understandable terms, and efforts by some groups to deliberately misrepresent and distort climate change science. This talk will outline through examples ways in which NSIDC has been successful in science communication and education, as well as lessons learned from failures.

  15. Contest for Arctic

    International Nuclear Information System (INIS)

    Warming of Earth surface access the defrosting north extensiveness of economic activities. The Russian Federation (RF) has delegated two bathyscaphs in order to put capsule with Russian flag on the bottom under North Pole. In this paper the territorial pretensions of the RF on the Arctic region are discussed

  16. The Arctic Circle

    Science.gov (United States)

    McDonald, Siobhan

    2016-04-01

    My name is Siobhan McDonald. I am a visual artist living and working in Dublin. My studio is based in The School of Science at University College Dublin where I was Artist in Residence 2013-2015. A fascination with time and the changeable nature of landmass has led to ongoing conversations with scientists and research institutions across the interweaving disciplines of botany, biology and geology. I am developing a body of work following a recent research trip to the North Pole where I studied the disappearing landscape of the Arctic. Prompted by my experience of the Arctic shelf receding, this new work addresses issues of the instability of the earth's materiality. The work is grounded in an investigation of material processes, exploring the dynamic forces that transform matter and energy. This project combines art and science in a fascinating exploration of one of the Earth's last relatively untouched wilderness areas - the High Arctic to bring audiences on journeys to both real and artistically re-imagined Arctic spaces. CRYSTALLINE'S pivotal process is collaboration: with The European Space Agency; curator Helen Carey; palaeontologist Prof. Jenny McElwain, UCD; and with composer Irene Buckley. CRYSTALLINE explores our desire to make corporeal contact with geological phenomena in Polar Regions. From January 2016, in my collaboration with Jenny McElwain, I will focus on the study of plants and atmospheres from the Arctic regions as far back as 400 million years ago, to explore the essential 'nature' that, invisible to the eye, acts as imaginary portholes into other times. This work will be informed by my arctic tracings of sounds and images recorded in the glaciers of this disappearing frozen landscape. In doing so, the urgencies around the tipping of natural balances in this fragile region will be revealed. The final work will emerge from my forthcoming residency at the ESA in spring 2016. Here I will conduct a series of workshops in ESA Madrid to work with

  17. Intercontinental transport of black carbon to the Arctic free troposphere

    Science.gov (United States)

    Liu, Dantong; Quennehen, Boris; Allan, James; Darbyshire, Eoghan; Williams, Paul; Taylor, Jonathan; Flynn, Michael; Bower, Keith; Coe, Hugh

    2015-04-01

    Black carbon has a large radiative forcing potential in the Arctic, through altering the atmosphere's radiative balance and also initiating ice melt after deposition. Here we present an analysis of aerosol data collected aboard the UK Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft during five flights in the free troposphere in the region of Svalbard in March 2013 as part of the Natural Environment Research Council (NERC) Aerosol-Cloud Coupling and Climate Interaction in the Arctic (ACCACIA) project. A number of discrete layers of pollution typical of continental emissions were detected, evidenced by black carbon (measured using a single particle soot photometer), carbon monoxide, organic matter and sulphate (measured using an aerosol mass spectrometer). These were detected at all altitudes within the free troposphere (up to 8 km) and potential source regions were investigated on a plume-by-plume basis using FLEXPART and HYSPLIT. Continental areas were identified as separate potential sources for the different plumes, with transit times of up to 12 days. East Asia showed the strongest influence, being responsible for high concentration plumes at all layers and Europe was found to be responsible for plumes in the lower to mid troposphere. North America had a somewhat weaker influence and no significant influence from Northern Russia was found. Emissions inventory data was used in conjunction with the FLEXPART potential source footprints to try to estimate the relative significance of different sources and it was found that direct emissions from human activities (e.g. transport, industry) were more prevalent than open biomass burning. Significant loadings were detected (of the order of 100 ng sm-3 black carbon relative to CO concentrations of around 50 ppbv) even when instrumental data and model outputs suggest that significant precipitation occurred during uplift, indicating that inefficient scavenging is taking place.

  18. Microbial Mn(IV) and Fe(III) reduction in northern Barents Sea sediments under different conditions of ice cover and organic carbon deposition

    DEFF Research Database (Denmark)

    Nickel, Maren; Vandieken, Verona; Brüchert, Volker;

    2008-01-01

    Carbon oxidation rates and pathways were determined in two sediments at latitude 75° and 77°N southeast of Svalbard in the northern Barents Sea. Seasonal ice cover restricts primary production to few months a year, which determines the sedimentation rate of organic material to the seafloor. At one...... contrast, in a sediment that had not been ice covered for at least 12 months and with more organic carbon and a higher sedimentation rate, sulfate reduction was the most important anaerobic electron-accepting process (>80% of anaerobic carbon oxidation). In the upper 3 cm, microbial Fe and sulfate...

  19. Long-term experimentally deepened snow decreases growing-season respiration in a low- and high-arctic tundra ecosystem

    Science.gov (United States)

    Semenchuk, Philipp R.; Christiansen, Casper T.; Grogan, Paul; Elberling, Bo; Cooper, Elisabeth J.

    2016-05-01

    Tundra soils store large amounts of carbon (C) that could be released through enhanced ecosystem respiration (ER) as the arctic warms. Over time, this may change the quantity and quality of available soil C pools, which in-turn may feedback and regulate ER responses to climate warming. Therefore, short-term increases in ER rates due to experimental warming may not be sustained over longer periods, as observed in other studies. One important aspect, which is often overlooked, is how climatic changes affecting ER in one season may carry-over and determine ER in following seasons. Using snow fences, we increased snow depth and thereby winter soil temperatures in a high-arctic site in Svalbard (78°N) and a low-arctic site in the Northwest Territories, Canada (64°N), for 5 and 9 years, respectively. Deepened snow enhanced winter ER while having negligible effect on growing-season soil temperatures and soil moisture. Growing-season ER at the high-arctic site was not affected by the snow treatment after 2 years. However, surprisingly, the deepened snow treatments significantly reduced growing-season ER rates after 5 years at the high-arctic site and after 8-9 years at the low-arctic site. We speculate that the reduction in ER rates, that became apparent only after several years of experimental manipulation, may, at least in part, be due to prolonged depletion of labile C substrate as a result of warmer soils over multiple cold seasons. Long-term changes in winter climate may therefore significantly influence annual net C balance not just because of increased wintertime C loss but also because of "legacy" effects on ER rates during the following growing seasons.

  20. The Eocene Eurekan deformation in the Arctic - architecture and kinematics of a strange foldbelt

    Science.gov (United States)

    Piepjohn, Karsten; von Gosen, Werner; Tessensohn, Franz; Reinhardt, Lutz

    2016-04-01

    The polyphase Paleogene Eurekan deformational history in the Arctic represents a complex sequence of successive tectonic stages, which produced a number of intra-continental deformation zones with changing, sometimes opposing, lateral, oblique, and convergent kinematics along the involved plate boundaries in the Canadian Arctic Archipelago, North Greenland, and Svalbard. The Eurekan deformation is characterized by different structural styles with the development of fold-and-thrust belts in Spitsbergen and in the Canadian Arctic, distinct compressional thrust zones in North Greenland and Ellesmere Island, large systems of strike-slip fault zones in Spitsbergen, Northeast Greenland and Ellesmere Island, and the combination of both compressional and lateral fault zones in northern Ellesmere Island. Eurekan tectonism was caused by the opening and continuous evolution of the Eurasian Basin in connection with the development of the Labrador Sea/Baffin Bay and the North Atlantic Ocean spreading ridges. The following tectonic stages can be distinguished which are responsible for the Eurekan deformation: - Pre-Eurekan Stage: sea-floor spreading in Labrador Sea and rifting in Baffin Bay, Norwegian/Greenland seas and the Eurasian Basin (100-53 Ma). - Eurekan Stage 1: sea-floor spreading and transform faults around Greenland resulted in a NE-directed movement with (a) sinistral transpression along Nares Strait and probably sinistral motion along the fault zones parallel to the north margin of Ellesmere Island, and (b) compression at the West Spitsbergen Fold-and-Thrust Belt (53-47 Ma). - Eurekan Stage 2: NW-wards directed movement of Greenland with (a) compression along Nares Strait and parts of Ellesmere Island combined with dextral motions parallel to the continental margin of the Canadian Arctic Archipelago (b) and dextral strike-slip tectonics along Fram Strait (47-34 Ma). - Post-Eurekan Stage: termination of sea-floor spreading in Labrador Sea/Baffin Bay and separation of

  1. Invertebrate communities of the High Arctic ponds in Hornsund

    Directory of Open Access Journals (Sweden)

    Luoto Tomi P.

    2016-03-01

    Full Text Available How environmental conditions influence current distributions of organisms at the local scale in sensitive High Arctic freshwaters is essential to understand in order to better comprehend the cascading consequences of the ongoing climate change. This knowledge is also important background data for paleolimnological assessments of long-term limnoecological changes and in describing the range of environmental variability. We sampled five limnologically different freshwater sites from the Fuglebergsletta marine terrace in Hornsund, southern Svalbard, for aquatic invertebrates. Invertebrate communities were tested against non-climatic environmental drivers as limnological and catchment variables. A clear separation in the communities between the sites was observed. The largest and deepest lake was characterized by a diverse Chironomidae community but Cladocera were absent. In a pond with marine influence, crustaceans, such as Ostracoda, Amphipoda, and calanoid Copepoda were the most abundant invertebrates. Two nutrient-rich ponds were dominated by a chironomid, Orthocladius consobrinus, whereas themost eutrophic pond was dominated by the cladoceran Daphnia pulex, suggesting decreasing diversity along with the trophic status. Overall, nutrient related variables appeared to have an important influence on the invertebrate community composition and diversity, the trophic state of the sites being linked with their exposure to geese guano. Other segregating variables included water color, presence/absence of fish, abundance of aquatic vegetation and lake depth. These results suggest that since most of these variables are climate-driven at a larger scale, the impacts of the ongoing climate change will have cumulative effects on aquatic ecosystems.

  2. Spectral albedo and transmittance of thin young Arctic sea ice

    Science.gov (United States)

    Taskjelle, Torbjørn; Hudson, Stephen R.; Granskog, Mats A.; Nicolaus, Marcel; Lei, Ruibo; Gerland, Sebastian; Stamnes, Jakob J.; Hamre, Børge

    2016-01-01

    Spectral albedo and transmittance in the range were measured on three separate dates on less than thick new Arctic sea ice growing on Kongsfjorden, Svalbard at , . Inherent optical properties, including absorption coefficients of particulate and dissolved material, were obtained from ice samples and fed into a radiative transfer model, which was used to analyze spectral albedo and transmittance and to study the influence of clouds and snow on these. Integrated albedo and transmittance for photosynthetically active radiation () were in the range 0.17-0.21 and 0.77-0.86, respectively. The average albedo and transmittance of the total solar radiation energy were 0.16 and 0.51, respectively. Values inferred from the model indicate that the ice contained possibly up to 40% brine and only 0.6% bubbles. Angular redistribution of solar radiation by clouds and snow was found to influence both the wavelength-integrated value and the spectral shape of albedo and transmittance. In particular, local peaks and depressions in the spectral albedo and spectral transmittance were found for wavelengths within atmospheric absorption bands. Simulated and measured transmittance spectra were within 5% for most of the wavelength range, but deviated up to 25% in the vicinity of , indicating the need for more optical laboratory measurements of pure ice, or improved modeling of brine optical properties in this near-infrared wavelength region.

  3. Effects on the atmospheric boundary layer of a solar eclipse in the Arctic

    Science.gov (United States)

    Sjöblom, Anna

    2010-05-01

    On 1 August 2008, a total solar eclipse took place in the Arctic and in Longyearbyen, the main settlement in the High Arctic archipelago of Svalbard (78° 13' N, 15° 37' E), the maximum solar coverage was 93%. The eclipse had a large impact on the atmospheric boundary layer and the local weather in general around Longyearbyen triggering a fog that lasted for three days. This fog grounded all air traffic to and from Svalbard and so in addition to the change in local weather, the eclipse also had economic and social consequences. Approximately 60% of Svalbard is covered with permanent ice and snow. Permafrost underlies most of the surface. In Longyearbyen, the midnight sun is present between 19 April and 23 August and so on the day of the eclipse the sun was about 30 degrees above the horizon at noon and 6 degrees above at midnight. A rare opportunity therefore occurred to study what happens when the sunlight is suddenly decreased after several months with no dark night. The maximum solar coverage at Longyearbyen took place at 10.41 Local Standard Time. The incoming shortwave radiation had then decreased from approximately 300 W m-2 before the start of the eclipse to 20 W m-2, i.e. less radiation than during a normal cloud free night at the same location at the same time of the year. Observations of turbulence and mean meteorological parameters were taken both over land and over a large fjord in the vicinity of Longyearbyen. In addition, cloud observations were recorded. Data have been analysed in detail from 31 July to 2 August, i.e., from one day before to one day after the eclipse. The simultaneous observations over land and over water showed that the atmospheric response was much faster and stronger over land than over water. Over land, the air temperature sank by 0.3-1.5°C, wind speed decreased, turbulent fluctuations were significantly reduced and the atmospheric stability changed from unstable to stable. Over the fjord, no clear minima in these parameters

  4. Seasonal fluxes and age of particulate organic carbon exported from Arctic catchments impacted by localized permafrost slope disturbances

    International Nuclear Information System (INIS)

    Projected warming is expected to alter the Arctic permafrost regime with potential impacts on hydrological fluxes of particulate organic carbon (POC) and sediment. Previous work has focused on large Arctic basins and revealed the important contribution of old carbon in river POC, but little is known about POC fluxes from smaller coastal watersheds, particularly where widespread postglacial raised marine sediments represent a potential source of old soil carbon that could be mobilized by permafrost disturbance. To evaluate these processes, the characteristics of POC, particulate nitrogen (PN) and suspended sediment transport from paired small coastal Arctic watersheds subject to recent permafrost disturbance were investigated at the Cape Bounty Arctic Watershed Observatory (CBAWO) in the Canadian High Arctic. Approximately 2% of the total suspended sediment load from both watersheds was composed of POC and the majority of the sediment and POC fluxes occurred during the spring snowmelt period. Radiocarbon analysis of POC indicates recent permafrost disturbances deliver substantially older POC to the aquatic system. Localized permafrost slope disturbances have a measurable influence on downstream POC age and dominate (estimated up to 78% of POC) sediment fluxes during summer baseflow. The elevation of disturbances and Holocene emergence data show limited age sensitivity of POC to the location of disturbance and suggest slope failures are likely to deliver carbon with a relatively similar age range to the aquatic system, regardless of landscape location. (paper)

  5. Correlation of stratigraphy, structure, metamorphism and intrusion in the Caledonian allochthons of East Greenland and Svalbard

    Science.gov (United States)

    Gee, David G.

    2014-05-01

    There are two main hypotheses for the relationships between the Greenland and Svalbard Caledonides. The one regards the Svalbard "terranes" to be a natural, along-strike (via the continental shelves) continuation of the northeast Greenland allochthons, with a minor component in southwest Spitsbergen of rock units with affinities to the Ellesmerian Orogen and Pearya. The other hypothesis regards Svalbard as an assembly of lithospheric fragments that have been moved thousands of kilometres along the axis of the Caledonide Orogen from more southerly latitudes. It has long been accepted that the Neoproterozoic to Early Paleozoic successions in the Caledonides of northeastern Greenland and on Nordaustlandet, eastern Svalbard, are closely comparable in stratigraphy, depositional environment and structure and are unambiguous parts of the Laurentian continental margin.Their close correlation provides the foundation for the interpretation that they were deposited adjacent to each other and subsequently separated by vast (1000 km plus) displacements on orogen-parallel sinistral transcurrent faults. Studies of their underlying metamorphic complexes (the Renlandian Orogen in the Hager Berg Allochthon of northeast Greenland and the Nordaustlandet Orogen of northeastern Svalbard), demonstrated that they had very similar histories: latest Mesoproterozoic to earliest Neoproterozoic siliciclastic deposition, followed by mid Tonian deformation, HT/LP metamorphism, migmatization and syn- to post-tectonic granite intrusion (c. 950-930 Ma). On Nordaustlandet, major unconformities and some calc-alkaline volcanics, separate this late Grenvillian "basement" complex from the overlying Cryogenian succession; in northeast Greenland, unconformity is inferred, but has yet to be demonstrated. Another aspect of the geological history of these two "terranes" is that their Caledonian tectonothermal histories are also remarkably similar, with early to mid Silurian HT/LP metamorphism and

  6. Screening of variable importance for optimizing electrodialytic remediation of heavy metals from polluted harbour sediments

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Lejon, Tore; Ottosen, Lisbeth M.;

    2015-01-01

    Using multivariate design and modelling, the optimal conditions for electrodialytic remediation (EDR) of heavy metals were determined for polluted harbour sediments from Hammerfest harbour located in the geographic Arctic region of Norway. The comparative importance of the variables, current dens...

  7. Modern sedimentation patterns in Lake El'gygytgyn, NE Russia, derived from surface sediment and inlet streams samples

    OpenAIRE

    Wennrich, V.; A. Francke; Dehnert, A.; O. Juschus; Leipe, T.; Vogt, C.; J. Brigham-Grette; P. S. Minyuk; Melles, M.; El'gygytgyn Science Party

    2013-01-01

    Lake El'gygytgyn/NE Russia holds a continuous 3.58 Ma sediment record, which is regarded as the most long-lasting climate archive of the terrestrial Arctic. Based on multi-proxy geochemical, mineralogical, and granulometric analyses of surface sediment, inlet stream and bedrock samples, supplemented by statistical methods, major processes influencing the modern sedimentation in the lake were investigated. Grain-size parameters and chemical elements linked to the input of feldspars from acidic...

  8. Sediment Load of Asian Rivers flowing into the Oceans and their Regional Variation

    Institute of Scientific and Technical Information of China (English)

    Liu Shuguang; Zheng Yonglai; Zhuge Zhengji; Li Congxian

    2002-01-01

    Study of the major Asian rivers discharge to the ocean reveals variations of their water discharges and sediment loads, and local characteristics of river sediment concentrations. On the basis of this, the Asian rivers fall into three regions, including Eurasia Arctic, East Asia, Southeast and South Asia Regions. The Eurasia Arctic Region is characterized by the lowest sediment concentration and load, while the East Asia Region is of the highest sediment concentration and higher sediment load, and the South-East and South Asia Region yields higher sediment concentration and highest sediment load.The sediment loads of these regions are mainly controlled by climate, geomorphology and tectonic activity. The Eurasia Arctic rivers with large basin areas and water discharge, drain low relief which consists of tundra sediment, thus causing the lowest sediment load. The East Asia rivers with small basin areas and lowest water discharges, drain extensive loess plateau, and transport most erodible loess material, which results in highest sediment concentration. The SE and South Asia rivers originating from the Tibet Plateau have large basin areas and the largest water discharges because of the Summer Monsoon and high rainfall influence, causing the highest sediment load.In Asia, tectonic motion of the Tibet Plateau plays an important role. Those large rivers originating from the Tibet Plateau transport about 50% of the world river sediment load to ocean annually, forming large estuaries and deltas, and consequently exerting a great influence on sedimentation in the coastal zone and shelves.

  9. Temporal and spatial variation in polychlorinated biphenyl chiral signatures of the Greenland shark (Somniosus microcephalus) and its arctic marine food web

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) chiral signatures were measured in Greenland sharks (Somniosus microcephalus) and their potential prey in arctic marine food webs from Canada (Cumberland Sound) and Europe (Svalbard) to assess temporal and spatial variation in PCB contamination at the stereoisomer level. Marine mammals had species-specific enantiomer fractions (EFs), likely due to a combination of in vivo biotransformation and direct trophic transfer. Greenland sharks from Cumberland Sound in 2007–2008 had similar EFs to those sharks collected a decade ago in the same location (PCBs 91, 136 and 149) and also similar to their conspecifics from Svalbard for some PCB congeners (PCBs 95, 136 and 149). However, other PCB EFs in the sharks varied temporally (PCB 91) or spatially (PCB 95), suggesting a possible spatiotemporal variation in their diets, since biotransformation capacity was unlikely to have varied within this species from region to region or over the time frame studied. -- Highlights: • Chiral PCB signatures were measured in Greenland sharks and their prey. • Marine mammals accumulated non-racemic PCBs from biotransformation and their diet. • Chiral PCB signatures were similar in sharks at two different arctic locations. • Some changes in chiral PCB signatures in sharks over a decade. -- PCB chiral signatures in Greenland sharks shift over time and space, likely in parallel with dietary variation

  10. Acquatorialities of the Arctic Region

    DEFF Research Database (Denmark)

    Harste, Gorm

    2013-01-01

    In order to describe the Arctic system I propose using a concept functionally equivalent to territoriality, namely aquatoriality. Whether communicating about territoriality or aquatoriality, concepts and delimitations are both contingent to forms of communication systems. I will distinguish between...... six communications systems that differentiated from each other could become involved in the new deals emerging around the Arctic. Apart of an economic communication code about the Arctic, a legal code, ecological communication codes, and tourist communication codes, I will cope with the military...

  11. Understanding volcanism at the PETM: Abundant volcanic ash layers in the Central Tertiary Basin of Spitsbergen, Svalbard

    Science.gov (United States)

    Jones, Morgan; Eliassen, Gauti; Svensen, Henrik; Jochmann, Malte; Friis, Bjarki; Jerram, Dougal; Planke, Sverre

    2014-05-01

    During the early Tertiary, Svalbard developed a fold-thrust belt on its western margin with an associated foreland basin in the central-south of what is now Spitsbergen. This Central Tertiary Basin (CTB) is a syn-orogenic sedimentary basin in a strike-slip regime. The CTB contains the ~1900 m thick Van Mijenfjorden group, a dominantly sandstone-shale succession that was deposited in a North-South extending basin. Sediments in this group display evidence of major transgressive-regressive cycles related to local tectonics and eustatic sea level change. This basin is ideal for study as it has been extensively cored for coal prospecting, allowing a suite of sedimentary logs across the basin to be considered. Prominent marker beds in this sedimentary sequence are 1-30 cm thick bentonites, formed from the chemical weathering of volcanic tuff deposits. In this study, we focus on 8 sedimentary logs across the CTB, spanning the Palaeocene to lower Eocene in age. Bentonites are common in the Palaeocene cores (Basilika and Grumantbyen formations), while rarer but still occasionally present in the Eocene Frysjaodden formation. The cores had between 3-12 observable bentonite layers that showed large variations in preservation and subsequent reworking. Roots and other finer organic material were common, especially when the bentonites were found next to coal seams. Geochemical affinities between ash layers were investigated to identify basin-wide depositional events, with the aim of elucidating the provenance of these ashes. This sedimentary sequence is of broader interest as it covers the Palaeocene-Eocene thermal maximum (PETM), an extreme global warming event driven by large releases to the atmosphere of CO2 and/or CH4, evidenced by a negative carbon isotope excursion in both the ocean and atmosphere. Potential sources include volcanism and associated gas release from intruded sediments, CH4 hydrate dissociation, and/or the oxidation of organic matter. These formations are

  12. The scavenging processes controlling the seasonal cycle in Arctic sulphate and black carbon aerosol

    Directory of Open Access Journals (Sweden)

    J. Browse

    2012-01-01

    Full Text Available The seasonal cycle in Arctic aerosol is typified by high concentrations of large aged anthropogenic particles transported from lower latitudes in the late Arctic winter and early spring followed by a sharp transition to low concentrations of locally sourced smaller particles in the summer. However, multi-model assessments show that many models fail to simulate a realistic cycle. Here, we use a global aerosol microphysics model and surface-level aerosol observations to understand how wet scavenging processes control the seasonal variation in Arctic black carbon (BC and sulphate aerosol concentrations. We show that the transition from high wintertime to low summertime Arctic aerosol concentrations is caused by the change from inefficient scavenging in ice clouds to the much more efficient scavenging in warm liquid clouds. This seasonal cycle is amplified further by the appearance of warm drizzling cloud in late spring and summer at a time when aerosol transport shifts mainly to low levels. Implementing these processes in a model greatly improves the agreement between the model and observations at the three Arctic ground-stations Alert, Barrow and Zeppelin Mountain on Svalbard. The SO4 model-observation correlation coefficient (R increases from: −0.33 to 0.71 at Alert (82.5° N, from −0.16 to 0.70 at Point Barrow (71.0° N and from −0.42 to 0.40 at Zeppelin Mountain (78° N while, the BC model-observation correlation coefficient increases from −0.68 to 0.72 at Alert and from −0.42 to 0.44 at Barrow. Observations at three marginal Arctic sites (Janiskoski, Oulanka and Karasjok indicate a far weaker aerosol seasonal cycle, which we show is consistent with the much smaller seasonal changes in ice clouds compared to the higher latitude sites. Our results suggest that the seasonal cycle in Arctic aerosol is driven by temperature-dependent scavenging processes that may be susceptible to modification in a future climate.

  13. Arctic Ocean circulation during the anoxic Eocene Azolla event

    Science.gov (United States)

    Speelman, Eveline; Sinninghe Damsté, Jaap; März, Christian; Brumsack, Hans; Reichart, Gert-Jan

    2010-05-01

    The Azolla interval, as encountered in Eocene sediments from the Arctic Ocean, is characterized by organic rich sediments ( 4wt% Corg). In general, high levels of organic matter may be caused by increased productivity, i.e. extensive growth of Azolla, and/or enhanced preservation of organic matter, or a combination of both. Anoxic (bottom) water conditions, expanded oxygen minimum zones, or increased sedimentation rates all potentially increase organic matter preservation. According to plate tectonic, bathymetric, and paleogeographic reconstructions, the Arctic Ocean was a virtually isolated shallow basin, with one possible deeper connection to the Nordic Seas represented by a still shallow Fram Strait (Jakobsson et al., 2007), hampering ventilation of the Arctic Basin. During the Azolla interval surface waters freshened, while at the same time bottom waters appear to have remained saline, indicating that the Arctic was highly stratified. The restricted ventilation and stratification in concert with ongoing export of organic matter most likely resulted in the development of anoxic conditions in the lower part of the water column. Whereas the excess precipitation over evaporation maintained the freshwater lid, sustained input of Nordic Sea water is needed to keep the deeper waters saline. To which degree the Arctic Ocean exchanged with the Nordic Seas is, however, still largely unknown. Here we present a high-resolution trace metal record (ICP-MS and ICP-OES) for the expanded Early/Middle Eocene section capturing the Azolla interval from Integrated Ocean Drilling Program (IODP) Expedition 302 (ACEX) drilled on the Lomonosov Ridge, central Arctic Ocean. Euxinic conditions throughout the interval resulted in the efficient removal of redox sensitive trace metals from the water column. Using the sedimentary trace metal record we also constrained circulation in the Arctic Ocean by assessing the relative importance of trace metal input sources (i.e. fluvial, eolian, and

  14. Disparities in Arctic Health

    Centers for Disease Control (CDC) Podcasts

    2008-02-04

    Life at the top of the globe is drastically different. Harsh climate devoid of sunlight part of the year, pockets of extreme poverty, and lack of physical infrastructure interfere with healthcare and public health services. Learn about the challenges of people in the Arctic and how research and the International Polar Year address them.  Created: 2/4/2008 by Emerging Infectious Diseases.   Date Released: 2/20/2008.

  15. Summer Arctic sea fog

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Synchronous or quasi-synchronous sea-land-air observations were conducted using advanced sea ice, atmospheric and marine instruments during China' s First Arctic Expedition. Based on the Precious data from the expedition, it was found that in the Arctic Ocean, most part of which is covered with ice or is mixed with ice, various kinds of sea fog formed such as advection fog, radiation fog and vapor fog. Each kind has its own characteristic and mechanics of creation. In the southern part of the Arctic Ocean, due to the sufficient warm and wet flow there, it is favorable for advection fog to form,which is dense and lasts a long time. On ice cap or vast floating ice, due to the strong radiation cooling effect, stable radiating fog is likely to form. In floating ice area there forms vapor fog with the appearance of masses of vapor from a boiling pot, which is different from short-lasting land fog. The study indicates that the reason why there are many kinds of sea fog form in the Arctic Ocean is because of the complicated cushion and the consequent sea-air interaction caused by the sea ice distribution and its unique physical characteristics. Sea fog is the atmospheric phenomenon of sea-air heat exchange. Especially, due to the high albedo of ice and snow surface, it is diffcult to absorb great amount of solar radiation during the polar days. Besides, ice is a poor conductor of heat; it blocks the sea-air heat exchange.The sea-air exchange is active in floating ice area where the ice is broken. The sea sends heat to the atmosphere in form of latent heat; vapor fog is a way of sea-air heat exchange influencing the climate and an indicator of the extent of the exchange. The study also indicates that the sea also transports heat to the atmosphere in form of sensible heat when vapor fog occurs.

  16. Biological productivity and carbon cycling in the Arctic Ocean

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Primary production, bacterial production, particulate organic carbon fluxes and organic carbon burial rates were quantified during the summer period of 1999 in the Arctic Ocean via 14C uptake, 3H uptake, 234Th/238U disequilibrium and 210Pbex dating, respectively. The integrated primary production in the water column was as high as 197 mmolC/(m2@d) in the Chukchi shelf and was 3.8 mmolC/(m2@d) in the Canada Basin. These rates are higher than those reported previously. The ratios of bacterial production to primary production in the study region were higher than 0.5, indicating that microbial activity is not depressed but important in cold Arctic waters. 234Th/238U disequilibria were evident at the station in the Canada Basin. The presence of significant 234Th deficiency suggested that scavenging and removal processes are also important to biogeochemical cycles of trace elements in the Arctic Ocean. Particulate organic carbon export flux was estimated to be 1.0 mmolC/(m2@d). Measurements of sediment excess 210Pb profile in the Chukchi shelf allowed us to estimate the amount of organic carbon buried in the bottom sediment, which ranged from 25 to 35 mmolC/(m2@d) and represented about 59%-82% of the mean primary production in the euphotic zone. Overall, our results indicated that the Arctic Ocean has active carbon cycling and is not a biological desert as previously believed. Therefore, the Arctic Ocean may play an important role in the global carbon cycle and climate change.

  17. Sampling and quantifying oil in coarse sediments

    International Nuclear Information System (INIS)

    The importance of sample size in sampling natural sediments for contamination is discussed. It is shown that analytical results can vary widely if samples are too small to provide a realistic distribution of the grain sizes of the beach sediment with the normally high variability in natural sediment grain size. To guard against under or overestimation of contaminant concentration in the Svalbard field trials, samples greater than 1.5 litre were collected and extracted. In addition to large sample size, care was also taken to collect a vertical profile of equal proportions. Depth of oil penetration and accretion of surface sediments were also taken into account. Cross-shore differences in oil removal were avoided by collecting samples along a relatively narrow along-shore band within the inter-tidal zone, and edge effects were minimized by maintaining the sample exclusion zones within the oiled plot. The number of samples per plot is of obvious significance. The best indicator that the sample design was valid is the fact that, for some plots and treatments, differences in concentration could be defined at the 90 per cent confidence level

  18. Regional aerosol optical properties and radiative impact of the extreme smoke event in the European Arctic in spring 2006

    Directory of Open Access Journals (Sweden)

    C. Lund Myhre

    2007-11-01

    Full Text Available In spring 2006 a special meteorological situation occurred in the European Arctic region giving record high levels of air pollution. The synoptic situation resulted in extensive transport of pollution predominantly from agricultural fires in Eastern Europe into the Arctic region and record high air-pollution levels were measured at the Zeppelin observatory at Ny-Ålesund (78°54' N, 11°53' E in the period from 25 April to 12 May. In the present study we investigate the optical properties of the aerosols from this extreme event and we estimate the radiative forcing of this episode.

    We examine the aerosol optical properties from the source region and into the European Arctic and explore the evolution of the episode and the changes in the optical properties. A number of sites in Eastern Europe, Northern Scandinavia and Svalbard are included in the study. The observations show that the maximum AOD was from 2–3 May at all sites and varies from 0.52 to 0.87, and the corresponding Ångstrøm exponent was relatively large. Lidar measurements from Minsk, ALOMAR (Arctic Lidar Observatory for Middle Atmosphere Research at Andenes and Ny-Ålesund show that the aerosol layer was below 3 km at all sites the height is decreasing from the source region and into the Arctic. For the AERONET sites included (Minsk, Toravere, Hornsund we have further studied the evolution of the aerosol size. The single scattering albedo at Svalbard is provided for two sites; Ny-Ålesund and Hornsund. Importantly the calculated single scattering albedo based on the aerosol chemical composition and size distribution from Ny-Ålesund and the AERONET measurements at Hornsund are consistent. We have found strong agreement between the satellite daily MODIS AOD and the ground-based AOD observations. This agreement is crucial for accurate radiative forcing calculations. We calculate a strong negative radiative forcing for the most polluted days employing the analysed

  19. Climate sensitivity to Arctic seaway restriction during the early Paleogene

    Science.gov (United States)

    Roberts, Christopher D.; LeGrande, Allegra N.; Tripati, Aradhna K.

    2009-09-01

    The opening and closing of ocean gateways affects the global distribution of heat, salt, and moisture, potentially driving climatic change on regional to global scales. Between 65 and 45 million years ago (Ma), during the early Paleogene, exchange between the Arctic and global oceans occurred through two narrow and shallow seaways, the Greenland-Norway seaway and the Turgai Strait. Sediments from the Arctic Ocean suggest that, during this interval, the surface ocean was warm, brackish, and episodically enabled the freshwater fern Azolla to bloom. The precise mechanisms responsible for the development of these conditions in the Paleogene Arctic remain uncertain. Here we show results from an isotope-enabled, atmosphere-ocean general circulation model, which indicate that Northern Hemisphere climate would have been very sensitive to the degree of oceanic exchange through the Arctic seaways. We also present modelled estimates of seawater and calcite δ18O for the Paleogene. By restricting these seaways, we simulate freshening of the surface Arctic Ocean to ~ 6 psu and warming of sea-surface temperatures by 2 °C in the North Atlantic and 5-10 °C in the Labrador Sea. Our results may help explain the occurrence of low-salinity tolerant taxa in the Arctic Ocean during the Eocene and provide a mechanism for enhanced warmth in the north western Atlantic. We propose that the formation of a volcanic land-bridge between Greenland and Europe could have caused increased ocean convection and warming of intermediate waters in the Atlantic. If true, this result is consistent with the theory that bathymetry changes may have caused thermal destabilisation of methane clathrates and supports a tectonic trigger hypothesis for the Paleocene Eocene Thermal Maximum (PETM).

  20. Geological Structure and History of the Arctic Ocean

    Science.gov (United States)

    Petrov, Oleg; Morozov, Andrey; Shokalsky, Sergey; Sobolev, Nikolay; Kashubin, Sergey; Pospelov, Igor; Tolmacheva, Tatiana; Petrov, Eugeny

    2016-04-01

    New data on geological structure of the deep-water part of the Arctic Basin have been integrated in the joint project of Arctic states - the Atlas of maps of the Circumpolar Arctic. Geological (CGS, 2009) and potential field (NGS, 2009) maps were published as part of the Atlas; tectonic (Russia) and mineral resources (Norway) maps are being completed. The Arctic basement map is one of supplements to the tectonic map. It shows the Eurasian basin with oceanic crust and submerged margins of adjacent continents: the Barents-Kara, Amerasian ("Amerasian basin") and the Canada-Greenland. These margins are characterized by strained and thinned crust with the upper crust layer, almost extinct in places (South Barents and Makarov basins). In the Central Arctic elevations, seismic studies and investigation of seabed rock samples resulted in the identification of a craton with the Early Precambrian crust (near-polar part of the Lomonosov Ridge - Alpha-Mendeleev Rise). Its basement presumably consists of gneiss granite (2.6-2.2 Ga), and the cover is composed of Proterozoic quartzite sandstone and dolomite overlain with unconformity and break in sedimentation by Devonian-Triassic limestone with fauna and terrigenous rocks. The old crust is surrounded by accretion belts of Timanides and Grenvillides. Folded belts with the Late Precambrian crust are reworked by Caledonian-Ellesmerian and the Late Mesozoic movements. Structures of the South Anuy - Angayucham ophiolite suture reworked in the Early Cretaceous are separated from Mesozoides proper of the Pacific - Verkhoyansk-Kolyma and Koryak-Kamchatka belts. The complicated modern ensemble of structures of the basement and the continental frame of the Arctic Ocean was formed as a result of the conjugate evolution and interaction of the three major oceans of the Earth: Paleoasian, Paleoatlantic and Paleopacific.

  1. Basalt weathering in an Arctic Mars-analog site

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    Yesavage, Tiffany; Thompson, Aaron; Hausrath, Elisabeth M.; Brantley, Susan L.

    2015-07-01

    The martian surface has undergone chemical and physical weathering in the past, and these processes may continue intermittently today. To explore whether martian rocks are likely to retain features indicative of weathering, we investigated how basaltic material weathers on Earth. Specifically, we investigated weathering of a Quaternary-aged basaltic flow at the Sverrefjell volcano in Svalbard, above the Arctic Circle. This flow weathered since deglaciation under cold, dry (characterized the mineralogical and morphological properties using electron microscopy (EM), X-ray diffraction (XRD), infrared (IR) spectroscopy and selective chemical dissolution. In addition, we ran colloidal dispersion, wetting/drying, and freeze/thaw experiments. In the regolith, we observed concentrations of short-range ordered (SRO) phases similar to those observed in warmer, wetter volcanic ash soils. IR and EM analyses of the clay-sized fraction were consistent with allophane as the predominant secondary phase. Selective chemical extractions targeting SRO phases indicated lower Al/Si ratios than those observed in volcanic soils reported in warmer localities, which we attribute to Si-rich allophane and/or abundant Si-rich rock coatings. The oxic circumneutral-pH colloidal dispersion experiments mobilized Al, Fe and Ti primarily as 260-415 nm particles and Ca, Mg and Na as solutes. Si was lost both in the colloidal and dissolved forms. Dispersed colloids likely contain allophane and ferrihydrite. Under anoxic conditions, dissolution of Fe oxide cements also released fines. The experiments help to explain elemental loss from the clay-sized regolith fraction at Svalbard: observed depletions in Ca, K, Mg and Na were likely due to solute loss, while particle-reactive Al, Fe, Si and Ti were mostly retained. Wetting/drying was observed to be as effective as freeze/thaw in driving material loss. It is thus possible that cyclic adsorption of water onto basaltic rocks in this dry climate may result

  2. Supraglacial dust and debris: geochemical compositions from glaciers in Svalbard, southern Norway, Nepal and New Zealand

    Directory of Open Access Journals (Sweden)

    K. A. Casey

    2012-02-01

    Full Text Available Alpine glacier samples were collected in four contrasting regions to measure supraglacial dust and debris geochemical composition and quantify regional variability. A total of 70 surface glacier ice, snow and debris samples were collected in Svalbard, southern Norway, Nepal and New Zealand. Trace elemental abundances in snow and ice samples were measured via inductively coupled plasma mass spectrometry (ICP-MS. Supraglacial debris mineral, bulk oxide and trace element composition were determined via X-ray diffraction (XRD and X-ray fluorescence spectroscopy (XRF. A total of 45 major, trace and rare earth elements and 10 oxide compound abundances are reported. Elemental abundances revealed sea salt aerosol and metal enrichment in Svalbard, low levels of crustal dust and marine influences to southern Norway, high crustal dust and anthropogenic enrichment in the Khumbu Himalayas, and sulfur and metals attributed to quiescent degassing and volcanic activity in northern New Zealand. Rare earth element and Al/Ti elemental ratios demonstrated distinct provenance of particulates in each study region. Ca/S elemental ratio data showed seasonal denudation in Svalbard and southern Norway. Ablation season atmospheric particulate transport trajectories were mapped in each of the study regions and suggest provenance pathways. The in situ data presented provides first-order glacier surface geochemical variability as measured in the four diverse alpine glacier regions. The surface glacier geochemical data set is available from the PANGAEA database at doi:10.1594/PANGAEA.773951. This geochemical surface glacier data is relevant to glaciologic ablation rate understanding as well as satellite atmospheric and land-surface mapping techniques currently in development.

  3. Chemical denudation and the role of sulfide oxidation at Werenskioldbreen, Svalbard

    Science.gov (United States)

    Stachnik, Łukasz; Majchrowska, Elżbieta; Yde, Jacob C.; Nawrot, Adam P.; Cichała-Kamrowska, Katarzyna; Ignatiuk, Dariusz; Piechota, Agnieszka

    2016-07-01

    This study aims to determine the rate of chemical denudation and the relationships between dominant geochemical reactions operating in the proglacial and subglacial environments of the polythermal glacier Werenskioldbreen (SW Svalbard) during an entire ablation season. Water sampling for major ion chemistry was performed at a proglacial hydrometric station and from subglacial outflows from May to September 2011. These data were combined with measurements of discharge and supraglacial ablation rates. The slopes and intercepts in best-fit regressions of [*Ca2+ + *Mg2+ vs. *SO42-] and [HCO3- vs. *SO42-] in meltwater from ice-marginal subglacial channels were close to the stoichiometric parameters of sulfide oxidation and simple hydrolysis coupled to carbonate dissolution (*concentrations corrected for input of sea-salt). This shows that these relationships predominates the meltwater chemistry. Our findings also show that sulfide oxidation is a better indicator of the configuration of subglacial drainage systems than, for instance, Na+ and K+. In the proglacial area and in sub-artesian outflows, the ion associations represent sulfide oxidation but other processes such as ion exchange and dissolution of Ca and Mg efflorescent salts may also contribute to the solute variations. These processes may cause enhanced fluxes of Ca2+ and HCO3- from glacierized basins during the early ablation and peak flow seasons as the proglacial salts re-dissolve. The overall chemical denudation rate in the basin for 2011 (ranging from 1601 to 1762 meq m-2 yr-1 (121.9 to 132.2 t km-2 yr-1)) was very high when compared to other Svalbard valley glaciers suggesting that the high rate of chemical denudation was mostly caused by the high rates of discharge and ablation. Chemical weathering intensities (876 and 964 meq m-3 yr-1) exceeded previously reported intensities in Svalbard.

  4. BrO in the arctic atmosphere in spring 2007

    Science.gov (United States)

    Prados Roman, C.; Butz, A.; Deutschmann, T.; Dorf, M.; Kritten, L.; Minikin, A.; Platt, U.; Schlager, H.; Pfeilsticker, K.

    2009-12-01

    Within the ASTAR 2007 campaign ("Arctic Study of Tropospheric Aerosol, Clouds and Radiation", IPY 2007/8) that took place in Svalbard (78°N) in April 2007, spectroscopic limb scattered skylight measurements were performed from aboard the DLR (Deutsches Zentrum für Luft- und Raumfahrt) Falcon aircraft. By applying the Differential Optical Absorption Spectroscopy technique (DOAS), we attempted to detect the mixing ratio vertical profiles of O3, NO2, BrO, OClO, IO, OIO, HONO, C2H2O2, CH2O, H2O and O4 from the boundary layer (BL), up to the lowermost stratosphere within the arctic atmosphere. Here we will focus on the detection of BrO and its vertical profile retrieval. Even though the limb DOAS measurements are extremely sensitive regarding the detection of trace gases (i.e., limit for the BrO detection ~1 pptv), the challenge of the profile retrieval comes with dealing appropriately with the actual Radiative Transfer (RT) processes in the atmosphere (e.g., Rayleigh and Mie scattering). Here, our approach is based on the retrieval of the Mie scattering extinction profile from measured radiance ratios, validated using in-situ measured aerosol and cloud particle concentrations. This information is then fed into forward RT calculations in order to obtain the proper kernel for mathematical inversion of the measured slant column absorption. The inverted O4 profile is used as a proof of the viability of this method and, finally, the vertical profile of the BrO mixing ratio is retrieved. In general, results of the ASTAR 2007 flights indicate that bromine explosions and ozone depletion events (ODEs) were occurring above the arctic first-year sea ice in non-hazy conditions in April 2007. In particular, the flight on the 8th April 2007 shows largely depleted O3 (environment will be presented. In addition, the source of our BrO data will be discussed (e.g. BL or stratospheric signal, etc).

  5. Simultaneous profiling of the Arctic Atmospheric Boundary Layer

    Science.gov (United States)

    Mayer, S.; Jonassen, M.; Reuder, J.

    2009-09-01

    The structure of the Arctic atmospheric boundary layer (AABL) and the heat and moisture fluxes between relatively warm water and cold air above non-sea-ice-covered water (such as fjords, leads and polynyas) are of great importance for the sensitive Arctic climate system (e.g. Andreas and Cash, 1999). So far, such processes are not sufficiently resolved in numerical weather prediction (NWP) and climate models (e.g. Tjernström et al., 2005). Especially for regions with complex topography as the Svalbard mountains and fjords the state and diurnal evolution of the AABL is not well known yet. Knowledge can be gained by novel and flexible measurement techniques such as the use of an unmanned aerial vehicle (UAV). An UAV can perform vertical profiles as well as horizontal surveys of the mean meteorological parameters: temperature, relative humidity, pressure and wind. A corresponding UAV, called Small Unmanned Meteorological Observer (SUMO), has been developed at the Geophysical Institute at the University of Bergen in cooperation with Müller Engineering (www.pfump.org) and the Paparazzi Project (http://paparazzi.enac.fr). SUMO has been used under Arctic conditions at Longyear airport, Spitsbergen in March/April 2009. Besides vertical profiles up to 1500 m and horizontal surveys at flight levels of 100 and 200 m, SUMO could measure vertical profiles for the first time simultaneously in a horizontal distance of 1 km; one over the ice and snow-covered land surface and the other one above the open water of Isfjorden. This has been the first step of future multiple UAV operations in so called "swarms” or "flocks”. With this, corresponding measurements of the diurnal evolution of the AABL can be achieved with minimum technical efforts and costs. In addition, the Advanced Research Weather Forecasting model (AR-WRF version 3.1) has been run in high resolution (grid size: 1 km). First results of a sensitivity study where ABL schemes have been tested and compared with

  6. Chenophila nanseni sp. n. (Acari: Syringophilidae parasitising the barnacle goose in Svalbard

    Directory of Open Access Journals (Sweden)

    Skoracki Maciej

    2016-03-01

    Full Text Available A new species, Chenophila nanseni sp. n., collected from covert quills of the barnacle goose Branta leucopsis (Anseriformes: Anatidae in Svalbard (Spitsbergen is described and female polymorphism is recorded in this species. In syringophilids this phenomenon was known only for representatives of the genus Stibar