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Sample records for arctic east siberia

  1. Arctic East Siberia had a lower latitude in the Pleistocene

    OpenAIRE

    Willy Woelfli; Walter Baltensperger

    2006-01-01

    Remains of mammoths in Arctic East Siberia, where there is not sufficient sunlight over the year for the growth of the plants on which these animals feed, indicate that the latitude of this region was lower before the end of the Pleistocene than now. Reconstructing this geographic pole shift, we introduce a massive object, which moved in an extremely eccentric orbit and was hot from tidal work and solar radiation. Evaporation produced a disk-shaped cloud of ions around the Sun. This cloud par...

  2. Arctic East Siberia had a lower latitude in the Pleistocene

    CERN Document Server

    Wölfli, W

    2006-01-01

    In Arctic East Siberia many remains of mammoths have been found. In this region there is not sufficient sunlight over the year to allow for the growth of the plants on which these animals feed. Consequently the latitude of these regions must have been lower before the end of the Pleistocene than at present. It is a challenge to reconstruct this geographic shift of the poles in a manner compa- tible with known facts. A possible sequence of events is described here. It as- sumes an additional planet, which must since have disappeared. This is possible, if it moved in an extremely eccentric orbit and was hot as a result of tidal work and solar radiation. During a few million years evaporation of this planet led to a disk-shaped cloud of ions moving around the Sun. This cloud partially shielded the Earth from the solar radiation, producing the alteration of cold and warm periods characterizing the Pleistocene. The degree of shielding is sensitive to the inclination of Earth's orbit, which has a period of 100000 y...

  3. Arctic East Siberia had a lower latitude in the Pleistocene

    Directory of Open Access Journals (Sweden)

    Willy Woelfli

    2007-06-01

    Full Text Available Remains of mammoths in Arctic East Siberia, where there is not sufficient sunlight over the year for the growth of the plants on which these animals feed, indicate that the latitude of this region was lower before the end of the Pleistocene than now. Reconstructing this geographic pole shift, we introduce a massive object, which moved in an extremely eccentric orbit and was hot from tidal work and solar radiation. Evaporation produced a disk-shaped cloud of ions around the Sun. This cloud partially shielded the solar radiation, producing the cold and warm periods characterizing the Pleistocene. The shielding depends on the inclination of Earth's orbit, which has a period of 100. 000 years. The cloud builds up to a point where inelastic particle collisions induce its collapse The resulting near-periodic time dependence resembles that of Dansgaard-Oeschger events. The Pleistocene ended when the massive object had a close encounter with the Earth, which suffered a one per mil extensional deformation. While the deformation relaxed to an equilibrium shape in one to several years, the globe turned relative to the rotation axis: The North Pole moved from Greenland to the Arctic Sea. The massive object split into fragments, which evaporated.Na Sibéria Oriental Ártica, onde há sobras de mamutes, a luzsolar durante o ano é insuficiente para sustentar as plantas que alimentam esses animais. Isto prova que a latitude dessas regiões era menor durante o Pleistoceno. Reconstruindo esse deslocamento geográfico dos pólos introduzimos um planeta adicional numa órbita tão excêntrica que a energia da maré e da radiação solar o esquentou. A sua evaporação criava em torno do sol uma nuvem de íons que espalhava a radiação solar e assim causava os períodos quentes e frios do Pleistoceno. O efeito depende da inclinação da órbita da terra, que varia com um período de 100. 000 anos. Quase periodicamente anuvem se formava até o ponto em que as colis

  4. On the change of latitude of Arctic East Siberia at the end of the Pleistocene

    CERN Document Server

    Wölfli, W

    2007-01-01

    Mammoths lived in Arctic East Siberia. In this region there is not sufficient sunlight over the year for the growth of the plants on which these animals feed. Therefore the latitude of this region was lower before the end of the Pleistocene. As the cause of this geographic pole shift, we postulate a massive object, which moved in an extremely eccentric orbit and was hot from tidal work and solar radiation. Evaporation produced a disk-shaped cloud of ions around the Sun. This cloud partially shielded the solar radiation, producing the cold and warm periods that characterize the Pleistocene. The shielding depends on the inclination of Earth's orbit, which has a period of 100'000 years. The cloud builds up to a density at which inelastic particle collisions induce its collapse The resulting near-periodic time dependence resembles that of Dansgaard-Oeschger events. During cold periods fine grained inclusions were deposited into the ice. The Pleistocene ended when the massive object had a close encounter with the ...

  5. Food and water security issues in Russia II: Water security in general population of Russian Arctic, Siberia and Far East, 2000–2011

    OpenAIRE

    Dudarev, Alexey A.; Eugenia V. Dushkina; Sladkova, Yuliya N; Alloyarov, Pavel R.; Chupakhin, Valeriy S.; Dorofeyey, Vitaliy M.; Tatijana A. Kolesnikova; Fridman, Kirill B.; Evengård, Birgitta; Nilsson, Lena Maria

    2013-01-01

    Background. Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies.Study design and methods. Uniform water security indicators collected from Russian official statistical sources for th...

  6. Food and water security issues in Russia III: food- and waterborne diseases in the Russian Arctic, Siberia and the Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-12-01

    Full Text Available Background . The food- and waterborne disease situation in Russia requires special attention. Poor quality of centralized water supplies and sewage systems, biological and chemical contamination of drinking water, as well as contamination of food products, promote widespread infectious diseases, significantly exceeding nationwide rates in the population living in the two-thirds of Russian northern territories. Objectives. The general aim was to assess the levels of food- and waterborne diseases in selected regions of Russian Arctic, Siberia and the Far East (for the period 2000–2011, and to compare disease levels among regions and with national levels in Russia. Study design and methods . This study is the first comparative assessment of the morbidity in these fields of the population of 18 selected regions of Russian Arctic, Siberia and the Far East, using official statistical sources. The incidences of infectious and parasitic food- and waterborne diseases among the general population (including indigenous peoples have been analyzed in selected regions (per 100,000 of population, averaged for 2000–2011. Results . Among compulsory registered infectious and parasitic diseases, there were high rates and widespread incidences in selected regions of shigellosis, yersiniosis, hepatitis A, tularaemia, giardiasis, enterobiasis, ascariasis, diphyllobothriasis, opistorchiasis, echinococcosis and trichinellosis. Conclusion . Incidences of infectious and parasitic food- and waterborne diseases in the general population of selected regions of the Russian Arctic, Siberia and the Far East (2000–2011 are alarmingly high. Parallel solutions must be on the agenda, including improvement of sanitary conditions of cities and settlements in the regions, modernization of the water supply and of the sewage system. Provision and monitoring of the quality of the drinking water, a reform of the general healthcare system and the epidemiological surveillance

  7. Food and water security issues in Russia I: food security in the general population of the Russian Arctic, Siberia and the Far East, 2000–2011

    Science.gov (United States)

    Dudarev, Alexey A.; Alloyarov, Pavel R.; Chupakhin, Valery S.; Dushkina, Eugenia V.; Sladkova, Yuliya N.; Dorofeyev, Vitaliy M.; Kolesnikova, Tatijana A.; Fridman, Kirill B.; Nilsson, Lena Maria; Evengård, Birgitta

    2013-01-01

    Background Problems related to food security in Russian Arctic (dietary imbalance, predominance of carbohydrates, shortage of milk products, vegetables and fruits, deficit of vitamins and microelements, chemical, infectious and parasitic food contamination) have been defined in the literature. But no standard protocol of food security assessment has been used in the majority of studies. Objectives Our aim was to obtain food security indicators, identified within an Arctic collaboration, for selected regions of the Russian Arctic, Siberia and the Far East, and to compare food safety in these territories. Study design and methods In 18 regions of the Russian Arctic, Siberia and the Far East, the following indicators of food security were analyzed: food costs, food consumption, and chemical and biological food contamination for the period 2000–2011. Results Food costs in the regions are high, comprising 23–43% of household income. Only 4 out of 10 food groups (fish products, cereals, sugar, plant oil) are consumed in sufficient amounts. The consumption of milk products, eggs, vegetables, potatoes, fruits (and berries) is severely low in a majority of the selected regions. There are high levels of biological contamination of food in many regions. The biological and chemical contamination situation is alarming, especially in Chukotka. Only 7 food pollutants are under regular control; among pesticides, only DDT. Evenki AO and Magadan Oblast have reached peak values in food contaminants compared with other regions. Mercury in local fish has not been analyzed in the majority of the regions. In 3 regions, no monitoring of DDT occurs. Aflatoxins have not been analyzed in 5 regions. Nitrates had the highest percentage in excess of the hygienic threshold in all regions. Excesses of other pollutants in different regions were episodic and as a rule not high. Conclusion Improvement of the food supply and food accessibility in the regions of the Russian Arctic, Siberia and the

  8. Food and water security issues in Russia I: food security in the general population of the Russian Arctic, Siberia and the Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-10-01

    Full Text Available Background. Problems related to food security in Russian Arctic (dietary imbalance, predominance of carbohydrates, shortage of milk products, vegetables and fruits, deficit of vitamins and microelements, chemical, infectious and parasitic food contamination have been defined in the literature. But no standard protocol of food security assessment has been used in the majority of studies. Objectives. Our aim was to obtain food security indicators, identified within an Arctic collaboration, for selected regions of the Russian Arctic, Siberia and the Far East, and to compare food safety in these territories. Study design and methods. In 18 regions of the Russian Arctic, Siberia and the Far East, the following indicators of food security were analyzed: food costs, food consumption, and chemical and biological food contamination for the period 2000–2011. Results. Food costs in the regions are high, comprising 23–43% of household income. Only 4 out of 10 food groups (fish products, cereals, sugar, plant oil are consumed in sufficient amounts. The consumption of milk products, eggs, vegetables, potatoes, fruits (and berries is severely low in a majority of the selected regions. There are high levels of biological contamination of food in many regions. The biological and chemical contamination situation is alarming, especially in Chukotka. Only 7 food pollutants are under regular control; among pesticides, only DDT. Evenki AO and Magadan Oblast have reached peak values in food contaminants compared with other regions. Mercury in local fish has not been analyzed in the majority of the regions. In 3 regions, no monitoring of DDT occurs. Aflatoxins have not been analyzed in 5 regions. Nitrates had the highest percentage in excess of the hygienic threshold in all regions. Excesses of other pollutants in different regions were episodic and as a rule not high. Conclusion. Improvement of the food supply and food accessibility in the regions of the Russian

  9. Food and water security issues in Russia II: Water security in general population of Russian Arctic, Siberia and Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-12-01

    Full Text Available Background . Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies. Study design and methods . Uniform water security indicators collected from Russian official statistical sources for the period 2000–2011 were used for comparison for 18 selected regions in the Russian Arctic, Siberia and Far East. The following indicators of water security were analyzed: water consumption, chemical and biological contamination of water reservoirs of Categories I and II of water sources (centralized – underground and surface, and non-centralized and of drinking water. Results . Water consumption in selected regions fluctuated from 125 to 340 L/person/day. Centralized water sources (both underground and surface sources are highly contaminated by chemicals (up to 40–80% and biological agents (up to 55% in some regions, mainly due to surface water sources. Underground water sources show relatively low levels of biological contamination, while chemical contamination is high due to additional water contamination during water treatment and transportation in pipelines. Non-centralized water sources are highly contaminated (both chemically and biologically in 32–90% of samples analyzed. Very high levels of chemical contamination of drinking water (up to 51% were detected in many regions, mainly in the north-western part of the Russian Arctic. Biological contamination of drinking water was generally much lower (2.5–12% everywhere except Evenki AO (27%, and general and thermotolerant coliform bacteria predominated in drinking water samples from all regions (up to 17.5 and 12.5%, correspondingly. The presence of other agents was much lower: Coliphages

  10. Bird orientation at high latitudes: flight routes between Siberia and North America across the Arctic Ocean

    Science.gov (United States)

    Alerstam; Gudmundsson

    1999-12-22

    Bird migration and orientation at high latitudes are of special interest because of the difficulties associated with different compass systems in polar areas and because of the considerable differences between flight routes conforming to loxodromes (rhumblines) or orthodromes (great circle routes). Regular and widespread east-north-east migration of birds from the northern tundra of Siberia towards North America across the Arctic Ocean (without landmark influences) were recorded by ship-based tracking radar studies in July and August. Field observations indicated that waders, including species such as Phalaropusfulicarius and Calidris melanotos, dominated, but also terns and skuas may have been involved. Analysis of flight directions in relation to the wind showed that these movements are not caused by wind drift. Assuming possible orientation principles based on celestial or geomagnetic cues, different flight trajectories across the Arctic Ocean were calculated: geographical loxodromes, sun compass routes, magnetic loxodromes and magnetoclinic routes. The probabilities of these four alternatives are evaluated on the basis of both the availability of required orientation cues and the predicted flight paths. This evaluation supports orientation along sun compass routes. Because of the longitudinal time displacement sun compass routes show gradually changing compass courses in close agreement with orthodromes. It is suggested that an important migration link between Siberia and North American stopover sites 1000-2500km apart across the Arctic Ocean has evolved based on sun compass orientation along orthodrome-like routes. PMID:10693821

  11. Comparative analysis of marine paleogene sections and biota from West Siberia and the Arctic Region

    Science.gov (United States)

    Akhmet'ev, M. A.; Zaporozhets, N. I.; Iakovleva, A. I.; Aleksandrova, G. N.; Beniamovsky, V. N.; Oreshkina, T. V.; Gnibidenko, Z. N.; Dolya, Zh. A.

    2010-12-01

    The analysis of the main biospheric events that took place in West Siberia and the Arctic region during the Early Paleogene revealed the paleogeographic and paleobiogeographic unity of marine sedimentation basins and close biogeographic relations between their separate parts. Most biotic and abiotic events of the first half of the Paleogene in the Arctic region and West Siberia were synchronous, unidirectional, and interrelated. Shelf settings, sedimentation breaks, and microfaunal assemblages characteristic of these basins during the Paleogene are compared. The comparative analysis primarily concerned events of the Paleocene-Eocene thermal maximum (PETM) and beds with Azolla (aquatic fern). The formation of the Eocene Azolla Beds in the Arctic region and West Siberia was asynchronous, although it proceeded in line with a common scenario related to the development of a system of estuarine-type currents in a sea basin partly isolated from the World Ocean.

  12. Surface ultraviolet radiation over east Siberia: seasonal variations

    Directory of Open Access Journals (Sweden)

    A. V. Mikhalev

    Full Text Available The results of spectral measurements of the daily near-noon surface direct solar ultraviolet radiation in the wavelength range of 295–345 nm obtained in Irkutsk (East Siberia for the time interval of 1998–2000 are presented. For the period under consideration, the seasonal UV radiation variations are analysed that are associated with the total ozone dynamics, the transition of cyclonic and anticyclonic (Siberian anticyclone periods, the presence of snow cover, and other factors. The analysis reveals an asymmetric behaviour of the seasonal course in ground-level UV radiation around the time of the summer solstice, with seasonal variation dependence on the wavelength. We have determined the irregular variations of surface UV radiation that is typical for the region, with their properties dependent on the season and on the spectral range analysed. The similarity of the above noted features from year to year was revealed.

    Key words. Atmospheric composition and structure (Transmission and scattering of radiation; instruments and techniques – Meteorology and atmospheric dynamics (middle atmosphere dynamics

  13. Methane from the East Siberian Arctic shelf

    DEFF Research Database (Denmark)

    Petrenko...[], Vasilii V.; Etheridge, David M.

    2010-01-01

    In their Report “Extensive methane venting to the atmosphere from sediments of the East Siberian Arctic Shelf” (5 March, p. 1246), N. Shakhova et al. write that methane (CH4) release resulting from thawing Arctic permafrost “is a likely positive feedback to climate warming.” They add that the rel......In their Report “Extensive methane venting to the atmosphere from sediments of the East Siberian Arctic Shelf” (5 March, p. 1246), N. Shakhova et al. write that methane (CH4) release resulting from thawing Arctic permafrost “is a likely positive feedback to climate warming.” They add...... we conducted, suggests that a very large (~50%) increase in atmospheric CH4 concentration associated with an abrupt warming event ~11,600 years ago was driven mainly by wetlands, without distinguishing between high and low latitudes. Their reference 9 (3) was published in 1993 and is not relevant...

  14. Deciduous shrub growth and the greening of the Arctic in West Siberia

    Science.gov (United States)

    Forbes, B. C.; Macias Fauria, M.; Zetterberg, P.; Kumpula, T.

    2010-12-01

    Salix lanata and Alnus fruticosa are common and widespread shrub species in the low arctic tundra zone of West Siberia. They often occur in similar local habitats with the live portions of genets up to 100 years old. We have recently established that growth rings of S. lanata provide an excellent proxy for summer temperature. In that study our data were derived from shrubs growing on organic soils near the arctic coast of the Nenets Autonomous Okrug (NAO), west of the Ural Mountains. East of the Urals, in the Yamal-Nenets Autonomous Okrug (YNAO), climate is more continental and sandy soils provide a relatively nutrient-poor substrate for plant growth. By sampling two different species side by side on the Yamal Peninsula, we shed light on the relationship between deciduous shrubs and growing season temperatures in the last half century or so, a period of pronounced regional warming. We discern differences in the climate signal within a single species (S. lanata) as well as between it and a neighboring species with a strongly overlapping ecological amplitude (A. fruticosa). July is the main month for temperature correlation in Alnus, whereas Salix responds to June-July-August temperatures in both regions. The high correlations of shrub growth with summer temperature (r > 0.7 over the period 1956-2004) strongly suggest a link between increased shrub growth and recent decadal warming in both regions (~2°C). Both species showed significant correlation with the regional Normalized Difference Vegetation Index (NDVI), although it was somewhat lower in YNAO compared to NAO, probably due to the relative land cover (10% vs. 20%, respectively) of erect shrubs in both areas, which affects their overall contribution to the NDVI. In both regions Salix lanata biomass peaks in the second half of July. Hand-held leaf area index data from Yamal indicate a significant difference between loamy/clayey and sandy sites. We hypothesized that this same variation would be evident at the

  15. Arctic ice core records of vanillic acid from Siberia, Greenland, and Svalbard

    Science.gov (United States)

    Grieman, M. M.; Saltzman, E. S.; McConnell, J.; Fritzsche, D.; Opel, T.; Isaksson, E. D.; Schwikowski, M.

    2015-12-01

    Biomass burning is a major source for atmospheric gases and aerosols, and an important part of the global carbon cycle and radiation budget. The factors controlling centennial and millennial variability in regional to global biomass burning dynamics are not well understood because there are few well-dated proxy records only. We are exploring ice core records of organic compounds resulting from incomplete combustion of lignin as tracers for biomass burning. In this study we investigate the distribution of vanillic acid (VA) in Arctic ice cores. VA is a major product of conifer combustion, but may also be produced from angiosperms. VA was measured in ice core samples using ion chromatography with electrospray MS/MS detection. Here we present measurements of vanillic acid in three Arctic ice cores from Siberia (Akademii Nauk; 0-3 kyr bp), northern Greenland (Tunu; 0-1.75 kyr bp), and Svalbard (Lomonosovfonna; 0-0.75 kyr bp). The Siberian record exhibits 3 strong centennial scale maxima (1200-600 BC, AD 300-800, and AD 1450-1700). All three cores exhibit a smaller feature around 1250, with a subsequent decline in Greenland and Svalbard. VA levels in Greenland and Svalbard are generally smaller than those in Siberia. These results suggest strong regional input from Northern Eurasian sources (i.e. boreal forests) to the Siberian core, and lower Arctic-wide "background" levels at the other sites.

  16. Toward the problem of oil and gas bearing capacity of the East Tom-Kolyvan structural zone (Western Siberia)

    International Nuclear Information System (INIS)

    The vast depression in the east Tom-Kolyvan folded zone (West Siberia) has been identified by the geophysical data. The well which uncovered 4000 m deep profile of the Jurassic and Paleozoic deposits has been drilled. The relevance of the research is the oil/gas-bearing capacity evaluation of the discovered depression in this West Siberia area

  17. Lithologo-facial, geochemical and sequence-stratigraphic sedimentation in Naunak suite (south-east Western Siberia)

    International Nuclear Information System (INIS)

    The paper describes lithofacial, geochemical, sequence-stratigraphical research results of facial environment reconstruction and oil and evaluation gas – bearing capacity potential for Naunak suite in south-east Western Siberia

  18. Methane turnover and methanotrophic communities in arctic aquatic ecosystems of the Lena Delta, Northeast Siberia.

    Science.gov (United States)

    Osudar, Roman; Liebner, Susanne; Alawi, Mashal; Yang, Sizhong; Bussmann, Ingeborg; Wagner, Dirk

    2016-08-01

    Large amounts of organic carbon are stored in Arctic permafrost environments, and microbial activity can potentially mineralize this carbon into methane, a potent greenhouse gas. In this study, we assessed the methane budget, the bacterial methane oxidation (MOX) and the underlying environmental controls of arctic lake systems, which represent substantial sources of methane. Five lake systems located on Samoylov Island (Lena Delta, Siberia) and the connected river sites were analyzed using radiotracers to estimate the MOX rates, and molecular biology methods to characterize the abundance and the community composition of methane-oxidizing bacteria (MOB). In contrast to the river, the lake systems had high variation in the methane concentrations, the abundance and composition of the MOB communities, and consequently, the MOX rates. The highest methane concentrations and the highest MOX rates were detected in the lake outlets and in a lake complex in a flood plain area. Though, in all aquatic systems, we detected both, Type I and II MOB, in lake systems, we observed a higher diversity including MOB, typical of the soil environments. The inoculation of soil MOB into the aquatic systems, resulting from permafrost thawing, might be an additional factor controlling the MOB community composition and potentially methanotrophic capacity. PMID:27230921

  19. Coastal dynamics and submarine permafrost in shallow water of the central Laptev Sea, East Siberia

    Science.gov (United States)

    Overduin, Pier Paul; Wetterich, Sebastian; Günther, Frank; Grigoriev, Mikhail N.; Grosse, Guido; Schirrmeister, Lutz; Hubberten, Hans-Wolfgang; Makarov, Aleksandr

    2016-07-01

    Coastal erosion and flooding transform terrestrial landscapes into marine environments. In the Arctic, these processes inundate terrestrial permafrost with seawater and create submarine permafrost. Permafrost begins to warm under marine conditions, which can destabilize the sea floor and may release greenhouse gases. We report on the transition of terrestrial to submarine permafrost at a site where the timing of inundation can be inferred from the rate of coastline retreat. On Muostakh Island in the central Laptev Sea, East Siberia, changes in annual coastline position have been measured for decades and vary highly spatially. We hypothesize that these rates are inversely related to the inclination of the upper surface of submarine ice-bonded permafrost (IBP) based on the consequent duration of inundation with increasing distance from the shoreline. We compared rapidly eroding and stable coastal sections of Muostakh Island and find permafrost-table inclinations, determined using direct current resistivity, of 1 and 5 %, respectively. Determinations of submarine IBP depth from a drilling transect in the early 1980s were compared to resistivity profiles from 2011. Based on borehole observations, the thickness of unfrozen sediment overlying the IBP increased from 0 to 14 m below sea level with increasing distance from the shoreline. The geoelectrical profiles showed thickening of the unfrozen sediment overlying ice-bonded permafrost over the 28 years since drilling took place. We use geoelectrical estimates of IBP depth to estimate permafrost degradation rates since inundation. Degradation rates decreased from over 0.4 m a-1 following inundation to around 0.1 m a-1 at the latest after 60 to 110 years and remained constant at this level as the duration of inundation increased to 250 years. We suggest that long-term rates are lower than these values, as the depth to the IBP increases and thermal and porewater solute concentration gradients over depth decrease. For the

  20. Southern East Siberia PlioceneeQuaternary faults:Database, analysis and inference

    Institute of Scientific and Technical Information of China (English)

    Oksana V. Lunina; Riccardo Caputo; Anton A. Gladkov; Andrey S. Gladkov

    2014-01-01

    This paper presents the first release of an Informational System (IS) devoted to the systematic collection of all available data relating to PlioceneeQuaternary faults in southern East Siberia, their critical analysis and their seismotectonic parameterization. The final goal of this project is to form a new base for improving the assessment of seismic hazard and other natural processes associated with crustal defor-mation. The presented IS has been exploited to create a relational database of active and conditionally active faults in southern East Siberia (between 100º-114º E and 50º-57ºN) whose central sector is characterized by the highly seismic Baikal rift zone. The information within the database for each fault segment is organized as distinct but intercorrelated sections (tables, texts and pictures, etc.) and can be easily visualized as HTML pages in offline browsing. The preliminary version of the database distributed free on disk already highlights the general fault pattern showing that the Holocene and historical activity is quite uniform and dominated by NEeSW and nearly EeW trending faults;the former with a prevailing dip-slip normal kinematics, while the latter structures are left-lateral strike-slip and oblique-slip (with different proportion of left-lateral and normal fault slip components). These faults are mainly concen-trated along the borders of the rift basins and are the main sources of moderate-to-strong (M≧5.5) earthquakes on the southern sectors of East Siberia in recent times. As a whole, based on analyzing the diverse fault kinematics and their variable spatial distribution with respect to the overall pattern of the tectonic structures formed and/or activated during the late PlioceneeQuaternary, we conclude they were generated under a regional stress field mainly characterized by a relatively uniform NWeSE tension, but strongly influenced by the irregular hard boundary of the old Siberian craton. The obtained inferences are in an

  1. Morphology and biology of Cyclops scutifer Sars, 1863 in high mountain lakes of East Siberia (including Lake Amut)

    Science.gov (United States)

    Sheveleva, Natalya G.; Itigilova, Mydygma Ts.; Chananbaator, Ayushcuren

    2016-04-01

    Data on zooplankton from 13 high-mountain lakes of East Siberia have shown that the Holarctic copepod Cyclops scutifer Sars, 1863 dominates among crustaceans. In July, its abundance comprised 64%-98% of the total plankton fauna in the pelagial of these lakes, approximately 30% in the littoral zone and 10% in small northern thermokarst lakes. Biometric measurements and morphological descriptions based on scanning microscope images are supplemented by the data on its geographic distribution and phenology.

  2. Trends in the normalized difference vegetation index (NDVI) associated with urban development in arctic and subarctic Western Siberia

    Science.gov (United States)

    Outten, S.; Miles, V.; Ezau, I.

    2015-12-01

    Changes in normalized difference vegetation index (NDVI) in the high Arctic have been reliably documented, with widespread "greening" (increase in NDVI), specifically along the northern rim of Eurasia and Alaska. Whereas in West Siberia south of 65N, widespread "browning" (decrease in NDVI) has been noted, although the causes remain largely unclear. In this study we report results of statistical analysis of the spatial and temporal changes in NDVI around 28 major urban areas in the arctic and subarctic Western Siberia. Exploration and exploitation of oil and gas reserves has led to rapid industrialization and urban development in the region. This development has significant impact on the environment and particularly in the vegetation cover in and around the urbanized areas. The analysis is based on 15 years (2000-2014) of high-resolution (250 m) Moderate Resolution Imaging Spectroradiometer (MODIS) data acquired for summer months (June through August) over the entire arctic and subarctic Western Siberian region. The analysis shows that the NDVI background trends are generally in agreement with the trends reported in previous coarse-resolution NDVI studies. Our study reveals greening over the arctic (tundra and tundra-forest) part of the region. Simultaneously, the southern (boreal taiga forest) part is browning, with the more densely vegetation areas or areas with highest NDVI, particularly along Ob River showing strong negative trend. The unexpected and interesting finding of the study is statistically robust indication of the accelerated increase of NDVI ("greening") in the older urban areas. Many Siberian cities become greener even against the decrease in the NDVI background. Moreover, interannual variations of urban NDVI are not coherent with the NDVI background variability. We also find that in tundra zones, NDVI values are higher in a 5-10 km buffer zone around the city edge than in rural areas (40 km distance from the city edge), and in taiga in a 5-10 km

  3. Metabolic rate and thermal conductance of lemmings from high-arctic Canada and Siberia

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Agrell, J.; Lindström, A.

    2002-01-01

    The arctic climate places high demands on the energy metabolism of its inhabitants. We measured resting (RMR) and basal metabolic rates (BMR), body temperatures, and dry and wet thermal conductances in summer morphs of the lemmings Dicrostonyx groenlandicus and Lemmus trimucronatus in arctic Canada,

  4. Greening of the Arctic: Partitioning Warming Versus Reindeer Herbivory for Willow Populations on Yamal Peninsula, Northwest Siberia

    Science.gov (United States)

    Forbes, B. C.; Macias-Fauria, M.; Zetterberg, P.; Kumpula, T.

    2012-12-01

    Arctic warming has been linked to observed increases in tundra shrub cover and growth in recent decades on the basis of significant relationships between deciduous shrub growth/biomass and temperature. These vegetation trends have been linked to Arctic sea-ice decline and thus to the sea-ice/albedo feedback known as Arctic amplification. However, the interactions between climate, sea ice, tundra vegetation and herbivores remain poorly understood. Recently we revealed a 50-year growth response over a >100,000 km2 area to a rise in summer temperature for willow (Salix lanata), one the most abundant shrub genera at and north of the continental treeline and an important source of reindeer forage in spring, summer and autumn. We demonstrated that whereas plant productivity is related to sea ice in late spring, the growing season peak responds to persistent synoptic-scale air masses over West Siberia associated with Fennoscandian weather systems through the Rossby wave train. Substrate was important for biomass accumulation, yet a strong correlation between growth and temperature encompasses all observed soil types. Vegetation was especially responsive to temperature in early summer. However, the role of herbivory was not addressed. The present data set explores the relationship between long-term herbivory and growth trends of shrubs experiencing warming in recent decades. Semi-domestic reindeer managed by indigenous Nenets nomads occur at high densities in summer on exposed ridge tops and graze heavily on prostrate and low erect willows. A few meters away in moderately sloped landslides tall willows remain virtually ungrazed as their canopies have grown above the browse line of ca. 180 cm. Here we detail the responses of neighboring shrub populations with and without intensive herbivory yet subject to the same decadal warming trend.

  5. An assessment of the health and environmental situation in the mining community Krasnokamensk, East Siberia, Russian Federation

    Energy Technology Data Exchange (ETDEWEB)

    Ehdwall, H.; Rising, A.; Hjalmar, A.; Lindholm, I.; Persson, Bertil; Wingren, H.

    1995-12-01

    A Swedish delegation has visited a uranium mining area, Krasnokamensk, in east Siberia to find facts concerning health and environment in the area. The impression of the delegation is that the uranium activities as such have not had any significant impact on the health and environmental situation in the area. However, there is a small village within the mining area, Octyabrskij, where indoor radon levels are increased. As the Russian authorities are aware of this matter, dwellings having radon levels above the limit will be evacuated and later demolished. 19 figs, 15 tabs.

  6. An assessment of the health and environmental situation in the mining community Krasnokamensk, East Siberia, Russian Federation

    International Nuclear Information System (INIS)

    A Swedish delegation has visited a uranium mining area, Krasnokamensk, in east Siberia to find facts concerning health and environment in the area. The impression of the delegation is that the uranium activities as such have not had any significant impact on the health and environmental situation in the area. However, there is a small village within the mining area, Octyabrskij, where indoor radon levels are increased. As the Russian authorities are aware of this matter, dwellings having radon levels above the limit will be evacuated and later demolished. 19 figs, 15 tabs

  7. Adaptation, spatial variability, and phylogenetic characterization of methanotrophic communities in permafrost soils of the Lena Delta, Siberia

    OpenAIRE

    Liebner, Susanne

    2008-01-01

    The Lena Delta, located in north-east Siberia in the zone of continuous permafrost, is the largest delta within the circum-arctic. The natural capacity of arctic wetlands underlain by permafrost to emit methane is currently of major concern in the context of global change, because arctic permafrost is particularly susceptible to degradation. Permafrost degradation is suggested to impose huge amounts of yet stored carbon to the atmosphere and with this to cause a positive feedback on the natur...

  8. The exchange of carbon dioxide between wet arctic tundra and the atmosphere at the Lena River Delta, Northern Siberia

    Directory of Open Access Journals (Sweden)

    L. Kutzbach

    2007-06-01

    Full Text Available The exchange fluxes of carbon dioxide between wet arctic polygonal tundra and the atmosphere were investigated by the micrometeorological eddy covariance method. The investigation site was situated in the centre of the Lena River Delta in Northern Siberia (72°22' N, 126°30' E. The study region is characterized by a polar and distinctly continental climate, very cold and ice-rich permafrost and its position at the interface between the Eurasian continent and the Arctic Ocean. The soils at the site are characterized by high organic matter content, low nutrient availability and pronounced water logging. The vegetation is dominated by sedges and mosses. The micrometeorological campaigns were performed during the periods July–October 2003 and May–July 2004 which included the period of snow and soil thaw as well as the beginning of soil refreeze. The main CO2 exchange processes, the gross photosynthesis and the ecosystem respiration, were found to be of a generally low intensity. The gross photosynthesis accumulated to –432 g m−2 over the photosynthetically active period (June–September. The contribution of mosses to the gross photosynthesis was estimated to be about 40%. The diurnal trend of the gross photosynthesis was mainly controlled by the incoming photosynthetically active radiation. During midday the photosynthetic apparatus of the canopy was frequently near saturation and represented the limiting factor on gross photosynthesis. The synoptic weather conditions strongly affected the exchange fluxes of CO2 by changes in cloudiness, precipitation and pronounced changes of air temperature. The ecosystem respiration accumulated to +327 g m−2 over the photosynthetically active period, which corresponds to 76% of the CO2 uptake by photosynthesis. However, the ecosystem respiration continued at substantial rates during autumn when photosynthesis had ceased and the soils

  9. A closer investigation of associations between Autumn Arctic sea ice and central and east Eurasian winter climate

    Science.gov (United States)

    Wang, Shaoyin; Liu, Jiping

    2016-04-01

    Whether recent Arctic sea ice loss is responsible for recent severe winters over mid-latitude continents has emerged as a major debate among climate scientists owing to short records of observations and large internal variability in mid- and high-latitudes. In this study, we divide the evolution of autumn Arctic sea ice extent during 1979-2014 into three epochs, 1979-1986 (high), 1987-2006 (moderate) and 2007-2014 (low), using a regime shift identification method. We then compare the associations between autumn Arctic sea ice and winter climate anomalies over central and eastern Eurasia for the three epochs with focus not only on the mean state, but also the extreme events. The results show robust and detectable signals of sea ice loss in weather and climate over western Siberia and East Asia. For the mean state, anomalous low sea ice extent is associated with a strengthening of the Siberian high pressure, a weakening of westerly winds over north Asia, leading to cold anomalies in central Asia and northern China. For the extreme events, the latitude (speed) of the jet stream shifts southward (reduces), the wave extent amplifies, blocking high events increase over Ural Mountains, leading to increased frequency of cold air outbreaks extending from central Asia to northeast China. These associations bear a high degree of similarity to the observed atmospheric anomalies during the low sea ice epoch. By contrast, the patterns of atmospheric anomalies for the high sea ice epoch are different from those congruent with sea ice variability, which is related to the persistent negative phase of the Arctic Oscillation. We also found that the ENSO plays a minor role in the determination of the observed atmospheric anomalies for the three epochs. Support for these observational analysis is largely corroborated by independent atmospheric model simulations.

  10. Ancient DNA reveals prehistoric gene-flow from siberia in the complex human population history of North East Europe.

    Science.gov (United States)

    Der Sarkissian, Clio; Balanovsky, Oleg; Brandt, Guido; Khartanovich, Valery; Buzhilova, Alexandra; Koshel, Sergey; Zaporozhchenko, Valery; Gronenborn, Detlef; Moiseyev, Vyacheslav; Kolpakov, Eugen; Shumkin, Vladimir; Alt, Kurt W; Balanovska, Elena; Cooper, Alan; Haak, Wolfgang

    2013-01-01

    North East Europe harbors a high diversity of cultures and languages, suggesting a complex genetic history. Archaeological, anthropological, and genetic research has revealed a series of influences from Western and Eastern Eurasia in the past. While genetic data from modern-day populations is commonly used to make inferences about their origins and past migrations, ancient DNA provides a powerful test of such hypotheses by giving a snapshot of the past genetic diversity. In order to better understand the dynamics that have shaped the gene pool of North East Europeans, we generated and analyzed 34 mitochondrial genotypes from the skeletal remains of three archaeological sites in northwest Russia. These sites were dated to the Mesolithic and the Early Metal Age (7,500 and 3,500 uncalibrated years Before Present). We applied a suite of population genetic analyses (principal component analysis, genetic distance mapping, haplotype sharing analyses) and compared past demographic models through coalescent simulations using Bayesian Serial SimCoal and Approximate Bayesian Computation. Comparisons of genetic data from ancient and modern-day populations revealed significant changes in the mitochondrial makeup of North East Europeans through time. Mesolithic foragers showed high frequencies and diversity of haplogroups U (U2e, U4, U5a), a pattern observed previously in European hunter-gatherers from Iberia to Scandinavia. In contrast, the presence of mitochondrial DNA haplogroups C, D, and Z in Early Metal Age individuals suggested discontinuity with Mesolithic hunter-gatherers and genetic influx from central/eastern Siberia. We identified remarkable genetic dissimilarities between prehistoric and modern-day North East Europeans/Saami, which suggests an important role of post-Mesolithic migrations from Western Europe and subsequent population replacement/extinctions. This work demonstrates how ancient DNA can improve our understanding of human population movements across

  11. Ancient DNA reveals prehistoric gene-flow from siberia in the complex human population history of North East Europe.

    Directory of Open Access Journals (Sweden)

    Clio Der Sarkissian

    Full Text Available North East Europe harbors a high diversity of cultures and languages, suggesting a complex genetic history. Archaeological, anthropological, and genetic research has revealed a series of influences from Western and Eastern Eurasia in the past. While genetic data from modern-day populations is commonly used to make inferences about their origins and past migrations, ancient DNA provides a powerful test of such hypotheses by giving a snapshot of the past genetic diversity. In order to better understand the dynamics that have shaped the gene pool of North East Europeans, we generated and analyzed 34 mitochondrial genotypes from the skeletal remains of three archaeological sites in northwest Russia. These sites were dated to the Mesolithic and the Early Metal Age (7,500 and 3,500 uncalibrated years Before Present. We applied a suite of population genetic analyses (principal component analysis, genetic distance mapping, haplotype sharing analyses and compared past demographic models through coalescent simulations using Bayesian Serial SimCoal and Approximate Bayesian Computation. Comparisons of genetic data from ancient and modern-day populations revealed significant changes in the mitochondrial makeup of North East Europeans through time. Mesolithic foragers showed high frequencies and diversity of haplogroups U (U2e, U4, U5a, a pattern observed previously in European hunter-gatherers from Iberia to Scandinavia. In contrast, the presence of mitochondrial DNA haplogroups C, D, and Z in Early Metal Age individuals suggested discontinuity with Mesolithic hunter-gatherers and genetic influx from central/eastern Siberia. We identified remarkable genetic dissimilarities between prehistoric and modern-day North East Europeans/Saami, which suggests an important role of post-Mesolithic migrations from Western Europe and subsequent population replacement/extinctions. This work demonstrates how ancient DNA can improve our understanding of human population

  12. Distribution of late Pleistocene ice-rich syngenetic permafrost of the Yedoma Suite in east and central Siberia, Russia

    Science.gov (United States)

    Grosse, Guido; Robinson, Joel E.; Bryant, Robin; Taylor, Maxwell D.; Harper, William; DeMasi, Amy; Kyker-Snowman, Emily; Veremeeva, Alexandra; Schirrmeister, Lutz; Harden, Jennifer

    2013-01-01

    This digital database is the product of collaboration between the U.S. Geological Survey, the Geophysical Institute at the University of Alaska, Fairbanks; the Los Altos Hills Foothill College GeoSpatial Technology Certificate Program; the Alfred Wegener Institute for Polar and Marine Research, Potsdam, Germany; and the Institute of Physical Chemical and Biological Problems in Soil Science of the Russian Academy of Sciences. The primary goal for creating this digital database is to enhance current estimates of soil organic carbon stored in deep permafrost, in particular the late Pleistocene syngenetic ice-rich permafrost deposits of the Yedoma Suite. Previous studies estimated that Yedoma deposits cover about 1 million square kilometers of a large region in central and eastern Siberia, but these estimates generally are based on maps with scales smaller than 1:10,000,000. Taking into account this large area, it was estimated that Yedoma may store as much as 500 petagrams of soil organic carbon, a large part of which is vulnerable to thaw and mobilization from thermokarst and erosion. To refine assessments of the spatial distribution of Yedoma deposits, we digitized 11 Russian Quaternary geologic maps. Our study focused on extracting geologic units interpreted by us as late Pleistocene ice-rich syngenetic Yedoma deposits based on lithology, ground ice conditions, stratigraphy, and geomorphological and spatial association. These Yedoma units then were merged into a single data layer across map tiles. The spatial database provides a useful update of the spatial distribution of this deposit for an approximately 2.32 million square kilometers land area in Siberia that will (1) serve as a core database for future refinements of Yedoma distribution in additional regions, and (2) provide a starting point to revise the size of deep but thaw-vulnerable permafrost carbon pools in the Arctic based on surface geology and the distribution of cryolithofacies types at high spatial

  13. The exchange of energy, water and carbon dioxide between wet arctic tundra and the atmosphere at the Lena River Delta, Northern Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Kutzbach, L.

    2006-07-01

    The ecosystem-scale exchange fluxes of energy, water and carbon dioxide between wet arctic tundra and the atmosphere were investigated by the micrometeorological eddy covariance method. The investigation site was the centre of the Lena River Delta in Northern Siberia characterised by a polar and distinctly continental climate, very cold and ice-rich permafrost and its position at the interface between the Eurasian continent and the Arctic Ocean. The measurements were performed on the surface of a Holocene river terrace characterised by wet polygonal tundra. The soils at the site are characterised by high organic matter content, low nutrient availability and pronounced water logging. The vegetation is dominated by sedges and mosses. The fluctuations of the H{sub 2}O and CO{sub 2} concentrations were measured with a closed-path infrared gas analyser. The fast-response eddy covariance measurements were supplemented by a set of slow-response meteorological and soil-meteorological measurements. The combined datasets of the two campaigns 2003 and 2004 were used to characterise the seasonal course of the energy, water and CO{sub 2} fluxes and the underlying processes for the synthetic measurement period May 28..October 21 2004/2003 including the period of snow and soil thawing as well as the beginning of refreezing. The synthetic measurement period 2004/2003 was characterised by a long snow ablation period and a late start of the growing season. On the other hand, the growing season ended also late due to high temperatures and snow-free conditions in September. The cumulative summer energy partitioning was characterised by low net radiation, large ground heat flux, low latent heat flux and very low sensible heat flux compared to other tundra sites. These findings point out the major importance of the very cold permafrost for the summer energy budget of the tundra in Northern Siberia. (orig./SR)

  14. Thawing of permafrost may disturb historic cattle burial grounds in East Siberia

    Directory of Open Access Journals (Sweden)

    Boris A. Revich

    2011-11-01

    Full Text Available Climate warming in the Arctic may increase the risk of zoonoses due to expansion of vector habitats, improved chances of vector survival during winter, and permafrost degradation. Monitoring of soil temperatures at Siberian cryology control stations since 1970 showed correlations between air temperatures and the depth of permafrost layer that thawed during summer season. Between 1900s and 1980s, the temperature of surface layer of permafrost increased by 2–4°C; and a further increase of 3°C is expected. Frequent outbreaks of anthrax caused death of 1.5 million deer in Russian North between 1897 and 1925. Anthrax among people or cattle has been reported in 29,000 settlements of the Russian North, including more than 200 Yakutia settlements, which are located near the burial grounds of cattle that died from anthrax. Statistically significant positive trends in annual average temperatures were established in 8 out of 17 administrative districts of Yakutia for which sufficient meteorological data were available. At present, it is not known whether further warming of the permafrost will lead to the release of viable anthrax organisms. Nevertheless, we suggest that it would be prudent to undertake careful monitoring of permafrost conditions in all areas where an anthrax outbreak had occurred in the past.

  15. Model Projections of East Asian Summer Climate under the'Free Arctic'Scenario

    Institute of Scientific and Technical Information of China (English)

    WANG Hui-Jun; ZHANG Ying

    2010-01-01

    This paper addresses the'ice-free Arctic'issue under the future global warming scenario.Four coupled climate models used in the third phase of the Coupled Model Intercomparison Project(CMIP3)were selected to project summer climate conditions over East Asia once the Arctic becomes ice-free.The models project that an ice-free Arctic summer will begin in the 2060s under the SRESA I B(according to IPCC Special Reports on Emissions Scenarios)simulations.Our results show that the East Asian summer monsoons will tend to be stronger and that the water vapor transport to central northern China will be strengthened,leading to increased summer precipitation in central northern China.The models also project an intensified Antarctic Oscillation,a condition which favors increased precipitation in South China's Yangtze River Valley.The overall precipitation in Northwest China is projected to increase under ice-free Arctic summer conditions.

  16. Memories of Siberia

    OpenAIRE

    M D Peaple; Baker, E; Fox, R; A Pagu

    2015-01-01

    The most memorable moments of internship trip to South-East Siberia are presented in these short memories of students from Department of Earth Sciences of the University of Oxford. The students from Perm, Oxford, and La Salle universities enrolled in field geology class spent 2 weeks in Khakassia and Tyva Republics studying geology of visited deposits and gathering gold and different rock samples.

  17. 读《俄国东西伯利亚与远东考古》%Book Review:Archaeology in Eastern Siberia and Far East, Russia

    Institute of Scientific and Technical Information of China (English)

    乌恩岳斯图

    2004-01-01

    There have been close cultural relations between Russia and North China since antiquity. To make comparative studies of archaeological cultures in the two regions, we should got further knowledge of archaeological researches in Russia. Therefore, as a regional introduction to Russian archaeology, the Archaeology in Eastern Siberia and Far East, Russia, is of self-evident academic significance. The book deals in detail with archaeological cultures in "these regions and makes a comparativ estudy of them with archaeological data and literal records on Northeast China, Japan and the Korean Peninsula. With a lot of original views, it has made an excellent beginning in our study of Russian archaeology.

  18. Long-Term Arctic Peatland Dynamics, Vegetation and Climate History of the Pur-Taz Region, Western Siberia

    Science.gov (United States)

    Peteet, Dorothy; Andreev, Andrei; Bardeen, William; Mistretta, Francesca

    1998-01-01

    Stratigraphic analyses of peat composition, LOI, pollen, spores, macrofossils, charcoal, and AMS ages are used to reconstruct the peatland, vegetation and climatic dynamics in the Pur-Taz region of western Siberia over 5000 years (9300 - 4500 BP). Section stratigraphy shows many changes from shallow lake sediment to different combinations of forested or open sedge, moss, and Equisetum fen and peatland environments. Macrofossil and pollen data indicate that Larix sibirica and Betula pubescens trees were first to arrive, followed by Picea obovata. The dominance of Picea macrofossils 6000-5000 BP in the Pur-Taz peatland along with regional Picea pollen maxima indicate warmer conditions and movement of the spruce treeline northward at this time. The decline of pollen and macrofossils from all of these tree species in uppermost peats suggests a change in the environment less favorable for their growth, perhaps cooler temperatures and/or less moisture. Of major significance is the evidence for old ages of the uppermost peats in this area of Siberia, suggesting a real lack of peat accumulation in recent millennia or recent oxidation of uppermost peat.

  19. INTERBLOCK ZONES IN THE CRUST OF THE SOUTHERN REGIONS OF EAST SIBERIA: TECTONOPHYSICAL INTERPRETATION OF GEOLOGICAL AND GEOPHYSICAL DATA

    Directory of Open Access Journals (Sweden)

    K. Zh. Seminsky

    2015-09-01

    Full Text Available The zone-block structure of the lithosphere is represented by a hierarchically organized pattern of stable blocks and mobile zones which border such blocks and contain highly dislocated geological medium (Fig. 1. Today, different specialists adhere to different concepts of blocks and zones, which are two main elements of the lithosphere structure. Differences are most significant in determinations of ‘interblock zones’ that are named as deformation / destructive / contact / mobile / fracture zones etc. due to their diversity in different conditions of deformation. One of the most effective approaches to studying the zone-block structure of the lithosphere is a combination of geological and geophysical studies of interblock zones tectonic features on various scales, which can make it possible to reveal the most common patterns of the interblock zones, general regularities of their development and relationships between the interblock zones.The main objectives of our study were (1 to identify the zone-block structure of the crust in the southern regions of East Siberia from tectonophysical analysis of geological and geophysical surveys conducted on four different scales along the 500 km long Shertoy-Krasny Chikoy transect crossing the marginal segment of the Siberian block, the Baikal rift and the Transbaikalian block (Fig. 2; (2 to clarify structural features of the central part of the Baikal rift (representing the tectonic type of interblock extension zone by applying new research methods, such as radon emanation survey, to the Shertoy-Krasny Chikoy transect and using the previously applied methods, such as magnetotelluric sounding, on a smaller scale; and (3 to study manifestation of interblock zones of various ranks in different geological and geophysical fields, to reveal common specific features of their structural patterns for the upper crust, and to establish regularities of hierarchic and spatial relationships between the interblock

  20. Estimation of the permafrost stability on the East Arctic shelf under the extreme climate warming scenario for the XXI century

    Directory of Open Access Journals (Sweden)

    V. V. Malakhova

    2016-01-01

    Full Text Available A state of permafrost in the Arctic is the key to understanding whether methane, stored in the permafrost related gas hydrate, can release into the atmosphere. The global warming can lead to destabilization of the submarine permafrost and, thus, cause the methane releasing into the water. The near-bottom water temperature plays a significant role in the current state of the submarine permafrost, because it specifies a depth of thawing of the permafrost. We have numerically simulated evolution of the submarine permafrost on the East Siberia Arctic shelf for the last glacial cycle. In order to estimate a possible state and stability of the submarine permafrost we did carry out a numerical run based on the ICMMG SB RAS the coupled ocean-ice and submarine permafrost model. For the atmosphere forcing, the GFDL CM3 coupled climate model output, simulated under the scenario RCP8.5, was used. The scenario RCP8.5 was used since it predicted the strongest warming by the end of the 21-st century. The GFDL СM3 model, predicting the most pronounced Arctic warming, was also used in order to put the tentative upper boundary on the submarine permafrost degradation in this century.The results obtained show that the offshore permafrost exists across the vast East Siberia shelf. This permafrost occurs continuously but its thickness changes. Thickness of the permafrost within the most part of the East Siberia shelf is estimated 470–590 m when the value of 60 W/m2 was used for the geothermal flux. Our results reveal a certain rising of the bottom layer temperature on the shelf and subsequent penetration of a heat flux into the sediments. However, our results show that even the extreme warming is not sufficient to destabilize the submarine permafrost on the shelf of both, the Laptev Sea and the East Siberian Sea. By the end of the 21st century, upper boundary of the permafrost deepens by value from 1 to 11 m only due to the thermal effects, and by 5–10 m in

  1. Ice Complex permafrost of MIS5 age in the Dmitry Laptev Strait coastal region (East Siberian Arctic)

    Science.gov (United States)

    Wetterich, Sebastian; Tumskoy, Vladimir; Rudaya, Natalia; Kuznetsov, Vladislav; Maksimov, Fedor; Opel, Thomas; Meyer, Hanno; Andreev, Andrei A.; Schirrmeister, Lutz

    2016-09-01

    Ice Complex deposits (locally known as the Buchchagy Ice Complex) are exposed at both coasts of the East Siberian Dmitry Laptev Strait and preserved below the Yedoma Ice Complex that formed during MIS3 and MIS2 (Marine Isotope Stage) and lateglacial-Holocene thermokarst deposits (MIS1). Radioisotope disequilibria (230Th/U) of peaty horizons date the Buchchagy Ice Complex deposition to 126 + 16/-13 kyr and 117 + 19/-14 kyr until 98 ± 5 kyr and 89 ± 5 kyr. The deposit is characterised by poorly-sorted medium-to-coarse silts with cryogenic structures of horizontal ice bands, lens-like, and lens-like reticulated segregation ice. Two peaty horizons within the Buchchagy Ice Complex and syngenetic ice wedges (2-4 m wide, up to 10 m high) are striking. The isotopic composition (δ18O, δD) of Buchchagy ice-wedge ice indicates winter conditions colder than during the MIS3 interstadial and warmer than during MIS2 stadial, and similar atmospheric winter moisture sources as during the MIS2 stadial. Buchchagy Ice Complex pollen spectra reveal tundra-steppe vegetation and harsher summer conditions than during the MIS3 interstadial and rather similar vegetation as during the MIS2 stadial. Short-term climatic variability during MIS5 is reflected in the record. Even though the regional chronostratigraphic relationship of the Buchchagy Ice Complex to the Last Interglacial remains unclear because numerical dating is widely lacking, the present study indicates permafrost (Ice Complex) formation during MIS5 sensu lato, and its preservation afterwards. Palaeoenvironmental insights into past climate and the periglacial landscape dynamics of arctic lowlands in eastern Siberia are deduced from the record.

  2. THE EVOLUTION OF INTERRELATIONS BETWEEN THE RUSSIAN STATE AND THE INDIGENOUS POPULATION OF SIBERIA, FAR EAST AND RUSSIAN AMERICA IN XVII-XIX CENTURIES

    Directory of Open Access Journals (Sweden)

    Анна Валинуровна Ахметова

    2013-10-01

    Full Text Available The work sets the priorities and methods of realization of policy of the Russian state towards the indigenous population of Siberia, Far East and Russian America, reveals the changes in economical and legal status of non-Russians, as well as describes the transformation of social structure of aborigines in the process of entrance thereof to the state authorities system.Upon the performed research the series of causes of alteration of the character of interrelations between central authorities and indigenous population were revealed. The equalization of the status of domiciled non-Russians and peasants and the replacement of yasak (tribute in furs with national tax were attributable both to furs catch decline and internal changes within the aboriginal society including the alteration of economical life basis, the acculturation with Russian colonists and the transformation of closed communities of aborigines to agricultural peasant communities.DOI: http://dx.doi.org/10.12731/2218-7405-2013-9-38

  3. Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon

    Science.gov (United States)

    Semiletov, Igor; Pipko, Irina; Gustafsson, Örjan; Anderson, Leif G.; Sergienko, Valentin; Pugach, Svetlana; Dudarev, Oleg; Charkin, Alexander; Gukov, Alexander; Bröder, Lisa; Andersson, August; Spivak, Eduard; Shakhova, Natalia

    2016-05-01

    Ocean acidification affects marine ecosystems and carbon cycling, and is considered a direct effect of anthropogenic carbon dioxide uptake from the atmosphere. Accumulation of atmospheric CO2 in ocean surface waters is predicted to make the ocean twice as acidic by the end of this century. The Arctic Ocean is particularly sensitive to ocean acidification because more CO2 can dissolve in cold water. Here we present observations of the chemical and physical characteristics of East Siberian Arctic Shelf waters from 1999, 2000-2005, 2008 and 2011, and find extreme aragonite undersaturation that reflects acidity levels in excess of those projected in this region for 2100. Dissolved inorganic carbon isotopic data and Markov chain Monte Carlo simulations of water sources using salinity and δ18O data suggest that the persistent acidification is driven by the degradation of terrestrial organic matter and discharge of Arctic river water with elevated CO2 concentrations, rather than by uptake of atmospheric CO2. We suggest that East Siberian Arctic Shelf waters may become more acidic if thawing permafrost leads to enhanced terrestrial organic carbon inputs and if freshwater additions continue to increase, which may affect their efficiency as a source of CO2.

  4. Dissolved inorganic carbon, pH, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using Alkalinity titrator, CTD and other instruments from the JAKOV SMIRNITSKIY in the Beaufort Sea, East Siberia Sea and others from 2008-08-15 to 2008-09-16 (NODC Accession 0108368)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0108368 includes chemical, discrete sample, physical and profile data collected from JAKOV SMIRNITSKIY in the Beaufort Sea, East Siberia Sea, Kara...

  5. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the AKADEMIK FYODOROV in the East Siberia Sea and Laptev (or Nordenskjold) Sea from 1994-07-05 to 1994-08-08 (NODC Accession 0113884)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113884 includes chemical, discrete sample, physical and profile data collected from AKADEMIK FYODOROV in the East Siberia Sea and Laptev (or...

  6. Interannual variations of the dominant modes of East Asian winter monsoon and possible links to Arctic sea ice

    Science.gov (United States)

    Sun, Chenghu; Yang, Song; Li, Weijing; Zhang, Ruonan; Wu, Renguang

    2016-07-01

    Two dominant modes of the winter temperature over East Asia, a northern mode and a southern mode, and their links with Arctic climate conditions are analyzed. The relationships of the two modes with Arctic sea ice are different. The northern mode is closely linked to variations in sea ice of the Arctic Barents-Laptev Sea in previous autumn and most of the Arctic in concurrent winter. The southern mode seems independent from the Arctic sea ice variations, but is associated with sea surface temperature (SST) anomalies in the equatorial central-eastern Pacific. Results suggest an effect of Arctic sea ice variation on the northern mode and an influence of tropical SST anomalies on the southern mode. Reduced sea ice over the Arctic increases 1000-500-hPa thickness over the high-latitudes of Eurasian continent, which reduces the meridional thickness gradient between the middle and high latitudes and thus weakens the extratropical upper-level zonal wind. The weakened zonal wind provides a favorable dynamic condition for the development of a high-latitude ridge around the Ural Mountain. Reduced Arctic sea ice also tends to enhance the Siberian high through both thermodynamic and dynamic processes. The above atmospheric circulation patterns provide a favorable condition for the intrusion of cold air to northern East Asia.

  7. Satellite observations of aerosol transport from East Asia to the Arctic: three case studies

    Directory of Open Access Journals (Sweden)

    M. Di Pierro

    2010-11-01

    Full Text Available Vertical profiles of aerosols obtained with the CALIOP lidar onboard CALIPSO are used in conjunction with the GEOS-Chem chemical transport model and NOAA's HYSPLIT trajectory model to document three aerosol export events from East Asia to the Arctic that occurred in the year 2007. During each of these events CALIOP sampled the pollution plumes multiple times over periods of five to seven days. Meridional transport to the Arctic was rapid, taking 3–4 days and was accompanied by net diabatic heating of ~5 °C/day and precipitation in its ascending stage. Once in the Arctic transport was nearly isentropic with slow subsidence and radiative cooling at a rate of 1–1.5 °C/day. We find close agreement between modeled and observed plume in terms of length, altitude, thickness and, within the measurement uncertainties, extinction coefficient. In one event the satellite algorithm misclassifies the aerosol layer as ice clouds as a result of the relatively high depolarization ratio (0.06, likely caused by a somewhat high dust component in the aerosol mixture. The misclassification is more severe at daytime (67% of layers are misclassified than at nighttime (32%. The two most intense export events occurred in early spring within a three-week time span and are strongly related to a persisting blocking anticyclone that was located in the NW Pacific. Using 500 hPa geopotential height anomalies of these two events along with several others in 2007–2009 we develop a meteorological index that captures 40–60% of the variance of Asian transport events to the Arctic in winter and spring.

  8. Possible influence of Arctic oscillation on precipitation along the East Asian rain belt during boreal spring

    Science.gov (United States)

    Qu, Jingxuan; Gong, Daoyi; Mao, Rui; Yang, Jing; Li, Sang

    2016-08-01

    In this study, the possible influence of the springtime Arctic oscillation (AO) on precipitation along the East Asian rain belt has been studied for the period of 1979 to 2014. To capture the features of the large-scale variability of the atmospheric circulation and precipitation, singular value decomposition (SVD) analysis was performed. The domain for precipitation is from 21.25 to 33.75° N and 111.25 to 133.25° E, and the 1000 hPa heights are from 20° N northward. Prior to analysis, the El Niño-Southern Oscillation (ENSO) signals were linearly fitted and subtracted from the variables of interest. The first paired modes explain 51.1 % of the total squared covariance. The spatial feature of the pressure mode is almost identical to that of the positive AO pattern, while the precipitation mode displays an overall less-than-normal anomaly along the rain belt. The AO indices are highly correlated with the time coefficients of the pressure mode at a value of 0.91, and for the time coefficients of the precipitation mode, the correlation is -0.44, both of which are significant at the 99 % level. The regional atmospheric circulation anomalies in association with the negative phase AO mode display consistent changes, including the anomalous southerly winds and vapor flux convergence in the lower troposphere over East Asia, the stronger East Asian westerly jet stream, and the enhanced ascending air motion between 20 and 30° N. There are two possible mechanisms linking the AO and East Asian circulation and precipitation, i.e., the wave-trains along the westerly jet stream from North Africa to the Middle East and East Asia and the dipole of an anti-cyclone and a cyclone over the North Pacific.

  9. Paleomagnetism of trap intrusions, East Siberia: Implications to flood basalt emplacement and the Permo-Triassic crisis of biosphere

    Science.gov (United States)

    Konstantinov, Konstantin M.; Bazhenov, Mikhail L.; Fetisova, Anna M.; Khutorskoy, Mikhail D.

    2014-05-01

    Despite decades of concentrated studies, large igneous provinces (LIPs) are still among the most enigmatic phenomena of the Earth evolution. Among the myriad questions facing researchers, the duration of eruptive magmatic activity and its distribution through time are probably the most mysterious ones. Although the accuracy of modern dating techniques offers relatively high resolution, it is impossible to discriminate whether magmatic activity was more or less uniform or concentrated in few powerful outbursts. Consequently, many "trap-related" questions, from their origin to possible impact on the biosphere, still cannot be answered. Some of the above questions can be addressed with paleomagnetic data as have been effectively done in the case of the end-Cretaceous Deccan traps. The Siberian traps are one of the largest LIPs in the Phanerozoic and are thought, by some, to be the triggering event for the end-Permian mass extinction. We conducted a paleomagnetic study of trap intrusions along two long profiles in the eastern part of the province and found that most site-mean directions are grouped several times tighter than is common for the data on thick lava series and dyke swarms; similar over-grouping is found in other parts of the Siberian trap province too. We argue that this phenomenon is the most likely related to nearly simultaneous emplacement of trap intrusions over areas of several ten to few hundred kilometers in dimension for few millenniums or even faster. Moreover, such brief events account for all, or nearly all, magmatism in each area; how such events correlate over the entire Siberian LIP, however, remains an open question. Still, our data together with paleomagnetic results on thick lava series in Siberia strongly indicate that magmatic activity consisted of a number of brief pulses. In comparison to the other LIPs, the Siberian one is underlain by the thickest succession of carbonates, evaporites and coal-bearing clastics that are capable of

  10. Diversity of cultured photosynthetic flagellates in the North East Pacific and Arctic Oceans in summer

    Science.gov (United States)

    Balzano, S.; Gourvil, P.; Siano, R.; Chanoine, M.; Marie, D.; Lessard, S.; Sarno, D.; Vaulot, D.

    2012-06-01

    During the MALINA cruise (summer 2009) an extensive effort was undertaken to isolate phytoplankton strains from the North East (NE) Pacific Ocean, the Bering Strait, and the Beaufort Sea. Strains were isolated by flow cytometry sorting (FCS) and pipetting before or after phytoplankton enrichment of seawater samples. Strains were isolated both onboard and back in the laboratory and cultured at 4 °C under light/dark conditions. Overall, we isolated and characterised by light microscopy and 18S rRNA gene sequencing 104 strains of photosynthetic flagellates which grouped into 21 genotypes (defined by 99.5% 18S rRNA gene sequence similarity) mainly affiliated to Chlorophyta and Heterokontophyta. The taxon most frequently isolated was an Arctic ecotype of the green algal genus Micromonas (Arctic Micromonas) which was almost the only phytoplankter recovered within picoplankton (≤ 2 μm) size range. Strains of Arctic Micromonas as well as three unidentified strains related to the same genus were identified in further details by sequencing the Internal Transcribed Spacer (ITS) region of the rRNA operon. The MALINA Micromonas strains share identical 18S rRNA and ITS sequences suggesting high genetic homogeneity within Arctic Micromonas. The unidentified strains form a genotype likely belonging to a new genus within the family Mamiellaceae to which Micromonas belongs. Other green algae genotypes from the genera Nephroselmis, Chlamydomonas, Pyramimonas were also isolated whereas Heterokontophyta included Pelagophyceae, Dictyochophyceae and Chrysophyceae. Dictyochophyceae included Pedinellales which could not be identified to the genus level whereas Chrysophyceae comprised Dinobryon faculiferum. Moreover, we isolated Rhodomonas sp. as well as a few Haptophyta and dinoflagellates. We identified the dinoflagellate Woloszynskia cincta by Scanning Electron Microscopy (SEM) and 28S rRNA gene sequencing. Our morphological analyses show that this species possess the diagnostic

  11. Possible connection between summer tropical cyclone frequency and spring Arctic Oscillation over East Asia

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ki-Seon [Korea Meteorological Administration, National Typhoon Center, Jeju (Korea, Republic of); Wu, Chun-Chieh [National Taiwan University, Department of Atmospheric Sciences, Taipei (China); Byun, Hi-Ryong [Pukyong National University, Department of Environmental Atmospheric Sciences, Busan (Korea, Republic of)

    2012-06-15

    This study shows that the frequency of summer tropical cyclones (TCs) in the areas of Japan, Korea, and Taiwan (JKT), which are located in the middle latitudes of East Asia, has a positive correlation with the Arctic Oscillation (AO) occurring during the preceding spring, while summer TC frequency in the Philippines (PH), located in the low latitudes, has a negative correlation with the AO of the preceding spring. During a positive AO phase, when the anomalous anticyclone forms over the mid-latitudes of East Asia, other anomalous cyclones develop not only in the high latitudes but also in the low latitudes from the preceding spring to the summer months. With this change, while southeasterlies in the JKT area derived from the mid-latitude anticyclone plays a role in steering TCs toward this area, northwesterlies strengthened in the PH area by the low-latitude cyclone plays a role in preventing TC movement toward this area. In addition, because of this pressure systems developed during this AO phase, TCs occur, move, and recurve in further northeastern part of the western North Pacific than they do during a negative AO phase. (orig.)

  12. Appendix C: Summary of Major Metallogenic Belts in Northeast Asia (the Russian Far East, Yakutia, Siberia, Transbaikalia, Northern China, Mongolia, South Korea, and Japan)

    Science.gov (United States)

    Rodionov, Sergey M.; Obolenskiy, Alexander A.; Distanov, Elimir G.; Badarch, Gombosuren; Dejidmaa, Gunchin; Hwang, Duk-Hwan; Khanchuk, Alexander I.; Ogasawara, Masatsugu; Nokleberg, Warren J.; Parfenov, Leonid M.; Prokopiev, Andrei V.; Seminskiy, Zhan V.; Smelov, Alexander P.; Yan, Hongquan; Davydov, Yuriy V.V.; Fridovskiy, Valeriy Yu.; Gamyanin, Gennandiy N.; Gerel, Ochir; Kostin, Alexei V.; Letunov, Sergey A.; Li, Xujun; Nikitin, Valeriy M.; Ratkin, Vladimir V.; Shpikerman, Vladimir I.; Sudo, Sadahisa; Sotnikov, Vitaly I.; Spiridonov, Alexander V.; Stepanov, Vitaly A.; Sun, Fengyue; Sun, Jiapeng; Sun, Weizhi; Supletsov, Valeriy M.; Timofeev, Vladimir F.; Tyan, Oleg A.; Vetluzhskikh, Valeriy G.; Wakita, Koji; Yakovlev, Yakov V.; Zorina, Lydia M.

    2010-01-01

    tectonics of Northeast Asia that have been led by the U.S. Geological Survey (USGS). These studies have produced two broad types of publications (1) a series of regional geologic, mineral-deposit, and metallogenic-belt maps, with companion descriptions of the region, and (2) a suite of metallogenic and tectonic analyses of the same region. The study area consists of eastern Russia (most of eastern Siberia and the Russian Far East), Mongolia, northern China, South Korea, Japan, and adjacent offshore areas. The major cooperative agencies are the Russian Academy of Sciences; the Academy of Sciences of the Sakha Republic (Yakutia); VNIIOkeangeologia and Ministry of Natural Resources of the Russian Federation; the Mongolian Academy of Sciences; the Mongolian University of Science and Technology; the Mongolian National University; Jilin University, Changchun, People?s Republic of China, the China Geological Survey; the Korea Institute of Geosciences and Mineral Resources; the Geological Survey of Japan/AIST; the University of Texas, Arlington, and the U.S. Geological Survey (USGS). This study builds on and extends the data and interpretations from a previous project on the Major Mineral Deposits, Metallogenesis, and Tectonics of the Russian Far East, Alaska, and the Canadian Cordillera conducted by the USGS, the Russian Academy of Sciences, the Alaska Division of Geological and Geophysical Surveys, and the Geological Survey of Canada. The major products of this project were summarized by Naumova and others (2006) and are described in appendix A.

  13. Using isotopes to understand methane formation, removal and transport in the East Siberian Arctic Shelf

    Science.gov (United States)

    Sapart, Célia Julia; Shakhova, Natalia; Semiletov, Igor; Jansen, Joachim; van der Veen, Carina; Röckmann, Thomas

    2013-04-01

    Methane is a strong greenhouse gas emitted by human activity, but also by natural processes. Large uncertainties exist on the future contribution of natural methane sources (e.g. wetlands and geological sources) to the radiative forcing of the Earth. The Arctic regions are of special concern, because they undergo above average warming causing the thawing of permafrost thus the remobilization of large amount of organic carbon as potential methane precursor. The East Siberian Arctic Shelf (ESAS) is the shallowest and broadest continental shelf on Earth and is overlaid by thawing sub-sea permafrost. In this carbon-enriched environment, in presence of microbes and under anoxic conditions, microbial methane production is enhanced in the seafloor sediment. The methane produced can be stored in the sediment as gas hydrate, oxidized by methanotrophs or diffuse through the water column to the atmosphere. Moreover, old methane (microbial or thermogenic) from the deep ocean crust can be transported to the surface and undergo similar processes. Since a few years, large methane fluxes have been identified to the atmosphere of the ESAS, but the quantitative and qualitative understanding of the methane formation/removal/transport mechanisms remains poor. Between 2008 and 2012, several winter (ice drilling) and summer (cruise) campaigns have been performed to retrieve methane samples from different depths in the sediment and in the water column of the ESAS. We performed chemical analyses as well as measurements of methane mixing ratio and isotopic composition (stable and radioactive) on those samples. Our results allow identifying and potentially quantifying different types of methane formation/removal pathways. Moreover, they show that transport throughout the sediment and the water column can significantly alter the stable isotopic signature of the methane produced in the sediment. Hence analyzing methane stable isotopes on atmospheric samples only cannot allow discriminating

  14. Interaction of Siberia and Baltica at the final stage of amalgamation of the Eurasian part of Pangea

    Science.gov (United States)

    Shatsillo, A. V.

    2015-03-01

    The probable relative positions of the Siberian and East European cratons (Siberia and Baltica paleocontinents, respectively) during the Early Permian and the pattern of their movements at the stage of consolidation in the structure of the Pangea supercontinent are reconstructed from the paleomagnetic data. The kinematics of Siberia and Baltica indicates that they belonged to different lithospheric plates during the Permian, but since then they could have moved cooperatively. The structural data for the folded zones surrounding these cratons and the kinematical constraints suggest the most probable scenario of the interaction between Siberia and Baltica during the Permian, in which the motion of Siberia relative to Baltica was a clockwise rotation around the Euler pole located in the southwest of the Severnaya Zemlya Archipelago. This interaction between the paleocontinents agrees with the meridional lengthening, i.e., the squeezing out of the structures whose relics currently compose the basement of the West Siberian Plate along the shear zones in the southern and northern directions, and it is verified by the pattern of formation of some distinctive structures in the Central Asian folded belt and Arctic Region.

  15. Interannual modulation of East African early short rains by the winter Arctic Oscillation

    Science.gov (United States)

    Gong, Dao-Yi; Guo, Dong; Mao, Rui; Yang, Jing; Gao, Yongqi; Kim, Seong-Joong

    2016-08-01

    In the present study, we analyzed the interannual linkage between the boreal winter Arctic Oscillation (AO) and East African early short rains. When the Indian Ocean Dipole and El Niño-Southern Oscillation variance are excluded by linear regression, the boreal winter AO index is significantly correlated with the October East African precipitation over the domain of 5°N-5°S and 35°-45°E for the period 1979-2014, r =+ 0.46. The upper ocean heat content likely acts as a medium that links the AO and East African precipitation. Significant subsurface warming and positive upper ocean heat content anomalies occur over the western Indian Ocean during the autumn following positive AO winters, which enriches the atmospheric moisture, intensifies convection, and enhances precipitation. Oceanic dynamics play a key role in causing this subsurface warming. Winter AO-related atmospheric circulation creates anomalous wind stress, which forces a downwelling oceanic Rossby wave between 60°-75°E and 5°-10°S, where the thermocline significantly deepens. This Rossby wave propagates westward and accompanies significant subsurface warming along the thermocline. The Rossby wave arrives at the western Indian Ocean in the late summer, significantly warming the region to the west of 55°E at a depth of 60-100 m. This warming remains significant through October. Correspondingly, the upper ocean heat content significantly increases by approximately 2-3 × 108 J m-2 in the region west of 60°E between 5° and 10°S. The role of these oceanic dynamics in linking the winter AO, and anomalous subsurface warming was tested by numerical experiments with an oceanic general circulation model. The experiments were performed with the forcing of AO-related wind stress anomalies over the Indian Ocean in the winter. The oceanic Rossby wave generated in the central Indian Ocean during boreal winter, the consequent subsurface warming, and the anomalous upper ocean heat content in October over the

  16. Source, transport and fate of soil organic matter inferred from microbial biomarker lipids on the East Siberian Arctic Shelf

    Science.gov (United States)

    Bischoff, Juliane; Sparkes, Robert B.; Doğrul Selver, Ayça; Spencer, Robert G. M.; Gustafsson, Örjan; Semiletov, Igor P.; Dudarev, Oleg V.; Wagner, Dirk; Rivkina, Elizaveta; van Dongen, Bart E.; Talbot, Helen M.

    2016-09-01

    The Siberian Arctic contains a globally significant pool of organic carbon (OC) vulnerable to enhanced warming and subsequent release by both fluvial and coastal erosion processes. However, the rate of release, its behaviour in the Arctic Ocean and vulnerability to remineralisation is poorly understood. Here we combine new measurements of microbial biohopanoids including adenosylhopane, a lipid associated with soil microbial communities, with published glycerol dialkyl glycerol tetraethers (GDGTs) and bulk δ13C measurements to improve knowledge of the fate of OC transported to the East Siberian Arctic Shelf (ESAS). The microbial hopanoid-based soil OC proxy R'soil ranges from 0.0 to 0.8 across the ESAS, with highest values nearshore and decreases offshore. Across the shelf R'soil displays a negative linear correlation with bulk δ13C measurements (r2 = -0.73, p = soil shows limited variation, whereas the BIT index shows a rapid decline moving away from the Lena River outflow channels. This reflects a balance between delivery and removal of OC from different sources. The good correlation between the hopanoid and bulk terrestrial signal suggests a broad range of hopanoid sources, both fluvial and via coastal erosion, whilst GDGTs appear to be primarily sourced via fluvial transport. Analysis of ice complex deposits (ICDs) revealed an average R'soil of 0.5 for the Lena Delta, equivalent to that of the Buor-Khaya Bay sediments, whilst ICDs from further east showed higher values (0.6-0.85). Although R'soil correlates more closely with bulk OC than the BIT, our understanding of the endmembers of this system is clearly still incomplete, with variations between the different East Siberian Arctic regions potentially reflecting differences in environmental conditions (e.g. temperature, pH), but other physiological controls on microbial bacteriohopanepolyol (BHP) production under psychrophilic conditions are as yet unknown.

  17. Eastern Siberia terrain intelligence

    Science.gov (United States)

    U.S. Geological Survey Military Geology Branch

    1942-01-01

    The following folio of terrain intelligence maps, charts and explanatory tables represent an attempt to bring together available data on natural physical conditions such as will affect military operations in Eastern Siberia. The area covered is the easternmost section of the U.S.S.R.; that is the area east of the Yenisei River. Each map and accompanying table is devoted· to a specialized set of problems; together they cover such subjects as geology, construction materials, mineral fuels, terrain, water supply, rivers and climate. The data is somewhat generalized due to the scale of treatment as well as to the scarcity of basic data. Each of the maps are rated as to reliability according to the reliability scale on the following page. Considerable of the data shown is of an interpretative nature, although precise data from literature was used wherever possible. The maps and tables were compiled  by a special group from the United States Geological Survey in cooperation with the Intelligence Branch of the Office, Chief of Engineers, War Department.

  18. River flooding as a driver of polygon dynamics: modern vegetation data and a millennial peat record from the Anabar River lowlands (Arctic Siberia

    Directory of Open Access Journals (Sweden)

    R. Zibulski

    2013-08-01

    Full Text Available The spatial and temporal variability of a low-centred polygon on the eastern floodplain area of the lower Anabar River (72.070° N, 113.921° E; northern Yakutia, Siberia has been investigated using a multi-method approach. The present-day vegetation in each square metre was analysed, revealing a community of Larix, shrubby Betula, and Salix on the polygon rim, a dominance of Carex and Andromeda polifolia in the rim-to-pond transition zone, and a predominantly monospecific Scorpidium scorpioides coverage within the pond. The total organic carbon (TOC content, TOC / TN (total nitrogen ratio, grain size, vascular plant macrofossils, moss remains, diatoms, and pollen were analysed for two vertical sections and a sediment core from a transect across the polygon. Radiocarbon dating indicates that the formation of the polygon started at least 1500 yr ago; the general positions of the pond and rim have not changed since that time. Two types of pond vegetation were identified, indicating two contrasting development stages of the polygon. The first was a well-established moss association, dominated by submerged or floating Scorpidium scorpioides and/or Drepanocladus spp. and overgrown by epiphytic diatoms such as Tabellaria flocculosa and Eunotia taxa. This stage coincides temporally with a period in which the polygon was only drained by lateral subsurface water flow, as indicated by mixed grain sizes. A different moss association occurred during times of repeated river flooding (indicated by homogeneous medium-grained sand that probably accumulated during the annual spring snowmelt, characterized by an abundance of Meesia triquetra and a dominance of benthic diatoms (e.g. Navicula vulpina, indicative of a relatively high pH and a high tolerance of disturbance. A comparison of the local polygon vegetation (inferred from moss and macrofossil spectra with the regional vegetation (inferred from pollen spectra indicated that the moss association with

  19. Frozen ponds: production and storage of methane during the Arctic winter in a lowland tundra landscape in northern Siberia, Lena River Delta

    Directory of Open Access Journals (Sweden)

    M. Langer

    2014-07-01

    Full Text Available Lakes and ponds play a key role in the carbon cycle of permafrost ecosystems, where they are considered to be hotspots of carbon dioxide CO2 and methane CH4 emission. The strength of these emissions is, however, controlled by a variety of physical and biogeochemical processes whose responses to a warming climate are complex and only poorly understood. Small waterbodies have been attracting an increasing amount of attention since recent studies demonstrated that ponds can make a significant contribution to the CO2 and CH4 emissions of tundra ecosystems. Waterbodies also have a marked effect on the thermal state of the surrounding permafrost; during the freezing period they prolong the period of time during which thawed soil material is available for microbial decomposition. This study presents net CH4 production rates during the freezing period from ponds within a typical lowland tundra landscape in northern Siberia. Rate estimations were based on CH4 concentrations measured in surface lake ice from a variety of waterbody types. Vertical profiles along ice blocks showed an exponential increase in CH4 concentration with depth. These CH4 profiles were reproduced by a 1-D mass balance model and the net CH4 production rates then inferred through inverse modeling. Results revealed marked differences in early winter net CH4 production among various ponds. Initial state ponds underlain by stable permafrost with little or no signs of degradation yielded low net production rates, of the order of 10–11 to 10–10 mol m−2 s−1 (0.01 to 0.14 mgCH4 m−2 d−1. In contrast, advanced state ponds exhibiting clear signs of thermal erosion yielded net CH4 production rates of the order of 10–7 mol m−2 s−1 (140 mgCH4 m−2 d−1. The net production rate per square meter of advanced state ponds exceeded the maximum summer CH4 emission rates per square meter which was measured for the average tundra landscape at the study site. Our results therefore

  20. River flooding as a driver of polygon dynamics: modern vegetation data and a millennial peat record from the Anabar River lowlands (Arctic Siberia

    Directory of Open Access Journals (Sweden)

    R. Zibulski

    2013-03-01

    Full Text Available The spatial and temporal variability of a low-centred polygon on the eastern floodplain area of the lower Anabar River (72.070° N, 113.921° E, northern Yakutia, Siberia has been investigated using a multi-method approach. The present-day vegetation in each square metre was analysed revealing a community of Larix shrubby Betula and Salix on the polygon rim, a dominance of Carex and Andromeda polifolia in the rim-to-pond transition zone, and a predominantly monospecific Scorpidium scorpioides coverage within the pond. The TOC content, TOC/TN ratio, grain-size, vascular plant macrofossils, moss remains, diatoms, and pollen were analysed for two vertical sections and a sediment core from a transect across the polygon. Radiocarbon dating indicates that the formation of the polygon started at least 1500 yr ago; the general positions of the pond and rim have not changed since that time. Two types of pond vegetation were identified, indicating two contrasting development stages of the polygon. The first was a well-established moss association dominated by submerged or floating Scorpidium scorpioides and/or Drepanocladus spp. and overgrown by epiphytic diatoms such as Tabellaria flocculosa and Eunotia taxa. This stage coincides temporally with a period in which the polygon was only drained by lateral subsurface water flow, as indicated by mixed grain sizes. A different moss association occurred during times of repeated river flooding (indicated by homogeneous medium-grained sand that probably accumulated during the annual spring snow melt, characterized by an abundance of Meesia triquetra and a dominance of benthic diatoms (e.g. Navicula vulpina, indicative of a relatively high pH and a high tolerance of disturbance. A comparison of the local polygon vegetation (inferred from moss and macrofossil spectra with the regional vegetation (inferred from pollen spectra indicated that the moss association with Scorpidium scorpioides became established during

  1. Top-down versus bottom-up estimates of methane fluxes over the East Siberian Arctic Shelf

    Science.gov (United States)

    Shakhova, N. E.; Semiletov, I. P.; Repina, I.; Salyuk, A.; Kosmach, D.; Chernykh, D.; Aniferov, A.

    2014-12-01

    Global methane (CH4) emissions are currently quantified from statistical data without testing the results against either distribution of the actual atmospheric CH4 concentrations observed in different part of the globe or the regional dynamics of these concentrations. Measurement methods despite been improved remarkably in the past few years, especially with the advent of new optical and satellite-derived methods, are limited in their applicability in the Arctic. Modeling methodologies are still under development and cannot help to evolve very coarse global-scale understanding of CH4 sources to resolution of regional-scale emissions. As a result, contribution of the Arctic sources in the global CH4 budget are yet to be quantified adequately. We used a decadal observational data set collected from the water column and from the atmospheric boundary layer (ABL) over the East Siberian Arctic Shelf (ESAS), which is the largest continental shelf, to determine the minimum source strength required to explain observed seasonally increased concentration of CH4 in the ABL. The results of top-down modeling performed by implementing a simple box model show a good agreement with results of bottom-up estimates made using interpretation of in-situ calibrated sonar data.

  2. Source, transport and fate of soil organic matter inferred from microbial biomarker lipids on the East Siberian Arctic Shelf

    Science.gov (United States)

    Bischoff, Juliane; Sparkes, Robert B.; Doğrul Selver, Ayça; Spencer, Robert G. M.; Gustafsson, Örjan; Semiletov, Igor P.; Dudarev, Oleg V.; Wagner, Dirk; Rivkina, Elizaveta; van Dongen, Bart E.; Talbot, Helen M.

    2016-09-01

    The Siberian Arctic contains a globally significant pool of organic carbon (OC) vulnerable to enhanced warming and subsequent release by both fluvial and coastal erosion processes. However, the rate of release, its behaviour in the Arctic Ocean and vulnerability to remineralisation is poorly understood. Here we combine new measurements of microbial biohopanoids including adenosylhopane, a lipid associated with soil microbial communities, with published glycerol dialkyl glycerol tetraethers (GDGTs) and bulk δ13C measurements to improve knowledge of the fate of OC transported to the East Siberian Arctic Shelf (ESAS). The microbial hopanoid-based soil OC proxy R'soil ranges from 0.0 to 0.8 across the ESAS, with highest values nearshore and decreases offshore. Across the shelf R'soil displays a negative linear correlation with bulk δ13C measurements (r2 = -0.73, p = < 0.001). When compared to the GDGT-based OC proxy, the branched and isoprenoid tetraether (BIT) index, a decoupled (non-linear) behaviour on the shelf was observed, particularly in the Buor-Khaya Bay, where the R'soil shows limited variation, whereas the BIT index shows a rapid decline moving away from the Lena River outflow channels. This reflects a balance between delivery and removal of OC from different sources. The good correlation between the hopanoid and bulk terrestrial signal suggests a broad range of hopanoid sources, both fluvial and via coastal erosion, whilst GDGTs appear to be primarily sourced via fluvial transport. Analysis of ice complex deposits (ICDs) revealed an average R'soil of 0.5 for the Lena Delta, equivalent to that of the Buor-Khaya Bay sediments, whilst ICDs from further east showed higher values (0.6-0.85). Although R'soil correlates more closely with bulk OC than the BIT, our understanding of the endmembers of this system is clearly still incomplete, with variations between the different East Siberian Arctic regions potentially reflecting differences in environmental

  3. Modulation of the Arctic Oscillation and the East Asian Winter Climate Relationships by the 11-year Solar Cycle

    Institute of Scientific and Technical Information of China (English)

    CHEN Wen; ZHOU Qun

    2012-01-01

    The modulation of the relationship between the Arctic Oscillation (AO) and the East Asian winter climate by the 11-year solar cycle was investigated.During winters with high solar activity (HS),robust warming appeared in northern Asia in a positive AO phase. This result corresponded to an enhanced anticyclonic flow at 850 hPa over northeastern Asia and a weakened East Asian trough (EAT) at 500 hPa.However,during winters with low solar activity (LS),both the surface warming and the intensities of the anticyclonic flow and the EAT were much less in the presence of a positive AO phase.The possible atmospheric processes for this 11-year solar-cycle modulation may be attributed to the indirect influence that solar activity induces in the structural changes of AO.During HS winters,the sea level pressure oscillation associated with the AO became stronger,with the significant influence of AO extending to East Asia.In the meantime,the AO-related zonal-mean zonal winds tended to extend more into the stratosphere during HS winters,which implies a stronger coupling to the stratosphere.These trends may have led to an enhanced AO phase difference; thus the associated East Asian climate anomalies became larger and more significant.The situation tended to reverse during LS winters.Further analyses revealed that the relationship between the winter AO and surface-climate anomalies in the following spring is also modulated by the 11-year solar cycle,with significant signals appearing only during HS phases.Solar-cycle variation should be taken into consideration when the AO is used to predict winter and spring climate anomalies over East Asia.

  4. Placer Gold Composition and Provenance Studies in the Kuznetskiy Alatau and Western Sayan, South-East Siberia: Results of Field Trip, Summer 2014

    Directory of Open Access Journals (Sweden)

    G. J.G. Paxman

    2015-03-01

    Full Text Available This article presents the results of a study of gold samples obtained by students during a practical field trip in the summer of 2014. Placer gold samples retrieved from four rivers in southeast Siberia (Khakassia and Tyva territories by panning and sluicing were described and analyzed compositionally by Scanning Electron Microscopy. There is evidence from grain flattening and morphology for significant variations in gold transport distance, both within and between sample locations. The composition and texture of gold is compared to similar studies in the Yukon, and it is inferred that most of the placer gold in the region originated from orogenic lode sources. This orogenic gold is of Devonian to Carboniferous age. There is also evidence for a contribution from igneous intrusion-related bedrock gold, which is supported by the presence of granite, granodiorite and sienite intrusions of Devonian age. There is scope for further study, since relatively few grains were analyzed here. In addition, if compositional data of the prospective primary gold deposits can be obtained, there would be potential for more precise determination of provenance.

  5. Possible Impacts of the Arctic Oscillation on the Interdecadal Variation of Summer Monsoon Rainfall in East Asia

    Institute of Scientific and Technical Information of China (English)

    JU Jianhua; L(U) Junmei; CAO Jie; REN Juzhang

    2005-01-01

    The influences of the wintertime AO (Arctic Oscillation) on the interdecadal variation of summer monsoon rainfall in East Asia were examined. An interdecadal abrupt change was found by the end of the 1970s in the variation of the AO index and the leading principal component time series of the summer rainfall in East Asia. The rainfall anomaly changed from below normal to above normal in central China, the southern part of northeastern China and the Korean peninsula around 1978. However,the opposite interdecadal variation was found in the rainfall anomaly in North China and South China.The interdecadal variation of summer rainfall is associated with the weakening of the East Asia summer monsoon circulation. It is indicated that the interdecadal variation of the AO exerts an influence on the weakening of the monsoon circulation. The recent trend in the AO toward its high-index polarity during the past two decades plays important roles in the land-sea contrast anomalies and wintertime precipitation anomaly. The mid- and high-latitude regions of the Asian continent are warming, while the low-latitude regions are cooling in winter and spring along with the AO entering its high-index polarity after the late 1970s. In the meantime, the precipitation over the Tibetan Plateau and South China is excessive, implying an increase of soil moisture. The cooling tendency of the land in the southern part of Asia will persist until summer because of the memory of soil moisture. So the warming of the Asian continent is relatively slow in summer. Moreover, the Indian Ocean and Pacific Ocean, which are located southward and eastward of the Asian land, are warming from winter to summer. This suggests that the contrast between the land and sea is decreased in summer. The interdecadal decrease of the land-sea heat contrast finally leads to the weakening of the East Asia summer monsoon circulation.

  6. The East Siberian Arctic Shelf is a significant source of atmospheric methane as referred from multi-year ship-based observations (2000-2015)

    Science.gov (United States)

    Kosmach, D.; Semiletov, I. P.; Shakhova, N. E.; Salyuk, A.

    2015-12-01

    According to NOAA/CMDL data, the highest concentration and greatest seasonal amplitudes of atmospheric methane (CH4) occur at 60-70N, outside the 30-60N band where the main sources of anthropogenic CH4 is located, indicating that the northern environment is a source of these gases. Analyses of ice core samples also suggest a strong pole-to-pole gradient existing during inter-glacial epochs back to preindustrial times, which is independent of anthropogenic activity. The global budget of CH4 established >40 years ago, when very little knowledge existed about Arctic terrestrial sources and nothing was known about Arctic marine sources, has never considered contribution of Arctic sources of CH4 adequately. Here we present results of the multiyear high-precision continuous measurements across the Barents Sea, the Kara Sea, the Laptev Sea, the East Siberian Sea, the Chukchi Sea, the Bering Sea, the Sea of Okhotsk and the Japan Sea performed during one expedition in each of two years (2011 and 2012). Results of our investigations demonstrate that concentrations of dissolved CH4 measured in the surface water in all 8 seas were supersaturated regards to the atmosphere. However, anomalously high concentrations of dissolved CH4 in the surface water (up to 5,000-12,000% of super-saturation) was found in the East Siberian Arctic Shelf, which is composed of the Laptev Sea, the East Siberian Sea and the Chukchi Sea.

  7. Underwater collection of methane on east arctic shelf low-expensive technology of gas extraction

    OpenAIRE

    Minina, Marina

    2013-01-01

    In connection with the global warming of climate in the Arctic zone (both on dry land and in the sea shelf) began the processes of decomposition of the permafrost, accompanied by isolation into the atmosphere of carbon dioxide and methane.The enormous deposits of methane hydrates on the bottom of the Laptev Sea, Eastern Siberian and Chukchi Sea, sea of Beaufort (depth not more than 50 m) began to separate methane into entire the increasing quantity.Freely separating from sea methanehydrates m...

  8. Seismicity, structure and tectonics in the Arctic region

    Institute of Scientific and Technical Information of China (English)

    Masaki Kanao; Vladimir D. Suvorov; Shigeru Toda; Seiji Tsuboi

    2015-01-01

    The“Arctic”region, where the North Pole occupies the center of the Arctic Ocean, has been affecting the environmental variation of the Earth from geological time to the present. However, the seismic activities in the area are not adequately monitored. Therefore, by conducting long term monitoring of seismic phenomenon as sustainable parameters, our understanding of both the tectonic evolution of the Earth and the dynamic interaction between the cryosphere and geosphere in surface layers of the Earth will increase. In this paper, the association of the seismicity and structure of the Arctic region, particularly focused on Eurasian continent and surrounding oceans, and its relationship with regional evolution during the Earth’s history is studied. The target areas cover representative tectonic provinces in the Eurasian Arctic, such as the wide area of Siberia, Baikal Rift Zone, Far East Russia, Arctic Ocean together with Greenland and Northern Canada. Based on discussion including characteristics of seismicity, het-erogeneous structure of the crust and upper mantle, tectonic history and recent dynamic features of the Earth’s surface in the Arctic are summarized.

  9. Possible relationship between North Korean total rainfall and Arctic Oscillation in May

    Science.gov (United States)

    Choi, Ki-Seon; Kang, Sung-Dae; Kim, Hae-Dong

    2013-05-01

    In this study, a negative correlation between the rainfall over North Korea in May and the Arctic Oscillation (AO) in the same month is analyzed. The reasons for rainfall declines in the positive AO phase are as follows: (a) the strengthening of anomalous anticyclone in the Maritime Province of Siberia, (b) the weakening of the subtropical western North Pacific high, and (c) the stabilization across all the atmospheric layers in North Korea. Anomalous anticyclone strengthened in the Maritime Province of Siberia plays a critical role in placing the North Korean region under the influence of anomalous northeasterlies. In addition, the development of the anomalous northeasterlies results in the supply of a large amount of cold and dry air into North Korea. This consequently stabilizes the atmosphere in North Korea. Moreover, the reinforcement of anomalous cold sea surface temperature in the mid-latitude region of East Asia is found to be another reason for the atmospheric stabilization.

  10. Short-cut transport path for Asian dust directly to the Arctic: a case study

    Science.gov (United States)

    Huang, Zhongwei; Huang, Jianping; Hayasaka, Tadahiro; Wang, Shanshan; Zhou, Tian; Jin, Hongchun

    2015-11-01

    Asian dust can be transported long distances from the Taklimakan or Gobi desert to North America across the Pacific Ocean, and it has been found to have a significant impact on ecosystems, climate, and human health. Although it is well known that Asian dust is transported all over the globe, there are limited observations reporting Asian dust transported to the Arctic. We report a case study of a large-scale heavy dust storm over East Asia on 19 March 2010, as shown by ground-based and space-borne multi-sensor observations, as well as NCEP/NCAR reanalysis data and HYSPLIT trajectories. Our analysis suggests that Asian dust aerosols were transported from northwest China to the Arctic within 5 days, crossing eastern China, Japan and Siberia before reaching the Arctic. The results indicate that Asian dust can be transported for long distances along a previously unreported transport path. Evidence from other dust events over the past decade (2001-2010) also supports our results, indicating that dust from 25.2% of Asian dust events has potentially been transported directly to the Arctic. The transport of Asian dust to the Arctic is due to cyclones and the enhanced East Asia Trough (EAT), which are very common synoptic systems over East Asia. This suggests that many other large dust events would have generated long-range transport of dust to the Arctic along this path in the past. Thus, Asian dust potentially affects the Arctic climate and ecosystem, making climate change in the Arctic much more complex to be fully understood.

  11. Short-cut transport path for Asian dust directly to the Arctic: a case study

    International Nuclear Information System (INIS)

    Asian dust can be transported long distances from the Taklimakan or Gobi desert to North America across the Pacific Ocean, and it has been found to have a significant impact on ecosystems, climate, and human health. Although it is well known that Asian dust is transported all over the globe, there are limited observations reporting Asian dust transported to the Arctic. We report a case study of a large-scale heavy dust storm over East Asia on 19 March 2010, as shown by ground-based and space-borne multi-sensor observations, as well as NCEP/NCAR reanalysis data and HYSPLIT trajectories. Our analysis suggests that Asian dust aerosols were transported from northwest China to the Arctic within 5 days, crossing eastern China, Japan and Siberia before reaching the Arctic. The results indicate that Asian dust can be transported for long distances along a previously unreported transport path. Evidence from other dust events over the past decade (2001–2010) also supports our results, indicating that dust from 25.2% of Asian dust events has potentially been transported directly to the Arctic. The transport of Asian dust to the Arctic is due to cyclones and the enhanced East Asia Trough (EAT), which are very common synoptic systems over East Asia. This suggests that many other large dust events would have generated long-range transport of dust to the Arctic along this path in the past. Thus, Asian dust potentially affects the Arctic climate and ecosystem, making climate change in the Arctic much more complex to be fully understood. (letter)

  12. Power Scaling and Seasonal Changes of Floe Areas in the Arctic East Siberian Sea

    Science.gov (United States)

    Geise, Gregory R.; Barton, Christopher C.; Tebbens, Sarah F.

    2016-08-01

    The cumulative number versus floe area distribution of seasonal sea floes from six satellite images of the Arctic Ocean during the summer breakup and melting is fit by two scale-invariant power law scaling regimes for floe areas ranging from 30 to 28,400,000 m2. Scaling exponents, β, for larger floe areas range from -0.6 to -1.0 with an average of -0.8. Scaling exponents, β, for smaller floe areas range from -0.3 to -0.6 with an average of -0.5. The inflection point between the two scaling regimes ranges from 283 × 102 to 4850 × 102 m2 and generally moves from larger to smaller floe areas through the summer melting season. The stability of the power scaling results is demonstrated for two of the images by dividing each in half and analyzing each half separately, with the result that the scaling exponents and the size of the inflection points are nearly the same for each half as for the whole image. We propose that the two scaling regimes and the inflection between them are established during the initial breakup of sea ice solely by the process of fracture. The distributions of floe size regimes retain their scaling exponents as the floe pack evolves from larger to smaller floe areas from the initial breakup through the summer season, due to grinding, crushing, fracture, and melting. The scaling exponents for floe area distribution are in the same range as those reported in previous studies of Arctic floes and for the single scaling exponents found for crushed and ground geologic materials including streambed gravel, lunar debris, and artificially crushed quartz. The single scaling exponent found for fault gouge falls below the range for floes possibly because the fracturing and grinding process in fault gouge takes place under high confining pressure. A probabilistic model of fragmentation is proposed that generates a single power law scaling distribution of fragment size.

  13. Forest fire plumes sampled above Siberia during YAK-AEROSIB/POLARCAT airborne campaigns: properties and sources

    Science.gov (United States)

    Paris, J.-D.; Nedelec, P.; Stohl, A.; Arshinov, M. Yu.; Belan, B. D.; Ciais, P.

    2009-04-01

    The composition of the Siberian troposphere remains highly unknown due to a lack of measurements in this area. Siberia is a key region for a quantified understanding of many land-atmosphere exchange processes. As an example, Siberian forest fire emissions are a major extratropical source of CO to the atmosphere. Fire-emitted trace gases and particles are subject to long-range transport and may contribute to pollution of nearby Arctic. However, establishing precise top-down estimates of sources strengths based on satellite or surface network measurements for species such as CO is limited by models' ability to represent sub-grid-scale dynamics associated to the wildfire (pyroconvection) and the injection height of the plume. In an experimental effort to address this issue and to increase our knowledge of the properties of the Siberian troposphere, CO, O3, CO2 and fine particles were measured onboard a research aircraft in the frame of the YAK-AEROSIB project, partially as a contribution to the Summer 2008 POLARCAT programme. Two large scale transects were established over Northern and Central Siberia between 7 and 21 July 2008. The aircraft flight pattern consisted of ramp ascents and descents so as to sample as many vertical profiles as possible. Very high CO concentrations were observed at various altitudes, essentially in Eastern Siberia near Yakutsk and Chokurdakh. The highest concentrations (up to 600ppb) were observed between 2 and 5 km (flight ceiling being at 7km) in very thin layers (few hundreds of m thick). A Lagrangian modelling analysis (FLEXPART) revealed that the aircraft sampled fire plumes from regional fire emissions, east of Yakutsk, after about 2 days of transport. The observed fire plumes are also characterized by anomalies in O3 and excess particle concentrations. These data provide new constraints on our understanding of forest fire plume transport. They also constitute a critical testbench for the models used to assess pyrogenic emissions and

  14. Tonalites and plagiogranites of the Char suture-shear zone in East Kazakhstan:Implications for the Kazakhstan-Siberia collision

    Institute of Scientific and Technical Information of China (English)

    M.L. Kuibida; I.Yu. Safonova; P.V. Yermolov; A.G. Vladimirov; N.N. Kruk; S. Yamamoto

    2016-01-01

    The paper presents first UePb zircon ages and geochemical data from Carboniferous granitoids (tonalites and plagiogranites) of the Char sutureeshear zone in East Kazakhstan, which is located in the north-western Central Asian Orogenic Belt (CAOB). The study included analysis of geological setting, major and trace elements, and rock petrogenesis. The Char tonalites and plagiogranites occur as NW-striking linear chains inside Visean serpentinite mélange. Petrographycally, the tonalites show signs of syntec-tonic deformation, and the plagiogranites are less deformed suggesting their later intrusion. The tonalites yielded a LA-ICP-MS zircon age of ca. 323 Ma, i.e. exactly at the boundary between the early and late Carboniferous. Compositionally, the tonalites and plagiogranites are characterized, respectively, by high SiO2 (67e70 and 73e74 wt.%) and Al2O3 (17e19 and 14e15 wt.%), Sr/Y>40 and low Yb ¼ 0.2e0.5 ppm. Their multi-element patterns show clear Nb-Ta negative anomalies. The low Nb/Ta ratios (7e15) and Zr (114e191 ppm) suggest a MORB-type protolith (amphibolite) with subchondritic Nb/Ta (8e17) and low Zr (1e72 ppm). The low contents of K and Rb suggest weak assimilation of the melts by island arc felsic crust. The subchondritic Nb/Ta ratios exclude their derivation by the melting of subducted/dehydrated MORB. We argue that the Char high-Al tonalites and plagiogranites formed by the melting of hydrated MORB at the base of the mafic lower crust at pressures of 10e15 kbar. The occurrences of the Char tonalites and plagiogranites inside the Visean serpentinite mélange overlapped by Serpukhovian con-glomerates, their alignment parallel to deformation zones, and their geochemical features suggest their origin by the melting of mafic lower crust in relation to the collision of the Siberian and Kazakhstan continents.

  15. East Siberian Sea, an Arctic region of very high biogeochemical activity

    Directory of Open Access Journals (Sweden)

    L. G. Anderson

    2011-06-01

    Full Text Available Shelf seas are among the most active biogeochemical marine environments and the East Siberian Sea is a prime example. This sea is supplied by seawater from both the Atlantic and Pacific Oceans and has a substantial input of river runoff. All of these waters contribute chemical constituents, dissolved and particulate, but of different signatures. Sea ice formation during the winter season and melting in the summer has a major impact on physical as well as biogeochemical conditions. The internal circulation and water mass distribution is significantly influenced by the atmospheric pressure field. The western region is dominated by input of river runoff from the Laptev Sea and an extensive input of terrestrial organic matter. The microbial decay of this organic matter produces carbon dioxide (CO2 that oversaturates all waters from the surface to bottom relative to atmospheric level, even when primary production, inferred from low surface water nutrients, has occurred. The eastern surface waters were under-saturated with respect to CO2 illustrating the dominance of marine primary production. The drawdown of dissolved inorganic carbon equals a primary production of ~0.8 ± 2 mol C m−2, which when multiplied by half the area of the East Siberian Sea, ~500 000 km2, results in an annual primary production of 0.4 (± 1 × 1012 mol C or ~4 (± 10 × 1012 gC. Microbial decay occurs through much of the water column, but dominates at the sediment interface where the majority of organic matter ends up, thus more of the decay products are recycled to the bottom water. High nutrient concentrations and fugacity of CO2 and low oxygen and pH were observed in the bottom waters. Another signature of organic matter decomposition, methane (CH4, was observed in very high but variable concentrations. This is due to its seabed sources of glacial origin or modern production from

  16. East Siberian Sea, an arctic region of very high biogeochemical activity

    Directory of Open Access Journals (Sweden)

    L. G. Anderson

    2011-02-01

    Full Text Available Shelf seas are among the most active biogeochemical marine environments and the East Siberian Sea is a prime example. This sea is supplied by seawater from both the Atlantic and Pacific Oceans and has a substantial input of river runoff. All of these waters contribute chemical constituents, dissolved and particulate, but of different signatures. Sea ice formation during the winter season and melting in the summer has a major impact on physical as well as biochemical conditions. The internal circulation and water mass distribution is significantly influenced by the atmospheric pressure field. The western region is dominated by input of river runoff from the Laptev Sea and an extensive input of terrestrial organic matter. The microbial decay of this organic matter produces carbon dioxide (CO2 over-saturating all waters from the surface to the bottom relative to atmospheric values, even if the nutrient concentrations of the surface waters showed recent primary production. The eastern surface waters were under-saturated with respect to CO2 illustrating the dominance of marine primary production. The drawdown of dissolved inorganic carbon equals a primary production of ∼1 mol C m−2, which when multiplied by half the area of the East Siberian Sea, 500 000 km2, results in an annual primary production of 0.5×1012 mol C or 6×1012 gC. Even though microbial decay occurs through much of the water column it dominates at the sediment surface where the majority of organic matter ends up, and most of the decay products are added to the bottom water. High nutrient concentrations and fugacity of CO2 and low oxygen and pH were observed in the bottom waters. Another signature of organic matter decomposition, methane (CH4, was observed in very high but variable concentrations. This is due to its seabed sources of glacial origin or modern production from ancient organic

  17. Plant co-existence patterns and High-Arctic vegetation composition in three common plant communities in north-east Greenland

    Directory of Open Access Journals (Sweden)

    Oriol Grau

    2014-09-01

    Full Text Available Arctic regions are expected to experience substantial changes in climate in the coming decades. In order to predict potential changes of Arctic vegetation, it is important to understand the distinct role of life forms of plants and of individual species in relation to plant co-existence patterns. Our aim is to investigate if three common Arctic plant patch types dominated by contrasting life forms (by the dwarf shrubs Salix arctica or Dryas octopetala×intermedia or by mosses are related (a to the co-existence of vascular plants and species richness at patch scale and (b to the floristic composition in three distinct plant communities (Salix snowbed, Dryas heath and fell-field associated with contrasting abiotic regimes. The study was conducted at Zackenberg, in north-east Greenland. Dryas patches showed a clear negative effect on small-scale plant richness and co-existence in the fell-field. Salix and moss patches showed a similar pattern in all the plant communities, although the number of individuals growing in Salix patches was lower than in moss patches. Salix and mosses in the fell-fields hosted a high number of species in spite of the much less vegetated aspect of this harsh, upper zone. The floristic composition varied between plant communities, but it did not change substantially between patch types within each community. This study provides novel background knowledge of plant co-existence patterns at patch scale and of the structure of contrasting Arctic plant communities, which will help to better assess the potential effects of varying abiotic stress regimes on Arctic vegetation.

  18. Ozone profile observations in Siberia in 2014

    Science.gov (United States)

    Dorokhov, Valery; Balugin, Nikolay; Yushkov, Vladimir; Makshtas, Alexander; Ivlev, Georgii; Shepelev, Dmitry; Nakajima, Hideaki

    2014-05-01

    The ozonesonde observations of atmospheric ozone profiles at Salekhard aerological station (66.5N, 66.7E) in Western Siberia, Russian Federation are carried out since January 1997. In 1997-2013 we used electrochemical 2Z-ECC ozonesondes for ozone profile observations in the winter-spring period to study the ozone loss in the Arctic regions. The results of ozonesonde observation at Salekhard station are in the NDACC database. In January 2014 we upgraded this ozonesounding station with the new iMet-1 radiosonde and electrochemical 2Z-V7 ozonesonde of Droplet Measurement Technologies (DMT), USA. The first results of ozonesonde profile measurements recorded in January-March 2014 at Salekhard aerological station will be presented and discussed.

  19. Flooding in Central Siberia

    Science.gov (United States)

    2002-01-01

    A mixture of snowmelt and ice jams in late May and June of this year caused the Taz River (left) and the Yenisey River (right) in central Siberia to overflow their banks. The flooding can be seen in this image taken on June 11, 2002, by the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard the Terra satellite. Normally, the rivers would resemble thin black lines in MODIS imagery. In the false-color images sage green and rusty orange is land, and water is black. Clouds are white and pink. Credit: Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  20. Current state of forest mapping with Landsat data in Siberia

    Science.gov (United States)

    Maksyutov, Shamil; Sedykh, Vladimir; Kuzmenko, Ekaterina; Farber, Sergey; Kalinicheva, Svetlana; Fedorov, Alexander; Schepaschenko, Dmitry

    2016-04-01

    We review a current state of a forest type mapping with Landsat data in Siberia. Target algorithm should be based on dynamic vegetation approach to be applicable to the analysis of the forest type distribution for Siberia, aiming at capability of mapping Siberian forest landscapes for applications such as predicting response of forest composition to climate change. We present data for several areas in West Siberian middle taiga, Central Siberia and East Siberia near Yakutsk. Analysis of the field survey, forest inventory data was made to produce forest type classification accounting for several stages for forest succession and variations in habitats and landforms. Supervised classification was applied to the areas were the ground truth and inventory data are available, including several limited area maps and vegetation survey transects. In Laryegan basin in West Siberia the upland forest areas are dominated by mix of Scots pine on sandy soils and Siberian pine with presence of fir and spruce on the others. Abundance of Scots pine decreases to the west due to change in soils. Those types are separable using Landsat spectral data. In the permafrost area around Yakutsk the most widespread succession type is birch to larch. Three stages of the birch to larch succession are detectable from Landsat image. When Landsat data is used in both West and East Siberia, distinction between deciduous broad-leaved species (birch, aspen, and willow) is generally difficult. Similar problem exist for distinguishing between dark coniferous species (Siberian pine, fir and spruce). Image classification can be improved by applying landform type analysis, such as separation into floodplain, terrace, sloping hills. Additional layers of information can be a promising way to complement Landsat data.

  1. Mid to late Holocene strengthening of the East Greenland Current paralleled by increased Atlantic Intermediate Water outflow from the Arctic Ocean

    Science.gov (United States)

    Perner, Kerstin; Moros, Matthias; Llyod, Jeremy; Jansen, Eystein; Stein, Rüdiger

    2015-04-01

    The relatively fresh and cold East Greenland Current (EGC) connects the Arctic with the subpolar North Atlantic. Its strength and influence on the freshwater balance in the North Atlantic impacts Subpolar gyre (SPG) dynamics and deep convection in the Labrador Sea. Enhanced freshwater and sea ice expansion in the subpolar North Atlantic is suggested to modify the northward heat transport in the North Atlantic Current (NAC). High-resolution palaeoceanographic reconstructions, based on planktonic and benthic foraminifera assemblage data, from the central East Greenland shelf (Foster Bugt) reveal distinct centennial to millennial-scale oceanographic variability that relate to climatic changes during the mid to late Holocene (last c. 6.3 ka BP). Our data highlight intervals of cooling and freshening of the polar surface EGC waters that accompanies warming in the underlying subsurface Atlantic waters, which receives contribution of return Atlantic Intermediate Water (AIW) and of the Return Atlantic Current (RAC). Mid Holocene thermal optimum-like conditions prevailed until c. 4.5 ka BP. A relatively warm surface PW and strong contribution of subsurface RAC waters, alongside low drift/sea ice occurrence, suggest a relatively weak EGC during this period. Subsequently, from 4.5 to 1.4 ka BP, the surface PW layer freshened and cooled, and the water column became well stratified, indicating a strong EGC. This EGC strengthening is accompanied by increasing subsurface AIW contribution from the Arctic Ocean after c. 4.5 ka BP, which culminated in the time from 2.3 to 1.4 ka BP. Simultaneously to this maximum AIW contribution, distinct warming is also recognized in the NAC, the Irminger Current and the West Greenland Current. We relate this enhanced Arctic Ocean AIW contribution to the 'Roman Warm Period'; a warm phase whose origin is still a matter of debate. We suggest that the observed warming offshore East Greenland, centred at c. 2.0 ka BP, results from the interaction of i

  2. Structural features of humic acids from a soil toposequence in Western Siberia

    OpenAIRE

    klenov, B. M.; González-Vila, Francisco Javier; Almendros Martín, Gonzalo

    2008-01-01

    Western Siberia occupies the middle part of Russia. This area extends more than 3000 km from the West to East and more than 1500 km from the North to the South and it is characterized by a diversity of natural conditions. In the Western Siberia the latitudinal and vertical zonality of soil and plant cover is more clearly pronounced. Soil-forming conditions, environmental situation and soil genesis have been studied rather completely where, to some degree, the changes of humus composition have...

  3. IN WESTERN SIBERIA

    Directory of Open Access Journals (Sweden)

    Chizhikov Il'ja Aleksandrovich

    2012-10-01

    along the oil transportation route that connected three Salym oil fields in Western Siberia.

  4. Season - dependent and source-influenced aerosol in Northern Siberia

    Science.gov (United States)

    Popovicheva, Olga; Makshtas, Alexander; Bogorodsky, Peter; Eleftheriadis, Kostantinos; Diapouli, Evangelia; Shonia, Natalia; Uttal, Taneil

    2016-04-01

    Aerosol may serve as a tracer of arctic pollution, allowing a link to climate response if its major characteristics relating to natural and anthropogeneous sources are defined. It has been shown that BC and sulfates are the most important aerosol constituents measured in the Arctic boundary layer; these species demonstrate similar seasonal variations with a peak during winter to early spring and a minimum in summer. Long - time gap in consistent aerosol observations in the Russian Arctic strongly limits the assessment of air pollution and climate impacts. On-line monitoring, sampling, and analyses of atmospheric aerosols were carried out at the Tiksi Hydrometeorological Observatory, Northern Siberia, during one year from September 2014 to 2015. Physico-chemical characterization combining aethalometry, thermo-optical analysis, and analytical chemistry was used in order to identify the seasonal variability of aerosols and to link their composition to possible sources, as well as to characterize the differences in aerosol chemical composition between natural background conditions and BC-pollution episodes. The present study reports the first results from the Tiksi Observatory on season-dependent and source-influenced characteristics of aerosol species, such as carbon fractions (OC, EC), inorganic and organic functionalities of chemical compounds, sulfates, nitrates and other ion components, and elements. In addition, data obtained by individual particles analysis provide insight into micromarkers of combustion sources. Aerosol at the Tiksi Observatory is found to be originated from natural marine, biogenic, and continental sources as well as influenced by local residential activity and regional pollution. Characterization of aerosols during OC and BC-pollution episodes, combined with analysis of the wind direction, atmosphere stability, and air mass trajectories, allows for the identification of the sources which are responsible for the emission of hazardous compounds

  5. On the connection among components of carbon cycling and water mass parameters in the East Siberian Arctic Shelf: The First Quantitative Assessment.

    Science.gov (United States)

    Semiletov, Igor; Shakhova, Natalia; Pugach, Svetlana; Pipko, Irina; Dudarev, Oleg

    2010-05-01

    The East Siberian Arctic Shelf (ESAS), the widest and shallowest ocean shelf in the world, is an important region for producing and processing organic matter before the material is transported into the Arctic Ocean. Up to 100% of the total organic carbon (TOC) in the ESAS surface sediments is terrestrial by origin (TOCterr). TOCterr flux in the ESAS integrates riverine and coastal erosion signals, transforming TOCterr to carbon dioxide and other components within the land-shelf-atmosphere system. Degradation of eroded organic carbon produces a decrease in values of pH (causing ocean acidification) and dissolved oxygen, while producing an increase in the partial pressure of carbon dioxide (pCO2), total CO2 (TCO2), and nutrients (Semiletov, 1999; Semiletov et al., 2007; Anderson et al., 2009). Ongoing warming causes thawing of the permafrost underlying a majority of arctic river watersheds and more than 80% of the ESAS area; this process could accelerate river discharge, carbon losses from soils, involvement of old carbon in the modern carbon cycle, and the mobilization of previously-originated methane (CH4) that is currently stored within seabed deposits (Shakhova and Semiletov, 2009). Given current and predicted dramatic Arctic climate changes, baseline measurements are critical to elucidating Arctic carbon cycle feedback processes, predicting climate response, and understanding the likely ecological changes in the oligotrophic ESAS under future warmer (ice-free) climate scenarios. Here we present the first quantitative assessment of the connection among the components of carbon cycling and water mass parameters in the ESAS. Our results are based on a complex biogeochemical study performed by our group during 1997-2007. A strong regional correlation (~0.96) was found between the dissolved organic carbon (DOC) concentration and colored dissolved organic matter (CDOM) fluorescence measured in situ using the WETStar fluorometer, and between the "filtered" particulate

  6. Reanalysis Data Evaluation to Study Temperature Extremes in Siberia

    Science.gov (United States)

    Shulgina, T. M.; Gordov, E. P.

    2014-12-01

    Ongoing global climate changes are strongly pronounced in Siberia by significant warming in the 2nd half of 20th century and recent extreme events such as 2010 heat wave and 2013 flood in Russia's Far East. To improve our understanding of observed climate extremes and to provide to regional decision makers the reliable scientifically based information with high special and temporal resolution on climate state, we need to operate with accurate meteorological data in our study. However, from available 231 stations across Siberia only 130 of them present the homogeneous daily temperature time series. Sparse, station network, especially in high latitudes, force us to use simulated reanalysis data. However those might differ from observations. To obtain reliable information on temperature extreme "hot spots" in Siberia we have compared daily temperatures form ERA-40, ERA Interim, JRA-25, JRA-55, NCEP/DOE, MERRA Reanalysis, HadEX2 and GHCNDEX gridded datasets with observations from RIHMI-WDC/CDIAC dataset for overlap period 1981-2000. Data agreement was estimated at station coordinates to which reanalysis data were interpolated using modified Shepard method. Comparison of averaged over 20 year annual mean temperatures shows general agreement for Siberia excepting Baikal region, where reanalyses significantly underestimate observed temperature behavior. The annual temperatures closest to observed one were obtained from ERA-40 and ERA Interim. Furthermore, t-test results show homogeneity of these datasets, which allows one to combine them for long term time series analysis. In particular, we compared the combined data with observations for percentile-based extreme indices. In Western Siberia reanalysis and gridded data accurately reproduce observed daily max/min temperatures. For East Siberia, Lake Baikal area, ERA Interim data slightly underestimates TN90p and TX90p values. Results obtained allows regional decision-makers to get required high spatial resolution (0,25°×0

  7. Russian Arctic Petroleum Resources; Ressources petrolieres de l'Arctique russe

    Energy Technology Data Exchange (ETDEWEB)

    Zolotukhin, A.; Gavrilov, V. [Gubkin Russian State University of Oil and Gas, GSP-1, Leninsky prospekt, 65, 119991, Moscow - (Russian Federation)

    2011-07-01

    The Arctic continental shelf is believed to be the area with the highest unexplored potential for oil and gas as well as for unconventional hydrocarbon resources such as gas hydrates. Despite a common view that the Arctic has plentiful of hydrocarbon resources, there are ongoing debates regarding the potential of this region as a future energy supply base. Driving forces for such discussions are geopolitics, environmental concern, assessment and delineation of Arctic resources, technology available for their successful development and the market demand for energy supply. The Russian part is recognized to be the largest among oil and gas resources owned by Arctic nations. However, scarce information and available geological data create uncertainty regarding a future role of the Russian Arctic as main base of energy supply in the second part of the 21. century. A further uncertainty is the pace at which production from northern areas including the Arctic will be brought on stream - either because of national policy, infrastructure development or investment by the state and the oil companies. These areas embrace those where development has already been started (Offshore Sakhalin, northern Timan Pechora) and those awaiting future involvement, like Barents and Pechora seas, East Siberia, Yamal, Kara Sea and Kamchatka. Offshore production levels are likely to be very important to Russia in mid and long terms, especially as most (if not all) production will go for export and, in the process, open doors to new markets. In this way, offshore production will introduce a new and very significant component to Russia's export strategy. However, active involvement of the Russian Arctic resources in the global energy supply process needs a detailed analysis and clear understanding of the market potential for Russian gas and oil (required volumes, time frame, transportations routes) and requires close attention of the government to the most important issues that should be in

  8. Stratospheric column NO2 anomalies over Russia related to the 2011 Arctic ozone hole

    Science.gov (United States)

    Aheyeva, Viktoryia; Gruzdev, Aleksandr; Elokhov, Aleksandr; Grishaev, Mikhail; Salnikova, Natalia

    2013-04-01

    We analyze data of spectrometric measurements of stratospheric column NO2 contents at mid- and high-latitude stations of Zvenigorod (55.7°N, Moscow region), Tomsk (56.5°N, West Siberia), and Zhigansk (66.8°N, East Siberia). Measurements are done in visual spectral range with zenith-viewing spectrometers during morning and evening twilights. Alongside column NO2 contents, vertical profiles of NO2 are retrieved at the Zvenigorod station. Zvenigorod and Zhigansk are the measurement stations within the Network for the Detection of Atmospheric Composition Change (NDACC). For interpretation of results of analysis of NO2 data, data of Ozone Monitoring Instrument measurements of total column ozone and rawinsonde data are also analyzed and back trajectories calculated with the help of HYSPLIT trajectory model are used. Significant negative anomalies in stratospheric NO2 columns accompanied by episodes of significant cooling of the stratosphere and decrease in total ozone were observed at the three stations in the winter-spring period of 2011. Trajectory analysis shows that the anomalies were caused by the transport of stratospheric air from the region of the ozone hole observed that season in the Arctic. Although negative NO2 anomalies due to the transport from the Arctic were also observed in some other years, the anomalies in 2011 have had record magnitudes. Analysis of NO2 vertical profiles at Zvenigorod shows that the NO2 anomaly in 2011 compared to other years anomalies was additionally contributed by the denitrification of the Arctic lower stratosphere. NO2 profiles show that a certain degree of the denitrification probably survived even after the ozone hole.

  9. A 350 ka record of climate change from Lake El'gygytgyn, Far East Russian Arctic: refining the pattern of climate modes by means of cluster analysis

    Directory of Open Access Journals (Sweden)

    U. Frank

    2013-07-01

    Full Text Available Rock magnetic, biochemical and inorganic records of the sediment cores PG1351 and Lz1024 from Lake El'gygytgyn, Chukotka peninsula, Far East Russian Arctic, were subject to a hierarchical agglomerative cluster analysis in order to refine and extend the pattern of climate modes as defined by Melles et al. (2007. Cluster analysis of the data obtained from both cores yielded similar results, differentiating clearly between the four climate modes warm, peak warm, cold and dry, and cold and moist. In addition, two transitional phases were identified, representing the early stages of a cold phase and slightly colder conditions during a warm phase. The statistical approach can thus be used to resolve gradual changes in the sedimentary units as an indicator of available oxygen in the hypolimnion in greater detail. Based upon cluster analyses on core Lz1024, the published succession of climate modes in core PG1351, covering the last 250 ka, was modified and extended back to 350 ka. Comparison to the marine oxygen isotope (δ18O stack LR04 (Lisiecki and Raymo, 2005 and the summer insolation at 67.5° N, with the extended Lake El'gygytgyn parameter records of magnetic susceptibility (κLF, total organic carbon content (TOC and the chemical index of alteration (CIA; Minyuk et al., 2007, revealed that all stages back to marine isotope stage (MIS 10 and most of the substages are clearly reflected in the pattern derived from the cluster analysis.

  10. [Horse, cow and reindeer were converted into arctic domestic animals].

    Science.gov (United States)

    Kantanen, Juha

    2016-01-01

    Domestic animal production in the arctic region is often thought to be based exclusively on reindeer herding. There are, however, regions in Northern Europe and Siberia having a long tradition in rearing breeds of cattle and horse adapted to the northers conditions also. The development of these arctic animal breeds has been largely founded on old tradition rather than on the programs of breeding organizations. As a result of the selection carried out by nature and man, the domestic animals of arctic regions express characteristics that are metabolic, structural, associated with reproductive physiology and conducive to the adaptation to arctic conditions. PMID:27522831

  11. Can antibrowsing defense regulate the spread of woody vegetation in arctic tundra?

    Science.gov (United States)

    Bryant, John P.; Joly, Kyle; Chapin, F. Stuart; DeAngelis, Donald L.; Kielland, Knut

    2014-01-01

    Global climate warming is projected to promote the increase of woody plants, especially shrubs, in arctic tundra. Many factors may affect the extent of this increase, including browsing by mammals. We hypothesize that across the Arctic the effect of browsing will vary because of regional variation in antibrowsing chemical defense. Using birch (Betula) as a case study, we propose that browsing is unlikely to retard birch expansion in the region extending eastward from the Lena River in central Siberia across Beringia and the continental tundra of central and eastern Canada where the more effectively defended resin birches predominate. Browsing is more likely to retard birch expansion in tundra west of the Lena to Fennoscandia, Iceland, Greenland and South Baffin Island where the less effectively defended non-resin birches predominate. Evidence from the literature supports this hypothesis. We further suggest that the effect of warming on the supply of plant-available nitrogen will not significantly change either this pan-Arctic pattern of variation in antibrowsing defense or the resultant effect that browsing has on birch expansion in tundra. However, within central and east Beringia warming-caused increases in plant-available nitrogen combined with wildfire could initiate amplifying feedback loops that could accelerate shrubification of tundra by the more effectively defended resin birches. This accelerated shrubification of tundra by resin birch, if extensive, could reduce the food supply of caribou causing population declines. We conclude with a brief discussion of modeling methods that show promise in projecting invasion of tundra by woody plants.

  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 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...

  13. 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...

  14. Pliocene to Pleistocene climate and environmental history of Lake El'gygytgyn, Far East Russian Arctic, based on high-resolution inorganic geochemistry data

    Directory of Open Access Journals (Sweden)

    V. Wennrich

    2013-10-01

    Full Text Available The 3.6 Ma sediment record of Lake El'gygytgyn, Far East Russian Arctic, represents the longest continuous climate archive of the terrestrial Arctic. Its elemental composition monitored by X-ray fluorescence scanning exhibits significant changes since the Mid-Pliocene caused by climate driven variations in the primary production, postsedimentary diagenetic processes, and current activity in the lake as well as weathering processes in its catchment. During the Mid to Late Pliocene, warmer and wetter climatic conditions are reflected by elevated Si / Ti ratios, indicating enhanced diatom production in the lake. Prior to 3.3 Ma, this signal is highly masked by intensified detrital input from the catchment, visible in maxima of clastic-related proxies such as the K concentration. In addition, calcite formation in the early lake history points to enhanced nutrient flux into the lake caused by intensified weathering in its catchment. Its termination at ca. 3.3 Ma is supposed to be linked to the development of permafrost in the region triggered by a first cooling in the Mid-Pliocene. After ca. 3.0 Ma the elemental data suggest a gradual transition to Quaternary-style glacial / interglacial cyclicity. In the early Pleistocene, the cyclicity was first dominated by variations on the 41 ka obliquity band but experienced a change to a 100 ka eccentricity dominance after the Middle Pleistocene Transition at ca. 1.2 to 0.7 Ma. This clearly demonstrates the sensitivity of the Lake El'gygytgyn record to orbital forcing. A successive decrease of the baseline-levels of the redox-sensitive Mn / Fe ratio and magnetic susceptibility between 2.3 to 1.8 Ma reflects an overall change in the bottom water oxygenation due to an intensified occurrence of pervasive glacial episodes in the early Quaternary. The coincidence with major changes in the North Pacific and Bering Sea paleoceanography at ca. 1.8 Ma implies that the change in lake hydrology was caused by regional

  15. A biomarker record of Lake El'gygytgyn, Far East Russian Arctic: investigating sources of organic matter and carbon cycling during marine isotope stages 1–3

    Directory of Open Access Journals (Sweden)

    A. R. Holland

    2013-01-01

    Full Text Available Arctic paleoenvironmental archives serve as sensitive recorders of past climate change. Lake El'gygytgyn (Far East Russian Arctic is a high-latitude crater impact lake that contains a continuous sediment record influenced by neither glaciation nor glacial erosion since the time of impact 3.58 Ma ago. Prior research on sediments collected from Lake El'gygytgyn suggest times of permanent ice cover and anoxia corresponding to global glacial intervals, during which the sediments are laminated and are characterized by the co-occurrence of high total organic carbon, microscopic magnetite grains that show etching and dissolution, and negative excursions in bulk sediment organic matter carbon isotope (δ13C values. Here we investigate the abundance and carbon isotopic composition of lipid biomarkers recovered from Lake El'gygytgyn sediments spanning marine isotope stages 1–3 to identify key sources of organic matter (OM to lake sediments, to establish which OM sources drive the negative δ13C excursion exhibited by bulk sediment OM, and to explore if there are molecular and isotopic signatures of anoxia in the lake during glaciation. We find that during marine isotope stages 1–3, direct evidence for water column anoxia is lacking. A ~4‰ negative excursion in bulk sediment δ13C values during the Local Last Glacial Maximum (LLGM is accompanied by more protracted, higher magnitude negative excursions in n-alkanoic acid and n-alkanol δ13C values that begin 20 kyr in advance of the LLGM. In contrast, n-alkanes and the C30 n-alkanoic acid do not exhibit a negative δ13C excursion at this time. Our results indicate that the C24, C26 and C28 n-alkanoic acids do not derive entirely from terrestrial OM sources, while the C30 n-alkanoic acid at Lake El'gygytgyn is a robust indicator of terrestrial OM contributions. Overall, our results strongly support the presence of a nutrient-poor water column, which is mostly isolated from atmospheric carbon dioxide

  16. 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

  17. The Taimyr Peninsula and the Severnaya Zemlya archipelago, Arctic Russia

    DEFF Research Database (Denmark)

    Möller, Per; Alexanderson, Helena; Funder, Svend Visby;

    2015-01-01

    We here suggest a glacial and climate history of the Taimyr Peninsula and Severnaya Zemlya archipelago in arctic Siberia for the last about 150 000 years (ka). Primarily it is based on results from seven field seasons between 1996 and 2012, to a large extent already published in papers referred t...

  18. 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.

  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. Comparison of satellite imagery and infrared aerial photography as vegetation mapping methods in an arctic study area: Jameson Land, East Greenland

    DEFF Research Database (Denmark)

    Hansen, Birger Ulf; Mosbech, Anders

    1994-01-01

    Remote Sensing, vegetation mapping, SPOT, Landsat TM, aerial photography, Jameson Land, East Greenland......Remote Sensing, vegetation mapping, SPOT, Landsat TM, aerial photography, Jameson Land, East Greenland...

  1. Do Arctic waders use adaptive wind drift?

    OpenAIRE

    Green, M.; Alerstam, T; Gudmundsson, GA; Hedenstrom, A; Piersma, T; Gudmundsson, Gudmundur A.; Hedenström, Anders

    2004-01-01

    We analysed five data sets of night directions of migrating arctic waders ill relation to,winds, recorded by tracking radar and optical range finder, in order to find out if these birds compensate for wind drift, or allow themselves to be drifted by winds. Our purpose was to investigate whether arctic waders use adaptive wind drift strategies or not. The data sets were collected in Siberia (two sets) and Canada during post-breeding (autumn) migration, and in Mauritania and South Sweden during...

  2. Satellite observations of long range transport of a large BrO cloud in the Arctic

    Directory of Open Access Journals (Sweden)

    M. Begoin

    2009-09-01

    Full Text Available Ozone Depletion Events (ODE during polar springtime are a well known phenomenon in the Arctic and Antarctic boundary layer. They are caused by the catalytic destruction of ozone by halogens producing reactive halogen oxides like bromine monoxide (BrO. The key halogen bromine can be rapidly transferred into the gas phase in an autocatalytic process – the so called "Bromine Explosion". However, the exact mechanism, which leads to an initial bromine release as well as the influence of transport and chemical processes on BrO, is still not clearly understood. In this study, BrO measurements from the satellite instrument GOME-2 are used together with model calculations with the dispersion model FLEXPART and Potential Frost Flowers (PFF maps to study a special arctic BrO event in March/April 2007, which could be tracked over many days and large areas. Full BrO activation was observed within one day east of Siberia with subsequent transport to the Hudson Bay. The event was linked to a cyclone with very high surface wind speeds which could have been involved in the production and the sustaining of aerosols providing the surface for BrO recycling within the plume. The evolution of the BrO plume could be well reproduced by FLEXPART calculations for a passive tracer indicating that the activated air mass was transported all the way from Siberia to the Hudson Bay without further activation at the surface. No direct link could be made to frost flower occurrence and BrO activation but enhanced PFF were observed a few days before the event in the source regions.

  3. Bryophytes collected during a Dutch botanical East Greenland expedition to the Angmagsslalik area in 1966

    NARCIS (Netherlands)

    Molenaar, de J.G.

    1968-01-01

    From a bryological point of view Greenland is not well known in detail. Unlike Siberia or Arctic America, it is not known through a few large collections, but through multitudes of mostly relatively small gatherings. In this arctic island that is almost 2000 miles long and extends from below 60° N.l

  4. Crustal types of the Circumpolar Arctic

    Science.gov (United States)

    Kashubin, Sergey; Pavlenkova, Ninel; Petrov, Oleg; Milshtein, Evgenia; Shokalsky, Sergey; Erinchek, Yuri

    2016-04-01

    combined with "subcontinental" crust of the Farrero-Iceland and Rockall ridges. This transition type is also revealed along the Greenland and West Europe margins. An important feature of the High Arctic is the system of faults outlining the central part of the ocean. The faults indicate clear differences in their tectonic evolution. Two of them are the long seismic active zones of global significance: they are traced along the North America continental margin and the Gakkel Ridge and may be continued far to the continents as the high seismicity belts. The faults between the central Arctic and the East Siberia-Alaska margins are divided in several passive seismicity segments. Along the most fault zones the deep basins are formed, the crustal type is changed and the Moho has step form.

  5. Assessment of Sea-Air Fluxes of Methane from the East Siberian Arctic Shelf Based on Multi-Year High-Precision Observations in the Atmospheric Boundary Layer and Seawater

    Science.gov (United States)

    Salyuk, A.; Semiletov, I. P.; Repina, I.; Chernykh, D.; Kosmach, D.; Shakhova, N. E.

    2015-12-01

    The latitude specific monthly mean (LSMM) methane (CH4) mixing ratio in the Arctic region atmospheric boundary layer (ABL) is established at 1.85 ppm (monitoring station at Barrow, Alaska, USA). This LSMM is about 10% higher than in Antarctica and about 5-7% higher than in the mid-latitudes, where the majority of anthropogenic activity occurs. So far, there is no reasonable explanation for the atmospheric CH4 maximum above the Arctic and no models have succeeded in satisfactorily reproducing the inter-polar gradient, due to the assumption that there are no Arctic region CH4 sources sufficient to serve year-round to maintain the existing maximum. The East Siberian Arctic Shelf (ESAS), from which extensive CH4 release was recently reported, has never been considered to be an atmospheric source of CH4, because no knowledge existed about this area until very recently. One focus of our multi-year ESAS investigations was to collect a comprehensive data set of continuous ABL CH4 mixing ratio measurements along with continuous measurements of dissolved CH4 in the surface water. When collecting the data set, we aimed to assess CH4 fluxes by using top-down and bottom-up approaches. Achieving representative spatial coverage of the study area with high-resolution, high-accuracy measurements was our priority. We collected data from 2006-2012 with a high-accuracy fast CH4 analyzer; two sonic anemometers measured the 3D wind vector and sonic temperature; a meteorological station measured wind speed and direction, moisture, and temperature; and an open path infrared gas analyzer measured H2O and CO2. Other instruments included a pressure transducer and a motion package that measured 6 components of ship's motion and also acceleration, magnetic field, and position. In 2011 and 2012 we performed such measurements in the outer ESAS seepage area. Data were synchronized in time and space to demonstrate correspondence of increased atmospheric CH4 levels (up to 3.2 ppm) to observed

  6. The effect of preceding wintertime Arctic polar vortex on springtime NDVI patterns in boreal Eurasia, 1982-2015

    Science.gov (United States)

    Li, Jing; Fan, Ke; Xu, Jianjun; Powell, Alfred M.; Kogan, Felix

    2016-08-01

    The polar vortex is implicated in certain cold events in boreal Eurasia and has a further influence on land surface properties (e.g., vegetation and snow) during spring. The Normalized Difference Vegetation Index (NDVI) can be used as a proxy of land surface responses to climate changes to a certain degree. In this study, we demonstrate the significant correlation between preceding wintertime Arctic polar vortex intensity (WAPVI) and springtime NDVI (SNDVI) over a 34-year period (1982-2015) in boreal Eurasia (50°-75°N, 0°-150°E). Results show that a positive phase of WAPVI tends to increase the SNDVI in Europe and Lake Baikal, but causes a significant decrease in Siberia; the physical mechanisms involved in this relationship are then investigated. A positive phase of WAPVI leads to anomalies in surface air temperature and rainfall over Eurasia, which then induces a significant decrease in snow cover and snow depth in Europe and Lake Baikal and an increase of snow depth in Siberia. The colder ground temperature in Siberia during spring is considered responsible for the stronger snow depth and weaker vegetation growth in this region. The weaker and thinner snow cover in Europe and Baikal produces a decrease in albedo and an increase in heat. Thin snow melts fast in the following spring and land releases more heat to the atmosphere; consequently, warm and moist land surface facilitates vegetation growth in Europe and the Baikal regions during positive WAPVI years. In addition, WAPVI can induce sea surface temperature (SST) anomalies in the North Atlantic, which displays a tripole pattern similar to that of the empirical mode pattern in winter. Furthermore, the SST anomalous pattern persisting from winter to spring can trigger a stationary wave-train propagating from west to east in boreal Eurasia, with "negative-positive-negative-positive" geopotential height anomalies, which further exerts an impact on vegetation growth through modulation of the heat balance.

  7. Integrated Paleomagnetism and U-Pb Geochronology of Mafic Dikes of the Eastern Anabar Shield Region, Siberia: Implications for Mesoproterozoic Paleolatitude of Siberia and Comparison with Laurentia.

    Science.gov (United States)

    Ernst; Buchan; Hamilton; Okrugin; Tomshin

    2000-07-01

    This article reports the first joint paleomagnetic and U-Pb geochronologic study of Precambrian diabase dikes in the Anabar Shield and adjacent Riphean cover of Siberia. It was undertaken to allow comparison with similar published studies in Laurentia and to test Proterozoic reconstructions of Siberia and Laurentia. An east-trending Kuonamka dike yielded a provisional U-Pb baddeleyite emplacement age of 1503+/-5 Ma and a virtual geomagnetic pole at 16 degrees S, 221 degrees E (dm=17&j0;, dp=10&j0;). A paleomagnetic pole at 6 degrees N, 234 degrees E (dm=28&j0;, dp=14&j0;) was obtained from five Kuonamka dikes. An east-southeast-trending Chieress dike yielded a U-Pb baddeleyite emplacement age of 1384+/-2 Ma and a virtual geomagnetic pole at 4 degrees N, 258 degrees E (dm=9&j0;, dp=5&j0;). Kuonamka and Chieress poles are interpreted to be primary but do not average out secular variation. Assuming that the Siberian Plate has remained intact since the Mesoproterozoic, except for mid-Paleozoic opening of the Viljuy Rift, then the above results indicate that the Siberian Plate was in low latitudes at ca. 1503 and 1384 Ma, broadly similar to low latitudes determined for Laurentia from well-dated paleopoles at 1460-1420, 1320-1290, and 1267 Ma. This would allow Laurentia and Siberia to have been attached in the Mesoproterozoic, as suggested in several recent studies based on geological criteria. However, because paleomagnetic results from the Anabar Shield region do not average out secular variation and the ages of poles from Siberia and Laurentia are not well matched, it is not yet possible to distinguish between these reconstructions or to rule out other configurations that also maintain the two cratons at low paleolatitudes.

  8. Analysis of naticid gastropod predation across the trans-Arctic invasion in the Tjörnes beds, Iceland, and the Red Crag Formation, East Anglia, England

    Science.gov (United States)

    Neely, Samuel H.; Kelley, Patricia H.

    2016-04-01

    Invasive species are wreaking havoc on modern ecosystems; however, species invasions are not new threats to ecosystems. The fossil record allows conservationists to acquire deep-time perspectives on long-term effects of natural invasions before anthropogenic impacts. Drill holes from invasive naticid gastropod predators on bivalve prey can be quantified to provide evidence of the impact of these invasive predators on ecosystems. An asymmetrical faunal interchange, known as the trans-Arctic invasion (TAI), occurred between the Pacific and Atlantic oceans during the Pliocene (˜3.5 Ma) because of the opening of the Bering Strait. This interchange could have changed naticid gastropod drilling predation on bivalves due to the migration of Pacific fauna into the Atlantic Ocean. The Tjörnes locality of northeast Iceland well characterizes the TAI because this site has preserved genera in three distinct levels that divide the invasion into the pre-invasion (Tapes and Mactra zones) and the post-invasion (Serripes zone). Temporal comparisons can be made between these pre- and post-invasion zones to analyze drilling predation across the TAI. Spatial comparisons of drilling predation in the post-invasion deposits can be made by correlating the Serripes zone (3.6-2.6 Ma) to the Red Crag Formation (2.54 Ma) of East Anglia, England, because these localities are of similar age and contain similar taxa. Specimens from the Tjörnes Beds, Iceland, were analyzed in collections housed at the Icelandic Institute of Natural History. Red Crag Formation specimens were analyzed at the Academy of Natural Sciences at Drexel University, Philadelphia, PA. Height and length of bivalve specimens were measured. The occurrence of complete and incomplete (unsuccessful) drill holes and drill hole diameter were recorded for all whole bivalves. Drilling frequency (DF = % mortality) and prey effectiveness (PE = % of attempted drill holes that were incomplete) were calculated. Icelandic samples

  9. Provenance trials of larch in Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Milyutin, L.I. [V.N. Sukachev Inst. of Forest SB RAS, Krasnoyarsk (Russian Federation)

    1995-12-31

    Some results of provenance trials of larch in Siberia are given. These provenance trials were established in the last thirty years by efforts of V.N. Sukaczev Inst. of Forest. Provenances and species of larch were tested in some field trials distributed over Siberia between Lat. N 52 deg and 66 deg, Long. E 88 deg and 113 deg: near Krasnoyarsk, in Republic Khakasia (an altitudes of 800 and 1200 metres), in the Lower Yenisei near Turukhansk, in the west and south regions of Krasnoyarsk territory, in the Upper Lena, near Chita. 2 refs

  10. Glaciation of West Siberia – disputable questions and means of their solution

    Directory of Open Access Journals (Sweden)

    V. S. Sheinkman

    2015-01-01

    Full Text Available Different approaches to the problem of Quaternary glaciation of the North-West Siberia have been considered in the present paper, in which also analysis of glaciological situation has been done for the region. New obtained materials are given to show evidence of ancient glaciation in the Near-Ural region. As well the middle reach of the Ob’ River along its right-hand bank has been elucidated. The stated data have clearly demonstrated that diverse geological processes occurred to form the Quaternary deposits in the North-West Siberia. Partly it was an activity of glaciers advanced to the lowland from the centers of glaciation in the surrounding mountains. A role of not small importance belonged also to tectonic processes, which Ob’ erosion-accumulative influence and sea transgressions from the Arctic Ocean were connected with. At that all these occurred at the background of deep rock freezing. Study of moraines along the whole length of valleys from the ends of the modern glaciers until the formations of the maximal advance of ancient glaciers confirm our previous conclusion that glaciation also in this part of Siberia could be morphologically of a mountain-valley form only. Developing under conditions of strong permafrost and cryoaridization, the Pleistocene glaciers in the North-West Siberia concentrated in its mountains and did not advance farther than to the foothills. The upland of Siberian Uval, which sometimes has been considered as a moraine relic, presents another formation. It is a completely built system of Ob’ terraces representing the blocks of uplift deposits elevated by tectonics along the renewed ancient faults. The conclusion demonstrates that the subsequent spread of the stone moraine material happened as a result of movement of icebergs which broke of the glaciers with the trapped rock debris during sea transgressions from the Arctic Ocean. It has been established that, according to the results of absolute dating of the

  11. Arctic shipping and China : Governance structure and future developments

    OpenAIRE

    Hjalti Þór Hreinsson 1984

    2014-01-01

    The goal of this thesis is to study China’s shipping ambitions in the Arctic and the pertinent governing instruments. Arctic shipping poses significant challenges for Arctic governance with increased access to its oceans for shipping companies. Arctic transit is driven by demanding world markets in the West and the rising economic powers of the East, looking for the most cost-efficient routes. Rapid ice melt leads to better access for vessels, but other obstacles await those interested in Arc...

  12. Utilization of ancient permafrost carbon in headwaters of Arctic fluvial networks

    OpenAIRE

    Paul J. Mann; Eglinton, Timothy I.; Mcintyre, Cameron P.; Zimov, Nikita; Davydova, Anna; Vonk, Jorien E.; Holmes, Robert M.; Spencer, Robert G.M.

    2015-01-01

    Northern high-latitude rivers are major conduits of carbon from land to coastal seas and the Arctic Ocean. Arctic warming is promoting terrestrial permafrost thaw and shifting hydrologic flowpaths, leading to fluvial mobilization of ancient carbon stores. Here we describe 14 C and 13 C characteristics of dissolved organic carbon from fluvial networks across the Kolyma River Basin (Siberia), and isotopic changes during bioincubation experiments. Microbial communities utilized ancient carbon (1...

  13. Paleoenvironmental dynamics of Western Beringia - New studies from the Yedoma key site Duvanny Yar (Lower Kolyma River, Siberia)

    Science.gov (United States)

    Strauss, Jens; Schirrmeister, Lutz; Wetterich, Sebastian

    2010-05-01

    Duvanny Yar is a stratigraphic key site for the late Quaternary in Western Beringia. It is characteristic for ice-rich permafrost sequences of the so-called Yedoma Suite in north-east Siberia (e.g. KAPLINA et al. 1978; SHER et al. 1979) and is an important reference site for the late Pleistocene history of Beringia (HOPKINS 1982). The aim of our study was to reconstruct the paleoenvironmental dynamics at the Duvanny Yar site during the late Quaternary using its terrestrial archive. A multidisciplinary approach using geocryological, geochronological, sedimentological, hydrochemical, isotope geochemical, and paleoecological methods was applied to obtain multiproxy records. Sediment samples were analysed for ice contents, grain size parameters, biogeochemistry (total carbon, total organic carbon, total nitrogen, stable carbon isotopes), mineral density, mass specific magnetic susceptibility, and for radiocarbon age. Stable isotopes of water were measured for ground ice (ice wedges, segregated ice, and pore ice), modern surface waters and modern precipitation. Six profiles along the riverbank were sampled in August 2008. They contained Eemian lacustrine deposits, long sequences of Ice Complex deposits of the Late Pleistocene Yedoma, Holocene lacustrine and boggy deposits in thermokarst depressions. All profiles showed very bad sorted sediment of fine to coarse silt. A homogenous and polymodal grain size distribution for the ice rich (~30 to 60 wt %) Yedoma Suite revealed a polygenetic origin and disproves the pure "arctic loess" hypothesis for these deposits. Measurements of bulk density, ice content and total organic carbon content (TOC) enable for a relative TOC content in Ice Complex deposits at Duvanny Yar. The mean value of organic carbon at Duvanny Yar is 16 ± 11 kg/m^3. Geochronological results based on 11 new AMS ages revealed that the Yedoma Suite was continuously formed from the end of the Middle Weichselian (~ 40000 years BP) and at least until the Late

  14. Teleseismic receiver functions imaging of Siberia

    DEFF Research Database (Denmark)

    Soliman, Mohammad Youssof Ahmad; Thybo, Hans; Artemieva, Irina

    2014-01-01

    We map the lithosphere in Siberia by using the available broadband seismic data for calculation of Ps- and Sp-wave receiver functions (RF). RFs show converted waves from discontinuities in the vicinity of the seismic stations. The main objective is to image the Moho and upper mantle discontinuities...

  15. Distribution and numbers of breeding ivory gulls Pagophila eburnea in Severnaja Zemlja, Russian Arctic

    NARCIS (Netherlands)

    Volkov, AE; de Korte, J.

    1996-01-01

    The ivory gull Pagophila eburnea has a semi-circumpolar distribution with breeding sites in the High Arctic. Data about ivory gulls in the Severnaja Zemlja Archipelago (Siberia) were collected from 1991 to 1995. The numbers of breeding ivory gulls and their egg-laying period are correlated with the

  16. Patterns in the distribution of Arctic freshwater zooplankton related to glaciation history

    DEFF Research Database (Denmark)

    Samchyshyna, Larysa; Hansson, L. A.; Christoffersen, Kirsten Seestern

    2008-01-01

    We analysed circumpolar samples from 68 lakes within the 10 degrees C-July isotherm from Arctic Canada, Nunavut, Greenland, Svalbard, Eastern Siberia, the Beringia region, and Alaska. In total, we found 3 species of Anostraca, 17 of Diplostraca, 1 species of cyclopoid and 14 species of calanoid...

  17. Recent ecohydrological change in relation to permafrost degradation in eastern Siberia

    Science.gov (United States)

    Iijima, Y.; Fedorov, A. N.; Maximov, T. C.

    2010-12-01

    Recently, our continuous observations during the last decade revealed considerable evidence of abrupt land surface moistening and synchronized rapid soil warming within active layer and upper part of permafrost in the central Lena River basin in eastern Siberia. The present study focuses firstly on the linkage between atmospheric and land surface variations in eastern Siberia in terms of the hydrothermal variations within the surface layer of the permafrost and influence of storm track activity in Arctic during pre-winter and snow start season and moreover on the linkage between the permafrost degradation and ecohydrological change in this region. We utilized soil temperature, moisture and active layer thickness data from the observational network in the left and right banks of the Lena River in the Yakutsk area. Daily data of precipitation and snow depth and reanalysis dataset were used to analyze the large-scale atmospheric fields and determine storm-track activity. The peculiar feature of the warming is that the soil moisture correspondingly increases within the active layer observed at many sites in the Yakutsk area. This hydro-thermal change is primarily due to wetting climate conditions rather than atmospheric warming with abnormally large amounts of winter snow accumulation and summer precipitation in the central and southern part of the Lena River basin. The wetting conditions in eastern Siberia are likely due to enhancement of cyclonic anomaly over the Arctic Ocean and eastward propagation of storm activities in summer and early winter. Water vapor flux from Pacific side (Okhotsk sea) was enhanced in conjunction with the manifested precipitation over the eastern Siberia. As results, consecutive positive anomalies of winter snow accumulation and next summer precipitation which had seldom occurred in the second half of the last century in eastern Siberia effectively humidified land surface on the permafrost region after 2005 resulting abrupt soil warming in

  18. Productivity, chlorophyll a, Photosynthetically Active Radiation (PAR) and other phytoplankton data from the Arctic Ocean, Bering Sea, Chukchi Sea, Beaufort Sea, East Siberian Sea, Kara Sea, Barents Sea, and Arctic Archipelago measured between 17 April, 1954 and 30 May, 2006 compiled as part of the Arctic System Science Primary Production (ARCSS-PP) observational synthesis project (NODC Accession 0063065)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Arctic Ocean primary production data were assembled from original input data archived in various international databases, provided by individual investigators or in...

  19. Arctic methane

    NARCIS (Netherlands)

    Dyupina, E.; Amstel, van A.R.

    2013-01-01

    What are the risks of a runaway greenhouse effect from methane release from hydrates in the Arctic? In January 2013, a dramatic increase of methane concentration up to 2000 ppb has been measured over the Arctic north of Norway in the Barents Sea. The global average being 1750 ppb. It has been sugges

  20. 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...

  1. Mechanism of seasonal Arctic sea ice evolution and Arctic amplification

    Science.gov (United States)

    Kim, Kwang-Yul; Hamlington, Benjamin D.; Na, Hanna; Kim, Jinju

    2016-09-01

    Sea ice loss is proposed as a primary reason for the Arctic amplification, although the physical mechanism of the Arctic amplification and its connection with sea ice melting is still in debate. In the present study, monthly ERA-Interim reanalysis data are analyzed via cyclostationary empirical orthogonal function analysis to understand the seasonal mechanism of sea ice loss in the Arctic Ocean and the Arctic amplification. While sea ice loss is widespread over much of the perimeter of the Arctic Ocean in summer, sea ice remains thin in winter only in the Barents-Kara seas. Excessive turbulent heat flux through the sea surface exposed to air due to sea ice reduction warms the atmospheric column. Warmer air increases the downward longwave radiation and subsequently surface air temperature, which facilitates sea surface remains to be free of ice. This positive feedback mechanism is not clearly observed in the Laptev, East Siberian, Chukchi, and Beaufort seas, since sea ice refreezes in late fall (November) before excessive turbulent heat flux is available for warming the atmospheric column in winter. A detailed seasonal heat budget is presented in order to understand specific differences between the Barents-Kara seas and Laptev, East Siberian, Chukchi, and Beaufort seas.

  2. Aircraft observations of Asian pollution transported into the Arctic UTLS

    Science.gov (United States)

    Roiger, A.; Schlager, H.; Arnold, F.; Schäfler, A.; Aufmhoff, H.; Cooper, O. R.; Lazzara, M. A.; Stohl, A.; Sodemann, H.; Schiller, C.; Guenther, G.

    2010-12-01

    We present aircraft-borne observations of Asian pollution in the upper troposphere and lowermost stratosphere above Greenland. The measurements were performed within the GRACE campaign (Greenland Aerosol and Chemistry Experiment), a sub-project of the POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport) initiative. The GRACE campaign was conducted in summer 2008 and aimed to study the influence of both boreal forest fire and anthropogenic emissions on the composition of the UT/LS in the summer-time Arctic. We used the DLR Falcon operated from Kangerlussuaq (Greenland) and performed a total of 16 flights up to altitudes of 12 km. Here we focus on measurements of a flight on 10th July 2008, where we probed an air mass with unusually high CO, PAN and H2O mixing ratios of up to 136 nmol mol-1, 350 pmol mol-1 and 80 µmol mol-1, respectively. The air mass was encountered at 11.3 km altitude, well above the dynamical tropopause. In-situ measurements of ozone, NO, and NOy indicate that this layer was a mixed air mass containing both air from the troposphere and stratosphere. Backward tracer and trajectory analysis with FLEXPART and LAGRANTO suggest that we probed the top of a polluted air mass originating from the coastal regions of South East Asia. This anthropogenic pollution experienced strong up-lift to more than 10 km altitude in a warm conveyor belt (WCB) located over the Russian east-coast. Due to a low pressure system moving from Siberia towards Spitsbergen, the polluted air mass was transported across the North Pole into the sampling area, hereby up-lifting the local tropopause by ~2.5 km. Mixing with Arctic stratospheric air most likely took place along the sides of the plume when the tropospheric air mass was stretched into long and narrow filaments. The transport pathway presented in this study could be an important mechanism to bring pollution into the polar lowermost

  3. Impact processes, permafrost dynamics, and climate and environmental variability in the terrestrial Arctic as inferred from the unique 3.6 Myr record of Lake El'gygytgyn, Far East Russia - A review

    Science.gov (United States)

    Wennrich, Volker; Andreev, Andrei A.; Tarasov, Pavel E.; Fedorov, Grigory; Zhao, Wenwei; Gebhardt, Catalina A.; Meyer-Jacob, Carsten; Snyder, Jeffrey A.; Nowaczyk, Norbert R.; Schwamborn, Georg; Chapligin, Bernhard; Anderson, Patricia M.; Lozhkin, Anatoly V.; Minyuk, Pavel S.; Koeberl, Christian; Melles, Martin

    2016-09-01

    Lake El'gygytgyn in Far East Russia is a 3.6 Myr old impact crater lake. Located in an area that has never been affected by Cenozoic glaciations nor desiccation, the unique sediment record of the lake represents the longest continuous sediment archive of the terrestrial Arctic. The surrounding crater is the only impact structure on Earth developed in mostly acid volcanic rocks. Recent studies on the impactite, permafrost, and sediment sequences recovered within the framework of the ICDP "El'gygytgyn Drilling Project" and multiple pre-site surveys yielded new insight into the bedrock origin and cratering processes as well as permafrost dynamics and the climate and environmental history of the terrestrial Arctic back to the mid-Pliocene. Results from the impact rock section recovered during the deep drilling clearly confirm the impact genesis of the El'gygytgyn crater, but indicate an only very reduced fallback impactite sequence without larger coherent melt bodies. Isotope and element data of impact melt samples indicate a F-type asteroid of mixed composition or an ordinary chondrite as the likely impactor. The impact event caused a long-lasting hydrothermal activity in the crater that is assumed to have persisted for c. 300 kyr. Geochemical and microbial analyses of the permafrost core indicate a subaquatic formation of the lower part during lake-level highstand, but a subaerial genesis of the upper part after a lake-level drop after the Allerød. The isotope signal and ion compositions of ground ice is overprinted by several thaw-freeze cycles due to variations in the talik underneath the lake. Modeling results suggest a modern permafrost thickness in the crater of c. 340 m, and further confirm a pervasive character of the talik below Lake El'gygytgyn. The lake sediment sequences shed new leight into the Pliocene and Pleistocene climate and environmental evolution of the Arctic. During the mid-Pliocene, significantly warmer and wetter climatic conditions in

  4. Japan’s need for Russian oil and gas: A shift in energy flows to the Far East

    International Nuclear Information System (INIS)

    This article examines the choices of Japan’s governmental institutions vis-à-vis Russian supplies of oil and gas. First, there is a perceived need to diversify the sources of crude oil in order to avoid too much reliance on the Middle East. Following the inauguration of the Sakhalin oil projects and completion of the ESPO pipeline, Russian crude oil is nearing a 10% share in the Japanese market. It is suggested that Russian crude oil supplies have been chosen due to their proximity, safety and flexibility, and their positive effect on Japan’s bargaining power in relation to crude suppliers in the Middle East. Second, Japan’s shift from nuclear to LNG in power generation after the Fukushima accident in March 2011 increased LNG imports by 25% in just two years. While Qatar expanded its market share the most, Russia also gained, even though it only had one operational LNG project in Sakhalin-2. Russian companies are now working on several LNG projects in Northeast Asia and the Arctic region. However, the resumption of nuclear power in Japan might have a negative impact on new Russian LNG projects. - Highlights: • Russia’s oil export will gain a 10% share in Japan. • Russian companies are accelerating several LNG projects in NE Asia. • Japan’s exploration activity in East Siberia has reached the investment stage

  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. Technical-Environmental Permafrost Observatories (TEPO) of northern West Siberia

    Science.gov (United States)

    Kurchatova, A. N.; Griva, G. I.; Osokin, A. B.; Smolov, G. K.

    2005-12-01

    During the last decade one of the most developed topics in environmental studies was the effect of global climate change. This has been shown to be especially pronounced in northern regions, having an important influence on the subsequent transformation of frozen soil distribution and potential permafrost degradation. In West Siberia such studies are especially important with the prospect of plans for development of oil-gas fields (Yamal, Gydan and Kara Sea shelf). Presently the enterprises independently determine the necessary research for ecological control of the territory. Therefore, the Tyumen State Oil and Gas University (TSOGU) together with one of the leading gas enterprises "Nadymgasprom" started to create an observational network along the meridian transect of northern West Siberia (Yamal-Nenets administrative district). Observational network consists from a number of monitoring sites - Technical-Environmental permafrost Observatories (TEPO). The research complex includes temperature observations in boreholes (depths of 30) equipped with automatic systems for registration and data collection; seasonal field investigations on spatial distribution and temporal variability of the snow cover and vegetation and soil distribution. TSOGU and "Nadymgasprom" plan for the realization of long-term monitoring to obtain representative results on permafrost-climate interaction. At present there are three monitoring observatories located in the main landscape types and gas fields in use since 1972 (Medvezhye), 1992 (Yubileynoe) and in development (Harasavey). The next contribution to International Polar Year (2007-2008) will be renewal of one of the former monitoring sites (established in 1972) with a long-term period of observation and creation of a new site at the Yamal peninsula (Arctic tundra zone). At the last site the installation of an automatic Climate-Soil Station is being planned in the framework of the INTAS Infrastructure Action project with cooperation of

  7. Temporal Behavior of Lake Size-Distribution in a Thawing Permafrost Landscape in Northwestern Siberia

    Directory of Open Access Journals (Sweden)

    Johanna Mård Karlsson

    2014-01-01

    Full Text Available Arctic warming alters regional hydrological systems, as permafrost thaw increases active layer thickness and in turn alters the pathways of water flow through the landscape. Further, permafrost thaw may change the connectivity between deeper and shallower groundwater and surface water altering the terrestrial water balance and distribution. Thermokarst lakes and wetlands in the Arctic offer a window into such changes as these landscape elements depend on permafrost and are some of the most dynamic and widespread features in Arctic lowland regions. In this study we used Landsat remotely sensed imagery to investigate potential shifts in thermokarst lake size-distributions, which may be brought about by permafrost thaw, over three distinct time periods (1973, 1987–1988, and 2007–2009 in three hydrological basins in northwestern Siberia. Results revealed fluctuations in total area and number of lakes over time, with both appearing and disappearing lakes alongside stable lakes. On the whole basin scales, there is no indication of any sustained long-term change in thermokarst lake area or lake size abundance over time. This statistical temporal consistency indicates that spatially variable change effects on local permafrost conditions have driven the individual lake changes that have indeed occurred over time. The results highlight the importance of using multi-temporal remote sensing data that can reveal complex spatiotemporal variations distinguishing fluctuations from sustained change trends, for accurate interpretation of thermokarst lake changes and their possible drivers in periods of climate and permafrost change.

  8. Feedback Attributions to the Interannual Variation of the Dominant Modes of the East Asian Winter Monsoon

    Science.gov (United States)

    Li, Yana; Yang, Song

    2016-04-01

    This study investigates the interannual variation and feedback attributions of the East Asian Winter Monsoon for the period of 1979-2013. The variations of winter mean surface air temperature are dominated by two distinct principal modes, which account for 70.9% of the total variance. The interannual variation of the northern mode features high correlations with the variations of the Arctic Oscillation, the Siberia High, and the tropoical Indian Ocean Dipole, while the southern mode is strongly linked to the East Asia trough and the atmospheric circulation over the northwestern Pacific. To find the main factors which affect the two different modes, this study decomposes the surface air temperature interannual variation into various feedback attributions by applying a climate feedback-response analysis method. The results indicate that the surface cooling associated with the northern mode is mainly contributed by the feedback processes of atmospheric dynamics, cloud, and sensible heating. For the southern mode, the surface cooling is mainly attributed to the atmospheric dynamic process, sensible heating, and water vapor, while the oceanic dynamics and heat storage process induces a negative effect that warms the surface.

  9. New Paleomagnetic Justification for the Plate Tectonic Reconstruction of the Arctic

    Science.gov (United States)

    Metelkin, D. V.; Vernikovskiy, V. A.; Matushkin, N. Y.; Zhdanova, A.; Mikhaltsov, N. E.; Abashev, V. V.; Kulakov, E.

    2015-12-01

    We report paleomagnetic and geologic data that support a new plate tectonic reconstruction for the Arctic from the Neoproterozoic to Mesozoic. We propose a new outlook on the history of the Arctida paleocontinent, which combined sialic blocks of the present Eurasian shelf of the Arctic Ocean. Our model implies two Arctidas at that time. The earlier Arctida-I was located near equator and connected the continental margins of Laurentia, Baltica and Siberia within the supercontinent of Rodinia. The Arcrtida-I disintegration was caused by a breakup of Rodinia. As a result, small plates like on Svalbard, Kara, New Siberia Island (NSI) terrane and others were formed. We have reconstructed the main stages of later remobilization and global drift of these plates before Pangea assemblage. In contrast to traditional interpretation of the NSI as a part of the Chukchi-Alaska terrane, our observation suggest a linkage between the NSI and Kolyma-Omolon terrane that framed Siberia. As a result of Pangea assembly at Paleozoic-Mesozoic boundary the second recovery of Arctida took place. We assume that Arctida-II also connected Laurentia, Baltica, and Siberia but constituted the Pangean periphery in the temperate latitudes. The later Arctida-II disintegrated during the Mesozoic during the opening of Arctic Ocean.

  10. BRDF characteristics of tundra vegetation communities in Yamal, Western Siberia

    Science.gov (United States)

    Buchhorn, Marcel; Heim, Birgit; Walker, Donald A. Skip; Epstein, Howard; Leibman, Marina

    2013-04-01

    Satellite data from platforms with pointing capabilities (CHRIS/Proba, RapidEye) or from sensors with wide swath (AVHRR, MODIS, MERIS) is influenced by the bidirectional reflectance distribution function (BRDF). This effect can cause significant changes in the measured spectral surface reflectance depending on the solar illumination geometry and sensor viewing conditions. The Environmental Mapping and Analysis Program (EnMAP), a German hyperspectral mission with expected launch in 2016, will provide high spectral resolution observations with a ground sampling distance of 30 meters. Since the EnMAP sensor has pointing capabilities, both spectral and directional reflection characteristics need to be taken into account for the algorithms development for vegetation parameters. The 'hyperspectral method development for Arctic VEGetation biomes' (hy-Arc-VEG) project is part of the national preparation program for the EnMAP mission. Within the EnMAP projcect hy-Arc-VEG we developed a portable field spectro-goniometer, named ManTIS (Manual Transportable Instrument for Spherical BRDF observations), for the in-situ measurements of anisotropic effects of tundra surfaces (national and international patent pending - DE 102011117713.6). The goniometer was designed for field use in difficult as well as challenging terrain and climate. It is therefore of low weight, without electrical devices and weatherproof. It can be disassembled and packed into small boxes for transport. The current off-nadir viewing capacity is matched to the EnMAP sensor configuration (up to 30°). We carried out spectral field and goniometer measurements on the joint YAMAL 2011 expedition (RU-US-DE) organized by the Earth-Cryosphere Institute (ECI) in August 2011 on the Yamal Peninsula, northwestern Siberia, Russia. The field goniometer measurements (conducted under varying sun zenith angles) as well as field spectro-radiometrical measurements were carried out at the NASA Yamal Land Cover/Land Use Change

  11. Satellite observations of long range transport of a large BrO plume in the Arctic

    Directory of Open Access Journals (Sweden)

    M. Begoin

    2010-07-01

    Full Text Available Ozone Depletion Events (ODE during polar springtime are a well known phenomenon in the Arctic and Antarctic boundary layer. They are caused by the catalytic destruction of ozone by halogens producing reactive halogen oxides like bromine monoxide (BrO. The key halogen bromine can be rapidly transferred into the gas phase in an autocatalytic process – the so called "Bromine Explosion". However, the exact mechanism, which leads to an initial bromine release as well as the influence of transport and chemical processes on BrO, is still not clearly understood.

    In this study, BrO measurements from the satellite instrument GOME-2 are used together with model calculations with the dispersion model FLEXPART to study an arctic BrO event in March 2007, which could be tracked over several days and a large area. Full BrO activation was observed within one day east of Siberia with subsequent transport to Hudson Bay. The event was linked to a cyclone with very high surface wind speeds, which could have been involved in the production and lifting of aerosols or blowing snow. Considering the short life time of BrO, transported aerosols or snow can also provide the surface for BrO recycling within the plume for several days. The evolution of the BrO plume could be reproduced by FLEXPART simulations of a passive tracer indicating that the activated air mass was transported all the way from Siberia to Hudson Bay. To localise the most probable transport height, model runs initialised in different heights have been performed showing similar transport patterns throughout the troposphere but best agreement with the measurements between the surface and 3 km. The influence of changes in tropopause height on measured BrO values has been considered, but cannot completely explain the observed high BrO values. Backward trajectories from the area of BrO initialisation show upward lifting from the surface up to 3 km and no indication for intrusion of stratospheric

  12. Larch Forests of Middle Siberia: Long-Term Trends in Fire Return Intervals

    Science.gov (United States)

    Kharuk, Viacheslav I.; Dvinskaya, Mariya L.; Petrov, Ilya A.; Im, Sergei T.; Ranson, Kenneth J.

    2016-01-01

    Fire history within the northern larch forests of Central Siberia was studied (65+degN). Fires within this area are predominantly caused by lightning strikes rather than human activity. Mean fire return intervals (FRIs) were found to be 112 +/- 49 years (based on firescars) and 106 +/- 36 years (based on firescars and tree natality dates). FRIs were increased with latitude increase and observed to be about 80 years at 64N, about 200 years near the Arctic Circle and about 300 years nearby the northern range limit of larch stands (approx.71+degN). Northward FRIs increase correlated with incoming solar radiation (r = -0.95). Post- Little Ice Age (LIA) warming (after 1850) caused approximately a doubling of fire events (in comparison with a similar period during LIA). The data obtained support a hypothesis of climate-induced fire frequency increase. Keywords Fire ecology Fire history Fire frequency Siberian wildfires Larch forests Climate change

  13. Levoglucosan indicates high levels of biomass burning aerosols over oceans from the Arctic to Antarctic

    Science.gov (United States)

    Hu, Q.; Xie, Z.; Wang, X.; Kang, H.; Zhang, P.

    2015-12-01

    Biomass burning discharges numerous kinds of gases and aerosols, such as carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), black carbon (BC), alcohols, organic acids and persistent organic pollutants (POPs), and is known to affect air quality, global carbon cycle, and climate. However, the extent to which biomass burning gases/aerosols are present on a global scale, especially in the marine atmosphere, is poorly understood. Here we measure levoglucosan, a superior molecular tracer of biomass burning aerosols because of its single source, in marine air from the Arctic Ocean through the North and South Pacific Ocean to coastal Antarctica during burning season. Levoglucosan was found to be present in all regions at ng/m3 levels. As a whole, levoglucosan concentrations in the Southern Hemisphere were comparable to those in the Northern Hemisphere. Marine air in the mid-latitudes (30°-60° N and S) has the highest levoglucosan loading due to the emission from adjacent lands. Air over the Arctic Ocean which affected by biomass burning in the east Siberia has intermediate loading. Equatorial latitudes is the main source of biomass burning emissions, however, levoglucosan is in relatively low level. Large amount of precipitation and high hydroxyl radical concentration in this region cause more deposition and degradation of levoglucosan during transport. Previous studies were debatable on the influence of biomass burning on the Antarctic because of uncertain source of BC. Here via levoglucosan, it is proved that although far away from emission sources, the Antarctic is still affected by biomass burning aerosols which may be derived from South America. Biomass burning has a significant impact on mercury (Hg) and water-soluble organic carbon (WSOC) in marine aerosols from pole to pole, with more contribution to WSOC in the Northern Hemisphere than in the Southern Hemisphere.

  14. Systematics and biology of some species of Micrurapteryx Spuler (Lepidoptera, Gracillariidae) from the Holarctic Region, with re-description of M. caraganella (Hering) from Siberia.

    Science.gov (United States)

    Kirichenko, Natalia; Triberti, Paolo; Mutanen, Marko; Magnoux, Emmanuelle; Landry, Jean-François; Lopez-Vaamonde, Carlos

    2016-01-01

    During a DNA barcoding campaign of leaf-mining insects from Siberia, a genetically divergent lineage of a gracillariid belonging to the genus Micrurapteryx was discovered, whose larvae developed on Caragana Fabr. and Medicago L. (Fabaceae). Specimens from Siberia showed similar external morphology to the Palearctic Micrurapteryx gradatella and the Nearctic Parectopa occulta but differed in male genitalia, DNA barcodes, and nuclear genes histone H3 and 28S. Members of this lineage are re-described here as Micrurapteryx caraganella (Hering, 1957), comb. n., an available name published with only a brief description of its larva and leaf mine. Micrurapteryx caraganella is widely distributed throughout Siberia, from Tyumen oblast in the West to Transbaikalia in the East. Occasionally it may severely affect its main host, Caragana arborescens Lam. This species has been confused in the past with Micrurapteryx gradatella in Siberia, but field observations confirm that Micrurapteryx gradatella exists in Siberia and is sympatric with Micrurapteryx caraganella, at least in the Krasnoyarsk region, where it feeds on different host plants (Vicia amoena Fisch. and Vicia sp.). In addition, based on both morphological and molecular evidence as well as examination of type specimens, the North American Parectopa occulta Braun, 1922 and Parectopa albicostella Braun, 1925 are transferred to Micrurapteryx as Micrurapteryx occulta (Braun, 1922), comb. n. with albicostella as its junior synonym (syn. n.). Characters used to distinguish Micrurapteryx from Parectopa are presented and illustrated. These findings provide another example of the potential of DNA barcoding to reveal overlooked species and illuminate nomenclatural problems. PMID:27110203

  15. Annual and latitudinal variations of surface fluxes and meteorological variables at Arctic terrestrial sites

    Science.gov (United States)

    Grachev, Andrey; Uttal, Taneil; Persson, Ola; Konopleva-Akish, Elena; Crepinsek, Sara; Cox, Christopher; Fairall, Christopher; Makshtas, Alexander; Repina, Irina

    2016-04-01

    This study analyzes and discusses seasonal and latitudinal variations of surface fluxes (turbulent, radiative, and soil ground heat) and other ancillary surface/snow/permafrost data based on in-situ measurements made at two long-term research observatories near the coast of the Arctic Ocean located in Canada and Russia. The hourly averaged data collected at Eureka (Canadian territory of Nunavut) and Tiksi (East Siberia) located at two quite different latitudes (80.0 N and 71.6 N respectively) are analyzed in details to describe the seasons in the Arctic. Although Eureka and Tiksi are located at the different continents and at the different latitudes, the annual course of the surface meteorology and the surface fluxes are qualitatively very similar. The air and soil temperatures display the familiar strong seasonal trend with maximum of measured temperatures in mid-summer and minimum during winter. According to our data, variation in incoming short-wave solar radiation led the seasonal pattern of the air and soil temperatures, and the turbulent fluxes. During the dark Polar nights, air and ground temperatures are strongly controlled by long-wave radiation associated generally with cloud cover. Due to the fact that in average the higher latitudes receive less solar radiation than lower latitudes, a length of the convective atmospheric boundary layer (warm season) is shorter and middle-summer amplitude of the turbulent fluxes is generally less in Eureka than in Tiksi. However, since solar elevation angle at local midnight in the middle of Arctic summer is higher for Eureka as compared to Tiksi, stable stratification and upward turbulent flux for carbon dioxide is generally did not observed at Eureka site during summer seasons. It was found a high correlation between the turbulent fluxes of sensible and latent heat, carbon dioxide and the net solar radiation. A comprehensive evaluation of energy balance closure problem is performed based on the multi-year data sets

  16. Seismic and electrical work at rivers and lakes of Siberia

    Science.gov (United States)

    Seleznev, V. S.; Soloviev, V. M.; Liseikin, A. V.; Sigonin, P.

    2013-05-01

    In West and East Siberia a great deal of rivers and big lakes are situated. For oil and gas exploration these places hold much promise. It is very difficult to carry out seismic work in these regions, when temperature is fall down below 40 degrees centigrade. It is necessary to pave ways for technical equipment, to organize shooting operations in some cases, that harming ecology of investigated regions. It is well-known, that at seas and big reservoirs seismic works are carried out with use of air guns as sources and floating or ground cables as receivers. There is a special interest to carry out jointly processing and interpretation of seismic survey and electrical data. We should learn how to carry out such researches at rivers, developed a special combined technology on river seismic and electrical works carrying out. Geophysical Survey SB RAS has been carried out seismic and electrical works at rivers and reservoirs of Siberia for more then 20 years. We had to work in conditions, when depth of a reservoir was more then 10 meters or less then 1 meter. It was necessary to work out or adapt some floating equipment, to create air-guns working on light depths ("Malysh", "Sibiryak"), to create new recording equipment (seismic and electrical variants of "Baikal" equipment) for carrying out work in such conditions. There are presented the results of seismic researches, carried out in the Lake Baikal, Lake Teletskoe. For the first time it was determined, that the depth of sedimentary cover under Lake Baikal exceeds 14 km. On demands of government and private companies we carried out river works in Common-depth-point method at such rivers as: Ob, Volga, Enisey, Vakh, Lena, Kirenga, Nizhnya Tunguska. Comparison of results got at river profiles with surface ones, crossing the river, showed in difficult surface conditions (central part of the River Lena, the Nizhnya Tunguska) river seismic sections are better then surface sections. It is connected with the fact, that

  17. 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

  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. 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

  19. The First Paleomagnetic data from the Cambrian basalts of Henrietta Island (De Long Archipelago, Arctic Ocean)

    Science.gov (United States)

    Metelkin, D. V.; Zhdanova, A.; Vernikovskiy, V. A.; Matushkin, N. Y.

    2015-12-01

    Henrietta Island in De Long archipelago (East-Siberian sea) still remains poorly studied geologically but last investigations show that its volcano-sedimentary sequences can help reconstruct tectonic evolution of East Russian Arctic in Early Paleozoic stage. The deposits lying on Precambrian basements are deformed to varying degrees and intruded by mafic dykes.The study was carried out on two basaltic lava flows whose 40Ar/39Ar age is 520.6±9.5 Ma. Previously the age of these basalts was assumed Cretaceous. According to available data the underlaying sediments contain zircons with Cambrian and Ordovician ages but all boundaries between these basalts and other strata are tectonic. So we suppose the age of basalts as Middle Cambrian but more precise geochronological data are required. All magnetic measurements were performed at the Laboratory of Geodynamics and Paleomagnetism of Institute of Petroleum Geology and Geophysics (Novosibirsk). Basalt samples has relatively high magnetic susceptibility values varying from 5x10-4 to 180x10-4SI units. NRM values range is from 3 to 170 mA/m. Petromagnetic parameters including also coercive characteristics point at the good potentially preserving primary magnetization. Stepwise thermal demagnetization permits to isolate characteristic components of magnetization and calculate mean directions in two lava flows: 1. Ds=294.3°, Is=29.1°, K=81.1, α95=5.1; 2. Ds=301.0°, Is=28.3°, K=34.4, α95=7.9). The mean paleomagnetic pole has coordinates: Plat=20.9°, Plong = 42.6°, dp/dm=14.3/7.9. Paleolatitude was defined as 15.3° but the question of the hemisphere for De Long Islands is open yet. In case of south hemisphere in Middle Cambrian according to available paleomagnetic data De Long islands could be placed close to Taimyr margin of Siberia and in case of northern hemisphere they may be located near south (in present-day coordinates) margin of Siberia. The work was supported by grant RFBR 14-05-31399 and Russian Research Fund

  20. Storage and turnover of organic matter fractions along a Siberian Arctic soil transect

    Science.gov (United States)

    Gentsch, Norman; Mikutta, Robert; Shibistova, Olga; Guggenberger, Georg

    2013-04-01

    Recent observation and climate models demonstrate that arctic ecosystems are already affected by climate warming, as revealed by continuous permafrost degradation and increase of active layer depths. Variations of organic matter (OM) storage in different soil horizons and the OM quality are likely the major drivers of trace gas emissions to the atmosphere. A better understanding of the biogeochemical cycling of OM in permafrost environments is the key to predict future climate changes and the role of terrestrial arctic regions. This study investigates the storage and turnover patterns of OM in functionally different pools, i.e., in particulate plant debris, extractable-water-soluble OM, and mineral-associated OM in permafrost soils along a West-East Siberian transect in the Russian Arctic. We quantified the stocks of total soil organic C (OC) and the respective OM fractions for the first soil meter. Furthermore, we estimated their apparent 14C ages by accelerator mass spectrometry, and determined the mineralization rates and bioavailability of particulate, mineral-bound, and bulk OM in a 90-day incubation experiment. Particulate OM was separated from the mineral-associated OM fraction by density fractionation with sodium polytungstate (density cut-off 1.6 g cm-3) and the OM liberated by this treatment was quantified. Considerable differences in OM storage existed from the West- to the East Siberian Arctic. Cryosols of the Central- and East Siberian sampling sites stored on average 56% more OC than those in West Siberia (25 ± 7 kg m-2versus 11 ± 4 kg m-2 to 1 m soil depth). However, the proportion of the three OM fractions to total OM was similar among the sites. In mineral soil horizons, on average, 17 ± 5% of the total OM was particulate OM, 61 ± 10% was associated with minerals, and 21 ± 3% could be mobilized in dissolved forms during density fractionation. Except for West Siberian soils, ~30% of the OM of the first soil meter was stored in permafrost while

  1. Episodes of cross-polar transport in the Arctic troposphere during July 2008 as seen from models, satellite, and aircraft observations

    Science.gov (United States)

    Sodemann, H.; Pommier, M.; Arnold, S. R.; Monks, S. A.; Stebel, K.; Burkhart, J. F.; Hair, J. W.; Diskin, G. S.; Clerbaux, C.; Coheur, P.-F.; Hurtmans, D.; Schlager, H.; Blechschmidt, A.-M.; Kristjánsson, J. E.; Stohl, A.

    2011-04-01

    During the POLARCAT summer campaign in 2008, two episodes (2-5 July and 7-10 July 2008) occurred where low-pressure systems traveled from Siberia across the Arctic Ocean towards the North Pole. The two cyclones had extensive smoke plumes from Siberian forest fires and anthropogenic sources in East Asia embedded in their associated air masses, creating an excellent opportunity to use satellite and aircraft observations to validate the performance of atmospheric transport models in the Arctic, which is a challenging model domain due to numerical and other complications. Here we compare transport simulations of carbon monoxide (CO) from the Lagrangian transport model FLEXPART and the Eulerian chemical transport model TOMCAT with retrievals of total column CO from the IASI passive infrared sensor onboard the MetOp-A satellite. The main aspect of the comparison is how realistic horizontal and vertical structures are represented in the model simulations. Analysis of CALIPSO lidar curtains and in situ aircraft measurements provide further independent reference points to assess how reliable the model simulations are and what the main limitations are. The horizontal structure of mid-latitude pollution plumes agrees well between the IASI total column CO and the model simulations. However, finer-scale structures are too quickly diffused in the Eulerian model. Applying the IASI averaging kernels to the model data is essential for a meaningful comparison. Using aircraft data as a reference suggests that the satellite data are biased high, while TOMCAT is biased low. FLEXPART fits the aircraft data rather well, but due to added background concentrations the simulation is not independent from observations. The multi-data, multi-model approach allows separating the influences of meteorological fields, model realisation, and grid type on the plume structure. In addition to the very good agreement between simulated and observed total column CO fields, the results also highlight the

  2. Episodes of Cross-Polar Transport in the Arctic Troposphere During July 2008 as Seen from Models, Satellite, and Aircraft Observations

    Science.gov (United States)

    Sodemann, H.; Pommier, M.; Arnold, S. R.; Monks, S. A.; Stebel, K.; Burkhart, J. F.; Hair, J. W.; Diskin, G. S.; Clerbaux, C.; Coheur, P.-F.; Hurtmans, D.; Schlager, H.; Blechschmidt, A.-M.; Kristjansson, J. E.; Stohl, A.

    2011-01-01

    During the POLARCAT summer campaign in 2008, two episodes (2 5 July and 7 10 July 2008) occurred where low-pressure systems traveled from Siberia across the Arctic Ocean towards the North Pole. The two cyclones had extensive smoke plumes from Siberian forest fires and anthropogenic sources in East Asia embedded in their associated air masses, creating an excellent opportunity to use satellite and aircraft observations to validate the performance of atmospheric transport models in the Arctic, which is a challenging model domain due to numerical and other complications. Here we compare transport simulations of carbon monoxide (CO) from the Lagrangian transport model FLEXPART and the Eulerian chemical transport model TOMCAT with retrievals of total column CO from the IASI passive infrared sensor onboard the MetOp-A satellite. The main aspect of the comparison is how realistic horizontal and vertical structures are represented in the model simulations. Analysis of CALIPSO lidar curtains and in situ aircraft measurements provide further independent reference points to assess how reliable the model simulations are and what the main limitations are. The horizontal structure of mid-latitude pollution plumes agrees well between the IASI total column CO and the model simulations. However, finer-scale structures are too quickly diffused in the Eulerian model. Applying the IASI averaging kernels to the model data is essential for a meaningful comparison. Using aircraft data as a reference suggests that the satellite data are biased high, while TOMCAT is biased low. FLEXPART fits the aircraft data rather well, but due to added background concentrations the simulation is not independent from observations. The multi-data, multi-model approach allows separating the influences of meteorological fields, model realisation, and grid type on the plume structure. In addition to the very good agreement between simulated and observed total column CO fields, the results also highlight the

  3. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    Directory of Open Access Journals (Sweden)

    A. Massling

    2012-09-01

    Full Text Available In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81°36' N, 16°40' W in North East Greenland were evaluated for a two-year period from March 2008 to February 2010. Source apportionment using Positive Matrix Factorization (PMF and COnstrained Physical Receptor Model (COPREM was based on measurements of black carbon, elements (Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Zr, Pb and inorganic ions (SO2, SO42−, Na+, NH4+, NO3−, Cl−. In general, source apportionment results by PMF and COPREM showed good agreement. Five sources adequately explained the measurements, which included a Marine and a Soil source of natural origin and three additional anthropogenic sources, which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT model suggested a Canadian Arctic origin, despite certain influences from southern and eastern origins. Another anthropogenic source was characterised by high concentrations of Pb and As, which has been historically referred to as a Combustion source at Station Nord. The impacts of large-scale industry in Siberia, Russia were evident through high Cu concentrations in both the Combustion source and an additional Cu/Ni source. Br correlated well with the anthropogenic species S and Pb though the elements are unlikely to have a common origin. More likely, sulphuric acid aerosols serve as transport containers for Br species of marine or local origin. Of particular relevance to climate, sources of black carbon were identified to be mainly anthropogenic and most probably of Siberian origin (80–98%.

  4. Analysis of Terrestrial Carbon Stocks in a Small Catchment of Northeastern Siberia

    Science.gov (United States)

    Heard, K.; Natali, S.; Bunn, A. G.; Loranty, M. M.; Kholodov, A. L.; Schade, J. D.; Berner, L. T.; Spektor, V.; Zimov, N.; Alexander, H. D.

    2015-12-01

    As arctic terrestrial ecosystems comprise about one-third of the global terrestrial ecosystem carbon total, understanding arctic carbon cycling and the feedback of terrestrial carbon pools to accelerated warming is an issue of global concern. For this research, we examined above- and belowground carbon stocks in a larch-dominated catchment underlain by yedoma and located within the Kolyma River watershed in northeastern Siberia. We quantified carbon stocks in vegetation, active layer, and permafrost, and we assessed the correlation between plant and active layer carbon pools and four environmental correlates — slope, solar insolation, canopy density, and leaf area index ­— at 20 sites. Carbon in the active layer was approximately four times greater than aboveground carbon pools (972 g C m-2), and belowground carbon to 1 m depth was approximately 18 times greater than aboveground carbon pools. Canopy density and slope had a robust positive association with aboveground carbon pools, and soil moisture was positively related to %C in organic, thawed mineral and permafrost soil. Thaw depth was negatively correlated with moss cover and larch biomass, highlighting the importance of vegetation and surface characteristics on permafrost carbon vulnerability. These data suggest that landscape and ecosystem characteristics affect carbon accumulation and storage, but they also play an important role in stabilizing permafrost carbon pools.

  5. Analysis of alcohol dependence in indigenous peoples in Northern Siberia.

    Directory of Open Access Journals (Sweden)

    Michail Savchenko

    2015-06-01

    More severe course of alcoholism among indigenous population of North of Siberia leads to the destruction of traditional lifestyles and reduction of the indigenous population in the northern territories of the Russian Federation.

  6. Flora from the Induan stage (Lower Triassic) of Middle Siberia

    Science.gov (United States)

    Mogucheva, N. K.

    2016-05-01

    The first data on the taxonomic composition of the Induan flora of Siberia are presented. The investigation of Triassic reference sections in northern Siberia (eastern Taimyr, Lena-Anabar Trough, Verkhoyansk region) and correlation with volcano-sedimentary complexes of the Tungus and Kuznetsk basins made it possible to establish for the first time the taxonomic composition of the flora from the Induan Stage of Siberia. Its composition is heterogeneous, forming two large plant formations, which occupied different ecological niches. On the eastern coastal-marine margins of Siberia (eastern Taimyr, Olenek coast, Verkhoyansk region), the Induan flora was largely characterized by lepidophytic ( Tomiostrobus) plants, while in the intracontinental areas (Tungus and Kuznetsk basins, partly Verkhoyansk region), it was characterized by Equisetales-Filicales communities.

  7. Statistical Comparison of Detrital Zircon Suites from the Arctic and Their Bearing on Plate Reconstructions

    Science.gov (United States)

    Soloviev, A. V.; Miller, E. L.

    2010-12-01

    Detrital zircon (DZ) geochronology is a powerful means of establishing paleogeographic ties between regions translated or rifted apart as a consequence of plate motions. The Arctic represents a series of relatively small ocean basins formed in the Cretaceous and Tertiary that rift apart longer established, mostly shelf/shelf basin systems and orogenic belts. Over 87 sets of detrital zircon data (~ 100 grains/sample) are compared and contrasted to each other and to published data using relative age probability distribution diagrams, cumulative age probability curves and the Kolmogorov-Smirnov test. This comparison of data sets help establish major depositional systems, their provenance through time, and how these changed with rifting and accretion events. Late Paleozoic-early Mesozoic siliciclastic strata deposited along the paleo-Pacific margin of Siberia (Verkhoyansk) were transported by the “paleo-Lena” transcontinental river system from the actively deforming southern margin of Siberia into shelf and deep water settings (Prokopiev et al., 2008). Youngest zircons track the depositional ages of host sediments and reflect the tectonic and magmatic history of their source regions. Northern Siberia and platformal upper Paleozoic sections of the New Siberian Islands have similar sources. Importantly, a restricted range of older Precambrian detrital zircon ages (~1.8-2.0 Ga) characterize Paleozoic and Mesozoic strata flanking Siberia. In contrast, a broad Carboniferous-Permian carbonate shelf characterized the Russian Arctic between the Caledonides and the Urals. A ~ 1- 2 Ga range of detrital zircon ages in these samples is characteristic and compatible with derivation or reworking of Baltic Shield sources. Chukotka, Wrangel Island and NW Alaska are similar and were once paleogeographically linked to the flanks of Baltica. Formation of the Urals in the Permian brought Siberia and Baltica together, bringing new orogenic sources to Baltica. Soon after, Permo

  8. Arctic Ocean

    Science.gov (United States)

    Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

    2000-01-01

    The Arctic Ocean is the smallest of the Earth's four major oceans, covering 14x10(exp 6) sq km located entirely within the Arctic Circle (66 deg 33 min N). It is a major player in the climate of the north polar region and has a variable sea ice cover that tends to increase its sensitivity to climate change. Its temperature, salinity, and ice cover have all undergone changes in the past several decades, although it is uncertain whether these predominantly reflect long-term trends, oscillations within the system, or natural variability. Major changes include a warming and expansion of the Atlantic layer, at depths of 200-900 m, a warming of the upper ocean in the Beaufort Sea, a considerable thinning (perhaps as high as 40%) of the sea ice cover, a lesser and uneven retreat of the ice cover (averaging approximately 3% per decade), and a mixed pattern of salinity increases and decreases.

  9. Arctic Shipping

    DEFF Research Database (Denmark)

    Hansen, Carsten Ørts; Grønsedt, Peter; Lindstrøm Graversen, Christian;

    maritime industries (including shipping, offshore energy, ports, and maritime service and equipment suppliers) as well as addresses topics that cut across maritime industries (regulation and competitiveness). The topics and narrower research questions addressed in the initiative were developed in close......, the latter aiming at developing key concepts and building up a basic industry knowledge base for further development of CBS Maritime research and teaching. This report attempts to map the opportunities and challenges for the maritime industry in an increasingly accessible Arctic Ocean...

  10. Controls on the composition and lability of dissolved organic matter in Siberia's Kolyma River basin

    Science.gov (United States)

    Mann, P. J.; Davydova, A.; Zimov, N.; Spencer, R. G. M.; Davydov, S.; Bulygina, E.; Zimov, S.; Holmes, R. M.

    2012-03-01

    High-latitude northern rivers export globally significant quantities of dissolved organic carbon (DOC) to the Arctic Ocean. Climate change, and its associated impacts on hydrology and potential mobilization of ancient organic matter from permafrost, is likely to modify the flux, composition, and thus biogeochemical cycling and fate of exported DOC in the Arctic. This study examined DOC concentration and the composition of dissolved organic matter (DOM) across the hydrograph in Siberia's Kolyma River, with a particular focus on the spring freshet period when the majority of the annual DOC load is exported. The composition of DOM within the Kolyma basin was characterized using absorbance-derived measurements (absorbance coefficienta330, specific UV absorbance (SUVA254), and spectral slope ratio SR) and fluorescence spectroscopy (fluorescence index and excitation-emission matrices (EEMs)), including parallel factor analyses of EEMs. Increased surface runoff during the spring freshet led to DOM optical properties indicative of terrestrial soil inputs with high humic-like fluorescence, SUVA254, and low SRand fluorescence index (FI). Under-ice waters, in contrast, displayed opposing trends in optical properties representing less aromatic, lower molecular weight DOM. We demonstrate that substantial losses of DOC can occur via biological (˜30% over 28 days) and photochemical pathways (>29% over 14 days), particularly in samples collected during the spring freshet. The emerging view is therefore that of a more dynamic and labile carbon pool than previously thought, where DOM composition plays a fundamental role in controlling the fate and removal of DOC at a pan-Arctic scale.

  11. Modelling CH4 emissions from arctic wetlands: effects of hydrological parameterization

    Directory of Open Access Journals (Sweden)

    P. M. Crill

    2007-09-01

    Full Text Available This study compares the CH4 fluxes from two arctic wetland sites of different annual temperatures during 2004 to 2006. The PEATLAND-VU model was used to simulate the emissions. The CH4 module of PEATLAND-VU is based on the Walter-Heimann model. The first site is located in northeast Siberia, Indigirka lowlands, Kytalyk reserve (70° N, 147° E in a continuous permafrost region with mean annual temperatures of –14.3°C. The other site is Stordalen mire in the eastern part of Lake Torneträsk (68° N, 19° E, ten kilometres east of Abisko, northern Sweden. It is located in a discontinuous permafrost region. Stordalen has a sub arctic climate with a mean annual temperature of –0.7°C. Model input consisted of observed temperature, precipitation and snow cover data. In all cases, modelled CH4 emissions show a direct correlation between variations in water table and soil temperature variations. The differences in CH4 emissions between the two sites are caused by different climate, hydrology, soil physical properties, vegetation type and NPP. For Kytalyk the simulated CH4 fluxes show similar trends during the growing season, having average values for 2004 to 2006 between 1.29–2.09 mg CH4 m−2 h−1. At Stordalen the simulated fluxes show a slightly lower average value for the same years (3.52 mg CH4 m−2 h−1 than the observed 4.7 mg CH4 m−2 h−1. The effect of the longer growing season at Stordalen is simulated correctly. Our study shows that modelling of arctic CH4 fluxes is improved by adding a relatively simple hydrological model that simulates the water table position from generic weather data. We conclude that CH4 fluxes at these sites are less sensitive to temperature variation than to water table variations. Furthermore, parameter uncertainty at site level in wetland CH4 process models is an important factor in large scale modelling of CH4 fluxes.

  12. Seasonal and interannual changes of hydrological regime of the Western Siberia

    Science.gov (United States)

    Zakharova, Elena; Kouraev, Alexei; Kolmakova, Maria; Bazanov, Vladimir; Skugarev, Andrei; Berezin, Alexander; Kirpotin, Sergei; Zemtsov, Valeriy; Biancamaria, Sylvain; Mognard, Nelly

    2010-05-01

    Western Siberia is a large region with mostly flat relief, that lead to the formation of a multitude of interconnected natural objects - large and small rivers streams, large floodplains, lakes, bogs etc. . Flooded areas and bogs also act as a buffer zone, providing a dampening "sponge" effect on the water redistribution within the river system. Large area covered by rivers and wetlands results in high rate of evaporation compared to any other large boreal watershed. Two contrasting processes are actually occurring in the Southern and Northern parts of the region. In the south, there is a progressive swamping which leads to forest death. In the north, there is a thermokarst activity or thawing permafrost in palsas of sub-arctic zone of Western Siberia. We present the results of systematization and classification of landscape patterns, as well as study of variability of hydrological processes in the study region at different temporal (from multi-year to seasonal) and spatial (from local to regional) scales through a multidisciplinary approach based on in situ and remote sensing data. Radar altimetry (TOPEX/Poseidon, Jason-1, GFO, ENVISAT), radiometry (SMMR, SSM/I) and optical data (Landsat) are used in combination with the in situ observations and the recent field studies done in 2008 and 2009. We present the variability of water level (from radar altimetry) and surface properties (from altimeter waveforms parameters) for the 21 mid-size watersheds of the Ob' river system and Nadym, Pur and Taz rivers. Seasonal and interannual variability of water abundance is studied using radar altimetry and radiometry. We analyse the role of the snow cover in the formation and seasonal distribution of runoff in the region of Poluy, Nadym, Pur and Taz rivers by using in situ and satellite estimates of the snow water equivalent. This research has been done in the framework of the Russian-French cooperation GDRI "CAR-WET-SIB", French ANR "IMPACT-Boreal" project and FP7 MONARCH

  13. Birch Stands Growth Increase in Western Siberia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Kuzmichev, Valeriy V.; Im, Sergey T.; Ranson, Kenneth J.

    2014-01-01

    Birch (Betula pendula Roth) growth within the Western Siberia forest-steppe was analyzed based on long-term (1897-2006) inventory data (height, diameter at breast height [dbh], and stand volume). Analysis of biometry parameters showed increased growth at the beginning of twenty-first century compared to similar stands (stands age = 40-60 years) at the end of nineteenth century. Mean height, dbh, and stem volume increased from 14 to 20 m, from 16 to 22 cm, and from approx. 63 to approx. 220 cu m/ha, respectively. Significant correlations were found between the stands mean height, dbh, and volume on the one hand, and vegetation period length (r(sub s) = 0.71 to 0.74), atmospheric CO2 concentration (r(sub s) = 0.71 to 0.76), and drought index (Standardized Precipitation-Evapotranspiration Index, r(sub s) = -0.33 to -0.51) on the other hand. The results obtained have revealed apparent climate-induced impacts (e.g. increase of vegetation period length and birch habitat drying due to drought increase) on the stands growth. Along with this, a high correlation of birch biometric parameters and [CO2] in ambient air indicated an effect of CO2 fertilization. Meanwhile, further drought increase may switch birch stand growth into decline and greater mortality as has already been observed within the Trans-Baikal forest-steppe ecotone.

  14. Climate-Driven Changes Within the Larch Forest of Northern Siberia

    Science.gov (United States)

    Kharuk, V.

    2015-12-01

    Thanks to the support of NASA's Carbon Cycle and Ecosystem Focus Area programs, joint NASA/ Siberian Branch of the Russian Academy of Sciences studies have been conducted throughout Siberia. The overall objective has been to obtain field and satellite measurements to examine carbon stocks and track changes in forests across this vast area. In this presentation, we discuss some of the finding from this 25+ year collaboration' i.e., observed climate-driven changes within larch communities in northern Siberia. Field measurements and satellite data, including Terra/MODIS, Landsat, GRACE and QuickBird were used for analysis of forest conditions. The following results will be discussed. (1). At the northern limit of larch (Larix gmelinii) range (i.e.,~72°N) tree mortality was observed during the cooling period from the 16th century to the beginning of the 19th century. Post- Little Ice Age (LIA) trees re-establishment followed warming temperatures by the middle of the19th century. The current tree line has recovered to the pre-LIA line location although tree heights and stand densities are comparatively lower. The mean rate of upward migration was found to be 0.35 m yr-1 (with a range of 0.21-0.58). (2) The migration of the "dark needle conifers" (DNC: Abies sibirica, Pinus sibirica, Picea obovata) into the southern margin zone of larch dominated forest was documented. Meanwhile, within the traditional DNC range decline and mortality of both Siberian pine and fir were observed and attributed, primarily, due to an increased drought. (3) Within Central Siberia larch growth is limited by early summer temperatures and available water from thawing permafrost. Larch tree ring width (TRW) correlated with early summer temperatures and water vapor pressure (r = 0.73 and r = 0.69, respectively), drought (SPEI; r = 0.68-0.82), snow accumulation (r = 0.61), previous year precipitation (r = 0.63) and soil water anomalies (r = 0.79). Larch TRW growth and Gross Primary Productivity

  15. Arctic Diatoms

    DEFF Research Database (Denmark)

    Tammilehto, Anna

    shellfish poisoning (ASP). This thesis showed that three most abundant mesozooplankton species (Calanus finmarchicus, C. glacialis and C. hyperboreus and copepodite stages C3 and C4) in the study area (Disko Bay, western Greenland) feed upon toxic P. seriata and retain the toxin, and may therefore act...... as vectors for DA to higher levels in the arctic marine food web, posing a possible risk also to humans. DA production in P. seriata was, for the first time, found to be induced by chemical cues from C. finmarchicus, C. hyperboreus and copepodite stages C3 and C4, suggesting that DA may be related to defense...

  16. 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

  17. Content and distribution of trace metals in pristine permafrost environments of Northeastern Siberia, Russia

    Science.gov (United States)

    Antcibor, I.; Eschenbach, A.; Kutzbach, L.; Bolshiyanov, D.; Pfeiffer, E.-M.

    2012-04-01

    Arctic regions are one of the most sensitive areas with respect to climatic changes and human impacts. Research is required to discover how the function of permafrost soils as a buffering system for metal pollutants could change in response to the predicted changes. The goal of this work is to determine the background levels of trace metals in the pristine arctic ecosystems of the Lena River Delta in Northeastern Siberia and to evaluate the possible effect of human impacts on this arctic region. The Lena River Delta represents areas with different dominating geomorphologic processes that can generally be divided between accumulation and erosion sites. Frequent changes of the river water level create different periods of sedimentation and result in the formation of stratified soils and sediment layers which are dominated either by mineral substrates with allochthonous organic matter or pure autochthonous peat. The deposited sediments that have formed the delta islands are mostly composed of sand fractions; therefore the buffering effects of clay materials can be neglected. Samoylov Island is representative of the south-central and eastern modern delta surfaces of the Lena River Delta and is selected as a pilot study site. We determined total element contents of Fe, Mn, Zn, Cd, Ni, Cu, As, Pb, Co and Hg in soil horizons from different polygonal elevated rims, polygonal depressed centers and the middle floodplain. High gravimetric concentrations (related to dry mass of soil material) of Mn and Fe are found within all soil profiles and vary from 0.14 to 1.39 g kg-1 and from 10.7 to 41.2 g kg-1, respectively. While the trace element concentrations do not exceed typical crustal abundances, the maximum values of most of the metals are observed within the soil profile situated at the middle floodplain. This finding suggests that apart from the parent material the second potential source of trace metals is due to allochthonous substance input during annual flooding of the

  18. Projections and predictability of Arctic shipping accessibility

    Science.gov (United States)

    Melia, Nathanael; Haines, Keith; Hawkins, Ed

    2016-04-01

    The observed reduction in Arctic sea ice opens up the potential for shorter shipping routes across the Arctic Ocean, leading to potentially significant global economic savings. We demonstrate, using bias-corrected global climate models, that the projected sea ice melt through the 21st century increases opportunities for ships to sail through the Arctic between North Atlantic and East Asian ports. Transit potential for Open Water vessels doubles from early to mid-century and coincides with the opening of the trans-polar sea route. Although seasonal, routes become more reliable with an overall increased shipping season length, but with considerable variability from year-to-year. We also demonstrate that there is potential predictability for whether a particular season will be relatively open or closed to shipping access from a few months ahead.

  19. Structure of the Crust and the Lithosperic Mantle in Siberia

    DEFF Research Database (Denmark)

    Cherepanova, Yulia

    the development of a new regional crustal model, SibCrust, that is a digital crustal model for both the Siberian Craton and the West Siberian Basin. The SibCrust model, constrained by digitizing of all available seismic profiles and crustal velocity models across the Siberia, also includes a critical quality...

  20. Trend and interannual variability of summer precipitation and the atmospheric water vapor convergence in the Arctic circumpolar region

    Science.gov (United States)

    Hiyama, T.; Fujinami, H.; Oshima, K.

    2014-12-01

    This study investigated trend and interannual variability of summer (June, July and August) precipitation and the atmospheric water vapor convergence in the Arctic circumpolar region, with an emphasis on recent increase of those around the Lena river basin in eastern Siberia. Data used in this study are an archived precipitation data (PREC/L) and atmospheric re-analysis data (JRA-25, JRA-55). Previous studies have revealed a negative correlation in the summer atmospheric circulation pattern between the Lena and Ob river basins. However little is known about the atmospheric water cycles in the Arctic circumpolar region, including the Mackenzie river basin. Hence we compared the trend and interannual variability of summer precipitation and the atmospheric water vapor convergence in three large North Eurasian river (Lena, Yenisei, and Ob) basins together with the Mackenzie basin. The analyzed results are as follows. 1) In the highest five-year summer precipitation in the Lena river basin during the period 1958 to 2012, the center of the cyclonic circulation shifted to the east, from the Kara and Barents Seas over the region across the Yenisei and Lena. In the years, significant cyclonic deviation was present. The deviation distribution of the height field and the atmospheric water vapor flux from the west to the Lena river basin were significantly increased, so as to form a positive deviation of summer precipitation. 2) Significant increases (positive trend) in the summer precipitation were detected from 1984 to 2011 in the Lena, Yenisei, and the Mackenzie river basins. However, summer precipitation showed significant decreases (negative trend) over Mongolia and Europe/Russia. This was because anticyclones dominated in these regions. 3) A significant enhancement of cyclonic circulation was detected from 2005 to 2008 on the Eurasian side of the Arctic Ocean. However, anticyclones appeared over Mongolia. These probably increased the atmospheric water vapor convergence

  1. Early to middle Pleistocene Arctic coastal ice caps in the Northern Interior Plains of Canada, a comparison with northeastern Siberian coastal uplands

    Science.gov (United States)

    Duk-Rodkin, A.; Barendregt, R. W.; Velichko, A. A.; Galloway, J. M.; McNeil, D.

    2012-12-01

    A stratigraphic record of four to five ice-cap developments during the last 2.6 myr was discovered along the Northern Interior Plains (NIP) of the Canadian Continental Arctic Coast below 500 m elevation. Paleomagnetism, macrofossils, foraminifera, till fabrics and pebble lithologies were obtained from outcrops. This glacial stratigraphic record is less extensive than that found west of the continental divide in the Northern Canadian Cordillera, where at least 11 glaciations occurred in the last 2.7 Ma and where uplift along the south side of NW North America during the Pliocene set the stage for large scale glaciations. These coastal mountains and the continental divide created a double rain shadow effect that limited Pacific moisture reaching the NIP. East of the continental divide, moisture supply was only sufficient to form valley glaciers in five of the glacial periods that affected the Cordillera. The NIP was also affected by five glaciations. Ice-caps developed periodically and in the late Pleistocene, the Laurentide Ice Sheet covered all of the NIP. During interglacial times, the NIP experienced dry steppe conditions, similar to modern northern climates found in regions of extreme continentality. The geographic setting along the eastern Siberian coast is comparable to conditions of the NIP, but no record of glaciations exists from upland areas near the Arctic Ocean. Moisture supply and temperature were likely insufficient to form local ice caps at low coastal elevations (rain shadow effect" formed by the Chersky, Suntar-Khayta, and Momsky ranges precluded moisture-bearing air originating from the Sea of Okhotsk to reach the Arctic Ocean. The absence of ice-caps here seems to indicate a frozen Arctic Ocean during most of the Pleistocene. Large scale glaciations (e.g., Cordilleran ice sheets) commenced in NW North America in the late Gauss Chron (Pacific Ocean influence), in Europe during the late Matuyama Chron (Atlantic Ocean influence), and in Siberia

  2. International Siberian Shelf Study 2008 (ISSS-08): The major IPY ship-based program along the entire Eurasian-Arctic continental shelf with combined biogeochemical and geophysical observations

    Science.gov (United States)

    Semiletov, I.; Gustaffson, O.; Dudarev, O.; Andersson, P.; Salyuk, A.; Andersson, L.; Shakhova, N.

    2008-12-01

    The coastal margin north of Eurasia is the world's largest continental shelf. It provides an important regime for transport and processing of heat, freshwater and carbon between its Siberian drainage basins and the high Arctic Ocean. There are gradients in climate and carbon dynamics along the Barents, Kara, Laptev, East Siberian, and Chuckchi Sea conduits. The continent-scale system is characterized by strong discharge through the Great Russian Arctic Rivers, onshore and offshore-subsea permafrost with massive shallow methane deposits, eroding carbon-rich coasts, and shelf-feeding of the Arctic halocline. The region is of particular interest from the perspective of carbon-climate couplings. Surface air temperature anomalies for 2000--2005 in the East Siberia are about 4°C higher than preceding 30-year average. Hence, there is a potential for remobilization of 'old' terrestrial carbon from thawing tundra permafrost and coastal-ice complexes as well as methane release from subsea permafrost. The role of climate warming on shelf-derived halocline waters has also yet to be elucidated. The 50-day Russia-Sweden-USA expedition onboard H/V Jacob Smirnitsky presented a golden opportunity to shed lights on these issues. A second ISSS-08 component investigated in detail the Lena river and the shallow Laptev Sea. The ISSS-08 had a particular geographical focus on the Laptev, East Siberian and Russian-sector of Chukchi Sea as this is the most enigmatic and under-sampled region in the Arctic ocean. A multitude of complementary studies were carried out. Underway sampling of 4 m seawater was continuously monitored for a broad range of geophysical and biogeochemical parameters; air was continuously sampled for CH4 stable isotopes, aerosols and met properties including air-sea CO2 and CH4 turbulent fluxes . Detailed stations for sediment, water, and air were occupied off the river mouths of Ob, Yenisey, Lena, Indigirka and Kolyma. Five polygons outside sites of intense coastal

  3. A Heroic Tale's Travel from Siberia to the Balto-Finnic Peoples

    Directory of Open Access Journals (Sweden)

    Kristi Salve

    2005-08-01

    Full Text Available The article concerns a fairy tale from A. Andreiev’s fairy-tale index, namely AA 967, which has greatly interested Russian researchers because of its connection with bylina. However, this story is not of East Slavic origin but has enetered the Russians’ repertoire as a substrate. The case is even more interesting since the same story is also known in far East Siberia, among the Paleoasiatic Kets and Samoyed Selkups. The Ket stories are vividly Siberian narratives of inter-tribal feud. The same applies to the story’s western distribution’s periphery - it has been told as a true story in Finland and P.-L. Rausmaa has indexed it as a historical legend. Finnish and Ket versions are similar, while Karelian, Vepsian and probably also the version spread to Russians from them has obtained fairy tale motifs. Undisputable is the common origin of all these stories: coinciding facts are too complex to assume random similarity. The article also discusses whether the narrative is hostile towards women.

  4. Radioactivity in the Arctic Seas. Report for the International Arctic Seas Assessment Project (IASAP)

    International Nuclear Information System (INIS)

    This report provides comprehensive information on environmental conditions in the Arctic Seas as required for the study of possible radiological consequences from dumped high level radioactive wastes in the Kara Sea. The report describes the oceanography of the regions, with emphasis on the Kara and Barents Seas, including the East Novaya Zemlya Fjords. The ecological description concentrates on biological production, marine food-weds and fisheries in the Arctic Seas. The report presents data on radionuclide concentrations in the Kara and Barents Seas and uses these data to estimate the inventories of radionuclides currently in the marine environment of the Kara and Barents Seas

  5. Contrasting radiation and soil heat fluxes in Arctic shrub and wet sedge tundra

    Science.gov (United States)

    Juszak, Inge; Eugster, Werner; Heijmans, Monique M. P. D.; Schaepman-Strub, Gabriela

    2016-07-01

    Vegetation changes, such as shrub encroachment and wetland expansion, have been observed in many Arctic tundra regions. These changes feed back to permafrost and climate. Permafrost can be protected by soil shading through vegetation as it reduces the amount of solar energy available for thawing. Regional climate can be affected by a reduction in surface albedo as more energy is available for atmospheric and soil heating. Here, we compared the shortwave radiation budget of two common Arctic tundra vegetation types dominated by dwarf shrubs (Betula nana) and wet sedges (Eriophorum angustifolium) in North-East Siberia. We measured time series of the shortwave and longwave radiation budget above the canopy and transmitted radiation below the canopy. Additionally, we quantified soil temperature and heat flux as well as active layer thickness. The mean growing season albedo of dwarf shrubs was 0.15 ± 0.01, for sedges it was higher (0.17 ± 0.02). Dwarf shrub transmittance was 0.36 ± 0.07 on average, and sedge transmittance was 0.28 ± 0.08. The standing dead leaves contributed strongly to the soil shading of wet sedges. Despite a lower albedo and less soil shading, the soil below dwarf shrubs conducted less heat resulting in a 17 cm shallower active layer as compared to sedges. This result was supported by additional, spatially distributed measurements of both vegetation types. Clouds were a major influencing factor for albedo and transmittance, particularly in sedge vegetation. Cloud cover reduced the albedo by 0.01 in dwarf shrubs and by 0.03 in sedges, while transmittance was increased by 0.08 and 0.10 in dwarf shrubs and sedges, respectively. Our results suggest that the observed deeper active layer below wet sedges is not primarily a result of the summer canopy radiation budget. Soil properties, such as soil albedo, moisture, and thermal conductivity, may be more influential, at least in our comparison between dwarf shrub vegetation on relatively dry patches and

  6. Arctic Landscape Within Reach

    Science.gov (United States)

    2008-01-01

    This image, one of the first captured by NASA's Phoenix Mars Lander, shows flat ground strewn with tiny pebbles and marked by small-scale polygonal cracking, a pattern seen widely in Martian high latitudes and also observed in permafrost terrains on Earth. The polygonal cracking is believed to have resulted from seasonal contraction and expansion of surface ice. Phoenix touched down on the Red Planet at 4:53 p.m. Pacific Time (7:53 p.m. Eastern Time), May 25, 2008, in an arctic region called Vastitas Borealis, at 68 degrees north latitude, 234 degrees east longitude. This image was acquired at the Phoenix landing site by the Surface Stereo Imager on day 1 of the mission on the surface of Mars, or Sol 0, after the May 25, 2008, landing. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  7. A Preliminary Study on the Relationship Between Arctic Oscillation and Daily SLP Variance in the Northern Hemisphere During Wintertime

    Institute of Scientific and Technical Information of China (English)

    GONG Daoyi; Helge DRANGE

    2005-01-01

    In the present study, the authors investigated the relationship between the Arctic Oscillation (AO) and the high-frequency variability of daily sea level pressures in the Northern Hemisphere in winter (November through March), using NCEP/NCAR reanalysis datasets for the time period of 1948/49-2000/01.High-frequency signals are defined as those with timescales shorter than three weeks and measured in terms of variance, for each winter for each grid. The correlations between monthly mean AO index and high-frequency variance are conducted. A predominant feature is that several regional centers with high correlation show up in the middle to high latitudes. Significant areas include mid- to high-latitude Asia centered at Siberia, northern Europe and the middle-latitude North Atlantic east of northern Africa. Their strong correlations can also be confirmed by the singular value decomposition analysis of covariance between mean SLP and high-frequency variance. This indicates that the relationship of AO with daily Sea Level Pressure (SLP) is confined to some specific regions in association with the inherent atmospheric dynamics. In middle-latitude Asia, there is a significant (at the 95% level) trend of variance of-2.26% (10yr)-1. Another region that displays a strong trend is the northwestern Pacific with a significant rate of change of 0.80% (10 yr)-1. If the winter of 1948/49, an apparent outlier, is excluded, a steady linear trend of +1.51% (10 yr)-1 shows up in northern Europe. The variance probability density functions (PDFs) are found to change in association with different AO phases. The changes corresponding to high and low AO phases, however, are asymmetric in these regions. Some regions such as northern Europe display much stronger changes in high AO years, whereas some other regions such as Siberia show a stronger connection to low AO conditions. These features are supported by ECMWF reanalysis data. However, the dynamical mechanisms involved in the AO

  8. Siberia on Russian mental maps: The imperial and national space

    Directory of Open Access Journals (Sweden)

    Subotić Milan

    2012-01-01

    Full Text Available Starting from the theoretical problem of understanding the nation-building process within continental empires, this paper investigates the various meanings of ‘Siberia’ in the Russian imperial and national imagination. Analyzing discursive practices that create various representations of the geographical space, this study shows the changes in Russian perceptions of Siberia from the ‘alien’ space and the ‘colony’, to an unalienable part of the national territory (‘Russian land’ or ‘homeland’. Tracing the creation of ‘Russianness’ of Siberia, the author interprets this concept as a part of broader debates about ‘Russian identity’ and the relationship between ‘European’ and ‘Asiatic’ Russia. Therefore, the principal aim of the present study is to examine one of the most important aspects of the process Russia’s transformation from imperial to a ‘nationalizing State’.

  9. Studies of Fire Nature in the Forests of Siberia

    Directory of Open Access Journals (Sweden)

    P. A. Tsvetkov

    2014-06-01

    Full Text Available An analytical review of forest fires in the forests of Siberia from literature data published over the past 50 years is given. Prior to 1970 the main attention in publications was given to the investigation of fire nature in the southern taiga and mountain forests of Western and Central Siberia, Altai and Trans-Baikal. From 1971 to 1980, publications were characterized by wider aspects of forest fire research and expansion of the geographical area of coverage. In the next 15–20 years, the main consideration was given to the impact of fires on forest formation process, fire emissions, carbon balance, and fire management’ problems. Also in this paper, the main trends and goals for future research are determined.

  10. Gravity Variation in Siberia: GRACE Observation and Possible Causes

    Directory of Open Access Journals (Sweden)

    Benjamin Fong Chao

    2011-01-01

    Full Text Available We report the finding, from the GRACE observation, of an increasing trend in the gravity anomaly in Siberia at the rate of up to 0.5 ugal yr-1 during 2003/1 - 2009/12, in the backdrop of a negative anomaly of magnitude on the order of ~-10 mgal. In consideration of the non-uniqueness of the gravitational inverse problem, we examine in some detail the various possible geophysical causes to explain the increasing gravity signal. We find two geophysical mechanisms being the most plausible, namely the melting of permafrost and the GIA post-glacial rebound. We conclude that these two mechanisms cannot be ruled out as causes for the regional gravity increase in Siberia, based on gravity data and in want of ancillary geophysical data in the region. More definitive identification of the contributions of the various causes awaits further studies.

  11. [Lactase deficiency among representatives of various nationalities of Siberia].

    Science.gov (United States)

    Zhvavyĭ, N F; Kozlov, A I; Kondik, V M

    1991-01-01

    Some features of lactase tolerance were investigated in representatives of varying groups of indigenous population in Siberia-Mansi, Khanty, Nenets, Buryats. The indirect method was used to evaluate lactase activity. A total of 92 subjects were investigated. It was found that 32% of the representatives of the Urals population group and 53% of Buryats were capable of lactase assimilating. The data obtained correspond to the cultural-genetic hypothesis on the nature of lactase tolerance in the representatives of different ethnic groups.

  12. Microbiological assessment of technogenicaly disturbed forest ecosystems in Central Siberia

    OpenAIRE

    A. V. Bogorodskaya

    2016-01-01

    The state of soil microbial complexes of forest ecosystems of Central Siberia, disturbed by cutting, fires, emissions of pollutants and mining was investigated. The most appropriate indicators for early diagnosis of the condition and sustainability assessment of soils were the contents of microbial biomass, the intensity of the basal respiration and microbial metabolic quotient. Recorded time quantitative and structural-taxonomic restructuring of ecological trophic groups of microorganisms ex...

  13. Forest cover disturbances in the South Taiga of West Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Dyukarev, E A; Pologova, N N; Golovatskaya, E A; Dyukarev, A G, E-mail: egor@imces.ru [Institute of Monitoring of Climatic and Ecological Systems SB RAS, Akademicheskii Prospekt 10/3 (Russian Federation)

    2011-07-15

    Analysis of vegetation cover and tendencies in forest cover changes at a typical site in the south of West Siberia was performed using remote sensing observations from Landsat. The Northern Eurasia Land Cover legend was used for the assessment of unsupervised classification results. The land cover maps constructed have shown that about half of the study area is occupied by wetlands with several distinctively different vegetation types. The area studied is typical for the South Taiga zone (ecoregion) of Western Siberia from the Ob' river to the Irtysh river, where loamy and clayey soil forming rocks are widespread. Similar vegetation structures dominate over 600 000 km{sup 2}, or about 20%, of the West Siberia area. Analyses of the forest cover changes show that the forest cover loss is not very significant. The area of forest disturbed in 1990-9 is equal to 16 008 ha. The area of forest disturbances during the 2000-7 period was about twice as high (30 907 ha). The main reasons for the forest reduction are intensive forest harvesting and strong windthrow. The high sustainability of the region studied against anthropogenic impacts is explained by the high overall wetness of the territory, the small population density, and the prevalence of deciduous forests at different succession stages with rich vegetation cover.

  14. Low Density of Top Predators (Seabirds and Marine Mammals in the High Arctic Pack Ice

    Directory of Open Access Journals (Sweden)

    Claude R. Joiris

    2016-01-01

    Full Text Available The at-sea distribution of top predators, seabirds and marine mammals, was determined in the high Arctic pack ice on board the icebreaker RV Polarstern in July to September 2014. In total, 1,620 transect counts were realised, lasting 30 min each. The five most numerous seabird species represented 74% of the total of 15,150 individuals registered: kittiwake Rissa tridactyla, fulmar Fulmarus glacialis, puffin Fratercula arctica, Ross’s gull Rhodostethia rosea, and little auk Alle alle. Eight cetacean species were tallied for a total of 330 individuals, mainly white-beaked dolphin Lagenorhynchus albirostris and fin whale Balaenoptera physalus. Five pinniped species were represented by a total of 55 individuals and the polar bear Ursus maritimus was represented by 12 individuals. Four main geographical zones were identified: from Tromsø to the outer marginal ice zone (OMIZ, the Arctic pack ice (close pack ice, CPI, the end of Lomonosov Ridge off Siberia, and the route off Siberia and northern Norway. Important differences were detected between zones, both in species composition and in individual abundance. Low numbers of species and high proportion of individuals for some of them can be considered to reflect very low biodiversity. Numbers encountered in zones 2 to 4 were very low in comparison with other European Arctic seas. The observed differences showed strong patterns.

  15. Observations of atmospheric methane concentrations and sources at two supersites Tiksi, northern Siberia and Pallas-Sodankylä, northern Finland (Invited)

    Science.gov (United States)

    Laurila, T. J.; Aurela, M.; Hatakka, J.; Aalto, T.; Lohila, A.; Asmi, E.; Kondratyev, V.; Ivakhov, V.; Reshetnikov, A.; Makshtas, A. P.; Dlugokencky, E. J.; Uttal, T.

    2013-12-01

    Arctic and Boreal regions are important in the global methane budget mainly because emissions are large from the extensive wetlands. Recently the potential for increased emissions from methane hydrates under sediments at the bottom of the Arctic Ocean has been recognized. Resource exploitation in the Arctic is expanding and includes gas and oil drilling. Together with climate warming, we may expect changes in methane emissions from high northern latitudes. The main tools to probe the effect of this development on atmospheric methane are atmospheric methane observations and local emission measurements by micrometeorological and chamber methods. To better understand emissions at small and large scales, so called supersites have been introduced. At these sites, both atmospheric concentrations and emissions from representative ecosystems, together with suite of other environmental information, are measured continuously. We are running two of these supersites: Pallas-Sodankylä in northern Finland and Tiksi in Siberia on the coast of the Laptev Sea. In spite of the fact that both sites are north of the Arctic Circle, environmental conditions differ very much. In northern Scandinavia, climate is relatively marine, and wetland methane emissions are active throughout the year. In continental Tiksi the active layer is 30-80 cm and methane emissions cease during the coldest months when soil temperature is close to -20°C. Air mass advection is either from continental Siberia or from the Siberian seas. Forest and tundra fires are relatively common. At Pallas, advection is from the forested boreal and industrialized areas of Europe or the Norwegian or Barents Sea. In this presentation, we show seasonal variations of atmospheric methane concentrations at World Meteorological Organization - Global Atmosphere Watch sites: Pallas-Sodankylä and Tiksi. Source areas have been analyzed by trajectories. The main sources of methane in Tiksi were wetlands and the Laptev Sea, which is

  16. 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...

  17. Using a Whole-stream Approach to Quantify Headwater Yedoma DOC Processing Rates in NE Siberia, Russia

    Science.gov (United States)

    Heslop, J.; Walter Anthony, K. M.; Davydova, A.; Davydov, S. P.; Zimov, N.

    2015-12-01

    Climate warming triggers the release of permafrost organic carbon (OC) via permafrost thaw and erosion, exporting large amounts of terrestrial C to aquatic environments and making previously frozen OC from a range of soil depths available for microbial processing. It is estimated 210-476 Pg C is stored in deep, ice-rich loess-dominated soils referred to as yedoma. Yedoma is extensive in NE Siberia and Alaska, where it underlies an area of over 1,000,000 km2 and averages 25 m in thickness. Recent research suggests ancient (Pleistocene-aged) permafrost OC, such as yedoma OC, is rapidly and preferentially utilized by microbial communities in Arctic headwater streams. We utilized a combination of short-term laboratory incubations and a whole-stream approach to examine permafrost-derived dissolved organic carbon (DOC) uptake, processing, and transport rates in a small stream which drains yedoma uplands in Cherskii, NE Siberia. Short-term incubations were conducted on permafrost leachates mixed with stream water to quantify microbial processing rates of permafrost-derived DOC from leachates made with surface (0-15 cm), shallow (70-100 cm), and deep (<2 m) yedoma sediments. In addition, we conducted whole-stream DOC release experiments to quantify permafrost DOC uptake length, rate, and velocity. DOC composition from samples collected during both the incubations and the nutrient-release experiments was characterized using absorbance measurements (SUVA254 and SR) and florescence spectrometry (EEMs) to quantify how DOC composition correlates to and changes with permafrost DOC bioavailability and processing parameters. Preliminary results suggest DOC processing rates may be highest in leachates made from surface sediments, which receive fresh OC input from modern ecosystems, and from deep sediments, which contain ancient, previously immobile OC. Shallow permafrost OC, which experiences degradation from annual freeze-thaw cycles without receiving fresh OC input, may have the

  18. Hydrochemical composition of thermokarst lake waters in the permafrost zone of western Siberia within the context of climate change

    Directory of Open Access Journals (Sweden)

    R. M. Manasypov

    2013-11-01

    Full Text Available This work describes the current state of thaw lake and pond ecosystems, the mechanisms of their formation and succession, which was assessed via field work during several summer campaigns, and the laboratory analysis of water samples that were collected in the northern part of western Siberia within continuous and discontinuous permafrost zones. We analyzed the elemental chemical composition of lake waters as a function of lake diameter, over more than two orders of magnitude of the lake size, and described the peculiarities of the elemental composition of the thermokarst water body ecosystem during various stages of lake development. We revealed significant correlations between Fe, Al and dissolved organic carbon (DOC and various chemical elements across a latitude gradient of approximately 900 km. Several groups of chemical elements were distinguished that reflect the dynamic succession of the studied area of water bodies. Combining the data of the studied latitude profile with the information available in the current literature demonstrated that the average dissolved elemental concentrations in lakes of different size ranges exhibit specific dependencies on the latitude position, which is presumably linked to (1 leaching of the elements from frozen peat, which is the main source of solutes in thermokarst lakes, (2 marine atmospheric aerosol depositions, notably at the proximity to the sea border, and (3 short-range industrial pollution of certain metals from the largest Russian arctic smelter. We discuss the evolution of thermokarst lake chemical compositions during their formation and drainage and foresee the consequences of climate warming and permafrost thaw on the hydrochemistry of the thaw lakes and ponds of western Siberia.

  19. 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.)

  20. The Arctic Ocean ice balance - A Kalman smoother estimate

    Science.gov (United States)

    Thomas, D. R.; Rothrock, D. A.

    1993-01-01

    The methodology of Kalman filtering and smoothing is used to integrate a 7-year time series of buoy-derived ice motion fields and satellite passive microwave observations. The result is a record of the concentrations of open water, first-year ice, and multiyear ice that we believe is better than the estimates based on the microwave data alone. The Kalman procedure interprets the evolution of the ice cover in terms of advection, melt, growth, ridging, and aging of first-year into multiyear ice. Generally, the regions along the coasts of Alaska and Siberia and the area just north of Fram Strait are sources of first-year ice, with the rest of the Arctic Ocean acting as a sink for first-year ice via ridging and aging. All the Arctic Ocean except for the Beaufort and Chukchi seas is a source of multiyear ice, with the Chukchi being the only internal multiyear ice sink. Export through Fram Strait is a major ice sink, but we find only about two-thirds the export and greater interannual variation than found in previous studies. There is no discernible trend in the area of multiyear ice in the Arctic Ocean during the 7 years.

  1. 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.

  2. Plant response to climate change along the forest-tundra ecotone in northeastern Siberia.

    Science.gov (United States)

    Berner, Logan T; Beck, Pieter S A; Bunn, Andrew G; Goetz, Scott J

    2013-11-01

    Russia's boreal (taiga) biome will likely contract sharply and shift northward in response to 21st century climatic change, yet few studies have examined plant response to climatic variability along the northern margin. We quantified climate dynamics, trends in plant growth, and growth-climate relationships across the tundra shrublands and Cajander larch (Larix cajanderi Mayr.) woodlands of the Kolyma river basin (657 000 km(2) ) in northeastern Siberia using satellite-derived normalized difference vegetation indices (NDVI), tree ring-width measurements, and climate data. Mean summer temperatures (Ts ) increased 1.0 °C from 1938 to 2009, though there was no trend (P > 0.05) in growing year precipitation or climate moisture index (CMIgy ). Mean summer NDVI (NDVIs ) increased significantly from 1982 to 2010 across 20% of the watershed, primarily in cold, shrub-dominated areas. NDVIs positively correlated (P watershed (r = 0.52 ± 0.09, mean ± SD), principally in cold areas, and with CMIgy across 9% of the watershed (r = 0.45 ± 0.06), largely in warm areas. Larch ring-width measurements from nine sites revealed that year-to-year (i.e., high-frequency) variation in growth positively correlated (P  0.05), which significantly correlated with NDVIs (r = 0.44, P < 0.05, 1982-2007). Both satellite and tree-ring analyses indicated that plant growth was constrained by both low temperatures and limited moisture availability and, furthermore, that warming enhanced growth. Impacts of future climatic change on forests near treeline in Arctic Russia will likely be influenced by shifts in both temperature and moisture, which implies that projections of future forest distribution and productivity in this area should take into account the interactions of energy and moisture limitations. PMID:23813896

  3. Changes in Microbial Nitrogen Dynamics with Soil Depth, and along a Latitudinal Transect in Western Siberia

    Science.gov (United States)

    Wild, B.; Schnecker, J.; Knoltsch, A.; Takriti, M.; Mooshammer, M.; Gentsch, N.; Mikutta, R.; Alves, R.; Gittel, A.; Lashchinskiy, N.; Richter, A.

    2015-12-01

    Plant productivity is often limited by low N availability, and this has been attributed to the slow breakdown of N-containing polymers such as proteins into amino acids that are small enough for uptake. Under such conditions, plants and microorganisms efficiently use the available N for growth, and the microbial release of excess N as ammonium (N mineralization), as well as the transformation of ammonium into nitrate (nitrification) is low. Nitrogen limitation is expected to increase towards high latitudes as conditions become less favourable for decomposition. On the other hand, within an ecosystem, microbial N limitation is expected to decrease with soil depth, following the decrease in the C/N ratio of organic matter. To test these hypotheses, we sampled organic topsoils, mineral topsoils and mineral subsoils from seven ecosystems along a latitudinal transect in Western Siberia, ranging from tundra (67°N) to boreal forest and further to steppe (54°N), and determined gross rates of protein depolymerization, N mineralization and nitrification using 15N pool dilution assays. We found that all rates decreased with depth following the decrease in organic matter content. Related to microbial biomass, however, only protein depolymerization decreased with depth, whereas N mineralization and nitrification significantly increased. This pattern was consistent across the seven ecosystems studied. Furthermore, we did not find indications for a decrease in microbial N limitation from arctic to temperate systems. Our findings thus challenge the perception of ubiquitous N limitation at high latitudes, but suggest a transition from N to C limitation of microorganisms with soil depth. With microbial N immobilization constrained by low C availability, subsoils might harbour an easily available N pool that can contribute to plant N nutrition, but might also promote N losses from the ecosystem, e.g., by nitrate leaching, even in high latitude systems such as tundra and boreal

  4. Episodes of cross-polar transport in the Arctic troposphere during July 2008 as seen from models, satellite, and aircraft observations

    Directory of Open Access Journals (Sweden)

    H. Sodemann

    2011-04-01

    Full Text Available During the POLARCAT summer campaign in 2008, two episodes (2–5 July and 7–10 July 2008 occurred where low-pressure systems traveled from Siberia across the Arctic Ocean towards the North Pole. The two cyclones had extensive smoke plumes from Siberian forest fires and anthropogenic sources in East Asia embedded in their associated air masses, creating an excellent opportunity to use satellite and aircraft observations to validate the performance of atmospheric transport models in the Arctic, which is a challenging model domain due to numerical and other complications.

    Here we compare transport simulations of carbon monoxide (CO from the Lagrangian transport model FLEXPART and the Eulerian chemical transport model TOMCAT with retrievals of total column CO from the IASI passive infrared sensor onboard the MetOp-A satellite. The main aspect of the comparison is how realistic horizontal and vertical structures are represented in the model simulations. Analysis of CALIPSO lidar curtains and in situ aircraft measurements provide further independent reference points to assess how reliable the model simulations are and what the main limitations are.

    The horizontal structure of mid-latitude pollution plumes agrees well between the IASI total column CO and the model simulations. However, finer-scale structures are too quickly diffused in the Eulerian model. Applying the IASI averaging kernels to the model data is essential for a meaningful comparison. Using aircraft data as a reference suggests that the satellite data are biased high, while TOMCAT is biased low. FLEXPART fits the aircraft data rather well, but due to added background concentrations the simulation is not independent from observations. The multi-data, multi-model approach allows separating the influences of meteorological fields, model realisation, and grid type on the plume structure. In addition to the very good agreement between simulated and observed total column CO

  5. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    Directory of Open Access Journals (Sweden)

    Q. T. Nguyen

    2013-01-01

    Full Text Available In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81° 36' N, 16° 40' W in North East Greenland were evaluated for a two-year period from March 2008 to February 2010. Source apportionment using Positive Matrix Factorization (PMF and COnstrained Physical REceptor Model (COPREM was based on measurements of black carbon, elements (Al, Si, S, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Zr, Pb and inorganic ions (SO2, SO42−, Na+, NH4+, NO3, Cl2−. In general, source apportionment results by PMF and COPREM showed good agreement. Five sources adequately explained the measurements, which included a Marine and a Soil source of natural origin and three additional anthropogenic sources, which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT model suggested a Canadian Arctic origin, despite certain influences from Southern and Eastern origins. Another anthropogenic source was characterised by high concentrations of Pb and As, which has been historically referred to as a Combustion source at Station Nord. The impacts of large-scale industry in Siberia, Russia were evident through high Cu concentrations in both the Combustion source and an additional Cu/Ni source.

    Br correlated well with the anthropogenic species S and Pb though the elements are unlikely to have a common origin. More likely, sulphuric acid aerosols serve as transport containers for Br species of marine origin. Of particular relevance to climate, sources of black carbon were identified to be

  6. Future vegetation-climate interactions in Eastern Siberia: an assessment of the competing effects of CO2 and secondary organic aerosols

    Science.gov (United States)

    Arneth, Almut; Makkonen, Risto; Olin, Stefan; Paasonen, Pauli; Holst, Thomas; Kajos, Maija K.; Kulmala, Markku; Maximov, Trofim; Miller, Paul A.; Schurgers, Guy

    2016-04-01

    Disproportional warming in the northern high latitudes and large carbon stocks in boreal and (sub)arctic ecosystems have raised concerns as to whether substantial positive climate feedbacks from biogeochemical process responses should be expected. Such feedbacks occur when increasing temperatures lead, for example, to a net release of CO2 or CH4. However, temperature-enhanced emissions of biogenic volatile organic compounds (BVOCs) have been shown to contribute to the growth of secondary organic aerosol (SOA), which is known to have a negative radiative climate effect. Combining measurements in Eastern Siberia with model-based estimates of vegetation and permafrost dynamics, BVOC emissions, and aerosol growth, we assess here possible future changes in ecosystem CO2 balance and BVOC-SOA interactions and discuss these changes in terms of possible climate effects. Globally, the effects of changes in Siberian ecosystem CO2 balance and SOA formation are small, but when concentrating on Siberia and the Northern Hemisphere the negative forcing from changed aerosol direct and indirect effects become notable - even though the associated temperature response would not necessarily follow a similar spatial pattern. While our analysis does not include other important processes that are of relevance for the climate system, the CO2 and BVOC-SOA interplay serves as an example for the complexity of the interactions between emissions and vegetation dynamics that underlie individual terrestrial processes and highlights the importance of addressing ecosystem-climate feedbacks in consistent, process-based model frameworks.

  7. Volcanoes and ENSO in millennium simulations: global impacts and regional reconstructions in East Asia

    Science.gov (United States)

    Zhang, Dan; Blender, Richard; Fraedrich, Klaus

    2013-02-01

    The impacts and cooperative effects of volcanic eruptions and ENSO (El Niño/Southern Oscillation) are analyzed in a millennium simulation for 800-2005 AD using the earth system model (ESM) ECHAM5/MPIOM/JSBACH subject to anthropogenic and natural forcings. The simulation comprises two ensembles, a first with weak (E1, five members) and a second with strong (E2, three members) variability total solar irradiance. In the analysis, the 21 most intense eruptions are selected in each ensemble member. Volcanoes with neutral ENSO states during two preceding winters cause a global cooling in the year after eruptions up to -2.5°C. The nonsignificant positive values in the tropical Pacific Ocean indicate an El Niño-like warming. In the winter after an eruption, warming is mainly found in the Arctic Ocean and the Bering Sea in E2 warming extends to Siberia and central Asia. The recovery times for the volcano-induced cooling (average for 31 eruptions) vary globally between 1 and 12 years. There is no significant increase of El Niño events after volcanic eruptions in both ensembles. The simulated temperature and the drought indices are compared with corresponding reconstructions in East Asia. Volcanoes cause a dramatic cooling in west China (-2°C) and a drought in East China during the year after the eruption. The reconstructions show similar cooling patterns with smaller magnitudes and confirm the dryness in East China. Without volcanoes, El Niño events reduce summer precipitation in the North, while South China becomes wetter; La Niña events cause opposite effects. El Niño events in the winters after eruptions compensate the cooling caused by volcanoes in most regions of China (consistent with reconstructions), while La Niña events intensify the cooling (up to -2.5°C). The simulated and reconstructed drought indices show tripole patterns which are altered by El Niño events. The simulated impact of the Tambora eruption in 1815, which caused the "year without summer

  8. Arctic Sea Level Reconstruction

    DEFF Research Database (Denmark)

    Svendsen, Peter Limkilde

    method.For oceanographic purposes, the altimetric record over the Arctic Ocean is inferiorin quality to that of moderate latitudes, but nonetheless an invaluable set of observations. During this project, newly processed Arctic altimetry from the ERS-1/-2 and Envisat missions has become available......Reconstruction of historical Arctic sea level is very difficult due to the limited coverage and quality of tide gauge and altimetry data in the area. This thesis addresses many of these issues, and discusses strategies to help achieve a stable and plausible reconstruction of Arctic sea level from...... 1950 to today.The primary record of historical sea level, on the order of several decades to a few centuries, is tide gauges. Tide gauge records from around the world are collected in the Permanent Service for Mean Sea Level (PSMSL) database, and includes data along the Arctic coasts. A reasonable...

  9. Ice-Free Arctic Ocean?

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years, according to a new report. The melting is accelerating, and researchers were unable to identify any natural processes that might slow the deicing of the Arctic. "What really makes the Arctic different from…

  10. Ocean surface waves in an ice-free Arctic Ocean

    Science.gov (United States)

    Li, Jian-Guo

    2016-08-01

    The retreat of the Arctic ice edge implies that global ocean surface wave models have to be extended at high latitudes or even to cover the North Pole in the future. The obstacles for conventional latitude-longitude grid wave models to cover the whole Arctic are the polar problems associated with their Eulerian advection schemes, including the Courant-Friedrichs-Lewy (CFL) restriction on diminishing grid length towards the Pole, the singularity at the Pole and the invalid scalar assumption for vector components defined relative to the local east direction. A spherical multiple-cell (SMC) grid is designed to solve these problems. It relaxes the CFL restriction by merging the longitudinal cells towards the Poles. A round polar cell is used to remove the singularity of the differential equation at the Pole. A fixed reference direction is introduced to define vector components within a limited Arctic part in mitigation of the scalar assumption errors at high latitudes. The SMC grid has been implemented in the WAVEWATCH III model and validated with altimeter and buoy observations, except for the Arctic part, which could not be fully tested due to a lack of observations as the polar region is still covered by sea ice. Here, an idealised ice-free Arctic case is used to test the Arctic part and it is compared with a reference case with real ice coverage. The comparison indicates that swell wave energy will increase near the ice-free Arctic coastlines due to increased fetch. An expanded Arctic part is used for comparisons of the Arctic part with available satellite measurements. It also provides a direct model comparison between the two reference systems in their overlapping zone.

  11. Global Change and Regional Landscape Response and Desertification in Siberia

    Institute of Scientific and Technical Information of China (English)

    V.M. PLYUSNIN; L.V. DANKO

    2011-01-01

    Climate changes and associated natural and anthropogenic processes have manifested themselves particularly clearly during the last two decades.The study of consequences of these changes has become one of the central scientific,social and political issues of our time (Pilot 2000;UNEP 2007).The study of the regional response of landscapes of Siberia to global changes is one of the fundamental tasks,aimed at ensuring the sustainable development of Siberian regions both at present time and in the future.Because in the 21 st century we should expect strong changes the humidity regime,accompanying the global warming (CCD 1994).

  12. A new model of crustal structure of Siberia

    DEFF Research Database (Denmark)

    Cherepanova, Yulia; Artemieva, Irina; Thybo, Hans

    2010-01-01

    We report a new model of the structure of the crust in Siberia that encompasses two large tectonic regions, the Paleozoic West Siberian Basin and the Precambrian Siberian craton. The area of study covers a significant part of the north Eurasia and extends from the Ural mountains in the west......) is the largest in the Paleoproterozoic and Mesoproterozoic regions of the Siberian Craton. A block with an unusually thick crust (47-58 km), bounded by the regions of thinned crust, extends in the longitudinal direction across the Siberian craton and cuts major tectonic boundaries which have sublatitudinal...

  13. 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.

  14. Continuous measurements of methane from a tower network over Siberia

    International Nuclear Information System (INIS)

    We have been conducting continuous measurements of Methane (CH4) concentration from an expanding network of towers (JR-STATION: Japan-Russia Siberian Tall Tower Inland Observation Network) located in taiga, steppe and wetland biomes of Siberia since 2004. High daytime means (>2000 ppb) observed simultaneously at several towers during winter, together with in situ weather data and NCEP/NCAR reanalysis data, indicate that high pressure systems caused CH4 accumulation at subcontinental scale due to the widespread formation of an inversion layer. Daytime means sometimes exceeded 2000 ppb, particularly in the summer of 2007 when temperature and precipitation rates were anomalously high over West Siberia, which implies that CH4 emission from wetlands were exceptionally high in 2007. Many hot spots detected by MODIS in the summer of 2007 illustrate that the contribution of biomass burning also cannot be neglected. Daytime mean CH4 concentrations from the Siberian tower sites were generally higher than CH4 values reported at NOAA coastal sites in the same latitudinal zone, and the difference in concentrations between two sets of sites was reproduced with a coupled Eulerian-Lagrangian transport model. Simulations of emissions from different CH4 sources suggested that the major contributor to variation switched from wetlands during summer to fossil fuel during winter.

  15. Rock-magnetic investigation of Siberia loess and its implication

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Multiple-rock magnetic investigations conducted on the loess-paleosol sequences at Kurtak in Southwestern Siberia reveal that the mass-normalized low-field magnetic susceptibility profiles reflect changes in lithology between relatively unweathered primary loess of glacial periods and the interglacial paleosols. Maxima in susceptibility values correspond with the least-weathered loess horizons, and minima with the humic horizons of soils. Frequency-dependent susceptibility of the loess-paleosol sequences at Kurtak is very low and practically uniform, indicating the dominance of non-SP ferrimagnetic minerals and negligible pedogenesis. The history of tempera- ture-dependence of susceptibility (TDS) and stepwise acquisition of the isothermal remanent magnetization (SIRM) have confirmed that magnetite is predominant magnetic mineral, and only few maghemite and probably hematite are present within the studied section. Anisotropy of the magnetic susceptibility (AMS) can be used to monitor tilt and disturbance of the sedimentary layers, and also to provide information about the paleo-transport direction for Siberia loess.

  16. Continuous measurements of methane from a tower network over Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Sasakawa, M.; Machida, T.; Saeki, T.; Koyama, Y.; Maksyutov, S. (Center for Global Environmental Research, National Inst. for Environmental Studies, Tsukuba, Ibaraki (Japan)); Shimoyama, K. (Inst. of Low Temperature Science, Hokkaido Univ., Hokkaido (Japan)); Tsuda, N. (Global Environmental Forum, Tokyo (Japan)); Suto, H. (Japan Aerospace Exploration Agency (Japan)); Arshinov, M.; Davydov, D.; Fofonov, A.; Krasnov, O. (Inst. of Atmospheric Optics, Russian Academy of Sciences, Siberian Branch (Russian Federation))

    2010-11-15

    We have been conducting continuous measurements of Methane (CH{sub 4}) concentration from an expanding network of towers (JR-STATION: Japan-Russia Siberian Tall Tower Inland Observation Network) located in taiga, steppe and wetland biomes of Siberia since 2004. High daytime means (>2000 ppb) observed simultaneously at several towers during winter, together with in situ weather data and NCEP/NCAR reanalysis data, indicate that high pressure systems caused CH{sub 4} accumulation at subcontinental scale due to the widespread formation of an inversion layer. Daytime means sometimes exceeded 2000 ppb, particularly in the summer of 2007 when temperature and precipitation rates were anomalously high over West Siberia, which implies that CH{sub 4} emission from wetlands were exceptionally high in 2007. Many hot spots detected by MODIS in the summer of 2007 illustrate that the contribution of biomass burning also cannot be neglected. Daytime mean CH{sub 4} concentrations from the Siberian tower sites were generally higher than CH{sub 4} values reported at NOAA coastal sites in the same latitudinal zone, and the difference in concentrations between two sets of sites was reproduced with a coupled Eulerian-Lagrangian transport model. Simulations of emissions from different CH{sub 4} sources suggested that the major contributor to variation switched from wetlands during summer to fossil fuel during winter.

  17. Technogenic forests on the disturbed lands of Western Siberia

    Directory of Open Access Journals (Sweden)

    V. N. Sedykh

    2016-04-01

    Full Text Available State of forest stands, which were originated naturally on mechanically disturbed moor-forestry lands near oil and gas complexes of Surgut Poles’e (Western Siberia is estimated in the paper. The differences of their timber value from natural stands are also discussed. Newly originated forests on the higher relief technogenic positions differ significantly from natural stands not only by their productivity, but also by their structure and biological diversity. It gives full possibility to call them technogenic forests. ft was unexpected, but the raised role of such forests opened potential productive forces of the Surgut Poles’e. This role showed a necessity of cardinal revision of forestry principles and natural protection of moor-forestry ecosystems. The state of compound technogenic forests witness positive consequences of the destruction of soil cover and significantly surpass the soil damage. Due to this fact, it is necessary to study deeply this phenomenon. The new data concerning this phenomenon will be a scientific development for creation a new normative base for rational natural use and re-cultivation of disturbed forestry parts of Western Siberia.

  18. 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 ...

  19. Ice-rich Permafrost and thermal denudation in the Batagay area (Yana Upland, East Siberia)

    OpenAIRE

    Kunitsky, V. V.; Syromyatnikov, Igor; Schirrmeister, Lutz; Skachov, Yu.B.; Grosse, GUido; Wetterich, Sebastian; M. N. Grigoriev

    2013-01-01

    Ice-rich permafrost in the Yana Upland has been investigated. The composition and structure of the permafrost has been determined. Their role in thermal denudation processes has been examined. The response of the ice-rich permafrost to recent climate change has been assessed.

  20. On Pliocaenicus costatus (Bacillariophyceae) in Lake El'gygytgyn, East Siberia

    NARCIS (Netherlands)

    Cremer, H.; Vijver, B. van de

    2006-01-01

    Pliocaenicus is a small, mainly fossil diatom genus that only rarely occurs in modern freshwater environments in eastern Russia. The only extant taxon of this genus, Pliocaenicus costatus , was studied from phytoplankton samples collected in Lake El'gygytgyn, a deep, ultraoligotrophic and low-conduc

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. Phytoplankton community structure in the Lena Delta (Siberia, Russia in relation to hydrography

    Directory of Open Access Journals (Sweden)

    A. C. Kraberg

    2013-02-01

    Full Text Available The Lena Delta in Northern Siberia is one of the largest river deltas in the world. During peak discharge, after the ice melt in spring, it delivers between 60–8000 m3s−1 of water and sediment into the Arctic Ocean. The Lena Delta and the Laptev Sea coast also constitute a~continuous permafrost region. Ongoing climate change, which is particularly pronounced in the Arctic, is leading to increased rates of permafrost thaw. This is likely to profoundly change the discharge rates of the Lena River and the chemistry of the river waters which are discharged into the coastal Laptev Sea, e.g. by increasing concentrations of inorganic nutrients, DOC and importantly methane. These physical and chemical changes will also affect the composition of and interactions between phytoplankton and zooplankton communities, forming the basis of the food web. However, before potential consequences of climate change for coastal arctic plankton communities can be judged, the inherent status of the diversity and linked foodweb interactions within the delta need to be established. As part of the AWI Lena Delta Programme in 2010 the phyto- and microzooplankton community in three river channels as well as four coastal transects were investigated to capture the typical river phytoplankton communities and the transitional zone of brackish/marine conditions. Most CTD profiles from 23 coastal stations showed very strong stratification. The only exception to this was a small a shallow and mixed area running from the outflow of Bykovskaya channel in a northerly direction parallel to the shore (transect 3. Of the five stations in this area three had a salinity of close to zero. Two further stations had salinities of around 2 and 5 throughout the water column. In the remaining transects on the other hand salinities varied between 5–30 with depth. Phytoplankton counts from the outflow from the Lena were dominated by diatoms (Aulacoseira species

  6. Remobilization and degradation of Muostakh Island (Laptev Sea) as part of the collapsing Arctic coastal ice complex

    Science.gov (United States)

    Sánchez-García, L.; Vonk, J.; Charkin, A.; Kosmach, D.; Dudarev, O.; Semiletov, I.; Gustafsson, Ö.

    2010-05-01

    East Siberiańs permafrost is thought to contain about 400 GtC (Giga = 109) [1] in form of the so-called Yedoma or Ice Complex, a huge stock of carbon mainly as frozen loess deposits formed during the Last Glacial Maximum (~40,000 years ago). The Pleistocene Ice Complex has not undergone much alteration by soil microorganisms since deposited, which makes it particularly sensitive to global warming effects on large-scale C dynamics. Accelerated coastal erosion of the Ice Complexes is brought on by a combination of thermal collapse, sea-level rise and enhanced wave fetch from loss of coastal sea-ice cover [2, 3]. Despite coastal erosion is estimated to deliver as much OC to the East Siberian Arctic Shelf (ESAS) as all the great Russian-Arctic rivers combined [3], the process is poorly understood, in particular with regard to the fate of the OM derived from coastal erosion. This study aims to alleviate the lack of information on the remobilization of OM from massive coastal erosion in the ESAS. The erosion evolution of a significant example of this destructive geological process (Muostakh Island, SE Laptev Sea), has been observed over the past decade and it has been estimated a retreat rate up to 20 m during the summer months (from 2001 to 2009). In summer 2006, soil samples were collected from Muostakh at 11 different locations along four 'erosion transects', spanning reliefs with ranges of approximately 25 m from the top plateau to the water boundary. On-site CO2measurements were carried out on the surface along five different transects across the island. Quantification of the organic carbon (OC), bulk 14C content and biomarker analysis (n-alkanes, n-alkanoic acids, n-alkanols, sterols) were performed to elucidate whether the old carbon forms eroded from Muostakh Island are subject to degradation. Elemental and isotopic analyses showed a vertical trend of younger (~modern) and C-enriched (OC~38%) material toward the plateau of the island, in contrast to the older

  7. Evaluation of Arctic Sea Ice Thickness Simulated by Arctic Ocean Model Intercomparison Project Models

    Science.gov (United States)

    Johnson, Mark; Proshuntinsky, Andrew; Aksenov, Yevgeny; Nguyen, An T.; Lindsay, Ron; Haas, Christian; Zhang, Jinlun; Diansky, Nikolay; Kwok, Ron; Maslowski, Wieslaw; Hakkinen, Sirpa; Ashik, Igor; De Cuevas, Beverly

    2012-01-01

    Six Arctic Ocean Model Intercomparison Project model simulations are compared with estimates of sea ice thickness derived from pan-Arctic satellite freeboard measurements (2004-2008); airborne electromagnetic measurements (2001-2009); ice draft data from moored instruments in Fram Strait, the Greenland Sea, and the Beaufort Sea (1992-2008) and from submarines (1975-2000); and drill hole data from the Arctic basin, Laptev, and East Siberian marginal seas (1982-1986) and coastal stations (1998-2009). Despite an assessment of six models that differ in numerical methods, resolution, domain, forcing, and boundary conditions, the models generally overestimate the thickness of measured ice thinner than approximately 2 mand underestimate the thickness of ice measured thicker than about approximately 2m. In the regions of flat immobile landfast ice (shallow Siberian Seas with depths less than 25-30 m), the models generally overestimate both the total observed sea ice thickness and rates of September and October ice growth from observations by more than 4 times and more than one standard deviation, respectively. The models do not reproduce conditions of fast ice formation and growth. Instead, the modeled fast ice is replaced with pack ice which drifts, generating ridges of increasing ice thickness, in addition to thermodynamic ice growth. Considering all observational data sets, the better correlations and smaller differences from observations are from the Estimating the Circulation and Climate of the Ocean, Phase II and Pan-Arctic Ice Ocean Modeling and Assimilation System models.

  8. Contradicting climate versus vegetation history in NE-Siberia?

    Science.gov (United States)

    Zech, M.; Zech, R.

    2009-04-01

    Northern Siberia may play a key role for the climate on the entire Earth. The classical Milankovitch Theory suggests that changes in summer insolation due to the Earth' orbital parameters caused build-up of snow and ice over the extensive continental masses at high northern latitudes. Various positive feedback mechanisms, like surface albedo and sequestration/release of atmospheric carbon dioxide in/from frozen, organic-rich soils, could then be responsible for the onset of global glaciations. More recently, high northern latitudes have also gained a lot of attention due to the potential of their soils and peats to release large amounts of methane and carbon dioxide. The Siberian ecosystems may turn into significant greenhouse gas sources as global warming continues and causes melting of permafrost and mineralisation of soil organic material that has been built up and stored over thousands of years. Quaternary scientists are therefore searching for long-term and continuous archives in order to reconstruct the Siberian climate and landscape history. A wide range of different analytical tools (e.g. different dating techniques, elemental composition, mineralogy, magnetic properties, grain size distribution, characterisation of organic matter and palynology) is used to infer palaeoclimatically and palaeoecologically relevant information. All of these methods have their advantages and their disadvantages. For instance, pollen analyses allow a high taxonomic differentiation, but variable pollination rates of different plant species, influx of long-distance transported pollen, and variable preservation of different pollen taxa have to be considered. Concerning the interpretation of pollen spectra in NE-Siberia, arboreal pollen, especially larch pollen, are traditionally considered to be ‘warm plant taxa', hence the occurrence of these pollen in archives is interpreted as reflecting warm interglacial or interstadial conditions. We have recently presented a multi

  9. 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.

  10. 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.

  11. Similarity in turbulent mixing and dissipation for scalars measured in Arctic at the Tiksi observatory

    Science.gov (United States)

    Grachev, Andrey; Uttal, Taneil; Konopleva-Akish, Elena; Persson, Ola; Fairall, Chris; Crepinsek, Sara; Albee, Robert; Makshtas, Alexander; Repina, Irina

    2015-04-01

    Measurements of atmospheric turbulence made at the Tiksi observatory located in the Russian East Siberia near the coast of the Arctic Ocean are used to study turbulent fluxes, scaling laws for turbulent mixing, dissipation rates, structure parameters, and correlation coefficients of various scalars (temperature, water vapor, and carbon dioxide). Turbulent fluxes along with other turbulent statistics and mean meteorological data were measured continuously throughout the year and reported hourly at various levels on the 20-m flux tower. According to our data collected during 2012-2014, strong upward sensible and latent heat fluxes are observed throughout the summer months indicating unstable stratification on average. During the Polar winter and cold seasons when the air temperature falls below freezing, the near-surface environment is generally stably stratified (downward sensible but upward latent heat fluxes). It is found that observed temporal variability of the carbon dioxide vertical flux was generally in phase with Monin-Obukhov stability parameter, z/L (L is the Obukhov length scale). On average the turbulent flux of carbon dioxide was mostly negative (uptake by the surface) for z/L < 0 and vice versa. Our study also analyzes the Bowen ratio and the similarity between the turbulent mixing of sensible heat, water vapor (latent heat), and carbon dioxide with a specific focus on the difference between different similarity functions including the dissipation rates. It has been traditionally assumed that turbulence transports scalars (e.g., water vapor, carbon dioxide, methane) similarly to temperature. The Tiksi data show that the water vapor and carbon dioxide are transported similarly (i.e. in the same "way" and with the same efficiency) to one another. However both water vapor and carbon dioxide fluxes are transported differently (but not substantially) as compared with the heat flux. The work is supported by the NOAA Climate Program Office, the U.S. National

  12. Earthquake-triggered liquefaction in Southern Siberia and surroundings: a base for predictive models and seismic hazard estimation

    Science.gov (United States)

    Lunina, Oksana

    2016-04-01

    The forms and location patterns of soil liquefaction induced by earthquakes in southern Siberia, Mongolia, and northern Kazakhstan in 1950 through 2014 have been investigated, using field methods and a database of coseismic effects created as a GIS MapInfo application, with a handy input box for large data arrays. Statistical analysis of the data has revealed regional relationships between the magnitude (Ms) of an earthquake and the maximum distance of its environmental effect to the epicenter and to the causative fault (Lunina et al., 2014). Estimated limit distances to the fault for the Ms = 8.1 largest event are 130 km that is 3.5 times as short as those to the epicenter, which is 450 km. Along with this the wider of the fault the less liquefaction cases happen. 93% of them are within 40 km from the causative fault. Analysis of liquefaction locations relative to nearest faults in southern East Siberia shows the distances to be within 8 km but 69% of all cases are within 1 km. As a result, predictive models have been created for locations of seismic liquefaction, assuming a fault pattern for some parts of the Baikal rift zone. Base on our field and world data, equations have been suggested to relate the maximum sizes of liquefaction-induced clastic dikes (maximum width, visible maximum height and intensity index of clastic dikes) with Ms and local shaking intensity corresponding to the MSK-64 macroseismic intensity scale (Lunina and Gladkov, 2015). The obtained results make basis for modeling the distribution of the geohazard for the purposes of prediction and for estimating the earthquake parameters from liquefaction-induced clastic dikes. The author would like to express their gratitude to the Institute of the Earth's Crust, Siberian Branch of the Russian Academy of Sciences for providing laboratory to carry out this research and Russian Scientific Foundation for their financial support (Grant 14-17-00007).

  13. Past and future trends in concentrations of sulphur and nitrogen compounds in the Arctic

    DEFF Research Database (Denmark)

    Hole, Lars R.; Christensen, Jesper H.; Ruoho-Airola, Tuija;

    2009-01-01

    clear for reduced and oxidized nitrogen. In fact there are positive trends for nitrogen compounds in air at several stations. Acidity is generally reduced at many stations while the precipitation amount is either increasing or stable. Variability of sulphate concentrations in air for the period 1991...... Arctic deposition can be expected. This is because South-East Asian emissions have small influence north of the Arctic circle....

  14. Hirnantian Isotope Carbon Excursion in Gorny Altai, southwestern Siberia

    Directory of Open Access Journals (Sweden)

    Nikolay V. Sennikov

    2015-08-01

    Full Text Available The Hirnantian Isotope Carbon Excursion (HICE, a glaciation-induced positive δ13C shift in the end-Ordovician successions, has been widely used in chemostratigraphic correlation of the Ordovician–Silurian boundary beds in many areas of the world. However, large regions with Ordovician sediments in Siberia are almost unstudied for stable isotope chemostratigraphy. The Burovlyanka section in the Altai area is one of the rare Hirnantian–Rhuddanian sections with both carbonates and graptolitiferous shales occurring in the succession. Here we report the discovery of the HICE in the uppermost beds of the Tekhten¢ Formation, the Dalmanitina Beds in the Burovlyanka section. The Dalmanitina limestone Member between the graptolitiferous shales may correspond to the mid-Hirnantian glacial episode, which led to a global sea level drop and major extinction of marine fauna.

  15. Cold as Metaphor of Siberia (19th Century Representations

    Directory of Open Access Journals (Sweden)

    Degaltseva E. A.

    2012-01-01

    Full Text Available The article is focused on discourse and fantasy studies representing Siberia in social mythology as one of the relevant and topical directions in the identity studies. Techniques of forming different myths uniting the society as a whole are presented. A mythologem “Siberia” together with various metaphorical characteristics (cold, snow, hard labour, clear became unifying for ethnic and social groups of the region. Siberian literature plays an important role in forming the concept “Siberian” in numerous poetic texts serving as codes and messages in the communication process. The conflict in interpreting symbols connected with the concept-mythologem “Siberia” is rather vague in the traditional society as it is related to the general world view setting of the communication subjects.

  16. Collembola and Oribatei of brown coal dumps in Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Stebaeva, S.K.; Andrievsky, V.S. [Russian Academy of Sciences, Novobirsk (Russian Federation)

    1997-09-01

    Nature and rates of forming Collembola and Oribatei groups in catena of technogenic ecosystems on brown coal dumps in Siberia were studied. With increasing age of dumps, the taxonomic diversity and abundance of microarthropod groups increase, the dominance structure is transformed. Colonization of technogenic landscapes by Collembola proceeds faster than that by Oribatei, especially at initial and middle stages of forming the groups resulting in the sharp increase of species abundance and diversity. At the late successional stage the rates of colonizing dumps by Collembola and Oribatei become identical due to increasing the rate of forming the Oribatei group. The dominance structure in microarthropod groups is transformed during succession and becomes similar to the structure, characteristic of the groups from undisturbed meadow ecosystems. In Oribatei this is displayed more distinctly, but in both groups the indicator species for technogenic ecosystems are distinguished.

  17. Paleobiology of the Mesoproterozoic Billyakh Group, Anabar Uplift, northern Siberia

    Science.gov (United States)

    Sergeev, V. N.; Knoll, A. H.; Grotzinger, J. P.

    1995-01-01

    Silicified peritidal carbonates of the Mesoproterozoic Kotuikan and Yusmastakh Formations, Anabar Uplift, northeastern Siberia, contain exceptionally well-preserved microfossils. The assemblage is dominated by ellipsoidal akinetes of nostocalean cyanobacteria (Archaeoellipsoides) and problematic spheroidal unicells (Myxococcoides); both are allochthonous and presumably planktonic. The assemblage also includes distinctive mat-forming scytonematacean and entophysalidacean cyanobacteria, diverse short trichomes interpreted as cyanobacterial hormogonia or germinated akinetes, rare longer trichomes, and several types of colonial unicells. Although many taxa in the Kotuikan-Yusmastakh assemblage are long-ranging prokaryotes, the overall character of the assemblage is distinctly Mesoproterozoic, with its major features shared by broadly coeval floras from Canada, China, India, and elsewhere in Siberia. Microfossils also occur in middle to inner shelf shales of the Ust'-Il'ya and lower Kotuikan Formations. Leiosphaerid acritarchs (up to several hundred microns in diameter) characterize this facies. As in other Mesoproterozoic acritarch assemblages, acanthomorphic and other complex forms that typify Neoproterozoic assemblages are absent. The combination in Billyakh assemblages of exceptional preservation and low eukaryotic diversity supports the hypothesis that nucleated organisms diversified markedly near the Mesoproterozoic-Neoproterozoic boundary. The assemblages also demonstrate the antiquity of cyanobacteria capable of cell differentiation and suggest the importance of both changing peritidal substrates and evolving eukaryotes in determining stratigraphic patterns of Proterozoic prokaryotes. The permineralized assemblage contains 33 species belonging to 17 genera. Ten new species or new combinations are proposed: Archaeoellipsoides costatus n. sp., A. elongatus n. comb., A. dolichos n. comb., A. minor n. nom., A. crassus n. comb., A. major n. comb., A. bactroformis n

  18. Human evolution in Siberia: from frozen bodies to ancient DNA

    Directory of Open Access Journals (Sweden)

    Bouakaze Caroline

    2010-01-01

    Full Text Available Abstract Background The Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horse-breeding economy as well as their Turkic language. On the basis of ethnological and linguistic criteria as well as population genetic studies, it has been assumed that they originated from South Siberian populations. However, many questions regarding the origins of this intriguing population still need to be clarified (e.g. the precise origin of paternal lineages and the admixture rate with indigenous populations. This study attempts to better understand the origins of the Yakuts by performing genetic analyses on 58 mummified frozen bodies dated from the 15th to the 19th century, excavated from Yakutia (Eastern Siberia. Results High quality data were obtained for the autosomal STRs, Y-chromosomal STRs and SNPs and mtDNA due to exceptional sample preservation. A comparison with the same markers on seven museum specimens excavated 3 to 15 years ago showed significant differences in DNA quantity and quality. Direct access to ancient genetic data from these molecular markers combined with the archaeological evidence, demographical studies and comparisons with 166 contemporary individuals from the same location as the frozen bodies helped us to clarify the microevolution of this intriguing population. Conclusion We were able to trace the origins of the male lineages to a small group of horse-riders from the Cis-Baïkal area. Furthermore, mtDNA data showed that intermarriages between the first settlers with Evenks women led to the establishment of genetic characteristics during the 15th century that are still observed today.

  19. Source Attribution of Light-absorbing Aerosols in Arctic Snow (Invited)

    Science.gov (United States)

    Hegg, D.; Warren, S. G.; Grenfell, T. C.; Doherty, S. J.; Larson, T. V.; Clarke, A. D.

    2010-12-01

    Light-absorbing aerosols (LAA) deposited on the arctic snow pack, in particular black carbon (BC), contribute appreciably to the arctic radiation budget and their reduction has been suggested as a means to attenuate warming in the arctic. Effective prediction and mitigation of Arctic snow LAA requires that the sources of the LAA be elucidated. To this end, receptor modeling in the form of Positive Matrix Factorization (PMF) has been exercised on a data set of chemical concentrations in snow of various species (including inorganic and organic acids, carbohydrates and selected other organics as well as LAA) derived from an extensive set of snow samples from locations in Russia (including Siberia), Canada, Greenland, the Arctic Ocean and Svalbard. The data were obtained in three distinct periods: spring of 2007, spring of 2008, and spring of 2009. Data from each period were analyzed separately (note that the Svalbard data were analyzed only recently and were not included in the published 2007 analysis). Aerosol light absorption was determined spectrophotometrically at multiple wavelengths on filters through which melted snow was filtered. Based on the Angstrom exponent of the light absorption, partitioning of the absorption between BC and other LAA species was estimated. Statistics of the LAA concentrations for the Arctic as a whole and the geographic distribution of BC and other LAA species are presented. PMF analysis of the filtrate and filters from the 2007 data set from western Siberia, the Canadian lower arctic and Greenland revealed four factors or sources: two distinct biomass burning sources, a pollution source and a marine source. The first three of these were responsible for essentially all of the black carbon, with the two biomass sources together accounting for > 90% of the black carbon. Geographically, the biomass sources were dominant for all regions except the Arctic Ocean near the North Pole. For the 2008 and 2009 data sets, from eastern Siberia and

  20. 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.

  1. Trace metal distribution in pristine permafrost-affected soils of the Lena River Delta and its Hinterland, Northern Siberia, Russia

    Directory of Open Access Journals (Sweden)

    I. Antcibor

    2013-02-01

    Full Text Available Soils are an important compartment of ecosystems and have the ability to immobilize chemicals preventing their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since the Arctic ecosystems are considered to be very sensitive to climatic changes as well as to chemical contamination. This study characterizes background levels of trace metals in permafrost-affected soils of the Lena River Delta and its hinterland in northern Siberia (73.5° N–69.5° N representing a remote region far from evident anthropogenic trace metal sources. Investigations on total element contents of iron (Fe, arsenic (As, manganese (Mn, zinc (Zn, nickel (Ni, copper (Cu, lead (Pb, cadmium (Cd, cobalt (Co and mercury (Hg in different soil types developed in different geological parent materials have been carried out. The highest concentrations of the majority of the measured elements were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex in the Lena River Delta region. Correlation analyses of trace metal concentrations and soil chemical and physical properties at a Holocene estuarine terrace and two modern floodplain levels in the southern-central Lena River Delta (Samoylov Island showed that the main factors controlling the trace metal distribution in these soils are organic matter content, soil texture and contents of iron and manganese-oxides. Principal Component Analysis (PCA revealed that soil oxides play a significant role in trace metal distribution in both top and bottom horizons. Occurrence of organic matter contributes to Cd binding in top soils and Cu binding in bottom horizons. Observed ranges of the background concentrations of the majority of trace elements were

  2. Relationship between winter air temperature in Eastern China and Arctic Oscillation%中国东部地区冬季气温与北极涛动的关系

    Institute of Scientific and Technical Information of China (English)

    雷杨娜; 孙娴; 乐章燕

    2014-01-01

    Using the NCEP/NCAR reanalysis data,Arctic Oscillation (AO)index series and monthly temperature at 160 weather stations in China,variation characteristics of winter air temperature and AO index series as well as both relationships from 195 1 to 2007 were analyzed.The results show that there is a positive correlation relation-ship between winter air temperature and AO indexes in the Eastern China.Winter air temperature index and Arctic Oscillation index both increase gradually.Their annual and inter-decadal variations are significant and both have a 1 8 years cycle.According to the partial correlation coefficient,effects of the Siberia high on winter air temperature in the Eastern China are significant on annual scale,while the AO index has not a significant correlation with win-ter air temperature;effects of AO on winter air temperature are more significant than that of the Siberia high on in-terdecadal scale.Winter air temperature and AO index in the Eastern China are high when the East Asian trough is weak,and vice versa.On inter-annual scale,the East Asian though has significant effect on inter-annual variations of winter air temperature of Eastern China,while the correlation between AO and winter air temperature is not sig-nificant;on interdecadal scale,effects of AO index and the East Asian though on winter air temperature changes in the Eastern China are significant.%利用NCEP/NCAR再分析资料、北极涛动(AO)指数序列及中国160个台站月温度资料,分析1951-2007年中国东部地区冬季气温与AO指数的变化特征及其相互关系。结果表明:1951-2007年AO指数与中国东部地区冬季气温指数基本呈正相关关系。中国东部地区冬季气温指数(IWT)与北极涛动指数(IAO )均逐渐增强,并有显著的年际和年代际变化,均存在准18 a周期变化特征。从偏相关系数来看,在年际尺度上,西伯利亚高压对中国东部地区冬季气温的年际变化影响较大,

  3. Technological and environmental challenges of Arctic shipping—a case study of a fictional voyage in the Arctic

    Directory of Open Access Journals (Sweden)

    Lars-Henrik Larsen

    2016-05-01

    Full Text Available Shipping in Arctic seas is challenging and poses an environmental risk. This paper presents a fictional case involving a multipurpose supply vessel transporting one large object (a 750-tonne compressor and 24 containers loaded with chemicals and equipment for use by the petroleum industry in western Siberia. With technical details representative of vessels navigating the Arctic today, the fictitious ship Oleum has an ice class sufficient for navigating unaccompanied in the Barents and Kara seas, so no assistance is in range when, in late October, clogged fuel filters cause engine failure and the vessel eventually drifts ashore. Heeling over, Oleum loses both cargo and marine diesel oil. The scenario includes a successful helicopter rescue of the 16 crewmembers and a partial recovery of oil and chemicals by booms and skimmers. Recovery of chemicals with physical properties not allowing mechanical collection is not attempted. The scenario ends as the abandoned wreck is broken down at the stranding location, and containers rupture and discharge their cargo. The scenario postulates a moderate and short-lived environmental impact. The most visible effects of the grounding are the hull itself, the compressor and the spreading effects and degradation of oil and chemicals unmanageable for the clean-up operations.

  4. INNOVATIVE REGIONAL DEVELOPMENT: NEEDS FOR DIVERSIFIED ECONOMIC GROWTH OF SIBERIA UNDER THE CONDITIONS OF REINDUSTRIALIZATION

    OpenAIRE

    Sumina, E.; Zyablikov, D.

    2015-01-01

    The article investigates the essence and the priority of economy reindustrialization in Siberia taking into accounts the needs and characteristics of the innovation development of raw materials regions. The issue of developing the theoretical approaches to the formation of innovative regional development strategy is in the foreground, taking into account technological modernization priorities in Siberia. The aim of the given work is to determine the role of the rocket and space industry in th...

  5. Formation of phreatomagmatic pipes in the Tunguska Basin (Siberia, Russia) during the end-Permian

    Science.gov (United States)

    Polozov, Alexander; Svensen, Henrik; Planke, Sverre

    2010-05-01

    We recently proposed that numerous pipes piercing sedimentary rocks of Tunguska Basin triggered the Permian-Triassic mass extinction (Svensen et al., 2009). Large amounts of greenhouse and poisonous gases were released through the pipes and into P-Tr atmosphere, partly formed by heating of petroleum-bearing evaporites. The sub-volcanic part of the Siberian Traps was emplaced in the Tunguska Basin sedimentary sequences, which includes Pre-Cambrian source rocks, Early Cambrian evaporites, and Paleozoic terrigenous and coal-bearing rocks. Spectacular breccia pipes are numerous in the evaporate-parts of the basin, and are filled with volcaniclastic rocks and commercial magnetite mineralization. Although these pipes have been intensively studied in order to understand the iron ore formation, the origin and formation of the pipes is poorly understood. Many researchers emphasize that magma-sediments interaction as a key reason of pipe formation, whereas phreatomagmatic hypothesis are also proposed. In order to improve the understanding of pipe formation and ore-deposition, we have studied a basalt-rich breccia pipe piercing Cambrian evaporates at the Nepa locality in East Siberia. Textural features of the volcanic fragments in the breccias include lapilli, Pele's hear, glassy basalt and dolerite clasts, blocks of tuffs in addition to sedimentary rocks. Calcite and halite are the most common types of cement. We have studied minerals from the breccia cement and from reaction rims around clasts in order to understand the hydrothermal system that developed after the pipe formed. Calcite and dolomite are the dominating carbonates, and two types of anhydrite is present. Biotite, Cl-Fe-bearing amphibole (hastingsite), and Cl-F-apatite are amongst early hydrothermal minerals covering magmatic clast and lapillies. Our new data confirm (i) the phreatomagmatic nature of breccia filling in the Tunguska Basin pipes and (ii) the key role of sedimentary brine and petroleum involved in

  6. More Arctic research needed

    Science.gov (United States)

    Bush, Susan

    The desire to achieve a balance between Arctic and Antarctic study was the message of the Senate Committee on Commerce, Science, and Transportation, which heard testimony on the need for more Arctic research on April 24. Ted Stevens (R-Alaska) noted that since 1986, study in the area has not increased as the National Science Foundation has claimed, but rather, owing to inflation, has merely kept pace. Robert Correll, assistant director of geosciences at NSF and chair of the Interagency Arctic Oceans Working Group, gave several reasons why the Arctic is an important area for study by the scientific community. Its unique environment, he said, makes it a natural laboratory. And due to its environmental sensitivity, it may provide one of the earliest indicators of global climate change. Also, its geographic location makes it a “window on space,” some of the world's largest mineral and petroleum resources are in the Arctic, and the region has great strategic and military importance.

  7. Russian Arctic Petroleum Resources Ressources pétrolières de l’Arctique russe

    Directory of Open Access Journals (Sweden)

    Zolotukhin A.

    2011-12-01

    Full Text Available The Arctic continental shelf is believed to be the area with the highest unexplored potential for oil and gas as well as for unconventional hydrocarbon resources such as gas hydrates. Despite a common view that the Arctic has plentiful of hydrocarbon resources, there are ongoing debates regarding the potential of this region as a future energy supply base. Driving forces for such discussions are geopolitics, environmental concern, assessment and delineation of Arctic resources, technology available for their successful development and the market demand for energy supply. The Russian part is recognized to be the largest among oil and gas resources owned by Arctic nations. However, scarce information and available geological data create uncertainty regarding a future role of the Russian Arctic as main base of energy supply in the second part of the XXI century. A further uncertainty is the pace at which production from northern areas including the Arctic will be brought onstream – either because of national policy, infrastructure development or investment by the state and the oil companies. These areas embrace those where development has already been started (Offshore Sakhalin, northern Timan Pechora and those awaiting future involvement, like Barents and Pechora seas, East Siberia, Yamal, Kara Sea and Kamchatka. Offhore production levels are likely to be very important to Russia in mid and long terms, especially as most (if not all production will go for export and, in the process, open doors to new markets. In this way, offshore production will introduce a new and very significant component to Russia’s export strategy. However, active involvement of the Russian Arctic resources in the global energy supply process needs a detailed analysis and clear understanding of the market potential for Russian gas and oil (required volumes, time frame, transportations routes and requires close attention of the government to the most important issues that

  8. The effects of climate, permafrost and fire on vegetation change in Siberia in a changing climate

    International Nuclear Information System (INIS)

    Observations and general circulation model projections suggest significant temperature increases in Siberia this century that are expected to have profound effects on Siberian vegetation. Potential vegetation change across Siberia was modeled, coupling our Siberian BioClimatic Model with several Hadley Centre climate change scenarios for 2020, 2050 and 2080, with explicit consideration of permafrost and fire activity. In the warmer and drier climate projected by these scenarios, Siberian forests are predicted to decrease and shift northwards and forest-steppe and steppe ecosystems are predicted to dominate over half of Siberia due to the dryer climate by 2080. Despite the large predicted increases in warming, permafrost is not predicted to thaw deep enough to sustain dark (Pinus sibirica, Abies sibirica, and Picea obovata) taiga. Over eastern Siberia, larch (Larix dahurica) taiga is predicted to continue to be the dominant zonobiome because of its ability to withstand continuous permafrost. The model also predicts new temperate broadleaf forest and forest-steppe habitats by 2080. Potential fire danger evaluated with the annual number of high fire danger days (Nesterov index is 4000-10 000) is predicted to increase by 2080, especially in southern Siberia and central Yakutia. In a warming climate, fuel load accumulated due to replacement of forest by steppe together with frequent fire weather promotes high risks of large fires in southern Siberia and central Yakutia, where wild fires would create habitats for grasslands because the drier climate would no longer be suitable for forests.

  9. The effects of climate, permafrost and fire on vegetation change in Siberia in a changing climate

    Energy Technology Data Exchange (ETDEWEB)

    Tchebakova, N M; Parfenova, E [V N Sukachev Institute of Forest, Siberian Branch of the Russian Academy of Sciences, Academgorodok, Krasnoyarsk, 660036 (Russian Federation); Soja, A J, E-mail: ncheby@forest.akadem.r, E-mail: Amber.J.Soja@nasa.go [National Institute of Aerospace (NIA), NASA Langley Research Center, Climate Sciences, 21 Langley Boulevard, Mail Stop 420, Hampton, VA 23681-2199 (United States)

    2009-10-15

    Observations and general circulation model projections suggest significant temperature increases in Siberia this century that are expected to have profound effects on Siberian vegetation. Potential vegetation change across Siberia was modeled, coupling our Siberian BioClimatic Model with several Hadley Centre climate change scenarios for 2020, 2050 and 2080, with explicit consideration of permafrost and fire activity. In the warmer and drier climate projected by these scenarios, Siberian forests are predicted to decrease and shift northwards and forest-steppe and steppe ecosystems are predicted to dominate over half of Siberia due to the dryer climate by 2080. Despite the large predicted increases in warming, permafrost is not predicted to thaw deep enough to sustain dark (Pinus sibirica, Abies sibirica, and Picea obovata) taiga. Over eastern Siberia, larch (Larix dahurica) taiga is predicted to continue to be the dominant zonobiome because of its ability to withstand continuous permafrost. The model also predicts new temperate broadleaf forest and forest-steppe habitats by 2080. Potential fire danger evaluated with the annual number of high fire danger days (Nesterov index is 4000-10 000) is predicted to increase by 2080, especially in southern Siberia and central Yakutia. In a warming climate, fuel load accumulated due to replacement of forest by steppe together with frequent fire weather promotes high risks of large fires in southern Siberia and central Yakutia, where wild fires would create habitats for grasslands because the drier climate would no longer be suitable for forests.

  10. Observation Analysis on Impact of Arctic Ozone Depletion on Surface Air Temperature in Middle and High Latitudes of East Asia during Springtime%北极臭氧损耗对初春东亚中高纬地区地面气温影响的观测分析

    Institute of Scientific and Technical Information of China (English)

    石柳; 郑明华; 付遵涛

    2011-01-01

    Using the composited analysis method,the impact of Arctic ozone depletion on surface air temperature in middle and high latitudes of the East Asia during springtime is studied.It is found that,in the low(high) ozone years,the positive(negative) temperature anomaly occur in middle and high latitudes of East Asia in March.Similar to March,the anomaly still exist in April,but with small amplitude and shrinked range.Comparing with these results,the composition of the years of lower and higher AO indexes appear to be similar on amplitude,its center location is different.In the weaker years from the AO phase,those anomalies are still significant.So ozone as an eternal forcing,it has a significant impact on the temperature of Northern Hemisphere,it might first effects on the Arctic region,and then effects the region of middle and high latitudes by self-correlation in space.%利用1948—2007年NCEP/NCAR月平均2m地面气温再分析资料、3月北极涛动(AO)指数和春季臭氧含量资料,采用合成分析方法分析了北极臭氧损耗对初春东亚中高纬地区地面气温的影响。结果表明,臭氧低(高)值年,3月东亚中高纬地区地面气温存在正(负)异常。4月的与3月类似,但气温异常的幅度减小,中心位置也有所变化。对比分析表明,1979年以后的AO正位相和臭氧损耗对3月东亚地面气温的影响类似,但在影响范围和中心位置上有所不同。在AO位相不明显的年份,臭氧损耗年3月东亚地区地面气温的异常依然显著。臭氧作为一个外界强迫因子,对北半球大气温度有显著的影响,可能首先影响极地气温并最终通过空间上的自相关影响中高纬度的地面气温变化。

  11. Ground and aircraft-based methane measurements in Siberia: source attribution using tracers and models

    Science.gov (United States)

    Arzoumanian, E.; Paris, J. D.; Pruvost, A.; Peng, S.; Turquety, S.; Berchet, A.; Pison, I.; Helle, J.; Arshinov, M.; Belan, B. D.

    2015-12-01

    Methane (CH4) is the second most important anthropogenic greenhouse gas. It is also naturally emitted by a number of processes, including microbial activity in wetlands, permafrost degradation and wildfires. Our current understanding of the extent and amplitude of its natural sources, as well as the large scale driving factors, remain highly uncertain (Kirschke et al., Nature Geosci., 2013). Furthermore, high latitude regions are large natural sources of CH4 in the atmosphere. Observing boreal/Arctic CH4 variability and understanding its main driving processes using atmospheric measurements and transport model is the task of this work. YAK-AEROSIB atmospheric airborne campaigns (flights in the tropospheric layer up to 9 km connecting the two cities of Novosibirsk and Yakutsk) and continuous measurements at Fonovaya Observatory (60 km west of Tomsk - 56° 25'07"N, 84° 04'27"E) have been performed in order to provide observational data on the composition of Siberian air. The study is focused on 2012, during which a strong heat wave impacted Siberia, leading to the highest mean daily temperature values on record since the beginning of the 20th century. This abnormal drought has led to numerous large forest fires. A chemistry-transport model (CHIMERE), combined with datasets for anthropogenic (EDGAR) emissions and models for wetlands (ORCHIDEE) and wildfires (APIFLAME), is used to determine contributions of CH4 sources in the region. Recent results concerning CH4 fluxes and its atmospheric variability in the Siberian territory derived from a modeled-based analysis will be shown and discussed. This work was funded by CNRS (France), the French Ministry of Foreign Affairs, CEA (France), Presidium of RAS (Program No. 4), Brunch of Geology, Geophysics and Mining Sciences of RAS (Program No. 5), Interdisciplinary integration projects of Siberian Branch of RAS (No. 35, No. 70, No. 131), Russian Foundation for Basic Research (grants No 14-05-00526, 14-05-00590). Kirschke, S

  12. Fire effects on methane emissions from a larch forest in Northeastern Siberia

    Science.gov (United States)

    Kuhn, M. A.; Schade, J. D.; Natali, S.; Spawn, S.

    2015-12-01

    Understanding how boreal forest fires affect the fate of soil carbon in northern permafrost regions is critical to our understanding of feedbacks from Arctic ecosystems on global climate change. The frequency and intensity of fires have been increasing across the northern boreal and tundra region. Fire makes permafrost vulnerable because it removes the insulating plant and organic layers. The removal of these insulating layers in Siberian larch forests underlain by ice and carbon rich permafrost can lead to ground subsidence and saturate soils. Saturated and anoxic soils are ideal conditions for the production of methane, which is ~30x more effective at trapping heat than carbon dioxide. Most boreal ecosystems are currently considered to be sinks for methane, but not much research has been done to study how fire may affect methane production in these regions. We predict that fires will increase methane production in boreal ecosystems underlain by permafrost due to increases in thaw depth, ice wedge thawing, and ground subsidence. This study focused on a ten-year old burn site composed of mainly larch trees and tussocks located near the bank of the Kolyma River in Northeastern Siberia. The ground of the burn site was substantially more subsided and had larger areas of surface water and saturated soils than the nearby unburned forest. We investigated the flux of methane from the surfaces of small ponds that formed over thawing ice wedges and in the subsided depressions. While previous studies have reported low dissolved organic carbon concentrations in streams affected by fire in permafrost regions, we found high DOC concentrations in pond water (21-27 mg/L). Methane fluxes from ice wedge ponds ranged from 20 to 180 mg CH4 m-2 d-1. These values are comparable to fluxes from other permafrost ecosystems including bogs, wet tundra, and fens that are considered globally significant sources of CH4. Additionally, the burned forest contained some subsided areas that were

  13. Assessing Silicate Weathering in Permafrost-Dominated Catchments Using Lithium Isotopes: The Lena River, Siberia

    Science.gov (United States)

    Murphy, M. J.; Pogge von Strandmann, P.; Porcelli, D.; Katchinoff, J. A.; Moreras Martí, A.; Hirst, C. A.; Andersson, P. S.; Maximov, T. C.

    2015-12-01

    Rising global temperatures have the potential to influence the Earth's climate feedback cycles due to permafrost thawing, altering the freshwater input and trace metal and carbon fluxes into the ocean and atmosphere. Riverine lithium isotope ratios (d7Li) are a tracer of silicate weathering processes, which are key in the removal of atmospheric CO2 over geological timescales. Despite this, little is known about the effects of permafrost thawing on d7Li variations. Strong seasonal changes in the thawed active layer thickness dictate surficial water flow paths, which may influence intra-annual riverine d7Li signatures. We present a study of the dissolved d7Li from the large permafrost-dominated watersheds of the Lena River (Siberia), which drain into the Arctic Ocean. This work comprises a temporal study during the May 2015 spring flood, from ice breakup through peak flooding, thus monitoring changes in water-rock and water-soil interaction, both processes that control weathering and hence Li isotopes. Before riverine ice started to break up, high [Li] are observed as the river signature is governed by winter base flow conditions. As the river ice breaks up, surface runoff flows over the impermeable permafrost, interacting with leaf litter, diluting the [Li]. We compare d7Li over the spring flood period with a greater spatial study conducted over two summer field seasons (2012/2013) of the main Lena River channel and its tributaries, which drain a variety of lithologies/topographies. During the summer, the thawed active layer promotes deeper water flow paths, greater water-rock interaction and enhanced secondary minerals formation which preferentially take up 6Li. Summer riverine d7Li typically fall between +14.5 ‰ to +28.5 ‰, with rivers draining the Central Siberian Plateau typically exhibiting high [Li], but similar δ7Li to rivers draining the Verkhoyansk Mountain Range. Overall, this study demonstrates how Li isotopes respond to weathering in a permafrost

  14. Changes in atmospheric chemical composition determined from ice core records in southwestern Siberia during the twentieth century

    Science.gov (United States)

    Joswiak, Daniel R.

    The presented research includes analysis and interpretation of the upper 50 m of a deep ice core which was drilled at 49°48'22"N, 86°33'52" (4115 m.a.s.l.) on the Belukha Plateau, Altai, in southwestern Siberia. The main goal was to examine variability of geochemical records preserved in the ice in relation to climatic and environmental changes; and to determine the main aerosol sources using ground- and upper-level meteorological data. Ion chromatography was used to determine concentrations of anions (SO4, NO3, NO2, Cl), cations (NH4, Ca, K, Mg, Na), the carboxylic (organic) acids acetate (CH3COOH), formate (HCOOH), oxalate (C2O4), and methanesulfonic acid (CH3SO 3H). Major ion concentrations were dominated by sulfate (30.3%), nitrate (18.1%), formate (15.0%), and ammonium (12.4%). Highest concentrations were observed for sulfate; over 1460 ppb. Laser particle counting was used to determine size resolved number concentrations of particles ranging from 0.5 to 16.0 mum. Logarithmic distribution of particles was observed, with over 90% of the particle number concentration coming from particles less than 1.4 mum. Particle mass, calculated from the number concentration, revealed the greatest contribution (59%) to mass arrived with medium size particles (4.0-8.0 microm). Back-trajectories were modeled using NOAA's Hyplit model were modeled for the four days of maximum annual precipitation during a year of increased (1991) and decreased (1990) ion and particle concentrations. Principle components factor analysis was used to determine the main aerosol sources. The upper 50 m covers the time period from 1917 to 2002. Glacier flow models indicated the full depth of 170 m should provide over 1000 years of records. Insoluble particle concentrations preserved in the ice core were affected mainly by climatic conditions including precipitation regimes and wind speed variability. The small size particles (0.5-1.0 mm) are transported inter-continentally and associated with

  15. Paleodistribution modeling suggests glacial refugia in Scandinavia and out-of-Tibet range expansion of the Arctic fox.

    Science.gov (United States)

    Fuentes-Hurtado, Marcelo; Hof, Anouschka R; Jansson, Roland

    2016-01-01

    Quaternary glacial cycles have shaped the geographic distributions and evolution of numerous species in the Arctic. Ancient DNA suggests that the Arctic fox went extinct in Europe at the end of the Pleistocene and that Scandinavia was subsequently recolonized from Siberia, indicating inability to track its habitat through space as climate changed. Using ecological niche modeling, we found that climatically suitable conditions for Arctic fox were found in Scandinavia both during the last glacial maximum (LGM) and the mid-Holocene. Our results are supported by fossil occurrences from the last glacial. Furthermore, the model projection for the LGM, validated with fossil records, suggested an approximate distance of 2000 km between suitable Arctic conditions and the Tibetan Plateau well within the dispersal distance of the species, supporting the recently proposed hypothesis of range expansion from an origin on the Tibetan Plateau to the rest of Eurasia. The fact that the Arctic fox disappeared from Scandinavia despite suitable conditions suggests that extant populations may be more sensitive to climate change than previously thought. PMID:26811782

  16. International Arctic Research Collaborations: Past, Present and Future

    Science.gov (United States)

    Kintisch, E. S.

    2015-12-01

    International cooperation on Arctic research has a long and storied history, predating even the first International Polar Year in 1881. But scientists want to improve and expand current efforts to conduct international Arctic research, despite politcal and legal barriers that can hamper it. A review of the past and present aspects of such research can inform that effort. As part of a six month fellowship at the Center for Science Diplomacy at the American Association for the Advancement of Science I studied the history and current status of international cooperation in the Arctic. I will report on my findings, which include the fact that some of the first substantial international environmental research and regulatory cooperation began in the far North. My session will identify the elements that make international research collaborations successful, for example more than a century of cooperative work by Russian and Norwegian fishery scientists to monitor and regulate the cod trade in the Barents Sea. And it will explore the challenges that can threaten such collaborations. These can include rules that stymie data collection, block the import of certain analytical equipment across national boundaries, and bar the export of soil or water samples. I will mention specific complications to recent international arctic research projects. These include the SWERUS cruise, a joint effort between Sweden, Russia and the US, an effort to study carbon fluxes over the East Siberian Arctic Shelf in 2014. The session will also review progress towards a new international agreeement, first proposed by the US, on improving arctic research cooperation. That deal is focused on removing the bureacratic and legal barriers to scientists seeking to conduct arctic research on foreign waters and land.

  17. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    The peak of biological activities in Arctic ecosystems is characterized by a relative short and intense period between the start of snowmelt until the onset of frost. Recent climate changes have induced larger seasonal variation in both timing of snowmelt as well as changes mean temperatures and ...... and resources. This poster will present the conceptual framework for this project focusing on species resilience......., an extensive monitoring program has been conducted in the North Eastern Greenland National Park, the Zackenberg Basic. The objective of the program is to provide long time series of data on the natural innate oscillations and plasticity of a High Arctic ecosystem. With offset in the data provided through...

  18. Carbon Cycling in the Arctic Archipelago: The Export of Pacific Carbon to the North Atlantic

    Science.gov (United States)

    Shadwick, E. H.; Papakyriakou, T.; Prowe, A. E. F.; Leong, D.; Moore, S.; Thomas, H.

    2009-04-01

    The Arctic Ocean is expected to be disproportionately sensitive to climatic changes, and thought to be an area where such changes might be detected. The Arctic hydrological cycle is influenced by: runoff and precipitation, sea ice formation/melting, and the inflow of saline waters from Bering and Fram Straits and the Barents Sea Shelf. Pacific water is recognizable as low salinity water, with high concentrations of dissolved inorganic carbon (DIC), flowing from the Arctic Ocean to the North Atlantic via the Canadian Arctic Archipelago. We present DIC data from an east-west section through the Archipelago, as part of the Canadian International Polar Year initiatives. The fractions of Pacific and Arctic Ocean waters leaving the Archipelago and entering Baffin Bay, and subsequently the North Atlantic, are computed. The eastward transport of carbon from the Pacific, via the Arctic, to the North Atlantic is estimated. Altered mixing ratios of Pacific and freshwater in the Arctic Ocean have been recorded in recent decades. Any climatically driven alterations in the composition of waters leaving the Arctic Archipelago may have implications for anthropogenic CO2 uptake, and hence ocean acidification, in the subpolar and temperate North Atlantic.

  19. 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

  20. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Christensen, Tom; Payne, J.; Doyle, M.;

    The Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, established the Circumpolar Biodiversity Monitoring Program (CBMP) to address the need for coordinated and standardized monitoring of Arctic environments. The CBMP includes an international...... on developing and implementing long-term plans for monitoring the integrity of Arctic biomes: terrestrial, marine, freshwater, and coastal (under development) environments. The CBMP Terrestrial Expert Monitoring Group (CBMP-TEMG) has developed the Arctic Terrestrial Biodiversity Monitoring Plan (CBMP......-Terrestrial Plan/the Plan) as the framework for coordinated, long-term Arctic terrestrial biodiversity monitoring. The goal of the CBMP-Terrestrial Plan is to improve the collective ability of Arctic traditional knowledge (TK) holders, northern communities, and scientists to detect, understand and report on long...

  1. Influence of logging on the effects of wildfire in Siberia

    Science.gov (United States)

    Kukavskaya, E. A.; Buryak, L. V.; Ivanova, G. A.; Conard, S. G.; Kalenskaya, O. P.; Zhila, S. V.; McRae, D. J.

    2013-12-01

    The Russian boreal zone supports a huge terrestrial carbon pool. Moreover, it is a tremendous reservoir of wood products concentrated mainly in Siberia. The main natural disturbance in these forests is wildfire, which modifies the carbon budget and has potentially important climate feedbacks. In addition, both legal and illegal logging increase landscape complexity and affect burning conditions and fuel consumption. We investigated 100 individual sites with different histories of logging and fire on a total of 23 study areas in three different regions of Siberia to evaluate the impacts of fire and logging on fuel loads, carbon emissions, and tree regeneration in pine and larch forests. We found large variations of fire and logging effects among regions depending on growing conditions and type of logging activity. Logged areas in the Angara region had the highest surface and ground fuel loads (up to 135 t ha-1), mainly due to logging debris. This resulted in high carbon emissions where fires occurred on logged sites (up to 41 tC ha-1). The Shushenskoe/Minusinsk and Zabaikal regions are characterized by better slash removal and a smaller amount of carbon emitted to the atmosphere during fires. Illegal logging, which is widespread in the Zabaikal region, resulted in an increase in fire hazard and higher carbon emissions than legal logging. The highest fuel loads (on average 108 t ha-1) and carbon emissions (18-28 tC ha-1) in the Zabaikal region are on repeatedly burned unlogged sites where trees fell on the ground following the first fire event. Partial logging in the Shushenskoe/Minusinsk region has insufficient impact on stand density, tree mortality, and other forest conditions to substantially increase fire hazard or affect carbon stocks. Repeated fires on logged sites resulted in insufficient tree regeneration and transformation of forest to grasslands. We conclude that negative impacts of fire and logging on air quality, the carbon cycle, and ecosystem

  2. Circumpolar Arctic greening: Relationships to summer sea-ice concentrations, land temperatures and disturbance regimes

    Science.gov (United States)

    Walker, D. A.; Bhatt, U. S.; Epstein, H. E.; Raynolds, M. K.; Frost, G. V.; Leibman, M. O.; Khomutov, A.; Jia, G.; Comiso, J. C.; Pinzon, J. E.; Tucker, C. J.; Webber, P. J.; Tweedie, C. E.

    2009-12-01

    The global distribution of Arctic tundra vegetation is closely tied to the presence of summer sea ice. Models predict that the reduction of sea ice will cause large changes to summer land-surface temperatures. Warming combined with increased natural and anthropogenic disturbance are expected to greatly increase arctic tundra productivity. To examine where tundra productivity is changing most rapidly, we studied 1982-2008 trends of sea-ice concentrations, summer warmth index (SWI) and the annual Maximum Normalized Difference Vegetation Index (MaxNDVI). We summarize the results according to the tundra adjacent to 14 Arctic seas. Sea-ice concentrations have declined and summer land temperatures have increased in all parts of the Arctic coast. The overall percentage increase in Arctic MaxNDVI was +7%. The trend was much greater in North America (+11%) than in Eurasia (+4%). Large percentage increases of MaxNDVI occurred inland from Davis Straight (+20%), Baffin Bay (+18%), Canadian Archipelago (+14%), Beaufort Sea (+12%), and Laptev Sea (+8%). Declines occurred in the W. Chukchi (-6%) and E. Bering (-5%) seas. The changes in NDVI are strongly correlated to changes in summer ground temperatures. Two examples from a 900-km north-south Arctic transect in Russia and long-term observations at a High Arctic site in Canada provide insights to where the changes in productivity are occurring most rapidly. At tree line near Kharp in northwest Siberia, alder shrubs are expanding vigorously in fire-disturbed areas; seedling establishment is occurring primarily in areas with disturbed mineral soils, particularly nonsorted circles. In the Low Arctic tundra areas of the central Yamal Peninsula greening is concentrated in riparian areas and upland landslides associated with degrading massive ground ice, where low-willow shrublands replace the zonal sedge, dwarf-shrub tundra growing on nutrient-poor sands. In polar desert landscapes near the Barnes Ice Cap, Baffin Island, Canada

  3. A multi-model assessment of pollution transport to the Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Shindell, D T; Chin, M; Dentener, F; Doherty, R M; Faluvegi, G; Fiore, A M; Hess, P; Koch, D M; MacKenzie, I A; Sanderson, M G; Schultz, M G; Schulz, M; Stevenson, D S; Teich, H; Textor, C; Wild, O; Bergmann, D J; Bey, I; Bian, H; Cuvelier, C; Duncan, B N; Folberth, G; Horowitz, L W; Jonson, J; Kaminski, J W; Marmer, E; Park, R; Pringle, K J; Schroeder, S; Szopa, S; Takemura, T; Zeng, G; Keating, T J; Zuber, A

    2008-03-13

    We examine the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East and South Asia, and North America using results from a coordinated model intercomparison. These sensitivities to regional emissions (mixing ratio change per unit emission) vary widely across models and species. Intermodel differences are systematic, however, so that the relative importance of different regions is robust. North America contributes the most to Arctic ozone pollution. For aerosols and CO, European emissions dominate at the Arctic surface but East Asian emissions become progressively more important with altitude, and are dominant in the upper troposphere. Sensitivities show strong seasonality: surface sensitivities typically maximize during boreal winter for European and during spring for East Asian and North American emissions. Mid-tropospheric sensitivities, however, nearly always maximize during spring or summer for all regions. Deposition of black carbon (BC) onto Greenland is most sensitive to North American emissions. North America and Europe each contribute {approx}40% of total BC deposition to Greenland, with {approx}20% from East Asia. Elsewhere in the Arctic, both sensitivity and total BC deposition are dominated by European emissions. Model diversity for aerosols is especially large, resulting primarily from differences in aerosol physical and chemical processing (including removal). Comparison of modeled aerosol concentrations with observations indicates problems in the models, and perhaps, interpretation of the measurements. For gas phase pollutants such as CO and O{sub 3}, which are relatively well-simulated, the processes contributing most to uncertainties depend on the source region and altitude examined. Uncertainties in the Arctic surface CO response to emissions perturbations are dominated by emissions for East Asian sources, while uncertainties in transport, emissions, and oxidation are comparable for European

  4. Middle East

    International Nuclear Information System (INIS)

    This document summarizes in a series of tables and graphs the energy profile of Middle East: production, imports, exports, stock change and consumption of crude oil and LNG, oil products, natural gas, coal and lignite, electricity, global primary consumption and energy balance. (J.S.)

  5. 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

  6. Some discussions on Arctic vortex

    Institute of Scientific and Technical Information of China (English)

    Li Hai; Sun Lantao; Wu Huiding; Li Xiang

    2006-01-01

    The Arctic vortex is a persistent large-scale cyclonic circulation in the middle and upper troposphere and the stratosphere. Its activity and variation control the semi-permanent active centers of Pan-Arctic and the short-time cyclone activity in the subarctic areas. Its strength variation, which directly relates to the atmosphere, ocean, sea ice and ecosystem of the Arctic, can affect the lower atmospheric circulation, the weather of subarctic area and even the weather of middle latitude areas. The 2003 Chinese Second Arctic Research Expedition experienced the transition of the stratosphereic circulation from a warm anticyclone to a cold cyclone during the ending period of Arctic summertime, a typical establishing process of the polar vortex circulation. The impact of the polar vortex variation on the low-level circulation has been investigated by some scientists through studying the coupling mechanisms of the stratosphere and troposphere. The impact of the Stratospheric Sudden Warming (SFW) events on the polar vortex variation was drawing people's great attention in the fifties of the last century. The Arctic Oscillation (AO) , relating to the variation of the Arctic vortex, has been used to study the impact of the Arctic vortex on climate change. The recent Arctic vortex studies are simply reviewed and some discussions on the Arctic vertex are given in the paper. Some different views and questions are also discussed.

  7. Glacial Refugium of Pinus pumila (Pall.) Regel in Northeastern Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Shilo, N A; Lozhkin, A V; Anderson, P M; Brown, T A; Pakhomov, A Y; Solomatkina, T B

    2007-02-10

    One of the most glowing representatives of the Kolyma flora [1], ''Pinus pumila'' (Pall.) Regel (Japanese stone pine), is a typical shrub in larch forests of the northern Okhotsk region, basins of the Kolyma and Indigirka rivers, and high-shrub tundra of the Chukchi Peninsula. It also forms a pine belt in mountains above the forest boundary, which gives way to the grass-underbrush mountain tundra and bald mountains. In the southern Chukchi Peninsula, ''Pinus pumila'' along with ''Duschekia fruticosa'' (Rupr.) Pouzar and ''Betula middendorffii'' Trautv. et C. A. Mey form trailing forests transitional between tundra and taiga [2]. Pinus pumila pollen, usually predominating in subfossil spore-and-pollen spectra of northeastern Siberia, is found as single grains or a subordinate component (up 2-3%, rarely 10%) in spectra of lacustrine deposits formed during the last glacial stage (isotope stage 2) in the Preboreal and Boreal times of the Holocene. Sometimes, its content increases to 15-22% in spectra of lacustrine deposits synchronous to the last glacial stage near the northern coast of the Sea of Okhotsk [3], evidently indicating the proximity of Japanese stone pine thickets.

  8. Bazhen Fm matured reservoir evaluation (West Siberia, Russia)

    Science.gov (United States)

    Parnachev, S.; Skripkin, A.; Baranov, V.; Zakharov, S.

    2015-02-01

    The depletion of the traditional sources of hydrocarbons leads to the situation when the biggest players of the oil and gas production market turn to unconventional reserves. Commercial shale oil and gas production levels in the USA have largely determined world prospects for oil and gas industry development. Russia takes one of the leading place in the world in terms of shale oil resources. The main source rock of the West Siberia, the biggest oil and gas basin in Russia under development, the Bazhen Fm and its stratigraphic and lithologic analogs, is located in the territory of over 1,000,000 square kilometers. Provided it has similar key properties (organic carbon content, porosity, permeability) with the deposits of the Bakken Fm and Green River Fm, USA, it is still extremely poorly described with laboratory methods. We have performed the laboratory analysis of core samples from a well drilled in Bazhen Fm deposits with matured organic matter (Tmax>435 °C). It was demonstrated the applicability of the improved steady-state gas flow method to evaluate the permeability of nanopermeable rocks. The role of natural fracturing in forming voids was determided that allows regarding potential Bazhen Fm reservoirs as systems with dual porosity and dual permeability.

  9. Communities of larger fungi of ombrotrophic bogs in West Siberia

    Directory of Open Access Journals (Sweden)

    N.V. Filippova

    2014-11-01

    Full Text Available Bogs are common ecosystems in the Taiga of West Siberia. Little is known about mycological diversity in these important ecosystems. This article summarises the results of a two-year study of the macrofungi in two bogs near the town of Khanty-Mansiysk. Sporocarps were collected in 20 plots (about 300 m2 established in Mukhrino Bog as well as during random walks in Mukhrino Bog and Chistoe Bog in the late summer–autumn of 2012 and 2013. The plots were established in two common bog habitats representing the Ledo-Sphagnetum fusci (LS and Scheuchzerio palustris-Sphagnetum cuspidati (SS plant community associations. A total of 59 distinct fungal taxa were collected from the two bogs, with the LS association having a higher species richness and diversity than the SS association (50 taxa vs. 16 taxa and 30–40 taxa per 1000 m2 vs. 6–10 taxa per 1000 m2, respectively. Each of the two plant community associations has its own characteristic fungal taxa, with the LS association having 13 characteristic taxa and the SS association having five. Nearly two thirds of the fungal taxa are saprotrophic, mainly of Sphagnum spp., while others are mycorrhizal, mainly with Pinus spp. Most taxa were collected fewer than ten times during the study period and, hence, are considered rare and may need to be recognised for conservation programmes in this region.

  10. The Neoproterozoic-Paleozoic Arctic Margins: early stages of geodynamic evolution and plate reconstructions

    Science.gov (United States)

    Vernikovsky, V. A.; Metelkin, D. V.; Vernikovskaya, A. E.; Matushkin, N. Yu.; Lobkovsky, L. I.; Shipilov, E. V.

    2012-04-01

    Available data on the existence of Precambrian metamorphic complexes among the main structures of the Arctic led to the suggestion that a large continental mass existed between Laurentia, Baltica and Siberia - an Arctic continent, more often called Arctida (Zonenshain, Natapov, 1987). It is inferred that as an independent continental mass Arctida was formed after the breakup of Rodinia, and in general it can have a pre-Grenvillian (including Grenvillian) basement age. The breakup of this mass and the collision of its fragments with adjacent cratons led to the formation of heterochronous collisional systems. Arctida probably included the Kara, Novosibirsk, Alaska-Chukotka blocks, the blocks of northern Alaska and the submerged Lomonosov Ridge, small fragments of the Inuit fold belt in the north of Greenland and the Canadian archipelago, the structures of the Svalbard and maybe the Timan-Pechora plates. However the inner structure of this paleocontinent, the mutual configuration of the blocks and its evolution in the Neoproterozoic-Paleozoic is still a matter of discussion. The most accurate way of solving these issues is by using paleomagnetic data, but those are nonexistent for most of the defined blocks. Reliable paleomagnetic determinations for the Neoproterozoic-Paleozoic time interval we are concerned with are available only for fragments of an island arc from Central Taimyr, which are 960 m.y. old (Vernikovsky et al., 2011) and for which the paleomagnetic pole is very close to the pole of Siberia from (Pavlov et al., 2002), and of the Kara microcontinent. This includes three paleomagnetic poles for 500, 450 and 420 Ma (Metelkin et al., 2000; Metelkin et al., 2005). It is those data that made up the basis of the presented paleotectonic reconstructions along with an extensive paleomagnetic database for the cratons of Laurentia, Baltica, Siberia and Gondwana. The paleogeographic position of the cratons is corrected (within the confidence levels for the

  11. The genus Rhaponticum in East Asia

    Directory of Open Access Journals (Sweden)

    Gorovoy, P.

    2010-12-01

    Full Text Available The genus Rhaponticum in East Asia has always been a taxon for discussion. Rhaponticum carthamoides from East Siberia comprises three subspecies: carthamoides, chamarensis and orientale. Even though they differ in morphology, they do not have isolated areas. Rhaponticum satzyperovii was recently described and its author pointed out its affinity with Rh. uniflorum. Plant height, stem indumentum, and radical and stem leaf dissection were signaled as the diagnostic characters. Our present study on living and herbarium specimens of Rh. satzyperovii shows that the diagnostic characters are not consistent. The species area was also claimed to be an argument for considering Rh. satzyperovii a distinct species. This area covers the south of the Primorye Province in the Far East of Russia with some locations in the adjacent Jewish Autonomous Region and in China. In our study, the area of Rh. satzyperovii is found to be within the area of Rh. uniflorum and thereafter they turned out to have no disjunction. In East Asia, Rh. uniflorum is characterized by a wide range of morphological variability. We suggest that Rh. satzyperovii should be included within Rh. uniflorum without any taxonomic rank.El género Rhaponticum en el Este de Asia ha sido siempre un taxón discutido. Rhaponticum carthamoides del Este de Siberia incluye tres subespecies: carthamoides, chamarensis y orientale. Aunque difieren en su morfología, sus áreas no están aisladas. Rhaponticum satzyperovii fue descrito recientemente y su autor señaló su afinidad con Rh. uniflorum. Los caracteres diagnósticos fueron la altura de la planta, el indumento del tallo y las divisiones de las hojas basales y caulinares. Nuestro estudio de plantas vivas y muestras de herbario de Rh. satzyperovii muestra que los caracteres diagnósticos no son consistentes. El área de distribución también se argumentó para considerar Rh. satzyperovii una especie diferente. El área cubre el sur de la provincia de

  12. 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

  13. Insights and issues with simulating terrestrial DOC loading of Arctic river networks.

    Science.gov (United States)

    Kicklighter, David W; Hayes, Daniel J; McClelland, James W; Peterson, Bruce J; McGuire, A David; Melillo, Jerry M

    2013-12-01

    Terrestrial carbon dynamics influence the contribution of dissolved organic carbon (DOC) to river networks in addition to hydrology. In this study, we use a biogeochemical process model to simulate the lateral transfer of DOC from land to the Arctic Ocean via riverine transport. We estimate that, over the 20th century, the pan-Arctic watershed has contributed, on average, 32 Tg C/yr of DOC to river networks emptying into the Arctic Ocean with most of the DOC coming from the extensive area of boreal deciduous needle-leaved forests and forested wetlands in Eurasian watersheds. We also estimate that the rate of terrestrial DOC loading has been increasing by 0.037 Tg C/yr2 over the 20th century primarily as a result of climate-induced increases in water yield. These increases have been offset by decreases in terrestrial DOC loading caused by wildfires. Other environmental factors (CO2 fertilization, ozone pollution, atmospheric nitrogen deposition, timber harvest, agriculture) are estimated to have relatively small effects on terrestrial DOC loading to Arctic rivers. The effects of the various environmental factors on terrestrial carbon dynamics have both offset and enhanced concurrent effects on hydrology to influence terrestrial DOC loading and may be changing the relative importance of terrestrial carbon dynamics on this carbon flux. Improvements in simulating terrestrial DOC loading to pan-Arctic rivers in the future will require better information on the production and consumption of DOC within the soil profile, the transfer of DOC from land to headwater streams, the spatial distribution of precipitation and its temporal trends, carbon dynamics of larch-dominated ecosystems in eastern Siberia, and the role of industrial organic effluents on carbon budgets of rivers in western Russia. PMID:24555311

  14. Relative importance of multiple factors on terrestrial loading of DOC to Arctic river networks

    Energy Technology Data Exchange (ETDEWEB)

    Kicklighter, David W. [Ecosystem Center, The; Hayes, Daniel J [ORNL; Mcclelland, James W [University of Texas; Peterson, Bruce [Marine Biological Laboratory; Mcguire, David [University of Alaska; Melillo, Jerry [Marine Biological Laboratory

    2014-01-01

    Terrestrial carbon dynamics influence the contribution of dissolved organic carbon (DOC) to river networks in addition to controlling carbon fluxes between the land surface and the atmosphere. In this study, we use a biogeochemical process model to simulate the lateral transfer of DOC from land to the Arctic Ocean via riverine transport. We estimate that the pan-arctic watershed has contributed, on average, 32 Tg C/yr of DOC to the Arctic Ocean over the 20th century with most coming from the extensive area of boreal deciduous needle-leaved forests and forested wetlands in Eurasian watersheds. We also estimate that the rate of terrestrial DOC loading has been increasing by 0.037 Tg C/yr2 over the 20th century primarily as a result of increases in air temperatures and precipitation. These increases have been partially compensated by decreases in terrestrial DOC loading caused by wildfires. Other environmental factors (CO2 fertilization, ozone pollution, atmospheric nitrogen deposition, timber harvest, agriculture) are estimated to have relatively small effects on terrestrial DOC loading to arctic rivers. The effects of the various environmental factors on terrestrial carbon dynamics have both compensated and enhanced concurrent effects on hydrology to influence terrestrial DOC loading. Future increases in riverine DOC concentrations and export may occur from warming-induced increases in terrestrial DOC production associated with enhanced microbial metabolism and the exposure of additional organic matter from permafrost degradation along with decreases in water yield associated with warming-induced increases in evapotranspiration. Improvements in simulating terrestrial DOC loading to pan-arctic rivers in the future will require better information on the spatial distribution of precipitation and its temporal trends, carbon dynamics of larch-dominated ecosystems in eastern Siberia, and the role of industrial organic effluents on carbon budgets of rivers in western

  15. Are Recent Arctic Sea Ice Changes a Fingerprint of Greenhouse Warming?

    Science.gov (United States)

    Vavrus, S. J.

    2002-12-01

    Arctic sea ice has undergone significant reductions in thickness and extent in recent decades, leading to speculation that the ice pack is already showing signs of greenhouse warming. The decline in ice cover is not uniform across the Arctic Ocean, but instead shows a distinct spatial pattern of maximum reductions in the eastern (European) sector and minimum decreases in the western (North American) sector. This dipole spatial pattern has been dubbed the "East-West Arctic Anomaly Pattern" (EWAAP) and is consistent with recent trends in high-latitude atmospheric circulation, which in turn are driven by the well-known decrease in Arctic sea level pressure. Climate simulations using an AGCM coupled to a mixed-layer ocean (GENESIS) are presented to show that enhanced greenhouse forcing causes the model to produce the EWAAP and its associated anomalous cyclonic circulation pattern. Paleoclimate simulations of orbitally forced warm periods in the Arctic (mid-Holocene and last interglacial) show similar changes of sea ice cover and surface winds, suggesting that the recent anomalies may be a signature of warmer Arctic climates. The consistent EWAAP response to warm external forcings is caused by two dynamical mechanisms. First, the flow of Arctic sea ice in the modern climate produces ice divergence (convergence) and more (less) open water in the eastern (western) Arctic Ocean, thus favoring (hindering) melting in the eastern (western) sector under warmer conditions. Second, because warmer climates promote a decrease in Arctic sea level pressure, anomalous surface winds blow across the Arctic Ocean from Eurasia toward North America and thus enhance the spatial dipole pattern of ice coverage.

  16. Arctic River organic matter transport

    Science.gov (United States)

    Raymond, Peter; Gustafsson, Orjan; Vonk, Jorien; Spencer, Robert; McClelland, Jim

    2016-04-01

    Arctic Rivers have unique hydrology and biogeochemistry. They also have a large impact on the Arctic Ocean due to the large amount of riverine inflow and small ocean volume. With respect to organic matter, their influence is magnified by the large stores of soil carbon and distinct soil hydrology. Here we present a recap of what is known of Arctic River organic matter transport. We will present a summary of what is known of the ages and sources of Arctic River dissolved and particulate organic matter. We will also discuss the current status of what is known about changes in riverine organic matter export due to global change.

  17. 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.

  18. Cultural Dialogue Development between Russia and Siberia at the Turn of XIX–XX Centuries

    Directory of Open Access Journals (Sweden)

    Tatyana V. Gryaznukhina

    2013-01-01

    Full Text Available The article is concerned with the problems of cultural dialogue development between two regions – Central Russia and Siberia at the turn of XIX – XX centuries. The position of local intelligentsia, envisaging Siberia as big independent region, having its unique social, economic and ethnographic features is showed. Specific features of Siberian population mentality were reflected in works by local and Russian intelligentsia. The paper studies the foundations of cultural dialogue between the regions, having inequitable character, presents the position of local intelligentsia, aimed at the relative independence of Siberia development and building of intercultural relationship on egalitarian basis. The forms of intercultural dialogue are analyzed. The impact of capitals’ cultural life on Siberian culture development is showed. The role of Russian and Siberian intelligentsia in establishment and development of intercultural communications between the two regions is justified.

  19. Russian Arctic warming and ‘greening’ are closely tracked by tundra shrub willows

    Science.gov (United States)

    Forbes, B. C.; Macias Fauria, M.; Zetterberg, P.

    2009-12-01

    Growth in arctic vegetation is generally expected to increase under a warming climate, particularly among deciduous shrubs. We analyzed annual ring growth for an abundant and nearly circumpolar erect willow (Salix lanata L.) from the coastal zone of the northwest Russian Arctic (Nenets Autonomous Okrug). The resulting chronology is strongly related to summer temperature for the period 1942-2005. Remarkably high correlations occur at long distances (>1600 km) across the tundra and taiga zones of West Siberia and Eastern Europe. We also found a clear relationship with photosynthetic activity for upland vegetation at a regional scale for the period 1981-2005, confirming a parallel ‘greening’ trend reported for similarly warming North American portions of the tundra biome. The standardized growth curve suggests a significant increase in shrub willow growth over the last six decades. These findings are in line with field and remote sensing studies that have assigned a strong shrub component to the reported greening signal since the early 1980s. Furthermore, the growth trend agrees with qualitative observations by nomadic Nenets reindeer herders of recent increases in willow size in the region. The quality of the chronology as a climate proxy is exceptional. Given its wide geographic distribution and the ready preservation of wood in permafrost, S. lanata L. has great potential for extended temperature reconstructions in remote areas across the Arctic.

  20. The Arctic Circle Revisited

    CERN Document Server

    Colomo, F

    2007-01-01

    The problem of limit shapes in the six-vertex model with domain wall boundary conditions is addressed by considering a specially tailored bulk correlation function, the emptiness formation probability. A closed expression of this correlation function is given, both in terms of certain determinant and multiple integral, which allows for a systematic treatment of the limit shapes of the model for full range of values of vertex weights. Specifically, we show that for vertex weights corresponding to the free-fermion line on the phase diagram, the emptiness formation probability is related to a one-matrix model with a triple logarithmic singularity, or Triple Penner model. The saddle-point analysis of this model leads to the Arctic Circle Theorem, and its generalization to the Arctic Ellipses, known previously from domino tilings.

  1. Agrolandscape Research of Geosystems in the South of Central Siberia

    Science.gov (United States)

    Lysanova, G.; Soja, A. J.

    2012-12-01

    Minusinskaya basin, the area under research, is situated in the south of Central Siberia and is an agrarian region, which differs from another territories of Siberia. The territory provides for foodstuff not only its population but another regions as well. Nature-climate conditions favour the development of agriculture and cattle-breeding. Complex geographical study of rural lands, which is implemented by two approaches: a natural and industrial system block is necessary for rational use of agrolandscapes. Agrolandscapes are objects for rationalization of land management in agricultural regions. From our point of view application of a landscape map as a base for working out of agrolandscape map (Fig. 1a) and a map of agronatural potential of geosystems (Fig. 2), gives an opportunity to take stock of reserves of agricultural lands not only in quantitative but qualitative respects and also to determine the ways of optimal transformation of arable lands depending on nature conditions of regions and their development. Landscape maps that reflect differentiation of not only natural formations, changed by anthropogenious influence and also natural analogues, concern to a number of important tools of planning for optimal land use. The main principles of working out of typological landscape map of a medium scale aroused from targets and tasks of agrolandscape estimation of the territory [1]. The landscape map was worked out according to V.A. Nikolaev's methodology [2]: types of landscapes correlated with types of lands use, composition of cereals in rotation of crops, agro-techniques, crop capacity, climate indices, etc. Existing natural-agricultural systems are shown in the map. Their characteristics includes information about natural and agricultural blocks. Agronatural potential had been calculated by summarize estimations of its component parts. As a result of these calculations 30 arable agrolandscapes, marked out into the landscape map, were joined according to summ

  2. Novel biodiversity baselines outpace models of fish distribution in Arctic waters

    DEFF Research Database (Denmark)

    Christiansen, Jørgen Schou; Bonsdorff, Erik; Byrkjedal, Ingvar;

    2016-01-01

    cod >1000 km further north in East Greenland waters. In light of climate change, we discuss physical forcing and putative connections between the faunas of the Northeast Greenland shelf and the Barents Sea. We emphasise the importance of using real data in spread scenarios for understudied Arctic seas....

  3. Origin of freshwater and polynya water in the Arctic Ocean halocline in summer 2007

    NARCIS (Netherlands)

    Bauch, D.; Rutgers van der Loeff, M.; Andersen, N.; Torres-Valdes, S.; Bakker, K.; Abrahamsen, E.Povl

    2011-01-01

    Extremely low summer sea-ice coverage in the Arctic Ocean in 2007 allowed extensive sampling and a wide quasi-synoptic hydrographic and delta O-18 dataset could be collected in the Eurasian Basin and the Makarov Basin up to the Alpha Ridge and the East Siberian continental margin. With the aim of de

  4. Recent Trends in the Arctic Navigable Ice Season and Links to Atmospheric Circulation

    Science.gov (United States)

    Maslanik, J.; Drobot, S.

    2002-12-01

    One of the potential effects of Arctic climate warming is an increase in the navigable ice season, perhaps resulting in development of the Arctic as a major shipping route. The distance from western North American ports to Europe through the Northwest Passage (NWP) or the Northern Sea Route (NSR) is typically 20 to 60 percent shorter than travel through the Panama Canal, while travel between Europe and the Far East may be reduced by as much as three weeks compared to transport through the Suez Canal. An increase in the navigable ice season would also improve commercial opportunities within the Arctic region, such as mineral and oil exploration and tourism, which could potentially expand the economic base of Arctic residents and companies, but which would also have negative environmental impacts. Utilizing daily passive-microwave derived sea ice concentrations, trends and variability in the Arctic navigable ice season are examined from 1979 through 2001. Trend analyses suggest large increases in the length of the navigable ice season in the Kara and Barents seas, the Sea of Okhotsk, and the Beaufort Sea, with decreases in the length of the navigable ice season in the Bering Sea. Interannual variations in the navigable ice season largely are governed by fluctuations in low-frequency atmospheric circulation, although the specific annular modes affecting the length of the navigable ice season vary by region. In the Beaufort and East Siberian seas, variations in the North Atlantic Oscillation/Arctic Oscillation control the navigable ice season, while variations in the East Pacific anomaly play an important role in controlling the navigable ice season in the Kara and Barents seas. In Hudson Bay, the Canadian Arctic Archipelago, and Baffin Bay, interannual variations in the navigable ice season are strongly related to the Pacific Decadal Oscillation.

  5. 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.

  6. 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.

  7. Parameterization of tree-ring growth in Siberia

    Science.gov (United States)

    Tychkov, Ivan; Popkova, Margarita; Shishov, Vladimir; Vaganov, Eugene

    2016-04-01

    No doubt, climate-tree growth relationship is an one of the useful and interesting subject of studying in dendrochronology. It provides an information of tree growth dependency on climatic environment, but also, gives information about growth conditions and whole tree-ring growth process for long-term periods. New parameterization approach of the Vaganov-Shashkin process-based model (VS-model) is developed to described critical process linking climate variables with tree-ring formation. The approach (co-called VS-Oscilloscope) is presented as a computer software with graphical interface. As most process-based tree-ring models, VS-model's initial purpose is to describe variability of tree-ring radial growth due to variability of climatic factors, but also to determinate principal factors limiting tree-ring growth. The principal factors affecting on the growth rate of cambial cells in the VS-model are temperature, day light and soil moisture. Detailed testing of VS-Oscilloscope was done for semi-arid area of southern Siberia (Khakassian region). Significant correlations between initial tree-ring chronologies and simulated tree-ring growth curves were obtained. Direct natural observations confirm obtained simulation results including unique growth characteristic for semi-arid habitats. New results concerning formation of wide and narrow rings under different climate conditions are considered. By itself the new parameterization approach (VS-oscilloscope) is an useful instrument for better understanding of various processes in tree-ring formation. The work was supported by the Russian Science Foundation (RSF # 14-14-00219).

  8. Laurentian origin for the North Slope of Alaska: Implications for the tectonic evolution of the Arctic

    Science.gov (United States)

    Strauss, J. V.; Macdonald, F. A.; Taylor, J. F.; Repetski, John E.; McClelland, W. C.

    2013-01-01

    The composite Arctic Alaska–Chukotka terrane plays a central role in tectonic reconstructions of the Arctic. An exotic, non-Laurentian origin of Arctic Alaska–Chukotka has been proposed based on paleobiogeographic faunal affinities and various geochronological constraints from the southwestern portions of the terrane. Here, we report early Paleozoic trilobite and conodont taxa that support a Laurentian origin for the North Slope subterrane of Arctic Alaska, as well as new Neoproterozoic–Cambrian detrital zircon geochronological data, which are both consistent with a Laurentian origin and profoundly different from those derived from similar-aged strata in the southwestern subterranes of Arctic Alaska–Chukotka. The North Slope subterrane is accordingly interpreted as allochthonous with respect to northwestern Laurentia, but it most likely originated farther east along the Canadian Arctic or Atlantic margins. These data demonstrate that construction of the composite Arctic Alaska–Chukotka terrane resulted from juxtaposition of the exotic southwestern fragments of the terrane against the northern margin of Laurentia during protracted Devonian(?)–Carboniferous tectonism.

  9. Air Mass Origin in the Arctic and its Response to Future Warming

    Science.gov (United States)

    Orbe, Clara; Newman, Paul A.; Waugh, Darryn W.; Holzer, Mark; Oman, Luke; Polvani, Lorenzo M.; Li, Feng

    2014-01-01

    We present the first climatology of air mass origin in the Arctic in terms of rigorously defined air mass fractions that partition air according to where it last contacted the planetary boundary layer (PBL). Results from a present-day climate integration of the GEOSCCM general circulation model reveal that the Arctic lower troposphere below 700 mb is dominated year round by air whose last PBL contact occurred poleward of 60degN, (Arctic air, or air of Arctic origin). By comparison, approx. 63% of the Arctic troposphere above 700 mb originates in the NH midlatitude PBL, (midlatitude air). Although seasonal changes in the total fraction of midlatitude air are small, there are dramatic changes in where that air last contacted the PBL, especially above 700 mb. Specifically, during winter air in the Arctic originates preferentially over the oceans, approx. 26% in the East Pacific, and approx. 20% in the Atlantic PBL. By comparison, during summer air in the Arctic last contacted the midlatitude PBL primarily over land, overwhelmingly so in Asia (approx. 40 %) and, to a lesser extent, in North America (approx. 24%). Seasonal changes in air-mass origin are interpreted in terms of seasonal variations in the large-scale ventilation of the midlatitude boundary layer and lower troposphere, namely changes in the midlatitude tropospheric jet and associated transient eddies during winter and large scale convective motions over midlatitudes during summer.

  10. Natural Disaster Risk and Engagement in the Arctic

    Science.gov (United States)

    Eichelberger, J. C.

    2015-12-01

    The Arctic is beset with natural hazards no less than other regions of Earth, but there are some special aspects that require attention. The presence of ice leads to spring river flooding and dynamics of coastal erosion not present in warmer climates. Vast boreal forests are subject to wildfires that are huge pollution events and a positive feedback to climate change through production of CO2, other gases, and black carbon. Darkness and extreme cold that prevail for a significant portion of the year is a challenge to disaster response. Special societal aspects of the Arctic produce vulnerabilities on two scales. One is the development of infrastructure in support of growing extractive industries and Arctic shipping. Reliance on such facilities, which often lack redundancy, and on long supply lines for food and fuel from the south impedes resilience. In 1964, Alaska lost much of its infrastructure to the 9.2 magnitude earthquake and subsequent tsunamis. Today, Alaska has greater dependency on external supplies and less internal redundancy. Planning that affects vulnerability of infrastructure is often done by corporations and regulated by government agencies based outside the Arctic. The work of scientists who understood Alaska, both within and outside government, provided information to energy corporations persuading them to include expensive design measures into the Trans Alaska Pipeline for crossing an active fault and preventing thawing of permafrost. This is a success story that should not be forgotten. At the other end of the size scale are isolated off-grid and off-road remote communities with fragile power, water, and sanitation facilities. A disaster there can pose an immediate threat to health and even life. Long-term evacuation and the cost a reconstruction may mean that the community is never re-established. Where such communities are centers of indigneous culture, the culture is threatened. With the goal of identifying best practices with these

  11. Forms of Wages for Miners of Siberia in the Late XIX – Early XX Centuries

    Directory of Open Access Journals (Sweden)

    Vasiliy P. Zinovyev

    2014-03-01

    Full Text Available The article considers the question of forms of wages paid to workers in the mining industry of Siberia in the late XIX – early XX centuries. Of the two main forms of labor compensation – hourly rate and piecework pay, the latter was more corresponding to the spirit of capitalism, and it was most widespread in the mining enterprises of Siberia. The piecework pay was also the main instrument for intensifying labor productivity. This episode in the history of labor is studied on the basis of paperwork materials of mining companies and reporting documents of the mining inspectorate.

  12. Gas export potential of Russia's East: Will it match Asia-Pacific markets?

    International Nuclear Information System (INIS)

    Russia's Far East and East Siberia are emerging as new major sources of gas supplies for East Asian energy markets. Thanks to ongoing and earmarked resource and infrastructure developments in Sakhalin, Yakutia (Sakha) and Irkutsk, by around 2020 these poorly developed but naturally endowed areas of the country's East can provide between 50 and 70 Bcm/yr (5-7 Bcfd) of natural gas, including up to 10 Mt/yr of LNG, available for exports to neighbouring Pacific countries (primarily to the PRC, Japan, South Korea as well as to Taiwan and the U.S. West Coast). This can noticeably reshape today's matrix of the Asia-Pacific energy flows and even destabilize the regional gas market. (author)

  13. Impacts of Declining Arctic Sea Ice: An International Challenge

    Science.gov (United States)

    Serreze, M.

    2008-12-01

    As reported by the National Snow and Ice Data Center in late August of 2008, Arctic sea ice extent had already fallen to its second lowest level since regular monitoring began by satellite. As of this writing, we were closing in on the record minimum set in September of 2007. Summers may be free of sea ice by the year 2030. Recognition is growing that ice loss will have environmental impacts that may extend well beyond the Arctic. The Arctic Ocean will in turn become more accessible, not just to tourism and commercial shipping, but to exploitation of oil wealth at the bottom of the ocean. In recognition of growing accessibility and oil operations, the United States Coast Guard set up temporary bases this summer at Barrow and Prudhoe Bay, AK, from which they conducted operations to test their readiness and capabilities, such as for search and rescue. The Canadians have been busy showing a strong Arctic presence. In August, a German crew traversed the Northwest Passage from east to west in one of their icebreakers, the Polarstern. What are the major national and international research efforts focusing on the multifaceted problem of declining sea ice? What are the areas of intersection, and what is the state of collaboration? How could national and international collaboration be improved? This talk will review some of these issues.

  14. Black carbon in the Arctic: the underestimated role of gas flaring and residential combustion emissions

    Directory of Open Access Journals (Sweden)

    A. Stohl

    2013-09-01

    annual mean Arctic BC surface concentrations due to residential combustion by 68% when using daily emissions. A large part (93% of this systematic increase can be captured also when using monthly emissions; the increase is compensated by a decreased BC burden at lower latitudes. In a comparison with BC measurements at six Arctic stations, we find that using daily-varying residential combustion emissions and introducing gas flaring emissions leads to large improvements of the simulated Arctic BC, both in terms of mean concentration levels and simulated seasonality. Case studies based on BC and carbon monoxide (CO measurements from the Zeppelin observatory appear to confirm flaring as an important BC source that can produce pollution plumes in the Arctic with a high BC / CO enhancement ratio, as expected for this source type. BC measurements taken during a research ship cruise in the White, Barents and Kara seas north of the region with strong flaring emissions reveal very high concentrations of the order of 200–400 ng m−3. The model underestimates these concentrations substantially, which indicates that the flaring emissions (and probably also other emissions in northern Siberia are rather under- than overestimated in our emission data set. Our results suggest that it may not be "vertical transport that is too strong or scavenging rates that are too low" and "opposite biases in these processes" in the Arctic and elsewhere in current aerosol models, as suggested in a recent review article (Bond et al., Bounding the role of black carbon in the climate system: a scientific assessment, J. Geophys. Res., 2013, but missing emission sources and lacking time resolution of the emission data that are causing opposite model biases in simulated BC concentrations in the Arctic and in the mid-latitudes.

  15. Black carbon in the Arctic: the underestimated role of gas flaring and residential combustion emissions

    Science.gov (United States)

    Stohl, A.; Klimont, Z.; Eckhardt, S.; Kupiainen, K.; Shevchenko, V. P.; Kopeikin, V. M.; Novigatsky, A. N.

    2013-09-01

    BC surface concentrations due to residential combustion by 68% when using daily emissions. A large part (93%) of this systematic increase can be captured also when using monthly emissions; the increase is compensated by a decreased BC burden at lower latitudes. In a comparison with BC measurements at six Arctic stations, we find that using daily-varying residential combustion emissions and introducing gas flaring emissions leads to large improvements of the simulated Arctic BC, both in terms of mean concentration levels and simulated seasonality. Case studies based on BC and carbon monoxide (CO) measurements from the Zeppelin observatory appear to confirm flaring as an important BC source that can produce pollution plumes in the Arctic with a high BC / CO enhancement ratio, as expected for this source type. BC measurements taken during a research ship cruise in the White, Barents and Kara seas north of the region with strong flaring emissions reveal very high concentrations of the order of 200-400 ng m-3. The model underestimates these concentrations substantially, which indicates that the flaring emissions (and probably also other emissions in northern Siberia) are rather under- than overestimated in our emission data set. Our results suggest that it may not be "vertical transport that is too strong or scavenging rates that are too low" and "opposite biases in these processes" in the Arctic and elsewhere in current aerosol models, as suggested in a recent review article (Bond et al., Bounding the role of black carbon in the climate system: a scientific assessment, J. Geophys. Res., 2013), but missing emission sources and lacking time resolution of the emission data that are causing opposite model biases in simulated BC concentrations in the Arctic and in the mid-latitudes.

  16. Mining in the European Arctic

    NARCIS (Netherlands)

    van Dam, Kim; Scheepstra, Annette; Gille, Johan; Stępień, Adam; Koivurova, Timo

    2014-01-01

    The European Arctic is currently experiencing an upsurge in mining activities, but future developments will be highly sensitive to mineral price fluctuations. The EU is a major consumer and importer of Arctic raw materials. As the EU is concerned about the security of supply, it encourages domestic

  17. Influence of fire events on permafrost, Yubileynoe Gas Field, West Siberia

    Science.gov (United States)

    Grebenets, V.; Kurchatova, A. N.; Shmelev, D.; Streletskiy, D. A.

    2012-12-01

    The study area is located in the Subarctic region of Western Siberia at Nadym and Pur Rivers interfluve. The mean monthly air temperature of the coldest month is -25…-27oC and of the warmest month is 8…10oC. The mean annual air temperature is increasing at 0.03…0.06oC per year. The mean annual precipitation is 550…600 mm. The continuous permafrost up to 50-70 m thick have temperature of -1..-3oC. The study site is located 40 km west of Noviy Urengoy City. The study site is dominated by typical forest-tundra, where the cup-mossy larch-birch light forests neighbors with typical tundra, and the boreal fir-larch forest spread across minor river valleys. Ecosystems of the study area experience strong technogenic stress from the large gas-producing enterprise "Yubileinoe" which is situated nearby. A polygonal peatland with 2-2.5 m peat at the southern bank of Nashe-to Lake was disturbed by fire in July, 2005. The fire event lasted for 2 days have burned vegetation dominated by semifrutex, sedges, mosses, and underlaying peat. Following years the succession rates were rather slow. The peatland surface is elevated relative to the surrounding drained lake basin (hasyrey) and free of snow in winter. After the disturbance of the thermo-insulating layers (peat, moss and vegetation cover) the activation of frost-cracking was observed, especially strong at completely burnt areas on sandy loam. The second site of the hasyrey has experienced the fire in the middle of July, 2007. It is located within the plain watershed with drainage hollows. The Arctic birch, semifrutex and cup-mosses were dominating in the vegetation cover of hillocky tundra. The vegetation cover has experienced slow succession after the fire. In August, 2008, we found the semifrutex, sedges and cotton-grass growing sparsely between the burnt bare hillocks. The wetness of the territory increased. As a result of vegetation cover and mosses disturbance, the thermoinsulation have decreased and the frost

  18. Stable isotope ratios of atmospheric CO_{2} and CH_{4} over Siberia measured at ZOTTO

    Science.gov (United States)

    Timokhina, Anastasiya; Prokushkin, Anatily; Lavric, Jost; Heimann, Martin

    2016-04-01

    The boreal and arctic zones of Siberia housing the large amounts of carbon stored in the living biomass of forests and wetlands, as well as in soils and specifically permafrost, play a crucial role in earth's global carbon cycle. The long-term studies of greenhouse gases (GHG) concentrations are important instruments to analyze the response of these systems to climate warming. In parallel to GHG observations, the measurements of their stable isotopic composition can provide useful information for distinguishing contribution of individual GHG source to their atmospheric variations, since each source has its own isotopic signature. In this study we report first results of laboratory analyses of the CO2 and CH4 concentrations, the stable isotope ratio of δ13C-CO2, δ18O-CO2, δ13C-CH4, δD-CH4 measured in one-liter glass flasks which were obtained from 301 height of ZOTTO (Zotino Tall Tower Observatory, near 60° N, 90° E, about 20 km west of the Yenisei River) during 2008 - 2013 and 2010 - 2013 for stable isotope composition of CO2 and CH4. The magnitudes of δ13C-CO2 and δ18O-CO2 in a seasonal cycle are -1.4±0.1‰ (-7.6 - -9.0‰) and -2.2±0.2‰ (-0.1 - -2.3‰), respectively. The δ13C-CO2 seasonal pattern opposes the CO2 concentrations, with a gradual enrichment in heavy isotope occurring during May - July, reflecting its discrimination in photosynthesis, and further depletion in August - September as photosynthetic activity decreases comparatively to ecosystem respiration. Relationship between the CO2 concentrations and respective δ13C-CO2 (Keeling plot) reveals isotopic source signature for growing season (May - September) -27.3±1.4‰ and -30.4±2.5‰ for winter (January - March). The behavior of δ18O-CO2 associated with both high photosynthetic rate in the June (enrichment of atmospheric CO2 by 18O as consequence of CO2 equilibrium with "heavy" leaf water) and respiratory activity of forest floor in June - October (depletion of respired CO2 by 18O

  19. A tale of two basins: An integrated physical and biological perspective of the deep Arctic Ocean

    Science.gov (United States)

    Bluhm, B. A.; Kosobokova, K. N.; Carmack, E. C.

    2015-12-01

    This review paper integrates the current knowledge, based on available literature, on the physical and biological conditions of the Amerasian and Eurasian basins (AB, EB) of the deep Arctic Ocean (AO) in a comparative fashion. The present day (Holocene) AO is a mediterranean sea that is roughly half continental shelf and half basin and ridge complex. Even more recently it is roughly two thirds seasonally and one third perennially ice-covered, thus now exposing a portion of basin waters to sunlight and wind. Basin boundaries and submarine ridges steer circulation pathways in overlying waters and limit free exchange in deeper waters. The AO is made integral to the global ocean by the Northern Hemisphere Thermohaline Circulation (NHTC) which drives Pacific-origin water (PW) through Bering Strait into the Canada Basin, and counter-flowing Atlantic-origin water (AW) through Fram Strait and across the Barents Sea into the Nansen Basin. As a framework for biogeography within the AO, four basic, large-scale circulation systems (with L > 1000 km) are noted; these are: (1) the large scale wind-driven circulation which forces the cyclonic Trans-Polar Drift from Siberia to the Fram Strait and the anticyclonic Beaufort Gyre in the southern Canada Basin; (2) the circulation of waters that comprise the halocline complex, composed largely of waters of Pacific and Atlantic origin that are modified during passage over the Bering/Chukchi and Barents/Siberian shelves, respectively; (3) the topographically-trapped Arctic Circumpolar Boundary Current (ACBC) which carries AW cyclonically around the boundaries of the entire suite of basins, and (4) the very slow exchange of Arctic Ocean Deep Waters. Within the basin domain two basic water mass assemblies are observed, the difference between them being the absence or presence of PW sandwiched between Arctic Surface Waters (ASW) above and the AW complex below; the boundary between these domains is the Atlantic/Pacific halocline front. Both

  20. Microbiological assessment of technogenicaly disturbed forest ecosystems in Central Siberia

    Directory of Open Access Journals (Sweden)

    A. V. Bogorodskaya

    2016-04-01

    Full Text Available The state of soil microbial complexes of forest ecosystems of Central Siberia, disturbed by cutting, fires, emissions of pollutants and mining was investigated. The most appropriate indicators for early diagnosis of the condition and sustainability assessment of soils were the contents of microbial biomass, the intensity of the basal respiration and microbial metabolic quotient. Recorded time quantitative and structural-taxonomic restructuring of ecological trophic groups of microorganisms exhibited orientation of the elementary soil-biological processes and allowed detail to assess the state of soils of disturbed forest ecosystems. Successions of soil microorganisms reflected stages of plant succession after cutting. Structural and functional changes in the microbial soil complexes marked by only one-two years after cutting of coniferous forests. For the grassy stage in deciduous young stands, there was an increase in soil microbial activity that accompanied the development of the sod process. Microbiological processes were balanced and comparable to the control at the stage of closed 30-year-old stands. Post-fire recovery of the microbial soil complexes was determined by fire severity and by the properties of soils and vegetation succession. Functional activity of microbial soil complexes were recovered in one or two years after a low-intensity fires, whereas after high-intensity fires – was not recovered in eight years. Indicative responses of soil microorganisms in the sustainable impact of aggressive pollutants tundra zone of the Norilsk industrial region were registered at the functional and at the structural level. In areas of moderate and weak disturbances of vegetation, there were quantitative changes, whereas strong disturbances and constant exposure to pollutants marked structural and taxonomic adjustment of microbial soil complexes, disturbed dynamic processes of synthesis-mineralization and reduced adaptive capacity saprophytic

  1. AMAP Assessment 2013: Arctic Ocean acidification

    Science.gov (United States)

    2013-01-01

    This assessment report presents the results of the 2013 AMAP Assessment of Arctic Ocean Acidification (AOA). This is the first such assessment dealing with AOA from an Arctic-wide perspective, and complements several assessments that AMAP has delivered over the past ten years concerning the effects of climate change on Arctic ecosystems and people. The Arctic Monitoring and Assessment Programme (AMAP) is a group working under the Arctic Council. The Arctic Council Ministers have requested AMAP to: - produce integrated assessment reports on the status and trends of the conditions of the Arctic ecosystems;

  2. 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

  3. a New Japanese Project for Arctic Climate Change Research - Grene Arctic - (Invited)

    Science.gov (United States)

    Enomoto, H.

    2013-12-01

    A new Arctic Climate Change Research Project 'Rapid Change of the Arctic Climate System and its Global Influences' has started in 2011 for a five years project. GRENE-Arctic project is an initiative of Arctic study by more than 30 Japanese universities and institutes as the flame work of GRENE (Green Network of Excellence) of MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan). The GRENE-Arctic project set four strategic research targets: 1. Understanding the mechanism of warming amplification in the Arctic 2. Understanding the Arctic system for global climate and future change 3. Evaluation of the effects of Arctic change on weather in Japan, marine ecosystems and fisheries 4. Prediction of sea Ice distribution and Arctic sea routes This project aims to realize the strategic research targets by executing following studies: -Improvement of coupled general circulation models based on validations of the Arctic climate reproducibility and on mechanism analyses of the Arctic climate change and variability -The role of Arctic cryosphere in the global change -Change in terrestrial ecosystem of pan-Arctic and its effect on climate -Studies on greenhouse gas cycles in the Arctic and their responses to climate change -Atmospheric studies on Arctic change and its global impacts -Ecosystem studies of the Arctic ocean declining Sea ice -Projection of Arctic Sea ice responding to availability of Arctic sea route (* ** ***) *Changes in the Arctic ocean and mechanisms on catastrophic reduction of Arctic sea ice cover **Coordinated observational and modeling studies on the basic structure and variability of the Arctic sea ice-ocean system ***Sea ice prediction and construction of ice navigation support system for the Arctic sea route. Although GRENE Arctic project aims to product scientific contribution in a concentrated program during 2011-2016, Japanese Arctic research community established Japan Consortium for Arctic Environmental Research (JCAR) in May

  4. Chronology of Holocene climate and vegetation changes and their connection to cultural dynamics in Southern Siberia

    NARCIS (Netherlands)

    V.G. Dirksen; B. van Geel; M.A. Koulkova; G.I. Zaitseva; A.A. Sementsov; E.M. Scott; G.T. Cook; J. van der Plicht; L.M. Lebedeva; N.D. Bourova; N.A. Bokovenko

    2007-01-01

    Two sediment sequences from Big Kyzykul Lake and the Shushenskoe paleolake in the Minusinsk depression, Southern Siberia, were studied by pollen, microfossil, and geochemical analyses, as well as radiocarbon dating. The records indicate the persistence of an arid period between ~11.7-7.6 cal kyr BP,

  5. Chronology of holocene climate and vegetation changes and their connection to cultural dynamics in Southern Siberia

    NARCIS (Netherlands)

    Dirksen, V. G.; van Geel, B.; Koulkova, M. A.; Zaitseva, G. I.; Sementsov, A. A.; Scott, E. M.; Cook, G. T.; van der Plicht, J.; Lebedeva, L. M.; Bourova, N. D.; Bokovenko, N. A.

    2007-01-01

    Two sediment sequences from Big Kyzykul Lake and the Shushenskoe paleolake in the Minusinsk depression, Southern Siberia, were studied by pollen, microfossil, and geochemical analyses, as well as radiocarbon dating. The records indicate the persistence of an and period between similar to 11.7-7.6 ca

  6. Crustal and upper mantle structure of Siberia from teleseismic receiver functions

    DEFF Research Database (Denmark)

    Soliman, Mohammad Youssof Ahmad; Thybo, Hans; Artemieva, Irina;

    2015-01-01

    -frequency P-RF component as it has about an order of magnitude better resolution than S-RF. We find no indication for significant crustal anisotropy in the cratonic areas of Siberia. The preliminary crustal thickness results from the Hk stacking and from the inversion approach agree with a previous study...

  7. Growth of Little Stint Calidris minuta chicks on the Taimyr Peninsula, Siberia

    NARCIS (Netherlands)

    Schekkerman, H; Nehls, G; Hotker, H; Tomkovich, PS; Kania, W; Chylarecki, P; Soloviev, M; Van Roomen, M

    1998-01-01

    Growth of mass and linear body dimensions (bill, tarsus and wing length) was studied in the Little Stint Calidris minuta at several locations on the Taimyr Peninsula, Siberia (73 degrees-76 degrees N) in 1983-94. Little Stints fledged at near-adult body mass, at 15 days of age. Growth followed an S-

  8. Teaching Soil Science and Ecology in West Siberia: 17 Years of Field Courses

    Science.gov (United States)

    Siewert, Christian; Barsukov, Pavel; Demyan, Scott; Babenko, Andrey; Lashchinsky, Nikolay; Smolentseva, Elena

    2014-01-01

    Since 1995, soil-ecological field courses across climatic zones in West Siberia have been organized by scientists from Russia and Germany to meet growing demands for better land use practices. They are focused on virgin landscapes and soils undisturbed by anthropogenic influences to facilitate the learning processes by excluding concealing changes…

  9. Anatomy, death, and preservation of a woolly mammoth (Mammuthus primigenius) calf, Yamal Peninsula, northwest Siberia

    NARCIS (Netherlands)

    Fisher, Daniel C.; Tikhonov, Alexei N.; Kosintsev, Pavel A.; Rountrey, Adam N.; Buigues, Bernard; van der Plicht, Johannes

    2012-01-01

    A well-preserved woolly mammoth calf found in northwest Siberia offers unique opportunities to investigate mammoth anatomy, behavior, life history and taphonomy. Analysis of the fluvial setting where the specimen was found suggests it was derived from eroding bluffs during ice-out flooding in June 2

  10. Fire Impact on Surface Fuels and Carbon Emissions in Scots pine Logged Sites of Siberia

    Science.gov (United States)

    Ivanova, G. A.; Kukavskaya, E. A.; Bogorodskaya, A. V.; Ivanov, V. A.; Zhila, S. V.; Conard, S. G.

    2012-04-01

    Forest fire and large-scale forest harvesting are the two major disturbances in the Russian boreal forests. Non-recovered logged sites total about a million hectares. Logged sites are characterized by higher fire hazard than forest sites due great amounts of logging slash, which dries out much more rapidly compared to understory fuels. Moreover, most logging sites can be easily accessed by local population. Both legal and illegal logging are also increasing rapidly in many forest areas of Siberia. Fire effects on forest overstory, subcanopy woody layer, and ground vegetation biomass were estimated on logged vs. unlogged sites in the Central Siberia region in 2009-2012 as a part of the project "The Influence of Changing Forestry Practices on the Effects of Wildfire and on Interactions Between Fire and Changing Climate in Central Siberia" supported by NASA (NEESPI). Dead down woody fuels are significantly less at unburned/logged area of dry southern regions compared to more humid northern regions. Fuel consumption was typically less in spring fires than during summer fires. Fire-caused carbon emissions on logged sites appeared to be twice that on unlogged sites. Soil respiration is less at logged areas compared to undisturbed forest. After fire soil respiration decreases both at logged and unlogged areas. arbon emissions from fire and post-fire ecosystem damage on logged sites are expected to increase under changing climate conditions and as a result of anticipated increases in future forest harvesting in Siberia.

  11. SIRS NEESPI megaproject on land - atmosphere processes in Siberia: results and perspectives

    Science.gov (United States)

    Gordov, E. P.; Kabanov, M. V.; Lykosov, V. N.; Vaganov, E. A.

    2009-04-01

    The Siberia Integrated Regional Study (SIRS, http://sirs.scert.ru/en/) is the Siberia-focused NEESPI Mega-Project. SIRS is developed in line with Earth System Science Program (ESSP) approach in cooperation of Russian Academy of Science (Siberian Branch) specialists with their European, American and Asian partners/counterparts and is aimed at coordination of multidisciplinary and "distributed" teams of specialists carrying out different scale projects on Siberia environment dynamics. Currently SIRS is supervised by the Russian National Committee for IGBP and managed by its Siberian Branch. Reported are recent results of investigations of the two major Siberian ecosystems dynamics, which are boreal forests and wetlands, with special emphasis on their role in the carbon cycle as well as results of climatic modeling for the region under study and first elements of the SIRS information-computational infrastructure forming glue for relevant multidisciplinary research. Among those are: recent results obtained at the Zotino Tall Tower Observation Facility; analysis of carbon balance between СО2 emission and accumulation based on ground observations performed at the Great Vasyugan Bog, recent development in high resolution regional climate modeling and new elements of the SIRS information-computational infrastructure. New SB RAS initiatives aimed at organization across Siberia a set of environmental observatories to monitor regional ecosystems and climate dynamics with special emphasis upon desertification and permafrost thawing processes and synchronized development of distributed facilities supporting obtained data storage and delivery are described in details. Scientific plans relying upon these developments are discussed as well.

  12. Molecular and serological studies on the recent seal virus epizootics in Europe and Siberia.

    NARCIS (Netherlands)

    T. Barrett (Thomas); J. Crowther; A.D.M.E. Osterhaus (Ab); S.M. Subbarao; J. Groen (Jan); L. Haas; L.V. Mamaev; A.M. Titenko; I.K.G. Visser (Ilona); C.J. Bostock

    1992-01-01

    textabstractThe virus epizootics which occurred in seals in both Europe and Siberia during 1987/1988 were caused by two different morbilliviruses, referred to as phocid distemper virus (PDV) 1 and 2, respectively. Molecular and serological studies have shown that the European virus is quite distinct

  13. Arctic charr farming

    OpenAIRE

    Brännäs, Eva; Larsson, Stefan; Saether, Björn Steinar; Siikavuopio, Sten Ivar; Thorarensen, Helgi; Sigurgeirsson, Ólafur; Jeuthe, Henrik

    2011-01-01

    The Arctic charr (Salvelinus alpinus L.) is a holarctic salmonid fish species with both landlocked and anadromous populations. In Scandinavia it is mainly found in the mountain area, but it also appears in deep and large lake further south, i.e. in the Alps. It is the northernmost freshwater fish and A. charr is generally regarded as the most cold-adapted freshwater fish. A. charr has been commercially farmed since the early 90ths and today, the total production is 3000, 2300 and 700 tonnes/y...

  14. Research with Arctic peoples

    DEFF Research Database (Denmark)

    Smith, H Sally; Bjerregaard, Peter; Chan, Hing Man;

    2006-01-01

    entitled "Research with Arctic Peoples: Unique Research Opportunities in Heart, Lung, Blood and Sleep Disorders". The meeting was international in scope with investigators from Greenland, Iceland and Russia, as well as Canada and the United States. Multiple health agencies from Canada and the United States...... sent representatives. Also attending were representatives from the International Union for Circumpolar Health (IUCH) and the National Indian Health Board. The working group developed a set of ten recommendations related to research opportunities in heart, lung, blood and sleep disorders; obstacles...

  15. Key Findings of the AMAP 2015 Assessment on Black Carbon and Tropospheric Ozone as Arctic Climate Forcers

    Science.gov (United States)

    Quinn, P.

    2015-12-01

    The Arctic Monitoring and Assessment Programme (AMAP) established an Expert Group on Short-Lived Climate Forcers (SLCFs) in 2009 with the goal of reviewing the state of science surrounding SLCFs in the Arctic and recommending science tasks to improve the state of knowledge and its application to policy-making. In 2011, the result of the Expert Group's work was published in a technical report entitled The Impact of Black Carbon on Arctic Climate (AMAP, 2011). That report focused entirely on black carbon (BC) and co-emitted organic carbon (OC). The SLCFs Expert Group then expanded its scope to include all species co-emitted with BC as well as tropospheric ozone. An assessment report, entitled Black Carbon and Tropospheric Ozone as Arctic Climate Forcers, was published in 2015. The assessment includes summaries of measurement methods and emissions inventories of SLCFs, atmospheric transport of SLCFs to and within the Arctic, modeling methods for estimating the impact of SLCFs on Arctic climate, model-measurement inter-comparisons, trends in concentrations of SLCFs in the Arctic, and a literature review of Arctic radiative forcing and climate response. In addition, three Chemistry Climate Models and five Chemistry Transport Models were used to calculate Arctic burdens of SLCFs and precursors species, radiative forcing, and Arctic temperature response to the forcing. Radiative forcing was calculated for the direct atmospheric effect of BC, BC-snow/ice effect, and cloud indirect effects. Forcing and temperature response associated with different source sectors (Domestic, Energy+Industry+Waste, Transport, Agricultural waste burning, Forest fires, and Flaring) and source regions (United States, Canada, Russia, Nordic Countries, Rest of Europe, East and South Asia, Arctic, mid-latitudes, tropics, southern hemisphere) were calculated. To enable an evaluation of the cost-effectiveness of regional emission mitigation options, the normalized impacts (i.e., impacts per unit

  16. State of the Arctic Environment

    International Nuclear Information System (INIS)

    The Arctic environment, covering about 21 million km2, is in this connection regarded as the area north of the Arctic Circle. General biological and physical features of the terrestrial and freshwater environments of the Arctic are briefly described, but most effort is put into a description of the marine part which constitutes about two-thirds of the total Arctic environment. General oceanography and morphological characteristics are included; e.g. that the continental shelf surrounding the Arctic deep water basins covers approximately 36% of the surface areas of Arctic waters, but contains only 2% of the total water masses. Blowout accident may release thousands of tons of oil per day and last for months. They occur statistically very seldom, but the magnitude underlines the necessity of an efficient oil spill contingency as well as sound safety and quality assurance procedures. Contingency plans should be coordinated and regularly evaluated through simulated and practical tests of performance. Arctic conditions demand alternative measures compared to those otherwise used for oil spill prevention and clean-up. New concepts or optimization of existing mechanical equipment is necessary. Chemical and thermal methods should be evaluated for efficiency and possible environmental effects. Both due to regular discharges of oil contaminated drilled cuttings and the possibility of a blowout or other spills, drilling operations in biological sensitive areas may be regulated to take place only during the less sensitive parts of the year. 122 refs., 8 figs., 8 tabs

  17. Environmental contaminants and human health in the Canadian Arctic.

    Science.gov (United States)

    Donaldson, S G; Van Oostdam, J; Tikhonov, C; Feeley, M; Armstrong, B; Ayotte, P; Boucher, O; Bowers, W; Chan, L; Dallaire, F; Dallaire, R; Dewailly, E; Edwards, J; Egeland, G M; Fontaine, J; Furgal, C; Leech, T; Loring, E; Muckle, G; Nancarrow, T; Pereg, D; Plusquellec, P; Potyrala, M; Receveur, O; Shearer, R G

    2010-10-15

    The third Canadian Arctic Human Health Assessment conducted under the Canadian Northern Contaminants Program (NCP), in association with the circumpolar Arctic Monitoring and Assessment Programme (AMAP), addresses concerns about possible adverse health effects in individuals exposed to environmental contaminants through a diet containing country foods. The objectives here are to: 1) provide data on changes in human contaminant concentrations and exposure among Canadian Arctic peoples; 2) identify new contaminants of concern; 3) discuss possible health effects; 4) outline risk communication about contaminants in country food; and 5) identify knowledge gaps for future contaminant research and monitoring. The nutritional and cultural benefits of country foods are substantial; however, some dietary studies suggest declines in the amount of country foods being consumed. Significant declines were found for most contaminants in maternal blood over the last 10 years within all three Arctic regions studied. Inuit continue to have the highest levels of almost all persistent organic pollutants (POPs) and metals among the ethnic groups studied. A greater proportion of people in the East exceed Health Canada's guidelines for PCBs and mercury, although the proportion of mothers exceeding these guidelines has decreased since the previous assessment. Further monitoring and research are required to assess trends and health effects of emerging contaminants. Infant development studies have shown possible subtle effects of prenatal exposure to heavy metals and some POPs on immune system function and neurodevelopment. New data suggest important beneficial effects on brain development for Inuit infants from some country food nutrients. The most successful risk communication processes balance the risks and benefits of a diet of country food through input from a variety of regional experts and the community, to incorporate the many socio-cultural and economic factors to arrive at a risk

  18. Changing black carbon transport to the Arctic from present day to the end of 21st century

    Science.gov (United States)

    Jiao, Chaoyi; Flanner, Mark G.

    2016-05-01

    Here we explore how climate warming under the Representative Concentration Pathway 8.5 (RCP8.5) impacts Arctic aerosol distributions via changes in atmospheric transport and removal processes. We modify the bulk aerosol module in the Community Atmosphere Model to track distributions and fluxes of 200 black carbon-like tracers emitted from different locations, and we conduct idealized experiments with and without active aerosol deposition. Changing wind patterns, studied in isolation, cause the Arctic burdens of tracers emitted from East Asia and West Europe during winter to increase about 20% by the end of the century while decreasing the Arctic burdens of North American emissions by about 30%. These changes are caused by an altered winter polar dome structure that results from Arctic amplification and inhomogeneous sea ice loss and surface warming, both of which are enhanced in the Chukchi Sea region. The resulting geostrophic wind favors Arctic transport of East Asian emissions while inhibiting poleward transport of North American emissions. When active deposition is also considered, however, Arctic burdens of emissions from northern midlatitudes show near-universal decline. This is a consequence of increased precipitation and wet removal, particularly within the Arctic, leading to decreased Arctic residence time. Simulations with present-day emissions of black carbon indicate a 13.6% reduction in the Arctic annual mean burden by the end of the 21st century, due to warming-induced transport and deposition changes, while simulations with changing climate and emissions under RCP8.5 show a 61.0% reduction.

  19. River Runoff Sensitivity in Eastern Siberia to Global Climate Warming

    Science.gov (United States)

    Georgiadi, A. G.; Milyukova, I. P.; Kashutina, E.

    2008-12-01

    During several last decades significant climate warming is observed in permafrost regions of Eastern Siberia. These changes include rise of air temperature as well as precipitation. Changes in regional climate are accompanied with river runoff changes. The analysis of the data shows that in the past 25 years, the largest contribution to the annual river runoff increase in the lower reaches of the Lena (Kyusyur) is made (in descending order) by the Lena river watershed (above Tabaga), the Aldan river (Okhotsky Perevoz), and the Vilyui river (Khatyryk-Khomo). The similar relation is also retained in the case of flood, with the seasonal river runoff of the Vilyui river being slightly decreased. Completely different relations are noted in winter, when a substantial river runoff increase is recorded in the lower reaches of the Lena river. In this case the major contribution to the winter river runoff increase in the Lena outlet is made by the winter river runoff increase on the Vilyui river. Unlike the above cases, the summer-fall river runoff in the lower reaches of the Lena river tends to decrease, which is similar to the trend exhibited by the Vilyui river. At the same time, the river runoff of the Lena (Tabaga) and Aldan (Verkhoyansky Perevoz) rivers increase. According to the results of hydrological modeling the expected anthropogenic climate warming in XXI century can bring more significant river runoff increase in the Lena river basin as compared with the recent one. Hydrological responses to climate warming have been evaluated for the plain part of the Lena river basin basing on a macroscale hydrological model featuring simplified description of processes developed in Institute of Geography of the Russian Academy of Sciences. Two atmosphere-ocean global circulation models included in the IPCC (ECHAM4/OPY3 and GFDL-R30) were used as scenarios of future global climate. According to the results of hydrological modeling the expected anthropogenic climate warming in

  20. Using the physical decomposition method to study the effects of Arctic factors on wintertime temperatures in the Northern Hemisphere and China

    Institute of Scientific and Technical Information of China (English)

    SUI Cuijuan; ZHANG Zhanhai; CAI Yi; WU Huiding

    2014-01-01

    The physical decomposition method separates atmospheric variables into four parts, correlating each with solar radiation, land–sea distribution, and inter-annual and seasonal internal forcing, strengthening the anomaly signal and increasing the correlation between variables. This method was applied to the reanalysis data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), to study the effects of Arctic factors (Arctic oscillation (AO) and Arctic polar vortex) on wintertime temperatures in the Northern Hemisphere and China. It was found that AO effects on zonal average temperature disturbance could persist for 1 month. In the AO negative phase in wintertime, the temperatures are lower in the mid–high latitudes than in normal years, but higher in low latitudes. When the polar vortex area is bigger, the zonal average temperature is lower at 50°N. Inlfuenced mainly by meridional circulation enhancement, cold air lfows from high to low latitudes;thus, the temperatures in Continental Europe and the North American continent exhibit an antiphase seesaw relationship. When the AO is in negative phase and the Arctic polar vortex larger, the temperature is lower in Siberia, but higher in Greenland and the Bering Strait. Inlfuenced by westerly troughs and ridges, the polar air disperses mainly along the tracks of atmospheric activity centers. The AO index can be considered a predictor of wintertime temperature in China. When the AO is in negative phase or the Asian polar vortex is intensiifed, temperatures in Northeast China and Inner Mongolia are lower, because under the inlfuence of the Siberia High and northeast cold vortex, the cold air lfows southwards.

  1. Late Pleistocene Variations in the Water Current and Ice Rafting Transportations of Organic Matter in the Central Arctic Ocean (ACEX Hole M0004C)

    Science.gov (United States)

    Yamamoto, M.; Sugisaki, S.; Sakamoto, T.

    2006-12-01

    Little is known about the source of organic matter and the response of sedimentary organic matter composition to glacial-interglacial changes in the central Arctic Ocean. Here we have generated late Pleistocene records of biomarkers and ice rafted debris (IRD) from IODP-Arctic Coring Expedition (ACEX) Hole M0004C to understand the glacial-interglacial changes of mass transportation in the Arctic Ocean. Major biomarkers detected in Hole M0004C were long-chain n-alkanes, n-fatty acids and n-alkan-1-ols, derived from fresh higher plants, and gem-alkanes (branched aliphatic alkanes with a quaternary substituted carbon atom), derived from unknown source. Minor biomarkers were oleanenes of angiosperm origin, unsaturated fatty acids, bacteria-derived anteiso- and iso-fatty acids, various hydroxy acids, formed by hydroxylation of n-fatty acids by aerobic bacteria, cholesterol and sitosterol, and hopanes, formed by diagenetic alteration of bacterial biohopanoids. There was no concrete evidence for in situ production of phytoplanktons. The concentrations of these biomarkers varied with IRD number variation. During periods of abundant IRD, diagenetic hopanes were abundant, suggesting that clastic materials were supplied by ice rafting. During periods of scarce IRD, the other biomarkers such as long-chain compounds were abundant, suggesting that the riverine discharge was enhanced. The IRD and biomarker variations were synchronized with the eastward expansion of the Fennoscandinavian Ice Sheet to northen Siberia, suggesting that the ice cover of northen Siberia is critical in switching mass transportation mechanisms in the Arctic Ocean.

  2. SCICEX: Submarine Arctic Science Program

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Submarine Arctic Science Program, SCICEX, is a federal interagency collaboration among the operational Navy, research agencies, and the marine research...

  3. Development of arctic wind technology

    Energy Technology Data Exchange (ETDEWEB)

    Holttinen, H.; Marjaniemi, M.; Antikainen, P. [VTT Energy, Espoo (Finland)

    1998-10-01

    The climatic conditions of Lapland set special technical requirements for wind power production. The most difficult problem regarding wind power production in arctic regions is the build-up of hard and rime ice on structures of the machine

  4. 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 betwe...

  5. The Arctic as a test case for an assessment of climate impacts on national security.

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Mark A.; Zak, Bernard Daniel; Backus, George A.; Ivey, Mark D.; Boslough, Mark Bruce Elrick

    2008-11-01

    The Arctic region is rapidly changing in a way that will affect the rest of the world. Parts of Alaska, western Canada, and Siberia are currently warming at twice the global rate. This warming trend is accelerating permafrost deterioration, coastal erosion, snow and ice loss, and other changes that are a direct consequence of climate change. Climatologists have long understood that changes in the Arctic would be faster and more intense than elsewhere on the planet, but the degree and speed of the changes were underestimated compared to recent observations. Policy makers have not yet had time to examine the latest evidence or appreciate the nature of the consequences. Thus, the abruptness and severity of an unfolding Arctic climate crisis has not been incorporated into long-range planning. The purpose of this report is to briefly review the physical basis for global climate change and Arctic amplification, summarize the ongoing observations, discuss the potential consequences, explain the need for an objective risk assessment, develop scenarios for future change, review existing modeling capabilities and the need for better regional models, and finally to make recommendations for Sandia's future role in preparing our leaders to deal with impacts of Arctic climate change on national security. Accurate and credible regional-scale climate models are still several years in the future, and those models are essential for estimating climate impacts around the globe. This study demonstrates how a scenario-based method may be used to give insights into climate impacts on a regional scale and possible mitigation. Because of our experience in the Arctic and widespread recognition of the Arctic's importance in the Earth climate system we chose the Arctic as a test case for an assessment of climate impacts on national security. Sandia can make a swift and significant contribution by applying modeling and simulation tools with internal collaborations as well as with

  6. New and rare findings of lignicolous lichen species for the Southern Siberia from the Baikal nature reserve

    Directory of Open Access Journals (Sweden)

    I. N. Urbanavichene

    2015-05-01

    Full Text Available Based on field trips between 2009–2014, rare and noteworthy lichens from the Baikal Nature Reserve (Baikal nature reserve, Khamar-Daban ridge are described. These are mostly lignicolous lichens growing on wood and bark of Abies sibirica and Pinus sibirica, such as Absconditella lignicola, Strangospora moriformis, Trapeliopsis gelatinosa, T. viridescens. Trapeliopsis pseudogranulosa is new for Siberia, Lepraria jackii – new for South Siberia.

  7. Pristine Arctic: Background mapping of PAHs, PAH metabolites and inorganic trace elements in the North-Atlantic Arctic and sub-Arctic coastal environment

    Energy Technology Data Exchange (ETDEWEB)

    Jörundsdóttir, Hrönn Ólína, E-mail: hronn.o.jorundsdottir@matis.is [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Jensen, Sophie [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Hylland, Ketil; Holth, Tor Fredrik [Department of Biosciences, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo (Norway); Gunnlaugsdóttir, Helga [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Svavarsson, Jörundur [University of Iceland, Department of Life and Environmental Sciences, Askja - Natural Science Building, Sturlugata 7, 101 Reykjavík (Iceland); Ólafsdóttir, Ásdís [The University of Iceland´s Research Centre in Sudurnes, Gardvegi 1, 245 Sandgerdi (Iceland); El-Taliawy, Haitham [Matis Ltd., Icelandic Food and Biotech R and D, Vinlandsleid 12, 113 Reykjavik (Iceland); Rigét, Frank; Strand, Jakob [Department of Bioscience, Arctic Research Centre, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde (Denmark); Nyberg, Elisabeth; Bignert, Anders [Swedish Museum of Natural History, P.O. Box 50007, 104 05 Stockholm (Sweden); Hoydal, Katrin S. [The Faroese Environment Agency, Traðagøta 38, P.O. Box 2048, FO-165 Argir, the Faroe Islands (Faroe Islands); Halldórsson, Halldór Pálmar [The University of Iceland´s Research Centre in Sudurnes, Gardvegi 1, 245 Sandgerdi (Iceland)

    2014-09-15

    As the ice cap of the Arctic diminishes due to global warming, the polar sailing route will be open larger parts of the year. These changes are likely to increase the pollution load on the pristine Arctic due to large vessel traffic from specific contaminant groups, such as polycyclic aromatic hydrocarbons (PAHs). A well-documented baseline for PAH concentrations in the biota in the remote regions of the Nordic Seas and the sub-Arctic is currently limited, but will be vital in order to assess future changes in PAH contamination in the region. Blue mussels (Mytilus edulis) were collected from remote sites in Greenland, Iceland, the Faroe Islands, Norway and Sweden as well as from urban sites in the same countries for comparison. Cod (Gadus morhua) was caught north of Iceland and along the Norwegian coast. Sixteen priority PAH congeners and the inorganic trace elements arsenic, cadmium, mercury and lead were analysed in the blue mussel samples as well as PAH metabolites in cod bile. Σ{sub 16}PAHs ranged from 28 ng/g dry weight (d.w.) (Álftafjörður, NW Iceland) to 480 ng/g d.w. (Ísafjörður, NW Iceland). Mussel samples from Mjóifjörður, East Iceland and Maarmorilik, West Greenland, contained elevated levels of Σ{sub 16}PAHs, 370 and 280 ng/g d.w., respectively. Levels of inorganic trace elements varied with highest levels of arsenic in mussels from Ísafjörður, Iceland (79 ng/g d.w.), cadmium in mussels from Mjóifjörður, Iceland (4.3 ng/g d.w.), mercury in mussels from Sørenfjorden, Norway (0.23 ng/g d.w.) and lead in mussels from Maarmorilik, Greenland (21 ng/g d.w.). 1-OH-pyrene was only found above limits of quantification (0.5 ng/mL) in samples from the Norwegian coast, ranging between 44 and 140 ng/ml bile. Generally, PAH levels were low in mussels from the remote sites investigated in the study, which indicates limited current effect on the environment. - Highlights: • Low levels of PAHs in blue mussels from remote areas of the Arctic. • Low

  8. Gazprom has ambitions in the Far East. Russia's natural gas producer looks towards Japan; Gazprom hegt Ambitionen in Fernost. Russischer Erdgasfoerderer blickt nach Japan

    Energy Technology Data Exchange (ETDEWEB)

    Bollinger-Kanne, Josephine

    2012-11-12

    There are enormous reserves of natural gas in the Russian iciness in the far north of Siberia. The gas company Gazprom (Moscow, Russia) transports these stocks via a pipeline and by ship to Europe and to the Far East. The reactor accident at Fukushima and the subsequent shutdown of all nuclear power plants in Japan in May 2012 inspired the Russian ambitions to establish itself as a key supplier of energy in the Pacific.

  9. Permafrost evolution under the influence of long-term climate fluctuations and glacio-eustatic sea-level variation: region of Laptev and East Siberian seas, Russia

    OpenAIRE

    Romanivskii, N. N.; Hubberten, Hans-Wolfgang; Romanovsky, V. E.; Kholodov, A. L.

    2003-01-01

    Results of a five-year investigation of permafrost and gas-hydrate stability zone evolution on the Laptev and East Siberia Seas shelf are presented. For investigation of permafrost and gas hydrate stability zone (GHSZ) evolution during the Middle Pleistocene– Holocene (last 400 ka), a palaeo-geographic scenario and numerical model were developed. The model takes into consideration the duration of permafrost agradation and degradation, existence of permafrost temperature zonality, different...

  10. A positive test of East Antarctica-Laurentia juxtaposition within the Rodinia supercontinent.

    Science.gov (United States)

    Goodge, J W; Vervoort, J D; Fanning, C M; Brecke, D M; Farmer, G L; Williams, I S; Myrow, P M; DePaolo, D J

    2008-07-11

    The positions of Laurentia and other landmasses in the Precambrian supercontinent of Rodinia are controversial. Although geological and isotopic data support an East Antarctic fit with western Laurentia, alternative reconstructions favor the juxtaposition of Australia, Siberia, or South China. New geologic, age, and isotopic data provide a positive test of the juxtaposition with East Antarctica: Neodymium isotopes of Neoproterozoic rift-margin strata are similar; hafnium isotopes of approximately 1.4-billion-year-old Antarctic-margin detrital zircons match those in Laurentian granites of similar age; and a glacial clast of A-type granite has a uraniun-lead zircon age of approximately 1440 million years, an epsilon-hafnium initial value of +7, and an epsilon-neodymium initial value of +4. These tracers indicate the presence of granites in East Antarctica having the same age, geochemical properties, and isotopic signatures as the distinctive granites in Laurentia.

  11. Falling phytoplankton: altered access to the photic zone over 60 years of warming in Lake Baikal, Siberia

    Science.gov (United States)

    Hampton, S. E.; Izmest'eva, L. R.; Moore, M.; Katz, S. L.

    2011-12-01

    Vertical stratification of aquatic ecosystems can be strongly reinforced by long-term warming, altering access to suitable habitat differentially across plankton taxa. Surface waters in the world's most voluminous freshwater lake - Lake Baikal in Siberia - are warming at an average rate of 2.01°C century-1, with more dramatic warming in the summer (3.78°C century-1). This long-term warming trend occurs within seasonal cycles of freezing and thawing, and against the larger backdrop of shorter-term climate dynamics, such as those associated with the Pacific Decadal Oscillation and Arctic Oscillation, with which shifting Siberian weather patterns affect the timing of seasonal changes (e.g., stratification) at the lake. While the increasing temperature difference between surface and deeper waters implies stronger stratification in the summer in general, the available long-term temperature data are not sufficiently fine-scaled across depth to further resolve stratification patterns. However, analysis of long-term vertical phytoplankton distributions may give perspectives on the dynamics of the physical environment that plankton experience. For example, many of Lake Baikal's endemic, cold-adapted phytoplankton species are large and heavy diatoms that require strong mixing to remain suspended, a process that is suppressed by stronger summer stratification. Observed vertical patterns of algal distribution are consistent with the predictions of increased warming and intensified stratification with diatoms present in summer increasingly sinking far beyond the photic zone. Specifically, the average depth of diatoms in August, the most reliably stratified month at Lake Baikal, has increased from depths roughly aligned with photic zone (0.1% light penetration) limits (ca. 40 m) in the 1970s to average depths approximately 48 m below the photic zone by the end of the century. Concurrently, smaller motile algae such as cryptomonads have maintained or increased their presence in

  12. Siberia, the wandering northern terrane, and its changing geography through the Palaeozoic

    Science.gov (United States)

    Cocks, L. Robin M.; Torsvik, Trond H.

    2007-05-01

    The old terrane of Siberia occupied a very substantial area in the centre of today's political Siberia and also adjacent areas of Mongolia, eastern Kazakhstan, and northwestern China. Siberia's location within the Early Neoproterozoic Rodinia Superterrane is contentious (since few if any reliable palaeomagnetic data exist between about 1.0 Ga and 540 Ma), but Siberia probably became independent during the breakup of Rodinia soon after 800 Ma and continued to be so until very near the end of the Palaeozoic, when it became an integral part of the Pangea Supercontinent. The boundaries of the cratonic core of the Siberian Terrane (including the Patom area) are briefly described, together with summaries of some of the geologically complex surrounding areas, and it is concluded that all of the Palaeozoic underlying the West Siberian Basin (including the Ob-Saisan Surgut area), Tomsk Terrane, Altai-Sayan Terranes (including Salair, Kuznetsk Alatau, Batenov, Kobdin and West Sayan), Ertix Terrane, Barguzin Terrane, Tuva-Mongol Terrane, Central Mongolia Terrane Assemblage, Gobi Altai and Mandalovoo Terranes, Okhotsk Terrane and much of the Verkhoyansk-Kolyma region all formed parts of peri-Siberia, and thus rotated with the main Siberian Craton as those areas were progressively accreted to the main Siberian Terrane at various times during the latest Neoproterozoic and Palaeozoic. The Ertix Terrane is a new term combining what has been termed the "Altay Terrane" or "NE Xinjiang" area of China, and the Baytag, Baaran and Bidz terranes of Mongolia. The Silurian Tuvaella brachiopod fauna is restricted only to today's southern parts of peri-Siberia. Thus, allowing for subsequent rotation, the fauna occurs only in the N of the Siberian Terrane, and, as well as being a helpful indicator of what marginal terranes made up peri-Siberia, is distinctive as being the only Silurian fauna known from northern higher latitudes globally. In contrast, the other terranes adjacent to peri-Siberia

  13. 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

    The ISO-ARC project aims at documenting the Arctic atmospheric hydrological cycle, by assessing the imprint of the marine boundary conditions (e.g. temperature variations, circulation changes, or meltwater input) to the isotopic composition of the atmospheric water cycle (H218O and HDO) with a focus on North Atlantic and Arctic oceans. For this purpose, two continuous monitoring water vapour stable isotopes cavity ring-down spectrometers have been installed in July 2015: on-board the Polarstern research vessel and in the Siberian Lena delta Samoylov research station (N 72° 22', E 126° 29'). The Polarstern measurements cover the summer 2015 Arctic campaign from July to mid-October, including six weeks in the Fram Strait region in July- August, followed by a campaign reaching the North Pole and a transect from the Norwegian Sea to the North Sea. These vapour observations are completed by water isotopic measurements in samples from the surface ocean water for Polarstern and from precipitation in Samoylov and Tiksi (120 km south-east of the station). A custom-made designed automatic calibration system has been implemented in a comparable manner for both vapour instruments, based on the injection of different liquid water standards, which are completely vaporised in dry air at high temperature. Subsequent humidity level can be adjusted from 2000 to at least 30000 ppm. For a better resilience, an independent calibration system has been added on the Samoylov instrument, allowing measurements of one standard at humidity levels ranging from 2000 to 15000 ppm: dry air is introduced in a tank containing a large amount of liquid water standard, undergoing evaporation under a controlled environment. The measurement protocol includes an automatic calibration every 25 hours. First instrument characterisation experiments depict a significant isotope-humidity effect at low humidity, dependant on the isotopic composition of the standard. For ambient air, our first isotope

  14. Effects of Reducing the Ambient UV-B Radiation in the High Arctic on Salix arctica and Vaccinium uliginosum

    DEFF Research Database (Denmark)

    Albert, Kristian; Ro-Poulsen, Helge; Mikkelsen, Teis Nørgaard;

    2005-01-01

    Effects of reducing the ambient UV-B radiation on gas exchange and chlorophyll fluores-cence of two dwarf shrub species, Salix arctica and Vaccinium uliginosum, was studied in a high arctic heath in North East Greenland during two growing seasons. Films (Mylar, transmitting ¿ > 320 nm, and Lexan...

  15. Effects of reducing the ambient UV-B radiation in the high Arctic on Salix arctica and Vaccinium uliginosum

    DEFF Research Database (Denmark)

    Albert, K.R.; Ro-Poulsen, H.; Mikkelsen, Teis Nørgaard;

    2005-01-01

    Effects of reducing the ambient UV-B radiation on gas exchange and chlorophyll fluores-cence of two dwarf shrub species, Salix arctica and Vaccinium uliginosum, was studied in a high arctic heath in North East Greenland during two growing seasons. Films (Mylar, transmitting λ > 320 nm, and Lexan,...

  16. Arctic region: new model of geodynamic history

    Science.gov (United States)

    Nikishin, Anatoly; Kazmin, Yuriy; Malyshev, Nikolay; Morozov, Andrey; Petrov, Eugene

    2014-05-01

    Basement of the Arctic shelf areas is characterizes with a complex structure. Age of the defined domains is early Pre-Cambrian, Neoproterozoic to Cambrian (Timanian and Baykalian), early-middle Paleozoic (Caledonian) and late Paleozoic (Uralian, Taimyrian and Ellesmerian). Mesozoic deformations affected Novaya Zemlya, Southern Taimyr and southern parts of the Laptev Sea, the East Siberian Sea, and the Chukchi Sea regions. There are several Paleozoic rift-postrift basins. The North Kara Basin and the Timan-Pechora Basin was formed during the early Ordovician time as subduction-related back-arc rift systems. The East-Barents Basin has the same origin but the age of its formation is late Devonian. Carboniferous rifting took place in the Norwegian part of the Barents Sea, the Chukchi Sea (Hanna Trough Basin) and the Sverdrup Basin. There are also rift-postrift basins of the Mesozoic age. Late Permian to Early Triassic rifting took place in the South Kara Basin; it was connected with both collapse of the Uralian Orogen and activity of the Siberian mantle plume. Aptian to Albian rifting was affected with really big area in the Laptev Sea, the East Siberian Sea and the Chukchi Sea right after the De-Long plume-related magmatic event. Paleogene (mainly Eocene) rifting was also widely spread in these areas. The Arctic Ocean consists of three main domains: the Canada Basin, Alpha-Mendeleev-Podvodnikov-Makarov domain, and the Eurasia Basin. The Canada Basin is a typical oceanic one. There are many uncertainties in the definition of spreading age, but in accordance with the prevalent point of view, it should be early Cretaceous, Neocomian. Alpha-Mendeleev-Podvodnikov-Makarov domain is an enigmatic region. We propose the following scenario for the formation of this domain: Aptian to Cenomanian plume-related large-scale intraplate basalt magmatism was followed by Albian to late Cretaceous rifting. Few axes of rifting were nearly orthogonal to the pre-existing one in the Canada

  17. Vegetation biomass, leaf area index, and NDVI patterns and relationships along two latitudinal transects in arctic tundra

    Science.gov (United States)

    Epstein, H. E.; Walker, D. A.; Raynolds, M. K.; Kelley, A. M.; Jia, G.; Ping, C.; Michaelson, G.; Leibman, M. O.; Kaarlejärvi, E.; Khomutov, A.; Kuss, P.; Moskalenko, N.; Orekhov, P.; Matyshak, G.; Forbes, B. C.; Yu, Q.

    2009-12-01

    Analyses of vegetation properties along climatic gradients provide first order approximations as to how vegetation might respond to a temporally dynamic climate. Until recently, no systematic study of tundra vegetation had been conducted along bioclimatic transects that represent the full latitudinal extent of the arctic tundra biome. Since 1999, we have been collecting data on arctic tundra vegetation and soil properties along two such transects, the North American Arctic Transect (NAAT) and the Yamal Arctic Transect (YAT). The NAAT spans the arctic tundra from the Low Arctic of the North Slope of Alaska to the polar desert of Cape Isachsen on Ellef Ringnes Island in the Canadian Archipelago. The Yamal Arctic Transect located in northwest Siberia, Russia, presently ranges from the forest-tundra transition at Nadym to the High Arctic tundra on Belyy Ostrov off the north coast of the Yamal Peninsula. The summer warmth indices (SWI - sum of mean monthly temperatures greater than 0°C) range from approximately 40 °C months to 3 °C months from south to north. For largely zonal sites along these transects, we systematically collected leaf area index (LAI-2000 Plant Canopy Analyzer), normalized difference vegetation index (NDVI - PSII hand-held spectro-radiometer), and vegetation biomass (clip harvests). Site-averaged LAI ranges from 1.08 to 0 along the transects, yet can be highly variable at the landscape scale. Site-averaged NDVI ranges from 0.67 to 0.26 along the transects, and is less variable than LAI at the landscape scale. Total aboveground live biomass ranges from approximately 700 g m-2 to < 50 g m-2 along the NAAT, and from approximately 1100 g m-2 to < 400 g m-2 along the YAT (not including tree biomass at Nadym). LAI and NDVI are highly correlated logarithmically (r = 0.80) for the entire dataset. LAI is significantly related to total aboveground (live plus dead) vascular plant biomass, although there is some variability in the data (r = 0.63). NDVI is

  18. Chapter 49: A first look at the petroleum geology of the Lomonosov Ridge microcontinent, Arctic Ocean

    Science.gov (United States)

    Moore, T.E.; Grantz, A.; Pitman, J.K.; Brown, P.J.

    2011-01-01

    The Lomonosov microcontinent is an elongated continental fragment that transects the Arctic Ocean between North America and Siberia via the North Pole. Although it lies beneath polar pack ice, the geological framework of the microcontinent is inferred from sparse seismic reflection data, a few cores, potential field data and the geology of its conjugate margin in the Barents-Kara Shelf. Petroleum systems inferred to be potentially active are comparable to those sourced by condensed Triassic and Jurassic marine shale of the Barents Platform and by condensed Jurassic and (or) Cretaceous shale probably present in the adjacent Amerasia Basin. Cenozoic deposits are known to contain rich petroleum source rocks but are too thermally immature to have generated petroleum. For the 2008 USGS Circum Arctic Resource Appraisal (CARA), the microcontinent was divided into shelf and slope assessment units (AUs) at the tectonic hinge line along the Amerasia Basin margin. A low to moderate probability of accumulation in the slope AU yielded fully risked mean estimates of 123 MMBO oil and 740 BCF gas. For the shelf AU, no quantitative assessment was made because the probability of petroleum accumulations of the 50 MMBOE minimum size was estimated to be less than 10% owing to rift-related uplift, erosion and faulting. ?? 2011 The Geological Society of London.

  19. Potential change in forest types and stand heights in central Siberia in a warming climate

    International Nuclear Information System (INIS)

    Previous regional studies in Siberia have demonstrated climate warming and associated changes in distribution of vegetation and forest types, starting at the end of the 20th century. In this study we used two regional bioclimatic envelope models to simulate potential changes in forest types distribution and developed new regression models to simulate changes in stand height in tablelands and southern mountains of central Siberia under warming 21st century climate. Stand height models were based on forest inventory data (2850 plots). The forest type and stand height maps were superimposed to identify how heights would change in different forest types in future climates. Climate projections from the general circulation model Hadley HadCM3 for emission scenarios B1 and A2 for 2080s were paired with the regional bioclimatic models. Under the harsh A2 scenario, simulated changes included: a 80%–90% decrease in forest-tundra and tundra, a 30% decrease in forest area, a ∼400% increase in forest-steppe, and a 2200% increase in steppe, forest-steppe and steppe would cover 55% of central Siberia. Under sufficiently moist conditions, the southern and middle taiga were simulated to benefit from 21st century climate warming. Habitats suitable for highly-productive forests (≥30–40 m stand height) were simulated to increase at the expense of less productive forests (10–20 m). In response to the more extreme A2 climate the area of these highly-productive forests would increase 10%–25%. Stand height increases of 10 m were simulated over 35%–50% of the current forest area in central Siberia. In the extremely warm A2 climate scenario, the tall trees (25–30 m) would occur over 8%–12% of area in all forest types except forest-tundra by the end of the century. In forest-steppe, trees of 30–40 m may cover some 15% of the area under sufficient moisture. (letter)

  20. Using MODIS NDVI products for vegetation state monitoring on the oil production territory in Western Siberia

    OpenAIRE

    Kovalev Anton; Tokareva Olga

    2016-01-01

    Article describes the results of using remote sensing data for vegetation state monitoring on the oil field territories in Western Siberia. We used MODIS data product providing the normalized difference vegetation index (NDVI) values. Average NDVI values of each studied area were calculated for the period from 2010 to 2015 with one year interval for June, July and August. Analysis was carried out via an open tool of geographic information system QGIS used for spatial analysis and calculation ...

  1. Simulation of atmospheric CO2 over Europe and western Siberia using the regional scale model REMO

    OpenAIRE

    Chevillard, Anne; Karstens, Ute; Ciais, Philippe; Lafont, Sébastien; Heimann, Martin

    2002-01-01

    The spatial distribution and the temporal variability of atmospheric CO2 over Europe and western Siberia are investigated using the regional atmospheric model, REMO. The model, of typical horizontal resolution 50 km, is part of a nested modelling framework that has been established as a concerted action during the EUROSIBERIAN CARBONFLUX project. In REMO, the transport of CO2 is simulated together with climate variables, which offers the possibility of calculating at each time step the land a...

  2. Potential change in forest types and stand heights in central Siberia in a warming climate

    Science.gov (United States)

    Tchebakova, N. M.; Parfenova, E. I.; Korets, M. A.; Conard, S. G.

    2016-03-01

    Previous regional studies in Siberia have demonstrated climate warming and associated changes in distribution of vegetation and forest types, starting at the end of the 20th century. In this study we used two regional bioclimatic envelope models to simulate potential changes in forest types distribution and developed new regression models to simulate changes in stand height in tablelands and southern mountains of central Siberia under warming 21st century climate. Stand height models were based on forest inventory data (2850 plots). The forest type and stand height maps were superimposed to identify how heights would change in different forest types in future climates. Climate projections from the general circulation model Hadley HadCM3 for emission scenarios B1 and A2 for 2080s were paired with the regional bioclimatic models. Under the harsh A2 scenario, simulated changes included: a 80%-90% decrease in forest-tundra and tundra, a 30% decrease in forest area, a ˜400% increase in forest-steppe, and a 2200% increase in steppe, forest-steppe and steppe would cover 55% of central Siberia. Under sufficiently moist conditions, the southern and middle taiga were simulated to benefit from 21st century climate warming. Habitats suitable for highly-productive forests (≥30-40 m stand height) were simulated to increase at the expense of less productive forests (10-20 m). In response to the more extreme A2 climate the area of these highly-productive forests would increase 10%-25%. Stand height increases of 10 m were simulated over 35%-50% of the current forest area in central Siberia. In the extremely warm A2 climate scenario, the tall trees (25-30 m) would occur over 8%-12% of area in all forest types except forest-tundra by the end of the century. In forest-steppe, trees of 30-40 m may cover some 15% of the area under sufficient moisture.

  3. Oil and Water Don't Mix: Risk on Tap in Western Siberia

    OpenAIRE

    Wernstedt, Kris

    1996-01-01

    In common with other areas throughout the Russian Federation, western Siberia faces formidable environmental pollution, a problem that in part is the legacy of the highly centralized Soviet era when meeting production quotas was the raison d'être for many managers of economic enterprises. In this region, over the last thirty years the near singular focus on short term oil production has led to severe contamination of the area's surface and groundwater supplies, threatening both human and ecol...

  4. Estimation of the prevalence and causes of infertility in western Siberia.

    OpenAIRE

    Philippov, O. S.; Radionchenko, A. A.; Bolotova, V. P.; Voronovskaya, N. I.; Potemkina, T. V.

    1998-01-01

    The study examined the epidemiology and causes of infertility in Tomsk, Western Siberia, using methodological approaches recommended by WHO and was based on the findings for a randomly selected sample of 2000 married women aged 18-45 years. Among the respondents, 333 couples were considered infertile since they had not conceived after 12 months or more of unprotected intercourse. This group of infertile couples was offered comprehensive clinical investigations but only 186 couples completed t...

  5. Air Pollution in Siberia. A Volume and Risk-Weighted Analysis of a Siberian Pollution Database

    OpenAIRE

    Warner-Merl, N.K.

    1998-01-01

    Air pollution from industrial centers in Siberia pose observable environmental threats. Siberian ecosystems have begun to show stress from the accumulation of pollution depositions that come from cities and industrial plants. While some uncertainty exists as to the long-term effects of air pollution upon forests, in measurable terms such as human mortality and incidence of disease, forest species decline or forest dieback, observable impacts indicate that there is a cause for concern. Industr...

  6. Seismic Investigation of El'gygytgyn Lake, Chukotka (NE Siberia)

    Science.gov (United States)

    Gebhardt, C.; Niessen, F.; Kopsch, C.; Wagner, B.

    2004-12-01

    Lake El'gygytgyn is a 3.6 Mio years old crater lake located in Central Chukotka, NE Russia, with a water depth of 170 m and a diameter of 12 km. Not having been glaciated ever since, it would reveal a paleoclimatic record unique in the Arctic realm. During the last years it has become a major focus of multi-disciplinary international research as a target for deep drilling in the near future. During expeditions in 2000 and 2003, reflection and refraction seismic combined with high resolution 3.5 kHz echosound profiling was carried out. Raytracing of the sonobuoy refraction data reveals a four-layer model of the lake that is interpreted as follows: (a) upper sedimentary unit, consisting of lacustrine muds with velocities of around 1500 m/s and a thickness of about 170 m, (b) lower sedimentary unit, consisting of lacustrine muds with velocities of around 1650 m/s and a thickness between 80 and 200 m, (c) fallback breccia with velocities of about 3000 m/s and a thickness between 50 and 300 m and (d) brecciated bedrock with velocities of > 3600 m/s. The brecciated bedrock forms a central uplift structure which is almost levelled by the overlying fallback breccia. The lower sedimentary unit drapes the smooth topography of the fallback breccia, whereas the upper sedimentary unit is almost flat. Small faults are associated with the central uplift structure and have been active until recently. Reflection seismic data indicate that the upper sedimentary unit is characterized by well stratified sediments, whereas the lower sedimentary unit is more massive. The upper sedimentary unit is locally intercalated with debris flows to a depth of at least 160 m subbottom. Debris flows are more common in the western part of the lake and along the slopes. The 3.5 kHz profiling allows a detailed mapping of the debris flow distribution. At the proposed drillsite near the centre of the lake, the sediments appear to be well stratified and largely unaffected by debris flows and promises a

  7. Time varying arctic climate change amplification

    Energy Technology Data Exchange (ETDEWEB)

    Chylek, Petr [Los Alamos National Laboratory; Dubey, Manvendra K [Los Alamos National Laboratory; Lesins, Glen [DALLHOUSIE U; Wang, Muyin [NOAA/JISAO

    2009-01-01

    During the past 130 years the global mean surface air temperature has risen by about 0.75 K. Due to feedbacks -- including the snow/ice albedo feedback -- the warming in the Arctic is expected to proceed at a faster rate than the global average. Climate model simulations suggest that this Arctic amplification produces warming that is two to three times larger than the global mean. Understanding the Arctic amplification is essential for projections of future Arctic climate including sea ice extent and melting of the Greenland ice sheet. We use the temperature records from the Arctic stations to show that (a) the Arctic amplification is larger at latitudes above 700 N compared to those within 64-70oN belt, and that, surprisingly; (b) the ratio of the Arctic to global rate of temperature change is not constant but varies on the decadal timescale. This time dependence will affect future projections of climate changes in the Arctic.

  8. History of sea ice in the Arctic

    DEFF Research Database (Denmark)

    Polyak, Leonid; Alley, Richard B.; Andrews, John T.;

    2010-01-01

    Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past. This inf......Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past....... This information can be provided by proxy records fromthe Arctic Ocean floor and from the surrounding coasts. Although existing records are far from complete, they indicate that sea ice became a feature of the Arctic by 47 Ma, following a pronounced decline in atmospheric pCO2 after the Paleocene–Eocene Thermal...

  9. The Arctic policy of China and Japan

    DEFF Research Database (Denmark)

    Tonami, Aki

    2014-01-01

    At the May 2013 Arctic Council Ministerial Meeting, five Asian states, namely China, Japan, India, Singapore and South Korea, were accepted to become new Permanent Observers at the Arctic Council. Nonetheless, little attention has been paid to the Asian states and their interest in the Arctic. Most...... discussions have focused on China and the assessment of China’s interest in the Arctic is divided. This paper attempts to fill this gap by presenting and comparing the various components of the Arctic policies of China and Japan. Referring to Putnam’s model of the “two-level game” and Young’s categorization...... of Arctic stakeholders’ interests, data from policy documents and interviews with relevant stakeholders were analysed. This analysis shows the Chinese and Japanese governments are in the gradual process of consolidating their Arctic policies, but both China and Japan see the Arctic less as a strategically...

  10. Sea Ice, Hydrocarbon Extraction, Rain-on-Snow and Tundra Reindeer Nomadism in Arctic Russia

    Science.gov (United States)

    Forbes, B. C.; Kumpula, T.; Meschtyb, N.; Laptander, R.; Macias-Fauria, M.; Zetterberg, P.; Verdonen, M.

    2015-12-01

    It is assumed that retreating sea ice in the Eurasian Arctic will accelerate hydrocarbon development and associated tanker traffic along Russia's Northern Sea Route. However, oil and gas extraction along the Kara and Barents Sea coasts will likely keep developing rapidly regardless of whether the Northwest Eurasian climate continues to warm. Less certain are the real and potential linkages to regional biota and social-ecological systems. Reindeer nomadism continues to be a vitally important livelihood for indigenous tundra Nenets and their large herds of semi-domestic reindeer. Warming summer air temperatures over the NW Russian Arctic have been linked to increases in tundra productivity, longer growing seasons, and accelerated growth of tall deciduous shrubs. These temperature increases have, in turn, been linked to more frequent and sustained summer high-pressure systems over West Siberia, but not to sea ice retreat. At the same time, winters have been warming and rain-on-snow (ROS) events have become more frequent and intense, leading to record-breaking winter and spring mortality of reindeer. What is driving this increase in ROS frequency and intensity is not clear. Recent modelling and simulation have found statistically significant near-surface atmospheric warming and precipitation increases during autumn and winter over Arctic coastal lands in proximity to regions of sea-ice loss. During the winter of 2013-14 an extensive and lasting ROS event led to the starvation of 61,000 reindeer out of a population of ca. 300,000 animals on Yamal Peninsula, West Siberia. Historically, this is the region's largest recorded mortality episode. More than a year later, participatory fieldwork with nomadic herders during spring-summer 2015 revealed that the ecological and socio-economic impacts from this extreme event will unfold for years to come. There is an urgent need to understand whether and how ongoing Barents and Kara Sea ice retreat may affect the region's ancient

  11. Electronic atlas of the Russian Arctic coastal zone: natural conditions and technogenic risk

    Science.gov (United States)

    Drozdov, D. S.; Rivkin, F. M.; Rachold, V.

    2004-12-01

    The Arctic coast is characterized by a diversity of geological-geomorphological structures and geocryological conditions, which are expected to respond differently to changes in the natural environment and in anthropogenic impacts. At present, oil fields are prospected and developed and permanent and temporary ports are constructed in the Arctic regions of Russia. Thus, profound understanding of the processes involved and measures of nature conservation for the coastal zone of the Arctic Seas are required. One of the main field of Arctic coastal investigations and database formation of coastal conditions is the mapping of the coasts. This poster presents a set of digital maps including geology, quaternary sediments, landscapes, engineering-geology, vegetation, geocryology and a series of regional sources, which have been selected to characterize the Russian Arctic coast. The area covered in this work includes the 200-km-wide band along the entire Russian Arctic coast from the Norwegian boundary in the west to the Bering Strait in the east. Methods included the collection of the majority of available hard copies of cartographic material and their digital formats and the transformation of these sources into a uniform digital graphic format. The atlas consists of environmental maps and maps of engineering-geological zoning. The set of environmental maps includes geology, quaternary sediments, landscapes and vegetation of the Russian Arctic coast at a scale of 1:4000000. The set of engineering-geocryological maps includes a map of engineering-geocryological zoning of the Russian Arctic coast, a map of the intensity of destructive coastal process and a map of industrial impact risk assessment ( 1:8000000 scale). Detailed mapping has been performed for key sites (at a scale of 1:100000) in order to enable more precise estimates of the intensity of destructive coastal process and industrial impact. The engineering-geocryological map of the Russian Arctic coast was

  12. Source apportionment of particles at Station Nord, North East Greenland during 2008–2010 using COPREM and PMF analysis

    DEFF Research Database (Denmark)

    Nguyen, Quynh; Skov, Henrik; Sørensen, Lise Lotte;

    2013-01-01

    , which were all influenced by metal industries. One anthropogenic source was dominated by Zn of which air mass back trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model suggested a Canadian Arctic origin, despite certain influences from Southern and Eastern......In order to develop strategies for controlling and reducing Arctic air pollution, there is a need to understand the basic mechanisms for determining the fate of air pollution in the Arctic. Sources of atmospheric particles at Station Nord (81° 36' N, 16° 40' W) in North East Greenland were...

  13. In Brief: Arctic Report Card

    Science.gov (United States)

    Showstack, Randy

    2009-11-01

    The 2009 annual update of the Arctic Report Card, issued on 22 October, indicates that “warming of the Arctic continues to be widespread, and in some cases dramatic. Linkages between air, land, sea, and biology are evident.” The report, a collaborative effort of 71 national and international scientists initiated in 2006 by the Climate Program Office of the U.S. National Oceanic and Atmospheric Administration (NOAA), highlights several concerns, including a change in large-scale wind patterns affected by the loss of summer sea ice; the replacement of multiyear sea ice by first-year sea ice; warmer and fresher water in the upper ocean linked to new ice-free areas; and the effects of the loss of sea ice on Arctic plant, animal, and fish species. “Climate change is happening faster in the Arctic than any other place on Earth-and with wide-ranging consequences,” said NOAA administrator Jane Lubchenco. “This year“s Arctic Report Card underscores the urgency of reducing greenhouse gas pollution and adapting to climate changes already under way.”

  14. NOAA Atmospheric Baseline Observatories in the Arctic: Alaska & Greenland

    Science.gov (United States)

    Vasel, B. A.; Butler, J. H.; Schnell, R. C.; Crain, R.; Haggerty, P.; Greenland, S.

    2013-12-01

    The National Oceanic and Atmospheric Administration (NOAA) operates two year-round, long-term climate research facilities, known as Atmospheric Baseline Observatories (ABOs), in the Arctic Region. The Arctic ABOs are part of a core network to support the NOAA Global Monitoring Division's mission to acquire, evaluate, and make available accurate, long-term records of atmospheric gases, aerosol particles, and solar radiation in a manner that allows the causes of change to be understood. The observatory at Barrow, Alaska (BRW) was established in 1973 and is now host to over 200 daily measurements. Located a few kilometers to the east of the village of Barrow at 71.3° N it is also the northernmost point in the United States. Measurement records from Barrow are critical to our understanding of the Polar Regions including exchange among tundra, atmosphere, and ocean. Multiple data sets are available for carbon cycle gases, halogenated gases, solar radiation, aerosol properties, ozone, meteorology, and numerous others. The surface, in situ carbon dioxide record alone consists of over 339,000 measurements since the system was installed in July 1973. The observatory at Summit, Greenland (SUM) has been a partnership with the National Science Foundation (NSF) Division of Polar Programs since 2004, similar to that for South Pole. Observatory data records began in 1997 from this facility located at the top of the Greenland ice sheet at 72.58° N. Summit is unique as the only high-altitude (3200m), mid-troposphere, inland, Arctic observatory, largely free from outside local influences such as thawing tundra or warming surface waters. The measurement records from Summit help us understand long-range transport across the Arctic region, as well as interactions between air and snow. Near-real-time data are available for carbon cycle gases, halogenated gases, solar radiation, aerosol properties, meteorology, ozone, and numerous others. This poster will highlight the two facilities

  15. Fate of terrestrial colored dissolved organic matter (CDOM) in the Arctic Ocean: exported or removed?

    Science.gov (United States)

    Granskog, M. A.; Stedmon, C. A.; Dodd, P. A.; Amon, R. M. W.; Pavlov, A. K.; de Steur, L.; Hansen, E.

    2012-04-01

    Colored dissolved organic matter (CDOM) was measured with hydrographic parameters (salinity, d18O and inorganic nutrients) across Fram Strait. East Greenland Current (EGC) surface waters showed a pronounced CDOM absorption maximum between 30 and 120 m depth associated with both river and sea ice brine-enriched water, characteristic of polar mixed layer water and upper halocline water. Lowest CDOM was found in the Atlantic inflow within the West Spitsbergen Current (WSC). Although applied elsewhere in the Arctic, we show that the salinity-CDOM relationship not suitable for evaluating the mixing behavior of CDOM (conservative vs. non-conservative) in Fram Strait. The strong correlation between meteoric water and optical properties of CDOM are indicative of the terrigenous origin of CDOM in the EGC and marine origin in WSC. Based on CDOM absorption in Polar Water and comparison with an Arctic river discharge weighted mean, we estimate that a 68% integrated loss of CDOM absorption across 250-600 nm has occurred, with a preferential removal of absorption at longer wavelengths reflecting the loss of high molecular weight material. Budget calculations of CDOM exports through Fram Strait using modeled volume transports indicate that the net southward export of CDOM in Fram Strait equals to 8 to 14% of the total riverine CDOM inputs to the Arctic Ocean, thus physical export is not a major sink of CDOM. We propose that CDOM can aid in discriminating glacial melt waters from Arctic riverine freshwater on the east Greenland shelf.

  16. Bottom Sediment Granulometric Data for the Continental Margins of the Bering, Chukchi, East Siberia, Laptev, and Beaufort Seas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are part of Roberts, Richard W., University of Washington, Department of Oceanography Special Report No. 70, Bottom Sediment Granulometric Data for the...

  17. Environmental radioactivity in the Arctic

    International Nuclear Information System (INIS)

    The conference considered several broad themes: (1) assessment of releases from landbased sources and river transport, (2) assessment of dumping of nuclear waste, (3) arctic radioecology, (4) assessment of impacts of nuclear explosions and accidents, (5) nuclear safety and consequences of nuclear accidents in the arctic, and (6) waste management. The presentations demonstrated that current levels of radioactivity in the Arctic are generally low. The two most important sources are global fallout from the nuclear weapons tests of the 1950's and 1960's, and discharges to the sea from reprocessing plants in Western Europe which are transported northward by prevailing currents. The conference was attended by scientists from 17 countries and served as a forum for collection and dissemination of information on the range of themes and described above. It is hoped that this will serve to increase awareness of areas of uncertainty and act as a stimulus to further research

  18. Decadal dynamics of Arctic continental water cycle in the framework of MONARCH-A .

    Science.gov (United States)

    Dhomps, A.-L.; Zakharova, E. A.; Kouraev, A. V.; Biancamaria, S.; Mognard, N. M.

    2012-04-01

    The main objective of MONARCH-A FP7 European program is to generate a dedicated information package tailored to a subset of multidisciplinary essential climate variables and their mutual forcing and feedback mechanisms associated with changes in terrestrial carbon and water fluxes, sea level and ocean circulation and the marine carbon cycle in the high latitude and Arctic regions. High latitude regions are predicted to suffer much greater warming than lower latitudes as a result of climate change. This will cause drastic changes in the carbon and water balance of the region, with associated large effects on snow cover, soil freeze-thaw periods, soil moisture, permafrost, growing season, land cover, greenhouse gas fluxes and albedo. Of crucial concern are the feedbacks between these land surface processes and climate warming; this is recognized as one of the greatest sources of uncertainty in climate prediction (IPCC 2007). Decadal change in snow properties and dynamics of high latitude water bodies are analyzed over the last 20 years. Snow cover, depth and duration are good indicators of climate change and have strong effects on fresh water discharge into the Arctic Ocean, albedo, plant growth and vegetation growing periods. While the large numbers of lakes at high latitudes are important for evapo-transpiration, runoff, groundwater and methane emissions. We analyze various satellite-derived (SSM/I and radar altimeters) environmental parameters (snow extent, depth and duration, fraction of water surface and wet zones extent) in the context of climatic changes (from reanalysis and in situ data) and their role in the Arctic water cycle with specific attention to Western Siberia. We gratefully acknowledge the ESA DUE Permafrost for the data used for the inter-comparison. This research has been done in the framework of the FP7 MONARCH-A project, Russian-French cooperation GDRI "CAR-WET-SIB", French ANR "CLASSIQUE" project.

  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. Oxygen and carbon isotope composition of Quaternary bivalve shells as a water mass indicator: Last interglacial and Holocene, East Greenland

    DEFF Research Database (Denmark)

    Israelson, C.; Buchardt, Bjørn; Funder, S.V.;

    1994-01-01

    Oxygen and carhon isotope composition of arctic bivahe shells are used in an attempt to reCO'1struct -.urface water temperature and salinities in Scoresby Sund. East Greenland. The oxygen i:;otope compositions or .1,tw mllicuf£!. Hialclla arctica and Tridmlla hOl'm!is han~ been compared with pres......Oxygen and carhon isotope composition of arctic bivahe shells are used in an attempt to reCO'1struct -.urface water temperature and salinities in Scoresby Sund. East Greenland. The oxygen i:;otope compositions or .1,tw mllicuf£!. Hialclla arctica and Tridmlla hOl'm!is han~ been compared...

  1. Arctic sea ice melt onset from passive microwave satellite data: 1979–2012

    Directory of Open Access Journals (Sweden)

    A. C. Bliss

    2014-06-01

    Full Text Available An updated version of the Snow Melt Onset Over Arctic Sea Ice from SMMR and SSM/I-SSMIS Brightness Temperatures is now available. The data record has been re-processed and extended to cover the years 1979–2012. From this data set, a statistical summary of melt onset (MO dates on Arctic sea ice is presented. The mean MO date for the Arctic Region is 13 May (132.5 DOY with a standard deviation of ±7.3 days. Regionally, mean MO dates vary from 15 March (73.2 DOY in the St. Lawrence Gulf to 10 June (160.9 DOY in the Central Arctic. Statistically significant decadal trends indicate that MO is occurring 6.6 days decade−1 earlier in the year for the Arctic Region. Regionally, MO trends are as great as −11.8 days decade−1 in the East Siberian Sea. The Bering Sea is an outlier and MO is occurring 3.1 days decade−1 later in the year.

  2. Arctic sea ice melt, the Polar vortex, and mid-latitude weather: Are they connected?

    Science.gov (United States)

    Vihma, Timo; Overland, James; Francis, Jennifer; Hall, Richard; Hanna, Edward; Kim, Seong-Joong

    2015-04-01

    The potential of recent Arctic changes to influence broader hemispheric weather is a difficult and controversial topic with considerable skepticism, as time series of potential linkages are short (relative to chaotic weather events is small. A way forward is through further understanding of potential atmospheric dynamic mechanisms. Although not definitive of change in a statistical or in a causality sense, the exceptionally warm Arctic winters since 2007 do contain increased variability according to some climate indices, with six negative (and two positive) Arctic Oscillation atmospheric circulation index events that created meridional flow reaching unusually far north and south. High pressure anomalies developed east of the Ural Mountains in Russia in response to sea-ice loss in the Barents/Kara Seas, which initiated eastward-propagating wave trains of high and low pressure that advected cold air over central and eastern Asia. Increased Greenland blocking and greater geopotential thickness related to low-level temperatures increases led to northerly meridional flow into eastern North America, inducing persistent cold periods. Arctic connections in Europe and western North America are less clear. The quantitative impact of potential Arctic change on mid-latitude weather will not be resolved within the foreseeable future, yet new approaches to high-latitude atmospheric dynamics can contribute to improved extended range forecasts as outlined by the WMO/Polar Prediction Program and other international activities.

  3. «We Felt the Bitter Satisfaction of Our Shared Victory”: the Theme and Images of the ‘Great War’ in the Official and Pro-government Periodical Press of the White Siberia (June 1918 – December 1919

    Directory of Open Access Journals (Sweden)

    Dmitry N. Shevelev

    2014-09-01

    Full Text Available The article, using the data of official and pro-government periodical press, issued in the east of Russia since summer of 1918 to 1919, considers the propaganda, made by the Omsk government out of the recollections of the First World War. The author came to the conclusion that the whole set of propaganda texts, presented in numerous declarations, booklets, newspaper articles, interviews, reviews, notes and feuilletons should be considered as a specific narrative with own actualization contexts, representation composition and scenario. The political discourse of the White Siberia presented the First World War as a specific starting point, backbone, structuring the political space. Besides, the ‘Great War’ played the significant role in the construction of the new political identity, based on the national, sovereign and patriotic values and the memory of the former glories of Russia.

  4. Response of Arctic Temperature to Changes in Emissions of Short-Lived Climate Forcers

    Science.gov (United States)

    Sand, M.; Berntsen, T.; von Salzen, K.; Flanner, M.; Langner, J.; Victor, D. G.

    2015-12-01

    There is growing scientific and political interest in the impacts of climate change and anthropogenic emissions on the Arctic. Over recent decades temperatures in the Arctic have increased twice the global rate, largely due to ice albedo and temperature feedbacks. While deep cuts in global CO2 emissions are required to slow this warming, there is also growing interest in the potential for reducing short lived climate forcers (SLCFs). Politically, action on SLCFs may be particularly promising because the benefits of mitigation appear promptly and there are large co-benefits in terms of improved air quality. This study is the first to systematically quantify the Arctic climate impact of regional SLCF emissions, taking into account BC, sulphur dioxide (SO2), nitrogen oxides (NOx), volatile hydrocarbons (VOC), organic carbon (OC) and tropospheric ozone, their transport processes and transformations in the atmosphere. Using several chemical transport models we perform detailed radiative forcing calculations from emissions of these species. Geographically we separate emissions into seven source regions that correspond with the national groupings of the Arctic Council, the leading body organizing international policy in the region (the United States, Canada, the Nordic countries, the rest of Europe, Russia, East and South Asia, and the rest of the world). We look at six main sectors known to account for [nearly all] of these emissions: households (domestic), energy/industry/waste, transport, agricultural fires, grass/forest fires, and gas flaring. We find that the largest Arctic warming source is from emissions within the Asian nations. However, the Arctic is most sensitive, per unit mass emitted, to SLCFs emissions from a small number of activities within the Arctic nations themselves. A stringent, but technically feasible SLCFs mitigation scenario, phased in from 2015 through 2030, can cut warming by 0.2 K in 2050.

  5. Circum-Arctic Map Compilation

    Science.gov (United States)

    Saltus, Richard W.; Gaina, Carmen

    2007-05-01

    Second Workshop of the Circum-Arctic Geophysical Maps Project, Trondheim, Norway, 12-13 February 2007 The eyes of the world are increasingly focused on the polar regions. Exploration and assessment of energy and mineral resources for the growing world economy are moving to high-latitude frontier areas. The effects of climatic changes are particularly pronounced at these ends of the Earth and have already attracted worldwide attention and concern. Many recent articles related to the International Polar Year underscore the importance of even basic mapping of the Arctic and Antarctic.

  6. Characteristics of water-vapour inversions observed over the Arctic by Atmospheric Infrared Sounder (AIRS and radiosondes

    Directory of Open Access Journals (Sweden)

    A. Devasthale

    2011-05-01

    Full Text Available An accurate characterization of the vertical structure of the Arctic atmosphere is useful in climate change and attribution studies as well as for the climate modelling community to improve projections of future climate over this highly sensitive region. Here, we investigate one of the dominant features of the vertical structure of the Arctic atmosphere, i.e. water-vapour inversions, using eight years of Atmospheric Infrared Sounder data (2002–2010 and radiosounding profiles released from the two Arctic locations (North Slope of Alaska at Barrow and during SHEBA. We quantify the characteristics of clear-sky water vapour inversions in terms of their frequency of occurrence, strength and height covering the entire Arctic for the first time.

    We found that the frequency of occurrence of water-vapour inversions is highest during winter and lowest during summer. The inversion strength is, however, higher during summer. The observed peaks in the median inversion-layer heights are higher during the winter half of the year, at around 850 hPa over most of the Arctic Ocean, Siberia and the Canadian Archipelago, while being around 925 hPa during most of the summer half of the year over the Arctic Ocean. The radiosounding profiles agree with the frequency, location and strength of water-vapour inversions in the Pacific sector of the Arctic. In addition, the radiosoundings indicate that multiple inversions are the norm with relatively few cases without inversions. The amount of precipitable water within the water-vapour inversion structures is estimated and we find a distinct, two-mode contribution to the total column precipitable water. These results suggest that water-vapour inversions are a significant source to the column thermodynamics, especially during the colder winter and spring seasons. We argue that these inversions are a robust metric to test the reproducibility of thermodynamics within climate models. An accurate statistical

  7. Changes in Arctic warm and cold spell occurrence during winter and summer

    Science.gov (United States)

    Matthes, Heidrun; Rinke, Annette; Dethloff, Klaus

    2016-04-01

    In the Arctic, climate change manifests with the strongest warming trends on the globe, especially in the cold season, associated with Arctic Amplification. However, climate change is not restricted to mean temperature but also expresses itself in changes of temperature extremes. It is under debate if climate extremes change similarly strong, and what mechanisms apply. Our study provides detailed regional information about two selected temperature extreme indices in the Arctic, namely warm and cold spells in winter and summer. Both indices detect lasting cold respectively warm periods that are based on extreme temperatures: cold nights as days where the daily minimum temperature is below the 10th percentile of minimum temperatures and warm day times where the daily maximum temperature is above the 90th percentile of maximum temperatures. We analyze the temporal evolution and variability of warm and cold spells from 1979-2013, based on daily station data and the ERA-Interim reanalysis. Calculated trends from both datasets suggest a widespread decrease of cold spells in winter and summer of up to -4 days/decade, with regional patches where trends are statistically significant throughout the Arctic. Winter trends are spatially heterogeneous, the reanalysis also shows small areas with statistically significant increases of cold spells throughout Siberia. Calculated changes in warm spells from both datasets are mostly small throughout the Arctic (below ± 1 day/decade) and statistically not significant. Remarkable exceptions are the Lena river basin in winter with a statistically significant decrease of up to 1.5 days/decade and areas in Scandinavia with statistically significant increases of up to 2.5 days/decade in winter and summer (again from both datasets). Changes in both warm and cold spells may be caused by two separate mechanisms: changes in occurrence of the underlying extremes (changes in the number of cold nights and warm daytimes) or changes in the temporal

  8. Effects of Conversion from Boreal Forest to Arctic Steppe on Soil Communities and Ecosystem Carbon Pools

    Science.gov (United States)

    Han, P. D.; Natali, S.; Schade, J. D.; Zimov, N.; Zimov, S. A.

    2014-12-01

    The end of the Pleistocene marked the extinction of a great variety of arctic megafauna, which, in part, led to the conversion of arctic grasslands to modern Siberian larch forest. This shift may have increased the vulnerability of permafrost to thawing because of changes driven by the vegetation shift; the higher albedo of grassland and low insulation of snow trampled by animals may have decreased soil temperatures and reduced ground thaw in the grassland ecosystem, resulting in protection of organic carbon in thawed soil and permafrost. To test these hypothesized impacts of arctic megafauna, we examined an experimental reintroduction of large mammals in northeast Siberia, initiated in 1988. Pleistocene Park now contains 23 horses, three musk ox, one bison, and several moose in addition to the native fauna. The park is 16 square km with a smaller enclosure (animals spend most of their time and our study was focused. We measured carbon-pools in forested sites (where scat surveys showed low animal use), and grassy sites (which showed higher use), within the park boundaries. We also measured thaw depth and documented the soil invertebrate communities in each ecosystem. There was a substantial difference in number of invertebrates per kg of organic soil between the forest (600 ± 250) and grassland (300 ± 250), though these differences were not statistically significant they suggest faster nutrient turnover in the forest or a greater proportion of decomposition by invertebrates than other decomposers. While thaw depth was deeper in the grassland (60 ± 4 cm) than in the forest (40 ± 6 cm), we did not detect differences in organic layer depth or percent organic matter between grassland and forest. However, soil in the grassland had higher bulk density, and higher carbon stocks in the organic and mineral soil layers. Although deeper thaw depth in the grassland suggests that more carbon is available to microbial decomposers, ongoing temperature monitoring will help

  9. Arctic Glass: Innovative Consumer Technology in Support of Arctic Research

    Science.gov (United States)

    Ruthkoski, T.

    2015-12-01

    The advancement of cyberinfrastructure on the North Slope of Alaska is drastically limited by location-specific conditions, including: unique geophysical features, remoteness of location, and harsh climate. The associated cost of maintaining this unique cyberinfrastructure also becomes a limiting factor. As a result, field experiments conducted in this region have historically been at a technological disadvantage. The Arctic Glass project explored a variety of scenarios where innovative consumer-grade technology was leveraged as a lightweight, rapidly deployable, sustainable, alternatives to traditional large-scale Arctic cyberinfrastructure installations. Google Glass, cloud computing services, Internet of Things (IoT) microcontrollers, miniature LIDAR, co2 sensors designed for HVAC systems, and portable network kits are several of the components field-tested at the Toolik Field Station as part of this project. Region-specific software was also developed, including a multi featured, voice controlled Google Glass application named "Arctic Glass". Additionally, real-time sensor monitoring and remote control capability was evaluated through the deployment of a small cluster of microcontroller devices. Network robustness was analyzed as the devices delivered streams of abiotic data to a web-based dashboard monitoring service in near real time. The same data was also uploaded synchronously by the devices to Amazon Web Services. A detailed overview of solutions deployed during the 2015 field season, results from experiments utilizing consumer sensors, and potential roles consumer technology could play in support of Arctic science will be discussed.

  10. Upper Arctic Ocean velocity structure from in-situ observations

    Science.gov (United States)

    Recinos, Beatriz; Rabe, Benjamin; Schauer, Ursula

    2016-04-01

    The gross circulation of the upper and intermediate layers of the Arctic Ocean has been inferred from water mass properties: the mixed layer, containing fresh water from the shelf seas, travels from Siberia towards the Atlantic sector, and the saline and warm layer of Atlantic origin below, follows cyclonic pathways along topographic features. Direct observations of the flow below the sea ice are, however, sparse and difficult to obtain. This research presents the analysis of a unique time series/section of in situ velocity measurements obtained by a drifting ice-tethered platform in the Transpolar Drift near the North Pole. Two instruments were used to obtain in situ measurements of velocity, temperature, salinity and pressure: an Ice-tethered Acoustic Current profiler (ITAC) and an Ice-tethered Profiler (ITP). Both systems were deployed in the Amundsen basin, during the Arctic Ocean expedition ARK XXII/2 of the German Research Vessel Polarstern in September 2007. The systems transmitted profile data from the 14th of September to the 29th of November 2007 and covered a maximum depth range of 23 to 400 m. The results are compared to observations by a shipboard Acoustic Doppler Current Profiler (ADCP) from the 2011 Polarstern expedition ARK-XXVI/3, and wind and ice concentration from satellite reanalysis products. The data set allows an overview of the upper and intermediate circulation along the Lomonosov Ridge. Near-surface velocity and ice drift obtained by the ITAC unit are consistent with the Transpolar Drift Current. Ekman transports calculated from the observed ice drift and assumed ice-ocean drag behaviour suggest that Ekman dynamics influenced velocities at depths greater than the Ekman layer. Direct velocity observations in combination with water mass analyses from the temperature and salinity data, suggest the existence of a current along the Eurasian side of the Lomonosov Ridge within the warm Atlantic layer below the cold halocline. At those depths

  11. East Asia Rolls On

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The economic recovery in East Asia remains unchanged on its upward trajectory despite the earthquake and devastating tsunami in Japan on March 11.Growth in East Asia slowed after a sharp rebound from the global financial crisis but is improving nonetheless.The World Bank’s East Asia and Pacific Economic Update issued on March 21 projects real GDP growth in East Asia will be smaller than that of 2010 in the following two years.Besides future East Asian economic trends,the report also discusses the impact of the Japanese catastrophe.Edited excerpts follow:

  12. Mining in the European Arctic

    NARCIS (Netherlands)

    van Dam, Karin; Scheepstra, Adriana; Gille, Johan; Stepien, Adam; Koivurova, Timo; Stepien, Adam; Koivurova, Timo; Kankaanpää, Paula

    2016-01-01

    The European Arctic has been recently experiencing an upsurge in mining activities. This is reflected in an on-going interest from the industry, regulators and the public. However, current and future prospects are highly sensitive to mineral price fluctuations. The EU is a major consumer and importe

  13. Preface to the Special Issue on Geodynamic and Climate-Change Processes over Tibet, Xinjiang and Siberia

    Directory of Open Access Journals (Sweden)

    Cheinway Hwang

    2011-01-01

    Full Text Available Tibet, Xinjiang and Siberia (TibXS are regions with active plate tectonics. Evidence from satellite gravimetry and altimetry shows the hydrological evolutions over these regions are sensitive to global climate change. For example, inter-annual lake level changes over Tibet and Xinjiang from satellite altimetry are found to be connected to the El Nino Southern Oscillation (ENSO. Lakes in central Asia, Xinjiang and Siberia show sharp changes in lake levels that can be explained by climate change. Recent terrestrial gravity, GRACE and GPS observations suggest that the crust over the Tibetan plateau is thickening, and the Himalayan glaciers appear to be thinning. Satellite altimetry is a potential tool to study vertical displacement and permafrost thawing and changes in the active layers in Siberia and Tibet.

  14. Endurance of larch forest ecosystems in eastern Siberia under warming trends.

    Science.gov (United States)

    Sato, Hisashi; Kobayashi, Hideki; Iwahana, Go; Ohta, Takeshi

    2016-08-01

    The larch (Larix spp.) forest in eastern Siberia is the world's largest coniferous forest. Its persistence is considered to depend on near-surface permafrost, and thus, forecast warming over the 21st century and consequent degradation of near-surface permafrost is expected to affect the larch forest in Siberia. However, predictions of these effects vary greatly, and many uncertainties remain about land - atmosphere interactions within the ecosystem. We developed an integrated land surface model to analyze how the Siberian larch forest will react to current warming trends. This model analyzed interactions between vegetation dynamics and thermo-hydrology, although it does not consider many processes those are considered to affect productivity response to a changing climate (e.g., nitrogen limitation, waterlogged soil, heat stress, and change in species composition). The model showed that, under climatic conditions predicted under gradual and rapid warming, the annual net primary production of larch increased about 2 and 3 times, respectively, by the end of the 21st century compared with that in the previous century. Soil water content during the larch-growing season showed no obvious trend, even when surface permafrost was allowed to decay and result in subsurface runoff. A sensitivity test showed that the forecast temperature and precipitation trends extended larch leafing days and reduced water shortages during the growing season, thereby increasing productivity. The integrated model also satisfactorily reconstructed latitudinal gradients in permafrost presence, soil moisture, tree leaf area index, and biomass over the entire larch-dominated area in eastern Siberia. Projected changes to ecosystem hydrology and larch productivity at this geographical scale were consistent with those from site-level simulation. This study reduces the uncertainty surrounding the impact of current climate trends on this globally important carbon reservoir, and it demonstrates the need

  15. Dynamics of the larch taiga-permafrost coupled system in Siberia under climate change

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Ningning [Graduate School of Environmental Studies, Nagoya University, Nagoya, Aichi 464-8601 (Japan); Yasunari, Tetsuzo [Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya 464-8601 (Japan); Ohta, Takeshi, E-mail: zhangningning@lasg.iap.ac.cn [Study Consortium for Earth-Life Interactive Systems (SELIS) of Nagoya University, Nagoya (Japan)

    2011-04-15

    Larch taiga, also known as Siberian boreal forest, plays an important role in global and regional water-energy-carbon (WEC) cycles and in the climate system. Recent in situ observations have suggested that larch-dominated taiga and permafrost behave as a coupled eco-climate system across a broad boreal zone of Siberia. However, neither field-based observations nor modeling experiments have clarified the synthesized dynamics of this system. Here, using a new dynamic vegetation model coupled with a permafrost model, we reveal the processes of interaction between the taiga and permafrost. The model demonstrates that under the present climate conditions in eastern Siberia, larch trees maintain permafrost by controlling the seasonal thawing of permafrost, which in turn maintains the taiga by providing sufficient water to the larch trees. The experiment without permafrost processes showed that larch would decrease in biomass and be replaced by a dominance of pine and other species that suffer drier hydroclimatic conditions. In the coupled system, fire not only plays a destructive role in the forest, but also, in some cases, preserves larch domination in forests. Climate warming sensitivity experiments show that this coupled system cannot be maintained under warming of about 2 deg. C or more. Under such conditions, a forest with typical boreal tree species (dark conifer and deciduous species) would become dominant, decoupled from the permafrost processes. This study thus suggests that future global warming could drastically alter the larch-dominated taiga-permafrost coupled system in Siberia, with associated changes of WEC processes and feedback to climate.

  16. Fire Impact on Phytomass and Carbon Emissions in the Forests of Siberia

    Science.gov (United States)

    Ivanova, Galina A.; Zhila, Sergei V.; Ivanov, Valery A.; Kovaleva, Nataly M.; Kukavskaya, Elena A.; Platonova, Irina A.; Conard, Susan G.

    2014-05-01

    Siberian boreal forests contribute considerably to the global carbon budget, since they take up vast areas, accumulate large amount of carbon, and are sensitive to climatic changes. Fire is the main forest disturbance factor, covering up to millions of hectares of boreal forests annually, of which the majority is in Siberia. Carbon emissions released from phytomass burning influence atmospheric chemistry and global carbon cycling. Changing climate and land use influence the number and intensity of wildfires, forest state, and productivity, as well as global carbon balance. Fire effects on forest overstory, subcanopy woody layer, and ground vegetation phytomass were estimated on sites in light-conifer forests of the Central Siberia as a part of the project "The Influence of Changing Forestry Practices on the Effects of Wildfire and on Interactions Between Fire and Changing Climate in Central Siberia" supported by NASA (NEESPI). This study focuses on collecting quantitative data and modeling the influence of fires of varying intensity on fire emissions, carbon budget, and ecosystem processes in coniferous stands. Fires have a profound impact on forest-atmospheric carbon exchange and transform forests from carbon sinks to carbon sources lasting long after the time of burning. Our long-term experiments allowed us to identify vegetation succession patterns in taiga Scots pine stands after fires of known behavior. Estimating fire contributions to the carbon budget requires consideration of many factors, including vegetation type and fire type and intensity. Carbon emissions were found to depend on fire intensity and weather. In the first several years after fire, the above-ground phytomass appeared to be strongly controlled by fire intensity. However, the influence of burning intensity on organic matter accumulation was found to decrease with time.

  17. Effects of Repeated Fires in the Forest Ecosystems of the Zabaikalye Region, Southern Siberia

    Science.gov (United States)

    Kukavskaya, E.; Buryak, L. V.; Conard, S. G.; Petkov, A.; Barrett, K.; Kalenskaya, O. P.; Ivanova, G.

    2014-12-01

    Fire is the main ecological disturbance controlling forest development in the boreal forests of Siberia and contributing substantially to the global carbon cycle. The warmer and dryer climate observed recently in the boreal forests is considered to be responsible for extreme fire weather, resulting in higher fire frequency, larger areas burned, and an increase of fire severity. Because of the increase of fire activity, boreal forests in some regions may not be able to reach maturity before they re-burn, which means less carbon will be stored in the ecosystem and more will remain in the atmosphere. Moreover, if one fire occurs within a few years of another, some stands will not re-grow at all, and even more carbon will accumulate in the atmosphere. Zabaikalye region located in the south of Siberia is characterized by the highest fire activity in Russia. With a use of the satellite-based fire product we found that there are about 7.0 million hectares in the region burned repeatedly during the last decade. We have investigated a number of sites in-situ in light-coniferous (Scots pine and larch) forests and evaluated the impacts of repeated fires on fuel loads, carbon emissions, and tree regeneration. Substantial decrease of carbon stocks, change of the vegetation structure and composition, and soil erosion were observed in many areas disturbed by repeated fires. At drier sites located in the southern regions repeated fires prohibited successful regeneration and resulted in forest conversion to grassland. Detection and monitoring of changes in the areas of Siberia where repeated fires have caused a major shift in ecosystem structure and function is required for the development of sustainable forest management strategies to mitigate climate change. The research was supported by NASA LCLUC Program.

  18. Late Quaternary lake-level changes of Lake El'gygytgyn, NE Siberia

    OpenAIRE

    Juschus, O.; Pavlov, M.; G. Schwamborn; Preusser, F.; Fedorov, G.; Melles, M.

    2011-01-01

    Lake El'gygytgyn is situated in a 3.6 Ma old impact crater in northeastern Siberia. Presented here is a reconstruction of the Quaternary lake-level history as derived from sediment cores from the southern lake shelf. There, a cliff-like bench 10 m below the modern water level has been investigated. Deep-water sediments on the shelf indicate high lake levels during a warm Mid-Pleistocene period. One period with low lake level prior to Marine Oxygen Isotope Stage (MIS) 3 has been identified, fo...

  19. Reindeer pastoralism in modern Siberia: research and survival during the time of crash

    OpenAIRE

    Krupnik, Igor

    2000-01-01

    In many areas across Siberia, the reindeer herding economy of the native people went into a deep recession during the post-Soviet transition of the 1990s. However, as a larger cross-section of data indicates, the reindeer stock decline is not a universal phenomenon. Nor is the present-day crisis in native Siberian herding economies an unprecedented event, as pastoralists did suffer tremendously in “traditional times”, due to the devastating epizootics and other natural disasters, and even mor...

  20. [COMPARATIVE ANALYSIS OF TRACE ELEMENT COMPOSITION OF HAIR IN URBAN RESIDENTS OF WESTERN SIBERIA].

    Science.gov (United States)

    Vilms, E A; Gogadze, N V; Turchaninov, D V; Korchina, T Ya

    2015-01-01

    There was performed a study of the element status (hair analysis) of the population of the two cities of Western Siberia: Surgut (n = 350) and Omsk (n = 385). Detection of elements was performed by atomic emission and mass spectrometry methods. The population of Surgut when compared with residents of Omsk bioelements were characterized by a more high content of B, Cu, Co, Fe, Mg, I, Zn (p hair of Surgut residents in more higher concentrations there were detected toxic and potentially harmful elements such as Pb, Hg, Be, Cd, Li, Sn (p nutrition.

  1. Ozone vertical flux within the lower troposphere over background areas of west Siberia

    Science.gov (United States)

    Antokhin, P. N.; Antokhina, O. Yu.; Belan, S. B.; Belan, B. D.; Kozlov, A. V.; Krasnov, O. A.; Pestunov, D. A.

    2014-11-01

    In this paper the results of the vertical ozone flux profiles calculated within the lower troposphere over background area of west Siberia are presented. The data on the vertical distribution of the ozone and meteorological parameters derived from AN-2 aircraft measurements supplemented by radiosonde launches. Profiles of turbulent diffusion coefficient were calculated based on "K-theory" with the use of nonlocal closure scheme - "Troen and Mahrt". Calculations confirmed earlier findings that the formation of the daytime ozone maximum in the atmospheric boundary layer occurs due to its photochemical production from precursors.

  2. Application of the Terra Modis Satellite Data for Environmental Monitoring in Western Siberia

    Science.gov (United States)

    Yashchenkoa, I. G.; Peremitina, T. O.

    2016-06-01

    Using the MODIS thematic products, the status of vegetation of oil producing areas in Western Siberia for the period 2010-2015 is monitored. An approach for estimating the impact of various factors on the ecology of oil producing areas using the NDVI coefficient and remote sensing data on the status of vegetation is proposed. The approach is tested within four technologically-disturbed lands - four oil fields, Krapivinskoye, Myldzhenskoye, Luginetskoye, and Urmanskoye in Tomsk region. The territory of the Oglatsky Status Nature Reserve of regional importance is investigated as a reference area.

  3. Monitoring of iodine deficiency in Central Siberia according the results of neonatal TSHscreening

    OpenAIRE

    I V Osokina; D E Osokina; V. T. Manchouk

    2013-01-01

    The aim of the research was to estimate the iodine deficiency and the effectiveness of IDD prevention in Central Siberia according the results of neonatal TSHscreening. Methods. Screening for congenital hypothyroidism used as an indicator of the degree of iodine deficiency and of its control. We analyzed the neonatal TSH values of 34980 infants born in 2008–2009. Results. According to the data of the congenital hypothyroidism screening the rate of TSH < 5 mU/1 was 11.8% in the Krasnoyarsk ...

  4. Accounting for natural-climatic conditions in the design of roads in western Siberia

    Institute of Scientific and Technical Information of China (English)

    Vladimir N. Efimenko; Sergey V. Efimenko; Alexey V. Sukhorukov

    2015-01-01

    The paper proposes a methodological scheme that thoroughly accounts for natural-climatic conditions which can impair the stability and longevity of transport facilities (roadways), to ensure the best possible quality of the initial road design. Factors determining the formation of water-heating mode subgrade soils are allocated, and an information database for mathematical modeling of geocomplexes is shown. Values of strength and deformability of clay soils are calculated within the limits of the defined, homogeneous road districts in Western Siberia to provide the required level of reliability of design solutions.

  5. Optimizing the power of transformer substations in electric supply to the oil fields of Western Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Nissenbaum, I.A.; Kudryashov, R.A.; Novoselov, Yu.B.; Sud, I.N.

    1983-01-01

    The problems which come up in designing substations for electricity supply grids for the oil fields in Western Siberia in determining their capacity are examined. A technique is proposed for technical and economic selection of the capacity of substations with consideration of the specifications for design documentation. The issues of rating loads on transformer substations and their prediction are examined. A technique for considering the overloading capability of transformers and their wear at the design load is presented. An example of power drop of an oil field, 35/6 kilovolt voltage substation is cited.

  6. APPLICATION OF THE TERRA MODIS SATELLITE DATA FOR ENVIRONMENTAL MONITORING IN WESTERN SIBERIA

    Directory of Open Access Journals (Sweden)

    I. G. Yashchenkoa

    2016-06-01

    Full Text Available Using the MODIS thematic products, the status of vegetation of oil producing areas in Western Siberia for the period 2010-2015 is monitored. An approach for estimating the impact of various factors on the ecology of oil producing areas using the NDVI coefficient and remote sensing data on the status of vegetation is proposed. The approach is tested within four technologically-disturbed lands – four oil fields, Krapivinskoye, Myldzhenskoye, Luginetskoye, and Urmanskoye in Tomsk region. The territory of the Oglatsky Status Nature Reserve of regional importance is investigated as a reference area.

  7. Influence of global climatic processes on environment The Arctic seas

    Science.gov (United States)

    Kholmyansky, Mikhael; Anokhin, Vladimir; Kartashov, Alexandr

    2016-04-01

    One of the most actual problems of the present is changes of environment of Arctic regions under the influence of global climatic processes. Authors as a result of the works executed by them in different areas of the Russian Arctic regions, have received the materials characterising intensity of these processes. Complex researches are carried out on water area and in a coastal zone the White, the Barents, the Kara and the East-Siberian seas, on lake water areas of subarctic region since 1972 on the present. Into structure of researches enter: hydrophysical, cryological observations, direct measurements of temperatures, the analysis of the drill data, electrometric definitions of the parametres of a frozen zone, lithodynamic and geochemical definitions, geophysical investigations of boreholes, studying of glaciers on the basis of visual observations and the analysis of photographs. The obtained data allows to estimate change of temperature of a water layer, deposits and benthonic horizon of atmosphere for last 25 years. On the average they make 0,38⁰C for sea waters, 0,23⁰C for friable deposits and 0,72⁰C for atmosphere. Under the influence of temperature changes in hydrosphere and lithosphere of a shelf cryolithic zone changes the characteristics. It is possible to note depth increase of roof position of the cryolithic zone on the most part of the studied water area. Modern fast rise in temperature high-ice rocks composing coast, has led to avalanche process thermo - denudation and to receipt in the sea of quantity of a material of 1978 three times exceeding level Rise in temperature involves appreciable deviation borders of the Arctic glacial covers. On our monitoring measurements change of the maintenance of oxygen in benthonic area towards increase that is connected with reduction of the general salinity of waters at the expense of fresh water arriving at ice thawing is noticed. It, in turn, leads to change of a biogene part of ecosystem. The executed

  8. Geologic Provinces of the Circum-Arctic, 2008 (north of the Arctic Circle)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile includes arcs and polygons that describe U.S. Geological Survey defined 33 geologic provinces of the Circum-Arctic (north of the Arctic Circle). Each...

  9. 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.

  10. Strategic metal deposits of the Arctic Zone

    Science.gov (United States)

    Bortnikov, N. S.; Lobanov, K. V.; Volkov, A. V.; Galyamov, A. L.; Vikent'ev, I. V.; Tarasov, N. N.; Distler, V. V.; Lalomov, A. V.; Aristov, V. V.; Murashov, K. Yu.; Chizhova, I. A.; Chefranov, R. M.

    2015-11-01

    Mineral commodities rank high in the economies of Arctic countries, and the status of mineral resources and the dynamics of their development are of great importance. The growing tendency to develop strategic metal resources in the Circumarctic Zone is outlined in a global perspective. The Russian Arctic Zone is the leading purveyor of these metals to domestic and foreign markets. The comparative analysis of tendencies in development of strategic metal resources of the Arctic Zone in Russia and other countries is crucial for the elaboration of trends of geological exploration and research engineering. This paper provides insight into the development of Arctic strategic metal resources in global perspective. It is shown that the mineral resource potential of the Arctic circumpolar metallogenic belt is primarily controlled by large and unique deposits of nonferrous, noble, and rare metals. The prospective types of economic strategic metal deposits in the Russian Arctic Zone are shown.

  11. Evolution of the Arctic Calanus complex: an Arctic marine avocado?

    OpenAIRE

    Berge, Jørgen; Gabrielsen, Tove M.; Mark A Moline; Renaud, Paul

    2012-01-01

    Before man hunted the large baleen whales to near extinction by the end of the nineteenth century, Arctic ecosystems were strongly influenced by these large predators. Their main prey were zooplankton, among which the calanoid copepod species of the genus Calanus, long considered key elements of polar marine ecosystems, are particularly abundant. These herbivorous zooplankters display a range of adaptations to the highly seasonal environments of the polar oceans, most notably extensive energy...

  12. Arctic whaling : proceedings of the International Symposium Arctic Whaling February 1983

    NARCIS (Netherlands)

    Jacob, H.K. s'; Snoeijing, K

    1984-01-01

    Contents: D.M. Hopkins and Louie Marincovich Jr. Whale Biogeography and the history of the Arctic Basin P.M. Kellt, J.H.W. Karas and L.D. Williams Arctic Climate: Past, Present and Future Torgny E. Vinje On the present state and the future fate of the Arctic sea ice cover P.J.H. van Bree On the biol

  13. Arctic shipping emissions inventories and future scenarios

    OpenAIRE

    J. J. Corbett; D. A. Lack; J. J. Winebrake; Harder, S; J. A. Silberman; Gold, M.

    2010-01-01

    The Arctic is a sensitive region in terms of climate change and a rich natural resource for global economic activity. Arctic shipping is an important contributor to the region's anthropogenic air emissions, including black carbon – a short-lived climate forcing pollutant especially effective in accelerating the melting of ice and snow. These emissions are projected to increase as declining sea ice coverage due to climate change allows for increased shipping activity in the Arctic. To understa...

  14. Arctic cephalopod distributions and their associated predators

    OpenAIRE

    Gardiner, Kathleen; Terry A Dick

    2010-01-01

    Cephalopods are key species of the eastern Arctic marine food web, both as prey and predator. Their presence in the diets of Arctic fish, birds and mammals illustrates their trophic importance. There has been considerable research on cephalopods (primarily Gonatus fabricii) from the north Atlantic and the west side of Greenland, where they are considered a potential fishery and are taken as a by-catch. By contrast, data on the biogeography of Arctic cephalopods are still incomplete. This stud...

  15. Shaping a Sustainability Strategy for the Arctic

    OpenAIRE

    Azcarate, Juan; Balfors, Berit; Destouni, Georgia; Bring, Arvid

    2011-01-01

    The development of the Arctic is shaped by the opportunities and constraints brought by climate change and technological advances. In the Arctic, warmer climate is expected to affect ecosystems, local communities and infrastructure due to a combination of effects like reduced sea ice and glaciers, thawing permafrost and increased frequency of floods. Less ice and new technologies mean openings to exploit natural resources in the Arctic. Fishing, mining, hydrocarbon extraction and vessel trans...

  16. Fine-resolution simulation of surface current and sea ice in the Arctic Mediterranean Seas

    Institute of Scientific and Technical Information of China (English)

    LIU Xiying; ZHANG Xuehong; YU Rucong; LIU Hailong; LI Wei

    2007-01-01

    A fine-resolution model is developed for ocean circulation simulation in the National Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG),Chinese Academy of Sciences, and is applied to simulate surface current and sea ice variations in the Arctic Mediterranean Seas. A dynamic sea ice model in elastic-viscous-plastic rheology and a thermodynamic sea ice model are employed. A 200-year simulation is performed and a dimatological average of a 10-year period (141 st-150 th) is presented with focus on sea ice concentration and surface current variations in the Arctic Mediterranean Seas. The model is able to simulate well the East Greenland Current, Beaufort Gyre and the Transpolar Drift, but the simulated West Spitsbergen Current is small and weak. In the March climatology, the sea ice coverage can be simulated well except for a bit more ice in east of Spitsbergen Island. The result is also good for the September scenario except for less ice concentration east of Greenland and greater ice concentration near the ice margin. The extra ice east of Spitsbergen Island is caused by sea ice current convergence forced by atmospheric wind stress.

  17. Monitoring of iodine deficiency in Central Siberia according the results of neonatal TSHscreening

    Directory of Open Access Journals (Sweden)

    I V Osokina

    2013-06-01

    Full Text Available The aim of the research was to estimate the iodine deficiency and the effectiveness of IDD prevention in Central Siberia according the results of neonatal TSHscreening. Methods. Screening for congenital hypothyroidism used as an indicator of the degree of iodine deficiency and of its control. We analyzed the neonatal TSH values of 34980 infants born in 2008–2009. Results. According to the data of the congenital hypothyroidism screening the rate of TSH < 5 mU/1 was 11.8% in the Krasnoyarsk territory (23.9% in 2000 and corresponded to mild iodine deficiency. In different regions of the Krasnoyarsk territory the rate of TSH < 5 mU/1 in the newborn varied from 3.5% to 23.7%. The highest values were marked in the Taimyr, in Irbeysky, Suchobuzimsky, Eniseysky, Tuchtetsky, Novoselovsky regions, in Zheleznogorsk and Sosnovoborsk city (20.9–23.7%. In Khakasia the rate of TSH < 5 mU/1 was 12.2%. In the Republic of Tyva – 6.6% (38.6% in 1997; 11.5% in 2000. It corresponding to mild iodine deficie ncy. Conclusion. Our investigations show that in Central Siberia there is mild iodine deficiency demanding continuous adequate iodine prevention.

  18. Phosphorus status of soils from contrasting forested ecosystems in southwestern Siberia

    Science.gov (United States)

    Achat, D. L.; Bakker, M. R.; Zeller, B.; Derrien, D.; Barsukov, P.; Nikitich, P.

    2011-12-01

    Phosphorus is one of the most limiting nutrients in many ecosystems and mineral reserves available for fertilizer production are forecasted to last for no more than 100 yrs. Crop requirements for P are often lower in forests than in agriculture and P fertilization to forest ecosystems is not very common on a global scale. In southern Siberia, expected climate change would lead to higher overall precipitation, higher temperatures and subsequently to changes in land use (i.e. agricultural land could increase on detriment of forests). In the present work we evaluated P status in four forested ecosystems in southwestern Siberia including 1 site with lowland Populus tremula, and 3 upland sites in the Salair mountains with Populus tremula, Abies siberica or with small forest openings. The upland sites feature twice higher productivity than the lowland sites and it was suggested that thick snow cover on those sites would enable winter activity of microbial communities leading to faster soil degradation processes and higher nutrient availability. We thus wanted to test whether biological processes in the upland sites were of larger impact on P status than in the lowland sites. We combined 32P isotopic dilution techniques (for diffusive P), chemical extractions (for total P, organic P) and fumigation/incubation/respiration methods (for microbial P) to test this hypothesis. Additional soil analyses (C, N and othes) were performed. Results will be interpreted in the light of the exising knowledge on botany, climate, pedology and expected implications for future land use, would this occur to change.

  19. Saturated hydrocarbon biomarkers in oils of Late Precambrian age from Eastern Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.G.; Douglas, A.G.

    1987-01-01

    Large quantities of petroleum derived from source rocks of Late Precambrian-Early Cambrian age have been discovered in the Lena-Tunguska region of Eastern Siberia over the last twenty-five years. The authors have examined three oils, with presumed Late-Precambrian (Vendian) source rocks, from this region for C/sub 15/ + saturated hydrocarbon biomarkers using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The results show these oils to have many characteristics in common with other oils of similar age from Eastern Siberia and Oman. Amongst the compounds detected in the three oils analyzed were: (1) n-alkanes which show a marine-derived distribution, (2) centrally branched monomethyl alkanes, (3) acyclic isoprenoids (pr/ph < 1), (4) tricyclic and tetracyclic terpanes, (5) hopanes, (6) C/sub 29/ unrearranged steranes, and (7) C/sub 30/ nuclear methylated steranes. All of these compounds with the exception of the 4-methylsteranes (which on current biochemical knowledge are unexpected in oils of this age), can be assigned a prokaryotic source. This and other evidence such as the lack of diasteranes suggest microorganisms were the major contributors to organic matter deposited as part of a carbonate source rock.

  20. The Voivode Government’s Genesis in Siberia: a Study of Key Aspects

    Directory of Open Access Journals (Sweden)

    Yakov G. Solodkin

    2015-03-01

    Full Text Available The voivode system of government emerged in Western Siberia at the turn of the 16th–17th centuries, following the legendary expedition of Yermak’s Cossacks. Its implementation depended crucially on the succession in which the Russian acquisition of the new vast territories had taken place. Voivodes and departmental administrators usually acted as county governors as the counties were formed around towns, with stockaded settlements shaping the scope of responsibility of departmental administrators, whose status and functions have often created considerable confusion in Russian historiography, inasmuch as they are frequently but groundlessly identified with voivodes, with the latter’s functions sometimes attributed to streltsy commanders or even Cossack atamans. In the early period of the Russian colonization of Siberia, as well as in the subsequent years, it was standard practice to send to the newly acquired lands voivodes and departmental administrators who possessed extensive experience in governance. The practice of Intra-Siberian transferring of departmental administrators, which gained wide currency in the 17th century, had been adopted well before 1599, the year when the Tobolsk department was established. In most cases, the officers who founded towns and stockaded settlements served a one-year term of appointment, with the latter being occasionally extended to two or three years.

  1. Arctic tides from GPS on sea ice

    DEFF Research Database (Denmark)

    Kildegaard Rose, Stine; Skourup, Henriette; Forsberg, René

    The presence of sea-ice in the Arctic Ocean plays a significant role in the Arctic climate. Sea ice dampens the ocean tide amplitude with the result that global tidal models which use only astronomical data perform less accurately in the polar regions. This study presents a kinematic processing...... of Global Positioning System (GPS) buoys placed on sea-ice at five different sites north of Greenland for the study of sea level height and tidal analysis to improve tidal models in the Central Arctic. The GPS measurements are compared with the Arctic tidal model AOTIM-5, which assimilates tide...

  2. Rossby Waves in the Arctic Ocean

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Schmith, Torben

    The Arctic Ocean has a characteristic stable stratification with fresh and cold water occupying the upper few hundred meters and the warm and more saline Atlantic waters underneath. These water masses are separated by the cold halocline. The stability of the cold halocline regulates the upward...... directed turbulent heat flux from the Atlantic water to the Arctic water. This heat flux is a part of the arctic energy budget and is important for large scale sea ice formation and melting. Due to the strong vertical stratification combined with its almost circular boundary, the Arctic Ocean supports...

  3. Plate tectonic history of the Arctic

    Science.gov (United States)

    Burke, K.

    1984-01-01

    Tectonic development of the Arctic Ocean is outlined, and geological maps are provided for the Arctic during the mid-Cenozoic, later Cretaceous, late Jurassic, early Cretaceous, early Jurassic and late Devonian. It is concluded that Arctic basin history is moulded by the events of the following intervals: (1) continental collision and immediately subsequent rifting and ocean formation in the Devonian, and continental rifting ocean formation, rapid rotation of microcontinents, and another episode of collision in the latest Jurassic and Cretaceous. It is noted that Cenozoic Arctic basin formation is a smaller scale event superimposed on the late Mesozoic ocean basin.

  4. LA-ICP-MS analysis of trace elements in glass spherules of the El'gygytgyn impact structure, Siberia

    Science.gov (United States)

    Adolph, Leonie; Deutsch, Alex

    2010-05-01

    The 3.58±0.04 Ma old El'gygytgyn impact structure (Central Chukotka, NE Siberia) with a diameter of 18 km (Gurov and Gurova 1979, Layer 2000) is one of only two terrestrial craters with a volcanic target; therefore, analysis of its target and impact lithologies is of basic interest for comparative planetology. Lake El'gygytgyn is a very valuable climate archive in the Arctic as it was neither covered by glaciers (Melles et al. 2007) nor has the lake ever fallen dry. Climate and impact research were the rationale for the ICDP drilling project that finished successfully in spring 2009. Impactites like melt rocks and breccias are rarely found in outcrops yet are present in the 80 m terrace of Lake El'gygytgyn (Gurov and Gurova 1979). Numerous investigations on petrography, shock metamorphism, and geochemistry of impactites from El'gygytgyn have been published so far (e.g. Gurov et al. 2007). We report the first trace element data for seven 30- to 760-μm-sized impact glass spherules that have been collected about10 km off the crater center from a terrace deposit of the Enmyvaam River outside the crater rim. The spherules are translucent with colors ranging from amber, dark brown to nearly black; they contain a few circular bubbles, schlieren, and very rarely mineral clasts and breccia fragments. Major elements were measured with the JEOL JXA 8600 MX Superprobe, 31 trace elements were analyzed with the Finnigan Element2 LA-ICP-MS with 5 Hz, 8-9 J/cm2 at with Si as internal, and NIST612 as external standard (Institut f. Mineralogie, WWU Münster). The spot size was 60 μm. All spherules show a very homogeneous major and trace element distribution yet clear differences exist between the samples in the SiO2 content (in weight percent) 53-68: four of the glasses are dacitic, two andesitic, and one basaltic-andesitic in composition. In addition, MgO (2.1-9.2), K2O (0.6-3.3), and (in ppm) Ni (317-1096), Co (25-79), Zr (100-169), Rb (18-107), and Ba (459-1092) display wide

  5. Arctic Basemaps In Google Maps

    DEFF Research Database (Denmark)

    Muggah, J.; Mioc, Darka

    2010-01-01

    the advantages of the use of Google Maps, to display the OMG's Arctic data. The map should should load the large Artic dataset in a reasonable time. The bathymetric images were created using software in Linux written by the OMG, and a step-by-step process was used to create images from the multibeam data...... collected by the OMG in the Arctic. The website was also created using Linux operating system. The projection needed to be changed from Lambert Conformal Conic (useful at higher Latitudes) to Mercator (used by Google Maps) and the data needed to have a common colour scheme. After creating and testing...... a prototype website using Google Ground overlay and Tile overlay, it was determined that the high resolution images (10m) were loading very slowly and the ground overlay method would not be useful for displaying the entire dataset. Therefore the Tile overlays were selected to be used within Google Maps. Tile...

  6. Aerosols indirectly warm the Arctic

    Directory of Open Access Journals (Sweden)

    T. Mauritsen

    2010-07-01

    Full Text Available On average, airborne aerosol particles cool the Earth's surface directly by absorbing and scattering sunlight and indirectly by influencing cloud reflectivity, life time, thickness or extent. Here we show that over the central Arctic Ocean, where there is frequently a lack of aerosol particles upon which clouds may form, a small increase in aerosol loading may enhance cloudiness thereby likely causing a climatologically significant warming at the ice-covered Arctic surface. Under these low concentration conditions cloud droplets grow to drizzle sizes and fall, even in the absence of collisions and coalescence, thereby diminishing cloud water. Evidence from a case study suggests that interactions between aerosol, clouds and precipitation could be responsible for attaining the observed low aerosol concentrations.

  7. Stories from the Arctic field

    Science.gov (United States)

    Cain, Michelle

    2016-04-01

    I will discuss my experience co-ordinating a range of communication activities for a multi-university research programme called Methane in the Arctic: Measurements and Modelling. The project included ground- and aircraft-based fieldwork in the European Arctic, as well as computer modelling. Our communication activities included: our own field blog (www.arcticmethane.wordpress.com), which was syndicated to the Scientific American Expeditions blog; writing articles for other blogs with a wider audience than our own; use of twitter; and podcasting our field work. The grand finale to our communications work was a live event at a science festival, in which we took the audience along with us on a recreated research flight, complete with a life-size mock up of a section of our research aircraft. I will discuss my experiences of these forms of communication, and give an evaluation of their successes and failures.

  8. Spatial variability of carbon (δ13C) and nitrogen (δ15N) stable isotope ratios in an Arctic marine food web

    DEFF Research Database (Denmark)

    Hansen, Joan Holst; Hedeholm, Rasmus Berg; Sünksen, Kaj;

    2012-01-01

    Stable isotopes of carbon (δ13C) and nitrogen (δ15N) were used to examine trophic structures in an arctic marine food web at small and large spatial scales. Twelve species, from primary consumers to Greenland shark, were sampled at a large spatial scale near the west and east coasts of Greenland...

  9. Aliphatic side chains of proteins as potential geomarkers of NOM liberated from the melting permafrost and discharged to the Arctic Ocean by the Kolyma River run off

    Science.gov (United States)

    Dubinenkov, I. V.; Perminova, I.; Kononikhin, A.; Nikolaev, E.; Hertkorn, N.; Bulygina, E. B.; Holmes, R. M.

    2011-12-01

    , etc). Mobilization of much more bioavailable pool of organic compounds such as peptides, which were found in the permafrost samples might affect substantially carbon cycling in the region and in the Arctic Ocean. Further understanding of carbon turnover in the Arctic region on the molecular level is needed to predict the possible consequences of massive permafrost thaw for the global climate change and reveal the reliable geomarkers of this process. This can be achieved with a combined use of NMR and FTICRMS spectroscopic techniques possessing unprecedented resolution power for investigation of complex mixtures.. Acknowledgement. This study is part of the Polaris Project, an NSF-funded undergraduate field program based out of the Northeast Science Station in Cherskiy, Northeast Siberia (www.thepolarisproject.org). The research was supported by CRDF-RFBR Grant 09-03-92500 and Travel Grant of IHSS allocated in 2011 to Ivan Dubinenkov.

  10. The Arctic Research Consortium of the United States (ARCUS): Connecting Arctic Research

    Science.gov (United States)

    Rich, R. H.; Wiggins, H. V.; Creek, K. R.; Sheffield Guy, L.

    2015-12-01

    This presentation will highlight the recent activities of the Arctic Research Consortium of the United States (ARCUS) to connect Arctic research. ARCUS is a nonprofit membership organization of universities and institutions that have a substantial commitment to research in the Arctic. ARCUS was formed in 1988 to serve as a forum for planning, facilitating, coordinating, and implementing interdisciplinary studies of the Arctic; to act as a synthesizer and disseminator of scientific information on arctic research; and to educate scientists and the general public about the needs and opportunities for research in the Arctic. ARCUS, in collaboration with the broader science community, relevant agencies and organizations, and other stakeholders, coordinates science planning and educational activities across disciplinary and organizational boundaries. Examples of ARCUS projects include: Arctic Sea Ice Outlook - an international effort that provides monthly summer reports synthesizing community estimates of the expected sea ice minimum. Sea Ice for Walrus Outlook - a resource for Alaska Native subsistence hunters, coastal communities, and others that provides weekly reports with information on sea ice conditions relevant to walrus in Alaska waters. PolarTREC (Teachers and Researchers Exploring and Collaborating) - a program whereby K-12 educators and researchers work together in hands-on field experiences in the Arctic and Antarctic to advance polar science education. ArcticInfo mailing list, Witness the Arctic newsletter, and the Arctic Calendar - communication tools for the arctic science community to keep apprised of relevant news, meetings, and announcements. Coordination for the Study of Environmental Arctic Change (SEARCH) program, which aims to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. More information about these and other ARCUS activities can be found at the ARCUS website at

  11. Building Materials in Arctic Climate

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    2005-01-01

    Building in the artic requires special attention on the appropriateness of building materials. The harsh climate makes execution difficult and sets unusual requirements for the pure material properties. In addition, there is a lack of choice of good, natural building materials in the arctic....... This results in high transport costs. The building materials situation in Greenland may potentially be improved by intensifying the reuse of building materials or by promoting the local production of building materials....

  12. Holocene climate change in Arctic Canada and Greenland

    Science.gov (United States)

    Briner, Jason P.; McKay, Nicholas P.; Axford, Yarrow; Bennike, Ole; Bradley, Raymond S.; de Vernal, Anne; Fisher, David; Francus, Pierre; Fréchette, Bianca; Gajewski, Konrad; Jennings, Anne; Kaufman, Darrell S.; Miller, Gifford; Rouston, Cody; Wagner, Bernd

    2016-09-01

    This synthesis paper summarizes published proxy climate evidence showing the spatial and temporal pattern of climate change through the Holocene in Arctic Canada and Greenland. Our synthesis includes 47 records from a recently published database of highly resolved Holocene paleoclimate time series from the Arctic (Sundqvist et al., 2014). We analyze the temperature histories represented by the database and compare them with paleoclimate and environmental information from 54 additional published records, mostly from datasets that did not fit the selection criteria for the Arctic Holocene database. Combined, we review evidence from a variety of proxy archives including glaciers (ice cores and glacial geomorphology), lake sediments, peat sequences, and coastal and deep-marine sediments. The temperature-sensitive records indicate more consistent and earlier Holocene warmth in the north and east, and a more diffuse and later Holocene thermal maximum in the south and west. Principal components analysis reveals two dominant Holocene trends, one with early Holocene warmth followed by cooling in the middle Holocene, the other with a broader period of warmth in the middle Holocene followed by cooling in the late Holocene. The temperature decrease from the warmest to the coolest portions of the Holocene is 3.0 ± 1.0 °C on average (n = 11 sites). The Greenland Ice Sheet retracted to its minimum extent between 5 and 3 ka, consistent with many sites from around Greenland depicting a switch from warm to cool conditions around that time. The spatial pattern of temperature change through the Holocene was likely driven by the decrease in northern latitude summer insolation through the Holocene, the varied influence of waning ice sheets in the early Holocene, and the variable influx of Atlantic Water into the study region.

  13. Ancient DNA analysis of the oldest canid species from the Siberian Arctic and genetic contribution to the domestic dog.

    Directory of Open Access Journals (Sweden)

    Esther J Lee

    Full Text Available Modern Arctic Siberia provides a wealth of resources for archaeological, geological, and paleontological research to investigate the population dynamics of faunal communities from the Pleistocene, particularly as the faunal material coming from permafrost has proven suitable for genetic studies. In order to examine the history of the Canid species in the Siberian Arctic, we carried out genetic analysis of fourteen canid remains from various sites, including the well-documented Upper Paleolithic Yana RHS and Early Holocene Zhokhov Island sites. Estimated age of samples range from as recent as 1,700 years before present (YBP to at least 360,000 YBP for the remains of the extinct wolf, Canis cf. variabilis. In order to examine the genetic affinities of ancient Siberian canids species to the domestic dog and modern wolves, we obtained mitochondrial DNA control region sequences and compared them to published ancient and modern canid sequences. The older canid specimens illustrate affinities with pre-domestic dog/wolf lineages while others appear in the major phylogenetic clades of domestic dogs. Our results suggest a European origin of domestic dog may not be conclusive and illustrates an emerging complexity of genetic contribution of regional wolf breeds to the modern Canis gene pool.

  14. New view on tectonic structure of Siberian Sector of the Amerasian Basin (Arctic Ocean)

    Science.gov (United States)

    Vinokurov, Yu. I.

    2014-05-01

    In 2012, JSC Sevmorgeo with assistance of several research institutions of Federal Agency of Mineral Resources (Rosnedra) and Ministry of Defense carried out a unique set of offshore seismic and geological studies in the Mendeleev Rise area and adjacent areas of the Amerasia Basin. Two specially re-equipped icebreakers ("Kapitan Dranitsin" and "Dixon") were used in this campaign. The main results of the expedition were 5315 km of multichannel seismic profiles both with long and short streamers (4500 m and 600 m, respectively), 480 km long refraction profile crossing Mendeleev Rise. Seismic acquisition with short streamers was accompanied by deployment of sonobuoys. Geological studies included deep-water drilling and sea-bottom sampling by dredge, gravity corer, grab and by specially equipped research submarine. The newly acquired geological and geophysical data allowed for the following conclusions: 1. The Mendeleev Rise, the adjacent Lomonosov Ridge and Chukchi Plateau are the direct continuations of the East Siberian Sea tectonic structures. It is confirmed by direct tracking of some morphostructures, faults, gravity and magnetic anomalies from the shelf to deep-water highs. 2. The East Arctic Shelf and the adjacent Arctic Ocean represent offshore extent of the Verkhoyansk-Kolyma crustal domain constituted by a mosaic of separate blocks of the Pre-Cambrian basement (Okhotsk, Omulevka, Omolon, Wrangel-Gerald and Central Arctic) and Late Mesozoic orogens. This area differs significantly from the Ellesmerian crustal domain located to the east (including the Northwind Ridge, which coincides with inferred eastern boundary of the Mesozoides). The Central Arctic domain includes structures of the Mendeleev Ridge and the Chukchi Plateau. Western boundary of this block is inferred along the Spur of Geophysicists, which separates the Podvodnikov Basin into two unequal parts with different basement structure. From the south, southwest and west, the Central Arctic domain is

  15. Assessment of Undiscovered Oil and Gas Resources of the West Greenland-East Canada Province, 2008

    Science.gov (United States)

    Schenk, Christopher J.; Bird, Kenneth J.; Brown, Philip J., II; Charpentier, Ronald R.; Gautier, Donald L.; Houseknecht, David W.; Klett, Timothy R.; Pawlewicz, Mark J.; Shah, Anjana; Tennyson, Marilyn E.

    2008-01-01

    The U.S. Geological Survey (USGS) recently assessed the undiscovered oil and gas potential of the West Greenland?East Canada Province as part of the USGS Circum-Arctic Oil and Gas Resource Appraisal effort. The West Greenland?East Canada Province is essentially the offshore area between west Greenland and east Canada and includes Baffin Bay, Davis Strait, Lancaster Sound, and Nares Strait west of and including Kane Basin. The tectonic evolution of the West Greenland?East Canada Province led to the formation of several major structural domains that are the geologic basis for the five assessment units (AU) defined in this study. The five AUs encompass the entire province. Each AU was assessed in its entirety for undiscovered, technically recoverable (assuming absence of sea ice) oil and gas resources, but the assessment results reported here are only for those portions of each AU that are north of the Arctic Circle, as that latitude defines the area of the Circum-Arctic oil and gas assessment.

  16. Arctic whaling: proceedings of the International Symposium Arctic Whaling February 1983

    OpenAIRE

    H.K. 's Jacob; Snoeijing, K

    1984-01-01

    Contents: D.M. Hopkins and Louie Marincovich Jr. Whale Biogeography and the history of the Arctic Basin P.M. Kellt, J.H.W. Karas and L.D. Williams Arctic Climate: Past, Present and Future Torgny E. Vinje On the present state and the future fate of the Arctic sea ice cover P.J.H. van Bree On the biology of whales Edward Mitchell Ecology of North Atlantic Boreal and Arctic Monodontid and Mysticete Whales Allen P. McCartney History of native whaling in the Arctic and Subarctic Albert A. Dekin Jr...

  17. Experience and Perspectives of Art History Development in Educational Space of Siberia at the Turn of XX-XXI ?enturies

    Science.gov (United States)

    Nekhvyadovich, Larisa Ivanovna; Chernyaeva, Irina Valerievna

    2016-01-01

    The article has a program-analytical nature, contains an analysis and assessment of the scientific school of T. M. Stepanskaya, Doctor of Arts, professor, member of Russian Union of Artists. The goal of T. M. Stepanskaya's professional activity is incorporation of Art History in higher educational institutions in Siberia. The authors consider the…

  18. Understanding the mechanisms of blooming of phytoplankton in Lake Shira, a saline lake in Siberia (the Republic of Khakasia)

    NARCIS (Netherlands)

    Degermendzhy, A.G.; Gulati, R.D.

    2002-01-01

    The paper summarises the results of a three-year research study (European Union Grant: INTAS 97-O519) aimed at investigating the planktonic populations and trophic organization of the Lake Shira ecosystem – a saline lake in Khakasia, Siberia. The lake exhibits a stable summer-autumn stratification o

  19. Variation characteristics of carbon monoxide and ozone over the course of the 2014 Chinese National Arctic Research Expedition

    Institute of Scientific and Technical Information of China (English)

    LI Bokun; BIAN Lingen; ZHENG Xiangdong; DING Minghu; XIE Zhouqing

    2015-01-01

    The concentrations of carbon monoxide and ozone in the marine boundary layer were measured during the 6th Chinese National Arctic Research Expedition (from July to September, 2014). Carbon monoxide concentration ranged between 47.00 and 528.52 ppbv with an average of 103.59 ± 40.37 ppbv. A slight decrease with increasing latitude was observed, except for the extremely high values over the East China Sea which may be attributed to anthropogenic emissions. Ozone concentration ranged between 3.27 and 77.82 ppbv with an average of 29.46±10.48 ppbv. Ozone concentration decreased sharply with increasing latitude outside the Arctic Ocean (during both the northward and the southward course), while no significant variation was observed over the Arctic Ocean. The positive correlation between carbon monoxide and ozone in most sections suggests that the ozone in the marine boundary layer mainly originated from photochemical reactions involving carbon monoxide.

  20. Intercomparison of atmospheric reanalysis data in the Arctic region: To derive site-specific forcing data for terrestrial models

    Science.gov (United States)

    Mori, J.; Saito, K.; Machiya, H.; Yabuki, H.; Ikawa, H.; Ohta, T.; Iijima, Y.; Kotani, A.; Suzuki, R.; Miyazaki, S.; Sato, A.; Hajima, T.; Sueyoshi, T.

    2015-12-01

    An intercomparison project for the Arctic terrestrial (physical and ecosystem) models, GTMIP, is conducted, targeting at improvements in the existing terrestrial schemes, as an activity of the Terrestrial Ecosystem research group in the Arctic of Japan GRENE Arctic Climate Change Research Project (GRENE-TEA). For site simulations for four GRENE-TEA sites (i.e., Fairbanks/AK, Kevo/Finland, Tiksi and Yakutsk/Siberia), we needed to prepare continuous, site-fit forcing data ready to drive the models. Due to scarcity of site observations in the region, however, it was difficult to make such data directly from the observations. Therefore, we decided to create a backbone dataset (Level 0 or Lv0) first by utilizing the reanalysis data to derive the site-specific data (Level 1 or Lv1). For selection of the best dataset for our purpose, we compared four atmospheric reanalysis datasets, i.e., ERA Interim, JRA-55, NCEP/NCAR Reanalysis 1, and NCEP-DOE Reanalysis 2, in terms of the climatic reproducibility (w.r.t. temperature at 2 m and precipitation) in the region north of 60°N. CRU for temperature and GPCP for precipitation were also used for monthly-mean ground-level climate. As we will show ERA-Interim showed the smallest bias for both the parameters in terms of RMSE. Especially, air temperature in the cold period was reproduced better in ERA-Interim than is in JRA-55 or other reanalysis products. Therefore, we created Lv0 from ERA-Interim. Comparison between the site observations and Lv0 showed good agreement except for wind speed at all sites and air temperature at Tiksi, a coastal site in the eastern Siberia. Air temperature of ERA-Interim showed significantly continental characteristics while the site observation more coastal. The 34-year-long, hourly, site-fit continuous data (Lv1) for each of the GRENE-TEA sites was then created from the Lv0 values at the grid point closest to the site, by merging with the observations.

  1. Relating Regional Arctic Sea Ice and climate extremes over Europe

    Science.gov (United States)

    Ionita-Scholz, Monica; Grosfeld, Klaus; Lohmann, Gerrit; Scholz, Patrick

    2016-04-01

    The potential increase of temperature extremes under climate change is a major threat to society, as temperature extremes have a deep impact on environment, hydrology, agriculture, society and economy. Hence, the analysis of the mechanisms underlying their occurrence, including their relationships with the large-scale atmospheric circulation and sea ice concentration, is of major importance. At the same time, the decline in Arctic sea ice cover during the last 30 years has been widely documented and it is clear that this change is having profound impacts at regional as well as planetary scale. As such, this study aims to investigate the relation between the autumn regional sea ice concentration variability and cold winters in Europe, as identified by the numbers of cold nights (TN10p), cold days (TX10p), ice days (ID) and consecutive frost days (CFD). We analyze the relationship between Arctic sea ice variation in autumn (September-October-November) averaged over eight different Arctic regions (Barents/Kara Seas, Beaufort Sea, Chukchi/Bering Seas, Central Arctic, Greenland Sea, Labrador Sea/Baffin Bay, Laptev/East Siberian Seas and Northern Hemisphere) and variations in atmospheric circulation and climate extreme indices in the following winter season over Europe using composite map analysis. Based on the composite map analysis it is shown that the response of the winter extreme temperatures over Europe is highly correlated/connected to changes in Arctic sea ice variability. However, this signal is not symmetrical for the case of high and low sea ice years. Moreover, the response of temperatures extreme over Europe to sea ice variability over the different Arctic regions differs substantially. The regions which have the strongest impact on the extreme winter temperature over Europe are: Barents/Kara Seas, Beaufort Sea, Central Arctic and the Northern Hemisphere. For the years of high sea ice concentration in the Barents/Kara Seas there is a reduction in the number

  2. Cold loving methanotrophic communities in permafrost soils of the Lena Delta, Siberia

    OpenAIRE

    Liebner, S.; Wagner, Dirk

    2005-01-01

    Wet tundra environments of the Siberian Artic are considerable natural sources of methane, a climate relevant trace gas. The Arctic is observed to warm more rapidly and to a greater extend than the rest of the earth surface. It is suggested, that the tundra in Alaska and Russia has changed from a net sink to a net source of atmospheric carbon. The potential impact on the Arctic carbon reservoirs is highly influenced by changes in microbial processes like methanogenesis and methane oxidation.T...

  3. October Cloud Increases Over the Arctic Ocean as Observed by MISR and CALIPSO

    Science.gov (United States)

    Wu, Dong L.; Lee, Jae N.

    2011-01-01

    The Beaufort and East Siberian Sea (BESS) shows a large increase in surface air temperature (SAT) in the recent decade for months of Sep-Nov, and NASA's Terra satellite have provided valuable measurements for this important decade of the intensified Arctic warming. In particular, MISR data since 2000 and CALIPSO cloud measurements since 2006 reveal a significant increase of low cloud cover in October, which is largest in the daylight Arctic months (March-October). Causes of the warming remain unclear; but increased absorption of summer solar radiation and autumn low cloud formation have been suggested as a positive ice-temperature-cloud feedback in the Arctic. The observed increase of low cloud cover supports the theorized positive ice-temperature-cloud feedback, whereby more open water in the Arctic Ocean increases summer absorption of solar radiation, and subsequent evaporation, which leads to more low clouds in autumn. Trapping longwave radiation, these clouds effectively lengthen the melt season and reduce perennial ice pack formation, making sea ice more vulnerable to the next melt season

  4. U.S. Geological Survery Oil and Gas Resource Assessment of the Russian Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Donald Gautier; Timothy Klett

    2008-12-31

    The U.S. Geological Survey (USGS) recently completed a study of undiscovered petroleum resources in the Russian Arctic as a part of its Circum-Arctic Resource Appraisal (CARA), which comprised three broad areas of work: geological mapping, basin analysis, and quantitative assessment. The CARA was a probabilistic, geologically based study that used existing USGS methodology, modified somewhat for the circumstances of the Arctic. New map compilation was used to identify assessment units. The CARA relied heavily on geological analysis and analog modeling, with numerical input consisting of lognormal distributions of sizes and numbers of undiscovered accumulations. Probabilistic results for individual assessment units were statistically aggregated, taking geological dependencies into account. The U.S. Department of Energy (DOE) funds were used to support the purchase of crucial seismic data collected in the Barents Sea, East Siberian Sea, and Chukchi Sea for use by USGS in its assessment of the Russian Arctic. DOE funds were also used to purchase a commercial study, which interpreted seismic data from the northern Kara Sea, and for geographic information system (GIS) support of USGS mapping of geological features, province boundaries, total petroleum systems, and assessment units used in the USGS assessment.

  5. Middle East Respiratory Syndrome

    Centers for Disease Control (CDC) Podcasts

    2014-07-07

    This podcast discusses Middle East Respiratory Syndrome, or MERS, a viral respiratory illness caused by Middle East Respiratory Syndrome Coronavirus—MERS-CoV.  Created: 7/7/2014 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 7/7/2014.

  6. Recovery in the East

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    As robust as the economic recovery in East Asia has been in recent months,attention must now be turned to managing emerging risks challenging macroeconomic stability,said World Bank’s latest East Asia and Pacific Economic Update released on October 19.Edited excerpts follow

  7. Factors promoting larch dominance in Eastern Siberia: fire versus growth performance and implications for carbon dynamics

    Directory of Open Access Journals (Sweden)

    E.-D. Schulze

    2012-01-01

    Full Text Available The relative roles of fire and climate in determining canopy species composition and aboveground carbon stocks were investigated. Measurements were made along a transect extending from the dark taiga zone of Central Siberia, where Picea and Abies dominate the canopy, into the Larix zone of Eastern Siberia. We test the hypotheses that the change in canopy species composition is based (1 on climate-driven performance only, (2 on fire only, or (3 on fire-performance interactions. We show that the evergreen conifers Picea obovata and Abies sibirica are the natural late-successional species both in Central and Eastern Siberia, provided there has been no fire for an extended period of time. There are no changes in the climate-driven performance of the observed species. Fire appears to be the main factor explaining the dominance of Larix. Of lesser influence were longitude, hydrology and active-layer thickness.

    Stand-replacing fires decreased from 300 to 50 yr between the Yenisei Ridge and the upper Tunguska. Repeated non-stand-replacing surface fires eliminated the regeneration of Abies and Picea. With every 100 yr since the last fire, the percentage of Larix decreased by 20 %.

    Biomass of stems of single trees did not show signs of age-related decline. Relative diameter increment was 0.41 ± 0.20 % at breast height and stem volume increased linearly over time with a rate of about 0.36 t C ha−1 yr−1 independent of age class and species. Stand volumes reached about 130 t C ha−1 (equivalent to about 520 m3 ha−1. Individual trees of Larix were older than 600 yr. The maximum age and biomass seemed to be limited by fungal rot of heart wood. 60 % of old Larix and Picea and 30 % of Pinus sibirica trees were affected by stem rot. Implications for the future role of fire and of plant diseases

  8. Pacific Northwest Laboratory Alaska (ARCTIC) research program

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, W.C.; Eberhardt, L.E.

    1980-03-01

    The current program continues studies of arctic ecosystems begun in 1959 as part of the Cape Thompson Program. Specific ecosystem aspects include studies of the ecology of arctic and red foxes, small mammel and bird population studies, lichen studies, and radiation ecology studies. (ACR)

  9. International Regulation of Central Arctic Ocean Fisheries

    NARCIS (Netherlands)

    Molenaar, E.J.

    2016-01-01

    Due in particular to the impacts of climate change, the adequacy of the international regulation of Central Arctic Ocean fisheries has come under increasing scrutiny in recent years. As shown in this article, however, international regulation of Central Arctic Ocean fisheries is by no means entirely

  10. Traditional Ecological Knowledge in Arctic EIA's

    DEFF Research Database (Denmark)

    Egede, Parnuna Petrina; Hansen, Anne Merrild

    2016-01-01

    The search for new oil and mineral reserves in the Arctic is increasing. This has called for both local and international concerns and opposition to the activities based on environmental apprehensions. Environmental Impact Assessments (EIA’s) have been implemented in legislations by the Arctic...

  11. Arctic freshwater export: Status, mechanisms, and prospects

    NARCIS (Netherlands)

    Haine, T.W.N.; Curry, B.; Gerdes, R.; Hansen, E.; Karcher, M.; Lee, C.; Rudels, B.; Spreen, G.; de Steur, L.; Stewart, K.D.; Woodgate, R.

    2015-01-01

    Large freshwater anomalies clearly exist in the Arctic Ocean. For example, liquid freshwater has accumulated in the Beaufort Gyre in the decade of the 2000s compared to 1980–2000, with an extra ˜ 5000 km3 — about 25% — being stored. The sources of freshwater to the Arctic from precipitation and runo

  12. Linking Arctic amplification and local feedbacks

    Science.gov (United States)

    Balcerak, Ernie

    2011-11-01

    Climate simulations show that as the Earth warms, the Arctic warms more than the average global warming. However, models differ on how much more the Arctic warms, and although scientists have proposed a variety of mechanisms to explain the Arctic warming amplification, there is no consensus on the main reasons for it. To shed light on this issue, Hwang et al. investigated the relationship between Arctic amplification and poleward energy transport and local Arctic feedbacks, such as changes in cloud cover or ice loss, across a group of models. The researchers noted that differences in atmospheric energy transport did not explain the ranges of polar amplification; rather, models with more amplification showed less energy transport into high latitudes. The authors found that decreasing energy transport is due to a coupled relationship between Arctic amplification and energy transport: Arctic amplification reduces the equator-to-pole temperature gradient, which strongly decreases energy transport. They suggest that this coupled relationship should be taken into account in studies of Arctic amplification. (Geophysical Research Letters, doi:10.1029/2011GL048546, 2011)

  13. Health in the Arctic and climate change

    OpenAIRE

    Sloth Pedersen, Henning

    2007-01-01

    The Arctic environment is like a magnifying glass. Many of the hazards stemming from industrial activity in the South tend to concentrate in the North. This is true for DDT, PCB, heavy metals and many other substances that may endanger human health. Climate change is yet another example of how the negative impact of industrial activity may be magnified in the Arctic region.

  14. Modeling methane emissions from arctic lakes: Model development and site-level study

    Science.gov (United States)

    Tan, Zeli; Zhuang, Qianlai; Walter Anthony, Katey

    2015-06-01

    To date, methane emissions from lakes in the pan-arctic region are poorly quantified. In order to investigate the response of methane emissions from this region to global warming, a process-based climate-sensitive lake biogeochemical model was developed. The processes of methane production, oxidation, and transport were modeled within a one-dimensional sediment and water column. The sizes of 14C-enriched and 14C-depleted carbon pools were explicitly parameterized. The model was validated using observational data from five lakes located in Siberia and Alaska, representing a large variety of environmental conditions in the arctic. The model simulations agreed well with the measured water temperature and dissolved CH4 concentration (mean error less than 1°C and 0.2 μM, respectively). The modeled CH4 fluxes were consistent with observations in these lakes. We found that bubbling-rate-controlling nitrogen (N2) stripping was the most important factor in determining CH4 fraction in bubbles. Lake depth and ice cover thickness in shallow waters were also controlling factors. This study demonstrated that the thawing of Pleistocene-aged organic-rich yedoma can fuel sediment methanogenesis by supplying a large quantity of labile organic carbon. Observations and modeling results both confirmed that methane emission rate at thermokarst margins of yedoma lakes was much larger (up to 538 mg CH4 m-2 d-1) than that at nonthermokarst zones in the same lakes and a nonyedoma, nonthermokarst lake (less than 42 mg CH4 m-2 d-1). The seasonal variability of methane emissions can be explained primarily by energy input and organic carbon availability.

  15. Climate change and Arctic ecosystems: 2. Modeling, paleodata-model comparisons, and future projections

    Science.gov (United States)

    Kaplan, J.O.; Bigelow, N.H.; Prentice, I.C.; Harrison, S.P.; Bartlein, P.J.; Christensen, T.R.; Cramer, W.; Matveyeva, N.V.; McGuire, A.D.; Murray, D.F.; Razzhivin, V.Y.; Smith, B.; Walker, D. A.; Anderson, P.M.; Andreev, A.A.; Brubaker, L.B.; Edwards, M.E.; Lozhkin, A.V.

    2003-01-01

    Large variations in the composition, structure, and function of Arctic ecosystems are determined by climatic gradients, especially of growing-season warmth, soil moisture, and snow cover. A unified circumpolar classification recognizing five types of tundra was developed. The geographic distributions of vegetation types north of 55??N, including the position of the forest limit and the distributions of the tundra types, could be predicted from climatology using a small set of plant functional types embedded in the biogeochemistry-biogeography model BIOME4. Several palaeoclimate simulations for the last glacial maximum (LGM) and mid-Holocene were used to explore the possibility of simulating past vegetation patterns, which are independently known based on pollen data. The broad outlines of observed changes in vegetation were captured. LGM simulations showed the major reduction of forest, the great extension of graminoid and forb tundra, and the restriction of low- and high-shrub tundra (although not all models produced sufficiently dry conditions to mimic the full observed change). Mid-Holocene simulations reproduced the contrast between northward forest extension in western and central Siberia and stability of the forest limit in Beringia. Projection of the effect of a continued exponential increase in atmospheric CO2 concentration, based on a transient ocean-atmosphere simulation including sulfate aerosol effects, suggests a potential for larger changes in Arctic ecosystems during the 21st century than have occurred between mid-Holocene and present. Simulated physiological effects of the CO2 increase (to > 700 ppm) at high latitudes were slight compared with the effects of the change in climate.

  16. CHARACTERISTICS OF HYDROCARBON EXPLOITATION IN ARCTIC CIRCLE

    Directory of Open Access Journals (Sweden)

    Vanja Lež

    2013-12-01

    Full Text Available The existence of large quantities of hydrocarbons is supposed within the Arctic Circle. Assumed quantities are 25% of the total undiscovered hydrocarbon reserves on Earth, mostly natural gas. Over 500 major and minor gas accumulations within the Arctic Circle were discovered so far, but apart from Snøhvit gas field, there is no commercial exploitation of natural gas from these fields. Arctic gas projects are complicated, technically hard to accomplish, and pose a great threat to the return of investment, safety of people and equipment and for the ecosystem. Russia is a country that is closest to the realization of the Arctic gas projects that are based on the giant gas fields. The most extreme weather conditions in the seas around Greenland are the reason why this Arctic region is the least explored and furthest from the realization of any gas project (the paper is published in Croatian .

  17. Arctic ecosystem responses to a warming climate

    DEFF Research Database (Denmark)

    Mortensen, Lars O.

    The Arctic embraces one of the simplest terrestrial ecosystems in the world and yet it covers roughly 11% of the world’s surface. Summer temperatures rarely exceed 10°C and most of the limited precipitation falls as snow. The landmasses are predominantly polar tundra, while the Arctic Ocean...... is frozen solid for the main part of the year. However, in recent decades, arctic temperatures have in-creased between two and three times that of the global averages, which have had a substantial impact on the physical environment of the arctic ecosystem, such as deglaciation of the Greenland inland ice...... sheet, loss of multiannual sea-ice and significant advances in snowmelt days. The biotic components of the arctic ecosystem have also been affected by the rapid changes in climate, for instance resulting in the collapse of the collared lemming cycle, advances in spring flowering and changes in the intra...

  18. Marine Arctic science capability making big strides

    Science.gov (United States)

    Johnson, Leonard; Brass, Garrett

    The profound influence of the Arctic Ocean on global environment, the rapid variability of Arctic processes, and the unresolved geology of the ocean floor have led to growing scientific interest in this region. Ongoing studies are investigating recent historical processes and modern processes such as changes in ocean circulation and ice cover patterns. Sediments beneath the Arctic Ocean record long- and short-term waxing and waning of the cryosphere in the Northern Hemisphere and its linkages to bottom water renewal and faunal adaptation. Underlying basement rocks reflect the tectonic history of the ocean basin, including its ridges and plateaus, which are unsampled and of unknown composition and origin. The vulnerability of Arctic populations to environmental problems makes the need to understand the region even more compelling (see, for example, Arctic Monitoring and Assessment Programme, 1997; also see Web site http://www.grida.no/amap).

  19. Establishing Shared Knowledge about Globalization in Asia and the Arctic

    DEFF Research Database (Denmark)

    Bertelsen, Rasmus Gjedssø; Graczyk, Piotr

    2016-01-01

    We discuss the role of knowledge in relations between Arctic communities and Asia (the Arctic Council observer states: China, India, Japan, Singapore, South Korea). We argue that mutual and shared knowledge between Arctic communities and Asia is necessary for local benefits and comprehensively...... sustainable development for Arctic communities under globalization....

  20. Marine Transportation Implications of the Last Arctic Sea Ice Refuge

    Science.gov (United States)

    Brigham, L. W.

    2010-12-01

    Marine access is increasing throughout the Arctic Ocean and the 'Last Arctic Sea Ice Refuge' may have implications for governance and marine use in the region. Arctic marine transportation is increasing due to natural resource developemnt, increasing Arctic marine tourism, expanded Arctic marine research, and a general linkage of the Arctic to the gloabl economy. The Arctic Council recognized these changes with the release of the Arctic Marine Shipping Assessment of 2009. This key study (AMSA)can be viewed as a baseline assessment (using the 2004 AMSA database), a strategic guide for a host of stakeholders and actors, and as a policy document of the Arctic Council. The outcomes of AMSA of direct relevance to the Ice Refuge are within AMSA's 17 recommendations provided under three themes: Enhancing Arctic Marine Safety, Protecting Arctic People and the Environment, and Building the Arctic Marine Infrastructure. Selected recommendations of importance to the Ice Refuge include: a mandatory polar navigation code; identifying areas of heightened ecological and cultural significance; potential designation of special Arctic marine areas; enhancing the tracking and monitoring of Arctic marine traffic; improving circumpolar environmental response capacity; developing an Arctic search and rescue agreement; and, assessing the effects of marine transportation on marine mammals. A review will be made of the AMSA outcomes and how they can influence the governance, marine use, and future protection of this unique Arctic marine environment.

  1. The response of Arctic vegetation to the summer climate: relation between shrub cover, NDVI, surface albedo and temperature

    International Nuclear Information System (INIS)

    Recently observed Arctic greening trends from normalized difference vegetation index (NDVI) data suggest that shrub growth is increasing in response to increasing summer temperature. An increase in shrub cover is expected to decrease summer albedo and thus positively feed back to climate warming. However, it is unknown how albedo and NDVI are affected by shrub cover and inter-annual variations in the summer climate. Here, we examine the relationship between deciduous shrub fractional cover, NDVI and albedo using field data collected at a tundra site in NE Siberia. Field data showed that NDVI increased and albedo decreased with increasing deciduous shrub cover. We then selected four Arctic tundra study areas and compiled annual growing season maximum NDVI and minimum albedo maps from MODIS satellite data (2000-10) and related these satellite products to tundra vegetation types (shrub, graminoid, barren and wetland tundra) and regional summer temperature. We observed that maximum NDVI was greatest in shrub tundra and that inter-annual variation was negatively related to summer minimum albedo but showed no consistent relationship with summer temperature. Shrub tundra showed higher albedo than wetland and barren tundra in all four study areas. These results suggest that a northwards shift of shrub tundra might not lead to a decrease in summer minimum albedo during the snow-free season when replacing wetland tundra. A fully integrative study is however needed to link results from satellite data with in situ observations across the Arctic to test the effect of increasing shrub cover on summer albedo in different tundra vegetation types.

  2. The USSR/Russia, Norway and international co-operation on environmental matters in the Arctic, 1984-1996

    OpenAIRE

    Karelina, Irina

    2013-01-01

    This thesis examines the USSR, Norway and international cooperation on environmental matters in the Arctic (1984-1996). During the Cold War, the region attracted much attention from of the main adversaries. It was a playground for strategic planners and a laboratory for the improvement of military technology. But at the same time these territories were also – at least potentially – a source for contacts between scientist of the East and the West. Especially in the last decade of the Cold War,...

  3. Dinosaur evolution. A Jurassic ornithischian dinosaur from Siberia with both feathers and scales.

    Science.gov (United States)

    Godefroit, Pascal; Sinitsa, Sofia M; Dhouailly, Danielle; Bolotsky, Yuri L; Sizov, Alexander V; McNamara, Maria E; Benton, Michael J; Spagna, Paul

    2014-07-25

    Middle Jurassic to Early Cretaceous deposits from northeastern China have yielded varied theropod dinosaurs bearing feathers. Filamentous integumentary structures have also been described in ornithischian dinosaurs, but whether these filaments can be regarded as part of the evolutionary lineage toward feathers remains controversial. Here we describe a new basal neornithischian dinosaur from the Jurassic of Siberia with small scales around the distal hindlimb, larger imbricated scales around the tail, monofilaments around the head and the thorax, and more complex featherlike structures around the humerus, the femur, and the tibia. The discovery of these branched integumentary structures outside theropods suggests that featherlike structures coexisted with scales and were potentially widespread among the entire dinosaur clade; feathers may thus have been present in the earliest dinosaurs.

  4. Yuri Vella on the Move: Driving an uazik in Western Siberia

    Directory of Open Access Journals (Sweden)

    Liivo Niglas

    2011-12-01

    Full Text Available In this paper, I want to demonstrate how modern technology can beemployed in the sustainability strategy of an indigenous person who is trying to hold on to a traditional mode of existence. In the case of Yuri Vella, who is the main research subject of this study, modern technology is not only used for carrying out everyday domestic and economic activities. For him it is also a tool to withstand corporate pressure on traditional sources of livelihood. Yuri Vella has incorporated a wide range of modern technological devices into his forest universe. I will argue that one of the most crucial technological items he is relying on in his daily struggle for economic, cultural and political survival is a car. Paradoxically, the extraction of oil that is needed to sustain his “automobility”,is a principal factor that is threatening his indigenous way of life in this oil-rich region of Western Siberia.

  5. Deep water paleo-iceberg scouring on top of Hovgaard Ridge-Arctic Ocean

    Science.gov (United States)

    Arndt, Jan Erik; Niessen, Frank; Jokat, Wilfried; Dorschel, Boris

    2014-07-01

    In multibeam echosounder and subbottom profiler data acquired during R/V Polarstern cruise ARK-VII/3a from the Hovgaard Ridge (Fram Strait), we found evidence for very deep (>1200 m) iceberg scouring. Five elongated seafloor features have been detected that are interpreted to be iceberg scours. The scours are oriented in north-south/south-north direction and are about 15 m deep, 300 m wide, and 4 km long crossing the entire width of the ridge. They are attributed to multiple giant paleo-icebergs that most probably left the Arctic Ocean southward through Fram Strait. The huge keel depths are indicative of ice sheets extending into the Arctic Ocean being at least 1200 m thick at the calving front during glacial maxima. The deep St. Anna Trough or grounded ice observed at the East Siberian Continental Margin are likely source regions of these icebergs that delivered freshwater to the Nordic Seas.

  6. Freshwater Variability in the Arctic Ocean and Subpolar North Atlantic: a Comparison from the 1990s to Present

    Science.gov (United States)

    Horn, Myriel; Rabe, Benjamin; Schauer, Ursula

    2016-04-01

    A significant increase in liquid freshwater content has been observed in the Arctic Ocean over the last 20 years, whereas the Arctic sea ice volume shrank significantly. In contrast, the North Atlantic became more saline in recent years. Both regions are of great importance for the global ocean circulation and climate, and salinity changes may have a profound impact on the global climate. We found that for the period between 1992 and 2013, the liquid freshwater content of the subpolar North Atlantic, calculated from objectively mapped in-situ salinity measurements, and the total freshwater content of the Arctic Ocean, i.e. the liquid freshwater content and freshwater stored in sea ice, are significantly negative correlated (r=-0.77). Moreover, the amount of the anomalies are of the same size. Furthermore, the time series hint at multi-decadal oscillations. The highest negative correlation with the total freshwater content of the Arctic Ocean can be found in the Irminger and Labrador Seas, while we observed a positive correlation east of the Mid-Atlantic Ridge at the path of the North Atlantic Current, which is the source of Atlantic Water entering the Arctic Ocean through the Nordic Seas. We suggest a redistribution of freshwater as a response to frequent changes in atmospheric pressure patterns. Under certain conditions the freshwater is re-routed and kept in the Arctic Ocean, while it is released under other conditions. We conclude that decadal scale changes of the freshwater content in the North Atlantic, particularly those in the deep water formation sites like the Labrador Sea, are originating in the Arctic Ocean.

  7. Methane emissions proportional to permafrost carbon thawed in Arctic lakes since the 1950s

    Science.gov (United States)

    Walter Anthony, Katey; Daanen, Ronald; Anthony, Peter; Schneider von Deimling, Thomas; Ping, Chien-Lu; Chanton, Jeffrey P.; Grosse, Guido

    2016-09-01

    Permafrost thaw exposes previously frozen soil organic matter to microbial decomposition. This process generates methane and carbon dioxide, and thereby fuels a positive feedback process that leads to further warming and thaw. Despite widespread permafrost degradation during the past ~40 years, the degree to which permafrost thaw may be contributing to a feedback between warming and thaw in recent decades is not well understood. Radiocarbon evidence of modern emissions of ancient permafrost carbon is also sparse. Here we combine radiocarbon dating of lake bubble trace-gas methane (113 measurements) and soil organic carbon (289 measurements) for lakes in Alaska, Canada, Sweden and Siberia with numerical modelling of thaw and remote sensing of thermokarst shore expansion. Methane emissions from thermokarst areas of lakes that have expanded over the past 60 years were directly proportional to the mass of soil carbon inputs to the lakes from the erosion of thawing permafrost. Radiocarbon dating indicates that methane age from lakes is nearly identical to the age of permafrost soil carbon thawing around them. Based on this evidence of landscape-scale permafrost carbon feedback, we estimate that 0.2 to 2.5 Pg permafrost carbon was released as methane and carbon dioxide in thermokarst expansion zones of pan-Arctic lakes during the past 60 years.

  8. Thermal analysis of wood of the main tree species of Central Siberia

    Directory of Open Access Journals (Sweden)

    S. R. Loskutov

    2015-12-01

    Full Text Available Thermal decomposition of wood from coniferous and deciduous species of Siberia has been studied using thermogravimetry (TG and differential scanning calorimetry (DSC. The tree species were larch Larix sibirica Ledeb., Scots pine Pinus sylvestris L., spruce Picea obovata Ledeb., fir Abies sibirica Ledeb., Siberian pine Pinus sibirica Du Tour., birch Betula pendula Roth., and aspen Populus tremula L. Thermal analysis of wood samples was carried out under oxidative (air and inert (argon atmospheres from 25 to 700 °С at heating rates 10, 20, 40 °С • min–1 (TG/DTG and from 25 to 590 °С at heating rates 10, 40 °С • min–1 (DSC. The stages of thermal decomposition, the temperature intervals, the mass loss, the mass loss rate, the temperature of DTG/DSC peaks, and heating effects were determined for each tree species. The kinetic thermal degradation parameters of wood were obtained by the Broido and Ozawa–Flynn–Wall models. The wood of coniferous and deciduous species of Siberia was characterized on the base of analysis of activation energy values at various stages of thermal decomposition and the relations of activation energy on conversion level of wood substance of different tree species, and also the comparison of mass loss at the same stages of thermal destruction, heating effects, residual mass and other parameters of TG/DTG, DSC. In our opinion, the results of this work present interest for researchers and specialists in the field of forest pyrology, wood science, dendrochemistry.

  9. Carbon balance assessment of a natural steppe of southern Siberia by multiple constraint approach

    Directory of Open Access Journals (Sweden)

    L. Belelli Marchesini

    2007-01-01

    Full Text Available Steppe ecosystems represent an interesting case in which the assessment of carbon balance may be performed through a cross validation of the eddy covariance measurements against ecological inventory estimates of carbon exchanges (Ehman, 2002; Curtis, 2002.

    Indeed, the widespread presence of ideal conditions for the applicability of the eddy covariance technique, as vast and homogeneous grass vegetation cover over flat terrains (Baldocchi, 2003, make steppes a suitable ground to ensure a constrain to flux estimates with independent methodological approaches.

    We report about the analysis of the carbon cycle of a true steppe ecosystem in southern Siberia during the growing season of 2004 in the framework of the TCOS-Siberia project activities performed by continuous monitoring of CO2 fluxes at ecosystem scale by the eddy covariance method, fortnightly samplings of phytomass, and ingrowth cores extractions for NPP assessment, and weekly measurements of heterotrophic component of soil CO2 effluxes obtained by an experiment of root exclusion.

    The carbon balance of the monitored natural steppe was, according to micrometeorological measurements, a sink of carbon of 151.7± 30.1 gC m−2, cumulated during the growing season from May to September. This result was in agreement with the independent estimate through ecological inventory which yielded a sink of 150.1 gC m−2 although this method was characterized by a large uncertainty (±130% considering the 95% confidence interval of the estimate. Uncertainties in belowground process estimates account for a large part of the error. Thus, in particular efforts to better quantify the dynamics of root biomass (growth and turnover have to be undertaken in order to reduce the uncertainties in the assessment of NPP. This assessment should be preferably based on the application of multiple methods, each one characterized by its own merits and

  10. Climate-induced landsliding within the larch dominant permafrost zone of central Siberia

    International Nuclear Information System (INIS)

    Climate impact on landslide occurrence and spatial patterns were analyzed within the larch-dominant communities associated with continuous permafrost areas of central Siberia. We used high resolution satellite imagery (i.e. QuickBird, WorldView) to identify landslide scars over an area of 62 000 km2. Landslide occurrence was analyzed with respect to climate variables (air temperature, precipitation, drought index SPEI), and Gravity Recovery and Climate Experiment satellite derived equivalent of water thickness anomalies (EWTA). Landslides were found only on southward facing slopes, and the occurrence of landslides increased exponentially with increasing slope steepness. Lengths of landslides correlated positively with slope steepness. The observed upper elevation limit of landslides tended to coincide with the tree line. Observations revealed landslides occurrence was also found to be strongly correlated with August precipitation (r = 0.81) and drought index (r = 0.7), with June–July–August soil water anomalies (i.e., EWTA, r = 0.68–0.7), and number of thawing days (i.e., a number of days with t max > 0°C; r = 0.67). A significant increase in the variance of soil water anomalies was observed, indicating that occurrence of landslides may increase even with a stable mean precipitation level. The key-findings of this study are (1) landslides occurrence increased within the permafrost zone of central Siberia in the beginning of the 21st century; (2) the main cause of increased landslides occurrence are extremes in precipitation and soil water anomalies; and (3) landslides occurrence are strongly dependent on relief features such as southward facing steep slopes. (letter)

  11. Obesity in occupational groups of Western Siberia: comparison with representative national data

    Directory of Open Access Journals (Sweden)

    S A Maksimov

    2013-03-01

    Full Text Available The aim of this study was to compare obesity prevalences in the occupational groups of Western Siberia with the national data. Materials and methods: We performed a single-step cross-sectional study enrolling 4472 employees of 14 occupational groups from Western Siberian institutions and enterprises. Obesity was considered to be present if the body mass index was >30.0 kg/m2; sex, age and education data were obtained with questionnaires. Age-adjusted obesity prevalence in the occupational groups (separately for men and women was compared with the national data with calculation of odds ratio, attributable risk and 95% confidence interval. Results: Among women the prevalence of obesity was lower in teachers compared with the national data (OR=0.45; 95% CI: 0.31–0.66. Higher obesity prevalence was observed among operating personnel and technical workers (OR=1.69; 95% CI: 1.37–2.09 as well as metallurgy equipment operators (OR=1.65; 95% CI: 1.17–2.31. Among males higher obesity prevalence was registered in top-managers (OR=2.53; 95% CI: 1.80–3.55, operating personnel and technical workers (OR=2.03; 95% CI: 1.59–2.58, civil servants (OR=1.75; 95% CI: 1.27–2.40, and mechanics (OR=1.37; 95% CI: 1.08–1.73. Moreover, in women university education (higher percentage of employees having graduated from a higher professional institution led to less obesity prevalence. In males no such tendencies were observed. Conclusions: The study allowed to identify the occupational groups of Western Siberia with higher obesity prevalence and to demonstrate the impact of sex and education level on this parameter. The obtained data can make a theoretical and practical basis for primary and secondary prevention of obesity in the workplace.

  12. Climate-induced landsliding within the larch dominant permafrost zone of central Siberia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Shushpanov, Alexandr S.; Im, Sergei T.; Ranson, Kenneth J.

    2016-04-01

    Climate impact on landslide occurrence and spatial patterns were analyzed within the larch-dominant communities associated with continuous permafrost areas of central Siberia. We used high resolution satellite imagery (i.e. QuickBird, WorldView) to identify landslide scars over an area of 62 000 km2. Landslide occurrence was analyzed with respect to climate variables (air temperature, precipitation, drought index SPEI), and Gravity Recovery and Climate Experiment satellite derived equivalent of water thickness anomalies (EWTA). Landslides were found only on southward facing slopes, and the occurrence of landslides increased exponentially with increasing slope steepness. Lengths of landslides correlated positively with slope steepness. The observed upper elevation limit of landslides tended to coincide with the tree line. Observations revealed landslides occurrence was also found to be strongly correlated with August precipitation (r = 0.81) and drought index (r = 0.7), with June-July-August soil water anomalies (i.e., EWTA, r = 0.68-0.7), and number of thawing days (i.e., a number of days with t max > 0 °C r = 0.67). A significant increase in the variance of soil water anomalies was observed, indicating that occurrence of landslides may increase even with a stable mean precipitation level. The key-findings of this study are (1) landslides occurrence increased within the permafrost zone of central Siberia in the beginning of the 21st century; (2) the main cause of increased landslides occurrence are extremes in precipitation and soil water anomalies; and (3) landslides occurrence are strongly dependent on relief features such as southward facing steep slopes.

  13. IEA studies Middle East

    International Nuclear Information System (INIS)

    Oil production policy in most of the major producing countries of the Middle East looks likely to change as a result of financial constraints and pressures on demand. This -implicitly rather than explicitly - is perhaps the main conclusion to be drawn from the International Energy Agency's (IEA) magisterial study on Middle East oil and gas, in which the production capacities, energy development policies and the structural economic problems of six major oil and gas producers in the region are examined. ''Middle East Oil and Gas'' is available from the IEA/OECD Publications Service. (author)

  14. Sources and fate of freshwater exported in the East Greenland Current

    Science.gov (United States)

    Dodd, Paul A.; Heywood, Karen J.; Meredith, Michael P.; Naveira-Garabato, Alberto C.; Marca, Alina D.; Falkner, Kelly K.

    2009-10-01

    Monitoring the sources and fate of freshwater in the East Greenland Current (EGC) is important, as this water has the potential to suppress deep convection in the Nordic and Labrador Seas if the outflow of freshwater from the Arctic Ocean increases in response to climate change. Here, hydrographic, oxygen isotope ratio and dissolved barium concentration sections across Denmark Strait collected in 1998 and 1999 are used to determine the freshwater composition of the EGC at these times. Comparison of meltwater fluxes at Denmark Strait and Fram Strait indicates a net melting of sea ice into the EGC between these two locations, with a significant proportion of sea ice drifting into the Nordic Seas or on to the East Greenland Shelf. We conclude that the phase of freshwater exiting the Arctic Ocean through Fram Strait is important in determining its possible impact on deep water formation in the Nordic and Labrador Seas.

  15. Arctic Visiting Speakers Series (AVS)

    Science.gov (United States)

    Fox, S. E.; Griswold, J.

    2011-12-01

    The Arctic Visiting Speakers (AVS) Series funds researchers and other arctic experts to travel and share their knowledge in communities where they might not otherwise connect. Speakers cover a wide range of arctic research topics and can address a variety of audiences including K-12 students, graduate and undergraduate students, and the general public. Host applications are accepted on an on-going basis, depending on funding availability. Applications need to be submitted at least 1 month prior to the expected tour dates. Interested hosts can choose speakers from an online Speakers Bureau or invite a speaker of their choice. Preference is given to individuals and organizations to host speakers that reach a broad audience and the general public. AVS tours are encouraged to span several days, allowing ample time for interactions with faculty, students, local media, and community members. Applications for both domestic and international visits will be considered. Applications for international visits should involve participation of more than one host organization and must include either a US-based speaker or a US-based organization. This is a small but important program that educates the public about Arctic issues. There have been 27 tours since 2007 that have impacted communities across the globe including: Gatineau, Quebec Canada; St. Petersburg, Russia; Piscataway, New Jersey; Cordova, Alaska; Nuuk, Greenland; Elizabethtown, Pennsylvania; Oslo, Norway; Inari, Finland; Borgarnes, Iceland; San Francisco, California and Wolcott, Vermont to name a few. Tours have included lectures to K-12 schools, college and university students, tribal organizations, Boy Scout troops, science center and museum patrons, and the general public. There are approximately 300 attendees enjoying each AVS tour, roughly 4100 people have been reached since 2007. The expectations for each tour are extremely manageable. Hosts must submit a schedule of events and a tour summary to be posted online

  16. Seasonality and long term trends in dissolved carbon export from large rivers to the Arctic Ocean, and potential effects on coastal ocean acidification (Invited)

    Science.gov (United States)

    Tank, S. E.; Kokelj, S. V.; Raymond, P. A.; Striegl, R. G.; McClelland, J. W.; Holmes, R. M.; Spencer, R. G.

    2013-12-01

    Large Arctic rivers show marked seasonality in constituent flux as a result of variations in flowpath throughout the yearly cycle. Here, we use measurements collected from the mouths of the six largest rivers draining to the Arctic Ocean to explore seasonal variation in dissolved inorganic and dissolved organic carbon (DIC, DOC) flux, and the effect of this flux on nearshore ocean processes. This work uses data from the Yukon and Mackenzie Rivers in North America, and the Kolyma, Lena, Yenisey, and Ob' in Siberia. Mean monthly concentrations of riverine DIC vary synchronously across all rivers, peaking under ice and reaching a low point immediately after the spring freshet. Monthly climatologies for DIC, in addition to similarly constructed climatologies for Ca2+, show that the input of riverwater universally causes aragonite to be undersaturated in riverine-influenced nearshore regions, with an effect that is greater for the Siberian coast than for western North America, and greater in the spring-winter than in the late summer and fall. Because seasonal trends and geographic variation in DOC concentration are opposite to that for DIC in these large rivers, degradation of DOC to CO2 in the nearshore Arctic should accentuate seasonal and spatial patterns in aragonite undersaturation in Arctic coastal regions. Datasets that extend DIC and DOC concentration measurements back to the early 1970's (DIC) and early 1980's (DOC) near the mouth of the Mackenzie River in the western Canadian Arctic indicate that the summertime concentration and flux of these constituents has been increasing over time in this region. While evidence from other regions of the pan-Arctic, and data gathered from smaller sub-catchment studies indicate that this trend is not universal for DOC, there is growing evidence for a consistent increase in summertime DIC flux across both time and gradients of decreasing permafrost extent. These changes, in turn, could have broad implications for both

  17. THE ARCTIC: AN INDICATOR OF THE PLANET"S HEALTH

    OpenAIRE

    Callaghan, Terry

    2012-01-01

    The Arctic is a critically important component of the earth system and the Arctic is subject to dramatic change due to global warming in particular. To build capacity for better environmental monitoring and research in the Arctic, the EU has funded the SCANNET-INTERACT Consortium, which consists of partners from all the Arctic countries and 33 research infrastructures located throughout the large environmental envelope of the Arctic and a further 8 research facilities have joined as "observer...

  18. East African odontopygid millipedes

    DEFF Research Database (Denmark)

    Frederiksen, Sara B.

    2013-01-01

    Two new genera and three new species in the millipede family Odontopygidae are described; Lamelloramus rhombiformis, L. triangularis and Aquattuor denticulatus. All three species are found in the East Usambara Mountains. Copyright © 2013 Magnolia Press....

  19. Fluxus East / Petra Stegmann

    Index Scriptorium Estoniae

    Stegmann, Petra

    2008-01-01

    Näitusest "Fluxus East" Kumu Kunstimuuseumis. Fluxuse liikumisest leedu kunstniku George Maciunase (1931-1978) eestvedamisel. Liikumise ilmingutest Eestis (happeningid, muusikaaktsioonid, visuaalne poeesia, mail art). Kuraator Petra Stegmann, kujundaja Andrea Pichl

  20. About some processes of replacement of PGM from the placers of Southern Siberia

    Science.gov (United States)

    Shvedov, G. I.; Knyazev, V. N.; Nekos, V. V.

    2003-04-01

    -standard gold on the boundary of cuperite and Pt-Fe alloy. Same edgings of gold round the grains of alloys with consequent overlap by a more broad band of cuperite were observed by S.A. Shcheka with the co-authors in PGM from placers of Far East /4/. According to these authors the forming of edgings of gold is connected to effect of gold-bearing solutions with low fugitivity of S and As on the Pt-Fe alloy. Hereinafter under the opinion of the quoted authors the concentrations of S and As have increased and cuperite or arsenides (sulfoarsenides) of platinum were formed. On ours opinion the forming of edgings of gold between PtS and Pt-Fe alloy may occur by two ways. At the first, the allocation of the bands of high-standard gold on the boundary Pt-Fe alloy and PtS was simultaneously with replacement. It is connected that the gold and silver was included in the crystalline of Pt-Fe alloys primary and at the time of replacement of this mineral these elements reduced to native phase because the entry to the lattice of cuperite is impossible. Such process can be presented as the following equation: (Pt,Pd,Au,Ag)_3Fe + 2S_2 =3(Pt,Pd)S + 3(Au,Ag)^0 + FeS There aren't crystallochemical prohibitions for such process. At the second, the gold from later solutions may penetrate deep into the grain through porous edging of cuperite and locate at the boundary of PtS and Pt-Fe alloy. Probability of these processes must be test by experiments. The cuperite edgings on Pt-Fe alloys are acquired by the band or metacrystalls of sperrilite later. It is connected to occurrence of arsenic in the system. A feature of the composition of these sperrylites is increased contents of those elements, which originally were included in the lattice of Pt-Fe alloys (Rh, Ir, Os). The complex replacements of Pt-Fe alloys were observed by the authors in placer Sysim river. Pt-Fe alloys from this placer are presented by small-sized isomeric grains and contain increased contents of rhodium (tab., No.7). This feature

  1. East Asia's Security System

    OpenAIRE

    Hojzáková, Věra

    2012-01-01

    The aim of the master thesis is to characterize and evaluate the current security system in East Asia, to show the security strategies of the system actors and the existing friction points, and to assess the future development of the security system in place. For this purpose the author first defines the East Asia's security system using the conceptual tools of three international relations theories, namely neo-realism, neo-liberalism, and constructivism. In the following section, the securit...

  2. Leukaemia in East Suffolk

    International Nuclear Information System (INIS)

    An investigation was conducted by the East Suffolk Health Authority to determine whether there were any geographical variations in the incidence of leukaemia over the last fifteen years in East Suffolk suggesting an environmental hazard, e.g. Sizewell Power Station. No areas were found to have a statistically significant increased incidence of leukaemia cases although there did appear to be a cluster of cases in the Leiston area. (U.K.)

  3. Arctic Energy Resources: Security and Environmental Implications

    Directory of Open Access Journals (Sweden)

    Peter Johnston

    2012-08-01

    Full Text Available n recent years, there has been considerable interest in the Arctic as a source for resources, as a potential zone for commercial shipping, and as a region that might experience conflict due to its strategic importance. With regards to energy resources, some studies suggest that the region contains upwards of 13 percent of global undiscovered oil, 30 percent of undiscovered gas, and multiples more of gas hydrates. The decreasing amount and duration of Arctic ice cover suggests that extraction of these resources will be increasingly commercially viable. Arctic and non-arctic states wish to benefit from the region's resources and the potential circum-polar navigation possibilities. This has led to concerns about the environmental risks of these operations as well as the fear that competition between states for resources might result in conflict. Unresolved offshore boundaries between the Arctic states exacerbate these fears. Yet, the risk of conflict seems overstated considering the bilateral and multilateral steps undertaken by the Arctic states to resolve contentious issues. This article will examine the potential impact of Arctic energy resources on global security as well as the regional environment and examine the actions of concerned states to promote their interests in the region.

  4. Does temporal variation of mercury levels in Arctic seabirds reflect changes in global environmental contamination, or a modification of Arctic marine food web functioning?

    Science.gov (United States)

    Fort, Jérôme; Grémillet, David; Traisnel, Gwendoline; Amélineau, Françoise; Bustamante, Paco

    2016-04-01

    Studying long-term trends of contaminants in Arctic biota is essential to better understand impacts of anthropogenic activities and climate change on the exposure of sensitive species and marine ecosystems. We concurrently measured temporal changes (2006-2014) in mercury (Hg) contamination of little auks (Alle alle; the most abundant Arctic seabird) and in their major zooplankton prey species (Calanoid copepods, Themisto libellula, Gammarus spp.). We found an increasing contamination of the food-chain in East Greenland during summer over the last decade. More specifically, bird contamination (determined by body feather analyses) has increased at a rate of 3.4% per year. Conversely, bird exposure to Hg during winter in the northwest Atlantic (determined by head feather analyses) decreased over the study period (at a rate of 1.5% per year), although winter concentrations remained consistently higher than during summer. By combining mercury levels measured in birds and zooplankton to isotopic analyses, our results demonstrate that inter-annual variations of Hg levels in little auks reflect changes in food-chain contamination, rather than a reorganization of the food web and a modification of seabird trophic ecology. They therefore underline the value of little auks, and Arctic seabirds in general, as bio-indicators of long-term changes in environmental contamination. PMID:26798998

  5. Characteristics of colored dissolved organic matter (CDOM) in the Arctic outflow in the Fram Strait: Assessing the changes and fate of terrigenous CDOM in the Arctic Ocean

    Science.gov (United States)

    Granskog, Mats A.; Stedmon, Colin A.; Dodd, Paul A.; Amon, Rainer M. W.; Pavlov, Alexey K.; de Steur, Laura; Hansen, Edmond

    2012-12-01

    Absorption coefficients of colored dissolved organic matter (CDOM) were measured together with salinity, δ18O, and inorganic nutrients across the Fram Strait. A pronounced CDOM absorption maximum between 30 and 120 m depth was associated with river and sea ice brine enriched water, characteristic of the Arctic mixed layer and upper halocline waters in the East Greenland Current (EGC). The lowest CDOM concentrations were found in the Atlantic inflow. We show that the salinity-CDOM relationship is not suitable for evaluating conservative mixing of CDOM. The strong correlation between meteoric water and CDOM is indicative of the riverine/terrigenous origin of CDOM in the EGC. Based on CDOM absorption in Polar Water and comparison with an Arctic river discharge weighted mean, we estimate that a 49-59% integrated loss of CDOM absorption across 250-600 nm has occurred. A preferential removal of absorption at longer wavelengths reflects the loss of high molecular weight material. In contrast, CDOM fluxes through the Fram Strait using September velocity fields from a high-resolution ocean-sea ice model indicate that the net southward transport of terrigenous CDOM through the Fram Strait equals up to 50% of the total riverine CDOM input; this suggests that the Fram Strait export is a major sink of CDOM. These contrasting results indicate that we have to constrain the (C)DOM budgets for the Arctic Ocean much better and examine uncertainties related to using tracers to assess conservative mixing in polar waters.

  6. Does temporal variation of mercury levels in Arctic seabirds reflect changes in global environmental contamination, or a modification of Arctic marine food web functioning?

    Science.gov (United States)

    Fort, Jérôme; Grémillet, David; Traisnel, Gwendoline; Amélineau, Françoise; Bustamante, Paco

    2016-04-01

    Studying long-term trends of contaminants in Arctic biota is essential to better understand impacts of anthropogenic activities and climate change on the exposure of sensitive species and marine ecosystems. We concurrently measured temporal changes (2006-2014) in mercury (Hg) contamination of little auks (Alle alle; the most abundant Arctic seabird) and in their major zooplankton prey species (Calanoid copepods, Themisto libellula, Gammarus spp.). We found an increasing contamination of the food-chain in East Greenland during summer over the last decade. More specifically, bird contamination (determined by body feather analyses) has increased at a rate of 3.4% per year. Conversely, bird exposure to Hg during winter in the northwest Atlantic (determined by head feather analyses) decreased over the study period (at a rate of 1.5% per year), although winter concentrations remained consistently higher than during summer. By combining mercury levels measured in birds and zooplankton to isotopic analyses, our results demonstrate that inter-annual variations of Hg levels in little auks reflect changes in food-chain contamination, rather than a reorganization of the food web and a modification of seabird trophic ecology. They therefore underline the value of little auks, and Arctic seabirds in general, as bio-indicators of long-term changes in environmental contamination.

  7. Significant melting of ice-wedges and formation of thermocirques on hill-slopes of thermokarst lakes in Central Yakutia (Siberia)

    Science.gov (United States)

    Séjourné, Antoine; Costard, François; Gargani, Julien; Fedorov, Alexander; Skorve, Johnny

    2013-04-01

    On Earth, permafrost containing a high ice volume (referred as ice-rich) are sensible to climate change, they have been regionally degraded (thermokarst) during the early Holocene climatic optimum forming numerous thermokarst lakes in Central Yakutia (eastern Siberia). Recent temperature increases in the Arctic and Subarctic have been significantly greater than global averages. The frequency and magnitude of terrain disturbances associated with thawing permafrost are increasing in these regions and are thought to intensify in the future. Therefore, understand how is the current development of thermokarst is a critical question. Here, we describe the significant melting of ice-wedges on slopes of thermokarst lakes that leads to formation of amphitheatrical hollows referred as thermocirques. The evolution of thermocirques in Central Yakutia has been little studied and analyzing their formation could help to understand the recent thermokarst in relation to climate change in Central Yakutia. We studied the thermocirques at two scales: (i) field surveys of different thermocirques in July 2009-2010 and October 2012 to examine the processes and origin of melting of ice-wedges and; (ii) photo-interpretation of time series of satellite images (KH-9 Hexagon images of 6-9 m/pixel and GeoEye images of 50 cm/pixel) to study the temporal evolution of thermocirques. The melting of ground-ice on the scarp of thermocirque triggers falls and small mud-flows that induce the retreat of the scarp parallel to itself. Based on field studies and on GeoEye image comparison, we show that their rate of retrogressive growth is 1-2 m/year. On the hill-slopes of lakes, the thermokarst could be initiated by different processes that lead to the uncover and then melting of ice-wedges: thermal erosion by the waves of the ice-rich bluff; active-layer detachment (a form of slope failure linked to detachment of the seasonally thawed upper ground); flowing of water on the slope (precipitation) or

  8. Survival strategies in arctic ungulates

    Directory of Open Access Journals (Sweden)

    N. J. C. Tyler

    1990-09-01

    Full Text Available Arctic ungulates usually neither freeze nor starve to death despite the rigours of winter. Physiological adaptations enable them to survive and reproduce despite long periods of intense cold and potential undernutrition. Heat conservation is achieved by excellent insulation combined with nasal heat exchange. Seasonal variation in fasting metabolic rate has been reported in several temperate and sub-arctic species of ungulates and seems to occur in muskoxen. Surprisingly, there is no evidence for this in reindeer. Both reindeer and caribou normally maintain low levels of locomotor activity in winter. Light foot loads are important for reducing energy expenditure while walking over snow. The significance and control of selective cooling of the brain during hard exercise (e.g. escape from predators is discussed. Like other cervids, reindeer and caribou display a pronounced seasonal cycle of appetite and growth which seems to have an intrinsic basis. This has two consequences. First, the animals evidently survive perfectly well despite enduring negative energy balance for long periods. Second, loss of weight in winter is not necessarily evidence of undernutrition. The main role of fat reserves, especially in males, may be to enhance reproductive success. The principal role of fat reserves in winter appears to be to provide a supplement to, rather than a substitute for, poor quality winter forage. Fat also provides an insurance against death during periods of acute starvation.

  9. 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

  10. 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

  11. Introduction: World Routes in the Arctic

    Directory of Open Access Journals (Sweden)

    Art Leete

    2011-12-01

    Full Text Available The Arctic is associated in popular perception with a vast frozen snow covered empty place. Everybody who has been in the Arctic, whether in the Eurasian or North American part, knows that this stereotype is correct. Indeed, the Arctic is a place with lots of space that determines the lifestyle of the people in this area. All human activities – whether livelihood or mastering of the territory– are and always have been connected with substantial movement. Hunting, fishing, trading, the establishment of settlements and keeping them alive, all this needs the movement of goods and human resources.

  12. Identification of land surface temperature and albedo trends in AVHRR Pathfinder data from 1982 to 2005 for northern Siberia

    NARCIS (Netherlands)

    Urban, M.; Forkel, M.; Schmullius, C.; Hese, S.; Hüttich, C.; Herold, M.

    2013-01-01

    The arctic regions are highly vulnerable to climate change. Climate models predict an increase in global mean temperatures for the upcoming century. The arctic environment is subject to significant changes of the land surface. Especially the changes of vegetation pattern and the phenological cycle i

  13. Acoustic Monitoring of the Arctic Ice Cap

    Science.gov (United States)

    Porter, D. L.; Goemmer, S. A.; Chayes, D. N.

    2012-12-01

    Introduction The monitoring of the Arctic Ice Cap is important economically, tactically, and strategically. In the scenario of ice cap retreat, new paths of commerce open, e.g. waterways from Northern Europe to the Far East. Where ship-going commerce is conducted, the U.S. Navy and U.S. Coast Guard have always stood guard and been prepared to assist from acts of nature and of man. It is imperative that in addition to measuring the ice from satellites, e.g. Icesat, that we have an ability to measure the ice extent, its thickness, and roughness. These parameters play an important part in the modeling of the ice and the processes that control its growth or shrinking and its thickness. The proposed system consists of three subsystems. The first subsystem is an acoustic source, the second is an array of geophones and the third is a system to supply energy and transmit the results back to the analysis laboratory. The subsystems are described below. We conclude with a plan on how to tackle this project and the payoff to the ice cap modeler and hence the users, i.e. commerce and defense. System Two historically tested methods to generate a large amplitude multi-frequency sound source include explosives and air guns. A new method developed and tested by the University of Texas, ARL is a combustive Sound Source [Wilson, et al., 1995]. The combustive sound source is a submerged combustion chamber that is filled with the byproducts of the electrolysis of sea water, i.e. Hydrogen and Oxygen, an explosive mixture which is ignited via a spark. Thus, no additional compressors, gases, or explosives need to be transported to the Arctic to generate an acoustic pulse capable of the sediment and the ice. The second subsystem would be geophones capable of listening in the O(10 Hz) range and transmitting that data back to the laboratory. Thus two single arrays of geophones arranged orthogonal to each other with a range of 1000's of kilometers and a combustive sound source where the two

  14. Phenological dynamics of arctic tundra vegetation and its implications on satellite imagery interpretation

    Science.gov (United States)

    Juutinen, Sari; Aurela, Mika; Mikola, Juha; Räsänen, Aleksi; Virtanen, Tarmo

    2016-04-01

    Remote sensing is a key methodology when monitoring the responses of arctic ecosystems to climatic warming. The short growing season and rapid vegetation development, however, set demands to the timing of image acquisition in the arctic. We used multispectral very high spatial resolution satellite images to study the effect of vegetation phenology on the spectral reflectance and image interpretation in the low arctic tundra in coastal Siberia (Tiksi, 71°35'39"N, 128°53'17"E). The study site mainly consists of peatlands, tussock, dwarf shrub, and grass tundra, and stony areas with some lichen and shrub patches. We tested the hypotheses that (1) plant phenology is responsive to the interannual weather variation and (2) the phenological state of vegetation has an impact on satellite image interpretation and the ability to distinguish between the plant communities. We used an empirical transfer function with temperature sums as drivers to reconstruct daily leaf area index (LAI) for the different plant communities for years 2005, and 2010-2014 based on measured LAI development in summer 2014. Satellite images, taken during growing seasons, were acquired for two years having late and early spring, and short and long growing season, respectively. LAI dynamics showed considerable interannual variation due to weather variation, and particularly the relative contribution of graminoid dominated communities was sensitive to these phenology shifts. We have also analyzed the differences in the reflectance values between the two satellite images taking account the LAI dynamics. These results will increase our understanding of the pitfalls that may arise from the timing of image acquisition when interpreting the vegetation structure in a heterogeneous tundra landscape. Very high spatial resolution multispectral images are available at reasonable cost, but not in high temporal resolution, which may lead to compromises when matching ground truth and the imagery. On the other hand

  15. Temperature and moisture effects on ammonia oxidizer communities in cryoturbated Arctic soils

    Science.gov (United States)

    Aiglsdorfer, Stefanie; Alves, Ricardo J. E.; Bárta, Jiří; Kohoutová, Iva; Bošková, Hana; Diáková, Katerina; Čapek, Petr; Schnecker, Jörg; Wild, Birgit; Mooshammer, Maria; Urich, Tim; Gentsch, Norman; Gittel, Antje; Guggenberger, Georg; Mikutta, Robert; Lashchinskiy, Nikolay; Richter, Andreas; Šantrůčková, Hana; Shibistova, Olga; Schleper, Christa

    2014-05-01

    Arctic permafrost-affected soils contain large amounts of soil organic carbon (SOC) and are expected to experience drastic changes in environmental conditions, such as moisture and temperature, due to the high surface temperature increase predicted for these regions. Although the SOC decomposition processes driven by the microbiota are considered to be nitrogen (N) limited, little information about the microbial groups involved in N cycle is currently available, including their reactions to environmental changes. Here, we investigate the presence of ammonia oxidizing archaea (AOA) and bacteria (AOB) in distinct soil horizons from the Taymyr peninsula (Siberia, Russia), and investigate their activities under changing temperature and moisture regimes. These two groups of organisms perform the first step in nitrification, an important and rate limiting process in the global N cycle, which involves the oxidation of ammonia to nitrate via nitrite. The soil samples were separated into different horizons: organic topsoil (O) and subducted organic topsoil (Ajj). The samples were incubated for 18 weeks at 4, 12 and 20° C and 50, 80 and 100 % water holding capacity (WHC). AOA and AOB abundances were quantified by quantitative PCR targeting genes of the key metabolic enzyme, ammonia monooxygenase. AOA diversity was analyzed in-depth by high-throughput amplicon sequencing of the same gene. Additionally, gross and net nitrification and mineralization rates were determined in order to investigate potential relationships between AOA and AOB populations and these processes, in response to the incubation treatments. We found higher abundances of AOA than AOB in the organic topsoil, whereas AOB dominated in the subducted organic topsoil. Increased temperature resulted in higher numbers of both groups at low WHC %, with AOB showing a more pronounced response. However, these effects were not observed under anaerobic conditions (100 % WHC). Deep sequencing of AOA amoA genes revealed

  16. Optical dating of perennially frozen deposits associated with preserved ancient plant and animal DNA in north-central Siberia

    DEFF Research Database (Denmark)

    Arnold, L.J.; Roberts, R.G.; Macphee, R.D.E.;

    2008-01-01

    We present chronological constraints on a suite of permanently frozen fluvial deposits which contain ancient DNA (aDNA) from the Taimyr Peninsula of north-central Siberia. The luminescence phenomenology of these samples is first discussed, focusing on the optically stimulated luminescence (OSL) d...... of providing a reliable chronometric framework for sedimentary aDNA records in permafrost environments. (C) 2007 Elsevier Ltd. All rights reserved Udgivelsesdato: 2008...

  17. Abundance, Distribution and Potential Activity of Methane Oxidising Bacteria in Permafrost Soils from the Lena Delta, Siberia

    OpenAIRE

    Susanne Liebner; Dirk Wagner;  

    2007-01-01

    The methane oxidation potential of active layer profiles of permafrost soils from the Lena Delta, Siberia, was studied with regard to its respond to temperature, and abundance and distribution of type I and type II methanotrophs. Our results indicate vertical shifts within the optimal methane oxidation temperature and within the distribution of type I and type II methanotrophs. In the upper active layer, maximum methane oxidation potentials were detected at 21 °C. Deep active layer zones that...

  18. To what extent could water isotopic measurements help us understand model biases in the water cycle over Western Siberia

    OpenAIRE

    Gryazin, V.; Risi, C.; J. Jouzel; Kurita, N; Worden, J.; Frankenberg, C.; V. Bastrikov; Gribanov, K.; O. Stukova

    2014-01-01

    We evaluate the isotopic composition of water vapor and precipitation simulated by the LMDZ (Laboratoire de Météorologie Dynamique-Zoom) GCM (General Circulation Model) over Siberia using several data sets: TES (Tropospheric Emission Spectrometer) and GOSAT (Greenhouse gases Observing SATellite) satellite observations of tropospheric water vapor, GNIP (Global Network for Isotopes in Precipitation) and SNIP (Siberian Network for Isotopes in Precipitation) precipitation networ...

  19. Effect of permafrost thawing on organic carbon and trace element colloidal speciation in the thermokarst lakes of western Siberia

    OpenAIRE

    O. S. Pokrovsky; Shirokova, L. S.; S. N. Kirpotin; S. Audry; Viers, J.; B. Dupré

    2011-01-01

    To examine the mechanisms of carbon mobilization and biodegradation during permafrost thawing and to establish a link between organic carbon (OC) and other chemical and microbiological parameters in forming thermokarst (thaw) lakes, we studied the biogeochemistry of OC and trace elements (TEs) in a chronosequence of small lakes that are being formed due to permafrost thawing in the northern part of western Siberia. Twenty lakes and small ponds of various sizes and ages were sampled for dissol...

  20. Novel biodiversity baselines outpace models of fish distribution in Arctic waters

    Science.gov (United States)

    Christiansen, Jørgen S.; Bonsdorff, Erik; Byrkjedal, Ingvar; Fevolden, Svein-Erik; Karamushko, Oleg V.; Lynghammar, Arve; Mecklenburg, Catherine W.; Møller, Peter D. R.; Nielsen, Julius; Nordström, Marie C.; Præbel, Kim; Wienerroither, Rupert M.

    2016-02-01

    During a recent marine biological expedition to the Northeast Greenland shelf break (latitudes 74-77 °N), we made the first discovery of Atlantic cod ( Gadus morhua), beaked redfish ( Sebastes mentella) and capelin ( Mallotus villosus). Our novel observations shift the distribution range of Atlantic cod >1000 km further north in East Greenland waters. In light of climate change, we discuss physical forcing and putative connections between the faunas of the Northeast Greenland shelf and the Barents Sea. We emphasise the importance of using real data in spread scenarios for understudied Arctic seas.

  1. Russia and Islam: state policy on formation of tolerance of Muslims in Western Siberia (1773–1917

    Directory of Open Access Journals (Sweden)

    Yulia A. Bortnikova

    2016-03-01

    Full Text Available Counteraction to Islamic extremism is the major problem in the modern world. The government of the Russian Empire solved this problem through purposeful education of confessional tolerance of Muslims in 1773–1917. Authors compare understanding of tolerance in Russia and in Western Siberia in 1773-1917, emphasizing that in the Tyumen region society understood this term the same as now. On the basis of earlier unknown archival documents of the Central historical archive of the Republic of Bashkortostan authors consider a state policy on formation of a certain option of Islam which provides religious tolerance in Russia. In article the main attention is paid to Western Siberia as exactly there the confessional state policy made the greatest success. The main directions of a state policy were: to unify Muslim culture according to orthodox samples; to keep the Siberian option of Islam; to create obstacles for distribution of standard Islam; to develop the state measures which would show respect for Muslims and care of them. Authors consider ways of deformation of Muslim culture in Western Siberia: change of architectural forms of mosques and necropolises, deformation of cult objects (existence of a religious sculpture, selection of literature in Muslim libraries, the facilitated conditions for examinations on the mullah's rank, appointment to positions of muftis without spiritual education in the Orenburg Mohammedan spiritual meeting, creation of obstacles for commission of a hajj to Mecca for mullahs.

  2. Carbon Emission from Forest Fires on Scots Pine Logging Sites in the Angara Region of Central Siberia

    Science.gov (United States)

    Ivanova, G. A.; Conard, S. G.; McRae, D. J.; Kukavskaya, E. A.; Bogorodskaya, A. V.; Kovaleva, N. M.

    2010-12-01

    Wildfire and large-scale forest harvesting are the two major disturbances in the Russian boreal forests. Non-recovered logged sites total about a million hectares in Siberia. Logged sites are characterized by higher fire hazard than forest sites due to the presence of generally untreated logging slash (i.e., available fuel) which dries out much more rapidly compared to understory fuels. Moreover, most logging sites can be easily accessed by local population; this increases the risk for fire ignition. Fire impacts on the overstory trees, subcanopy woody layer, and ground vegetation biomass were estimated on 14 logged and unlogged comparison sites in the Lower Angara Region in 2009-2010 as part of the NASA-funded NEESPI project, The Influence of Changing Forestry Practices on the Effects of Wildfire and on Interactions Between Fire and Changing Climate in Central Siberia. Based on calculated fuel consumption, we estimated carbon emission from fires on both logged and unlogged burned sites. Carbon emission from fires on logged sites appeared to be twice that on unlogged sites. Soil respiration decreased on both site types after fires. This reduction may partially offset fire-produced carbon emissions. Carbon emissions from fire and post-fire ecosystem damage on logged sites are expected to increase under changing climate conditions and as a result of anticipated increases in future forest harvesting in Siberia.

  3. A Serological Survey About Zoonoses in the Verkhoyansk Area, Northeastern Siberia (Sakha Republic, Russian Federation).

    Science.gov (United States)

    Magnaval, Jean-François; Leparc-Goffart, Isabelle; Gibert, Morgane; Gurieva, Alla; Outreville, Jonathan; Dyachkovskaya, Praskovia; Fabre, Richard; Fedorova, Sardana; Nikolaeva, Dariya; Dubois, Damien; Melnitchuk, Olga; Daviaud-Fabre, Pascale; Marty, Marie; Alekseev, Anatoly; Crubezy, Eric

    2016-02-01

    In 2012, a seroprevalence survey concerning 10 zoonoses, which were bacterial (Lyme borreliosis and Q fever), parasitic (alveolar echinococcosis [AE] and cystic echinococcosis [CE], cysticercosis, toxoplasmosis, toxocariasis, and trichinellosis), or arboviral (tick-borne encephalitis and West Nile virus infection), was conducted among 77 adult volunteers inhabiting Suordakh and Tomtor Arctic villages in the Verkhoyansk area (Yakutia). Following serological testing by enzyme-linked immunosorbent assay and/or western blot, no positive result was found for cysticercosis, CE, toxocariasis, trichinellosis, and both arboviral zoonoses. Four subjects (5.2%) had anti-Toxoplasma IgG, without the presence of specific IgM. More importantly, eight subjects (10.4%) tested positive for Lyme borreliosis, two (2.6%) for recently acquired Q fever, and one (1.3%) for AE. Lyme infection and Q fever, whose presence had not been reported so far in Arctic Yakutia, appeared therefore to be a major health threat for people dwelling, sporting, or working in the Arctic area of the Sakha Republic. PMID:26807914

  4. Characterization of particulate organic matter in the Lena River Delta and adjacent nearshore zone, NE Siberia – Part 1: Lignin-derived phenol compositions

    Directory of Open Access Journals (Sweden)

    M. Winterfeld

    2014-10-01

    Full Text Available The Lena River in central Siberia is one of the major pathways translocating terrestrial organic matter (OM from its vast catchment area to the coastal zone of the Laptev Sea and the Arctic Ocean. The permafrost soils of its far south stretching catchment, which store huge amounts of OM, will most likely respond differently to climate warming and remobilize previously frozen OM with distinct properties specific for the source vegetation and soil. To characterize the material discharged by the Lena River, we analyzed the lignin phenol composition in total suspended matter (TSM from surface water collected in spring and summer, surface sediments from the Buor Khaya Bay along with soils from the Lena Delta's first (Holocene and third terraces (Pleistocene ice complex, and plant samples. Our results show that lignin-derived cinnamyl:vanillyl (C/V and syringyl:vanillyl (S/V ratios are >0.14 and 0.25, respectively, in TSM and surface sediments, whereas in delta soils they are >0.16 and >0.51, respectively. These lignin compositions are consistent with significant inputs of organic matter from non-woody angiosperm sources mixed with organic matter derived from woody gymnosperm sources. We applied a simple linear mixing model based on the C/V and S/V ratios and the results indicate the organic matter in delta TSM samples and Buor Khaya Bay surface sediments contain comparable contributions from gymnosperm material, which is primarily derived from the taiga forests south of the delta, and angiosperm material typical for tundra vegetation. Considering the small catchment area covered by tundra (∼12%, the input is substantial and tundra-derived OM input is likely to increase in a warming Arctic. The similar and high acid to aldehyde ratios of vanillyl and syringyl (Ad/AlV, S in Lena Delta summer TSM (>0.7 and >0.5, respectively and Buor Khaya Bay surface sediments (>1.0 and >0.9, respectively suggest that the OM is highly degraded and Lena River summer

  5. Arctic Landfast Sea Ice 1953-1998

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The files in this data set contain landfast sea ice data (monthly means) gathered from both Russian Arctic and Antarctic Research Institute (AARI) and Canadian Ice...

  6. Arctic Marine Transportation Program 1979-1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this program was to collect data relevant to developing year-round transportation capabilities in the Arctic Ocean. The US Maritime Administration...

  7. Acoustic Resonance Reaction Control Thruster (ARCTIC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop and demonstrate the innovative Acoustic Resonance Reaction Control Thruster (ARCTIC) to provide rapid and reliable in-space impulse...

  8. Arctic and Southern Ocean Sea Ice Concentrations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly sea ice concentration for Arctic (1901 to 1995) and Southern oceans (1973 to 1990) were digitized on a standard 1-degree grid (cylindrical projection) to...

  9. Arctic parasitology: why should we care?

    Science.gov (United States)

    Davidson, Rebecca; Simard, Manon; Kutz, Susan J; Kapel, Christian M O; Hamnes, Inger S; Robertson, Lucy J

    2011-06-01

    The significant impact on human and animal health from parasitic infections in tropical regions is well known, but parasites of medical and veterinary importance are also found in the Arctic. Subsistence hunting and inadequate food inspection can expose people of the Arctic to foodborne parasites. Parasitic infections can influence the health of wildlife populations and thereby food security. The low ecological diversity that characterizes the Arctic imparts vulnerability. In addition, parasitic invasions and altered transmission of endemic parasites are evident and anticipated to continue under current climate changes, manifesting as pathogen range expansion, host switching, and/or disease emergence or reduction. However, Arctic ecosystems can provide useful models for understanding climate-induced shifts in host-parasite ecology in other regions.

  10. Geologic Provinces of the Arctic, 2000 (prvarcst)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This coverage includes arcs, polygons and polygon labels that describe Arctic portion of the U.S. Geological Survey defined geologic provinces of the World in 2000.

  11. Arctic climate change: Greenhouse warming unleashed

    Science.gov (United States)

    Mauritsen, Thorsten

    2016-04-01

    Human activity alters the atmospheric composition, which leads to global warming. Model simulations suggest that reductions in emission of sulfur dioxide from Europe since the 1970s could have unveiled rapid Arctic greenhouse gas warming.

  12. Boundary survey, Arctic National Wildlife Range

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is on the geology of the Arctic National Wildlife Range western boundary. The Canning River region and Southern Brooks range are both analyzed,...

  13. Atmospheric dynamics: Arctic winds of change

    Science.gov (United States)

    Notz, Dirk

    2016-09-01

    The Earth's climate evolves in response to both externally forced changes and internal variability. Now research suggests that both drivers combine to set the pace of Arctic warming caused by large-scale sea-ice loss.

  14. Revegetation techniques in arctic and subarctic environments

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the revegetation techniques in the arctic and subarctic environments. Background on the subject, as well as a literature reviews concerning...

  15. Politics of sustainability in the Arctic (POSUSA)

    DEFF Research Database (Denmark)

    Gad, Ulrik Pram; Jakobsen, Uffe; Strandsbjerg, Jeppe

    The concept of sustainability is of central importance in Arctic politics. However, for different actors (governments, indigenious peoples, NGOs) the concept implies different sets of precautions and opportunities. Sustainability, therefore, is much more a fundamental concept to be further elabor...

  16. Arctic and Aleutian terns, Amchitka Island, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Baird (1980) has recently reported on the ecology of Arctic terns (Sterna paradisaea) and Aleutian terns (Sterna aleutica) from 4 areas of mainland Alaska. However,...

  17. Distribution of GHG over West Siberia: airborne and tower network observations.

    Science.gov (United States)

    Arshinov, M. Yu.; Machida, T.; Inoue, G.; Belan, B. D.; Maksyutov, Sh.; Sasakawa, M.; Watai, T.; Shimoyama, K.; Sutoh, H.; Davydov, D. K.

    2009-04-01

    In spite of high confidence level in understanding of greenhouse effect on climate change there is a lack of measurement data over significant part of the Northern Hemisphere. Taking into account the importance of the global climate changes and international cooperation in this field, NIES (National Institute for Environmental Studies) and IAO (Institute of Atmospheric Optics) combined their efforts in the framework of Joint Japanese-Russian Project on GHG monitoring to fill up this gap at least over West Siberia, which occupies a significant part of Northern Eurasia. This monitoring consists of airborne and tower network observations. Airborne study of vertical distribution of greenhouse gases nearby Novosibirsk (between 54°05'N-81°50'E and 54°35'N-82°40'E) has been started on July 1997. Monthly flight observation have been conducted at an altitude from 500 to 7000 km. The 11-year airborne study nearby Novosibirsk has revealed a positive trend in CO2 mixing ratio (>15 ppm) and the absence of a definite trend for CH4. Minimum of CO2 concentration is typically observed at the end of July. Highest annual amplitudes of CO2 mixing ratio (up to 40 ppm) are observed in the atmospheric boundary layer. During recent years a tower network (8 towers) for carbon dioxide and methane monitoring was established in West Siberia. This network covers several climatic zones from steppes in the south to northern taiga in the north (51°N to 63°N and 62°E to 82°E). In this paper we present the first results of the diurnal, seasonal, and annual behavior of these greenhouse gases in the surface atmospheric layer over West Siberia Diurnal behavior of CO2 mixing ratio showed its maximum amplitude in July and its minimum amplitude in January. Concentration gradient between northern and southern regions remains during the whole year. Carbon dioxide mixing ratio has a pronounced annual behavior with a maximum in December and a minimum in July-August. It starts to decrease on March

  18. A reconstruction of vegetation and paleohydrologycal changes from peatland in Kansk forest-steppe, Yenisei Siberia

    Science.gov (United States)

    Rodionova, Alexandra

    2016-04-01

    Peatlands are an important natural archive for past climatic changes. Climatic changes throughout the Holocene have been reconstructed from peat using a wide array of biological and other proxies. Many different proxy indicators can be derived from peat cores allowing for a multi-proxy approach to climatic reconstructions. Peat-based climatic and environmental reconstructions are currently available from many sites in Yenisei Siberia, mainly for its northern territories. The purpose of this paper is to study some features of peatland development and environmental reconstructions from the Holocene period in the south part of Yenisei Siberia (Kansk forest-steppe zone). The main method used in this research is macrofossil analysis. It can be used to reconstruct the development of local vegetation and surface wetness on peatlands. The macrofossil analysis in the peat resulted from the study of the vegetation in a particular place over a period of time, and it allowed the reconstruction of environmental changes that have occurred since the Late Glacial. Then we used ecological scales of moisture and reconstructed surface wetness for the entire period of the bog formation. Radiocarbon dating was carried out at Sobolev Institute of Geology and Mineralogy, Russian Academy of Sciences, Novosibirsk . Peatland "Pinchinskoye" was selected for investigation in Kansk forest-steppe. It is located on the right bank of the Yenisei River in the floodplain of Esaulovka River. Peat cores of 350 cm were selected in the southern part of the peatbog, including 225 cm of peat (with loam layers in the range of 90 to 135 cm), 75 cm of organic and mineral sapropel with the inclusion of fossil shells of mollusks and different plant macrofossils and 50 cm of the loam below. The process of peat accumulation dated back 8400 ± 140 years, which is the oldest date for the forest-steppe zone of Yenisei Siberia. The climate of Boreal period of the Holocene was chilly. Under these conditions, in the

  19. Arctic shipping emissions inventories and future scenarios

    OpenAIRE

    J. J. Corbett; D. A. Lack; J. J. Winebrake; Harder, S; J. A. Silberman; Gold, M.

    2010-01-01

    This paper presents 5 km×5 km Arctic emissions inventories of important greenhouse gases, black carbon and other pollutants under existing and future (2050) scenarios that account for growth of shipping in the region, potential diversion traffic through emerging routes, and possible emissions control measures. These high-resolution, geospatial emissions inventories for shipping can be used to evaluate Arctic climate sensitivity to black carbon (a short-lived climate forcing pollutant especial...

  20. Isotopes in the Arctic atmospheric water cycle

    OpenAIRE

    Bonne, Jean-Louis; Werner, Martin; Meyer, Hanno; Kipfstuhl, Sepp; Rabe, Benjamin; Behrens, Melanie; Schönicke, Lutz; Steen-Larsen, Hans Christian; Masson-Delmotte, Valérie

    2016-01-01

    The ISO-ARC project aims at documenting the Arctic atmospheric hydrological cycle, by assessing the imprint of the marine boundary conditions (e.g. temperature variations, circulation changes, or meltwater input) to the isotopic composition of the atmospheric water cycle (H218O and HDO) with a focus on North Atlantic and Arctic oceans. For this purpose, two continuous monitoring water vapour stable isotopes cavity ring-down spectrometers have been installed in July 2015: on-boar...

  1. Studying ocean acidification in the Arctic Ocean

    Science.gov (United States)

    Robbins, Lisa

    2012-01-01

    The U.S. Geological Survey (USGS) partnership with the U.S. Coast Guard Ice Breaker Healey and its United Nations Convention Law of the Sea (UNCLOS) cruises has produced new synoptic data from samples collected in the Arctic Ocean and insights into the patterns and extent of ocean acidification. This framework of foundational geochemical information will help inform our understanding of potential risks to Arctic resources due to ocean acidification.

  2. The Anatomy of an Arctic Knowledge Debate

    DEFF Research Database (Denmark)

    Sejersen, Frank

    2005-01-01

    Within the last decades, the Arctic research community and the Inuit communities have focused on the question of knowledge to such an extent that we may in fact speak of a knowledge cult.......Within the last decades, the Arctic research community and the Inuit communities have focused on the question of knowledge to such an extent that we may in fact speak of a knowledge cult....

  3. Land-Based Marine Pollution in Arctic

    OpenAIRE

    Haile, Fitsum Gebreselassie

    2014-01-01

    Land-based pollution represents the single most important cause of marine pollution. The threat of land-based pollution to the marine environment is a serious one since it mainly affects coastal waters, which are sites of high biological productivity. The occurrence of high concentrations of pollutants in the Arctic environment has been a concern for many years.. Regional and international actions over the past two decades attempting to manage pollutants in the Arctic environment from land- b...

  4. Research on Operational Characteristics of Imported Rails under Conditions of East Siberian Railway

    Science.gov (United States)

    Gizatulin, R. A.; Kozyrev, N. A.; Valuev, D. V.; Valueva, A. V.; Serikbol, A.

    2016-04-01

    In world’s manufacturing of railroad rails there are several thermal bonding methods: differentiated waterflow quenching, air-blast or spray quenching, rail head’s hardening in polymer solution and bulk oil hardening; rails’ service durability is strongly dependent on thermo-hardening methods. Until recently, all of rails, produced at Nizhniy Tagil and Kuznetsk Metallurgical Works, were subjected to bulk oil hardening. Only in 2010-2011, in the Russian Federation, differentiated air quenching of rails was started at the JSC “EVRAZ ZSMK” and rail heads’ hardening in polymer solution - at the JSC “Mechel”. At the same time, exploitation of imported rails with differentiated hardening has been performed on Russian railways since 1995. Service durability of these rails in Siberia and the Far North is of considerable interest. In this paper we investigated the quality of P65-type rails, made in Japan, removed after use from curved track section of the East-Siberian railway.

  5. Arctic Ocean data in CARINA

    Directory of Open Access Journals (Sweden)

    S. Jutterström

    2010-02-01

    Full Text Available The paper describes the steps taken for quality controlling chosen parameters within the Arctic Ocean data included in the CARINA data set and checking for offsets between the individual cruises. The evaluated parameters are the inorganic carbon parameters (total dissolved inorganic carbon, total alkalinity and pH, oxygen and nutrients: nitrate, phosphate and silicate. More parameters can be found in the CARINA data product, but were not subject to a secondary quality control. The main method in determining offsets between cruises was regional multi-linear regression, after a first rough basin-wide deep-water estimate of each parameter. Lastly, the results of the secondary quality control are discussed as well as applied adjustments.

  6. Arctic Ocean data in CARINA

    Directory of Open Access Journals (Sweden)

    S. Jutterström

    2009-08-01

    Full Text Available The paper describes the steps taken for quality controlling chosen parameters within the Arctic Ocean data included in the CARINA data set and checking for offsets between the individual cruises. The evaluated parameters are the inorganic carbon parameters (total dissolved inorganic carbon, total alkalinity and pH, oxygen and nutrients: nitrate, phosphate and silicate. More parameters can be found in the CARINA data product, but were not subject to a secondary quality control. The main method in determining offsets between cruises was regional multi-linear regression, after a first rough basin-wide deep-water estimate of each parameter. Lastly, the results of the secondary quality control are discussed as well as suggested adjustments.

  7. Changes in CO_{2} trends observed in the lower troposphere over West Siberia

    Science.gov (United States)

    Belan, Boris D.; Machida, Toshinobu; Sasakawa, Motoki; Maksyutov, Shamil; Davydov, Denis; Fofonov, Alexandr; Arshinov, Mikhail

    2016-04-01

    Long-term airborne observations of greenhouse gases carried out in the troposphere over south-western area of West Siberia since 1997 allowed some specific features in CO2 trends to be revealed at different heights. At an altitude of 7 km above ground level (AGL), the average annual rate of CO2 increase was 1.72 ppm yr‑1. The main distinctive features in the tendencies of CO2 mixing ratio have been found in the lower troposphere. Thus, for the period from 1997 to 2004, July concentrations of CO2 at an altitude of 500 m AGL increased slightly with a rate of 0.17 ppm yr‑1, while since 2005 they began to rise dramatically with a rate of 3.64 ppm yr‑1. Analysis of the possible causes of such long-term behavior showed that it was resulted from neither reduction of forest area, nor wildfires, nor forest diseases. Also it is impossible to state that reducing CO2 sink has been caused by the impact of climate changes on ecosystems. Possibly, anthropogenic CO2 accumulation resulted in that Siberian forests cannot assimilate such additional amount of carbon dioxide. A decrease in the sink for atmospheric CO2 is also observed in the Amazon (Brienen et al. 2015). Brienen et al. (2015) assume that it may be caused by a sustained long-term increase in tree mortality. There is also a supposition that it can be a result of a vegetation replacement by other types of plants or young trees, which absorb less amount of CO2 (Kunstler et al., 2015; Crowther T. W., 2015). However, it seems highly unlikely to test these hyposeses in the near future due to a huge area of West Siberia, most regions of which are difficult to access. This work was funded by the Global Environment Research Account for National Institutes of the Ministry of the Environment (Japan) and Russian Foundation for Basic Research (grant No. 14-05-00590). Brienen R.J.W. et al. 2015. Long-term decline of the Amazon carbon sink. Nature. 519 (7543), 344-348. Kunstler G. et al. 2015. Plant functional traits have

  8. Changes in CO_{2} trends observed in the lower troposphere over West Siberia

    Science.gov (United States)

    Belan, Boris D.; Machida, Toshinobu; Sasakawa, Motoki; Maksyutov, Shamil; Davydov, Denis; Fofonov, Alexandr; Arshinov, Mikhail

    2016-04-01

    Long-term airborne observations of greenhouse gases carried out in the troposphere over south-western area of West Siberia since 1997 allowed some specific features in CO2 trends to be revealed at different heights. At an altitude of 7 km above ground level (AGL), the average annual rate of CO2 increase was 1.72 ppm yr-1. The main distinctive features in the tendencies of CO2 mixing ratio have been found in the lower troposphere. Thus, for the period from 1997 to 2004, July concentrations of CO2 at an altitude of 500 m AGL increased slightly with a rate of 0.17 ppm yr-1, while since 2005 they began to rise dramatically with a rate of 3.64 ppm yr-1. Analysis of the possible causes of such long-term behavior showed that it was resulted from neither reduction of forest area, nor wildfires, nor forest diseases. Also it is impossible to state that reducing CO2 sink has been caused by the impact of climate changes on ecosystems. Possibly, anthropogenic CO2 accumulation resulted in that Siberian forests cannot assimilate such additional amount of carbon dioxide. A decrease in the sink for atmospheric CO2 is also observed in the Amazon (Brienen et al. 2015). Brienen et al. (2015) assume that it may be caused by a sustained long-term increase in tree mortality. There is also a supposition that it can be a result of a vegetation replacement by other types of plants or young trees, which absorb less amount of CO2 (Kunstler et al., 2015; Crowther T. W., 2015). However, it seems highly unlikely to test these hyposeses in the near future due to a huge area of West Siberia, most regions of which are difficult to access. This work was funded by the Global Environment Research Account for National Institutes of the Ministry of the Environment (Japan) and Russian Foundation for Basic Research (grant No. 14-05-00590). Brienen R.J.W. et al. 2015. Long-term decline of the Amazon carbon sink. Nature. 519 (7543), 344-348. Kunstler G. et al. 2015. Plant functional traits have globally

  9. Zn isotope fractionation in a pristine larch forest on permafrost-dominated soils in Central Siberia.

    Science.gov (United States)

    Viers, Jerome; Prokushkin, Anatoly S; Pokrovsky, Oleg S; Kirdyanov, Alexander V; Zouiten, Cyril; Chmeleff, Jerome; Meheut, Merlin; Chabaux, Francois; Oliva, Priscia; Dupré, Bernard

    2015-01-01

    Stable Zn isotopes fractionation was studied in main biogeochemical compartments of a pristine larch forest of Central Siberia developed over continuous permafrost basalt rocks. Two north- and south-oriented watershed slopes having distinctly different vegetation biomass and active layer depth were used as natural proxy for predicting possible future climate changes occurring in this region. In addition, peat bog zone exhibiting totally different vegetation, hydrology and soil temperature regime has been studied. The isotopic composition of soil profile from Central Siberia is rather constant with a δ(66)Zn value around 0.2‰ close to the value of various basalts. Zn isotopic composition in mosses (Sphagnum fuscum and Pleurozium schreberi) exhibits differences between surface layers presenting values from 0.14 to 0.2‰ and bottom layers presenting significantly higher values (0.5 - 0.7‰) than the underlain mineral surface. The humification of both dead moss and larch needles leads to retain the fraction where Zn bound most strongly thus releasing the lighter isotopes in solution and preserving the heavy isotopes in the humification products, in general accord with previous experimental and modeling works [GCA 75:7632-7643, 2011]. The larch (Larix gmelinii) from North and South-facing slopes is enriched in heavy isotopes compared to soil reservoir while larch from Sphagnum peatbog is enriched in light isotopes. This difference may result from stronger complexation of Zn by organic ligands and humification products in the peat bog compared to mineral surfaces in North- and South-facing slope. During the course of the growing period, Zn followed the behavior of macronutrients with a decrease of concentration from June to September. During this period, an enrichment of larch needles by heavier Zn isotopes is observed in the various habitats. We suggest that the increase of the depth of rooting zone, and the decrease of DOC and Zn concentration in soil solution

  10. Post-fire succession of ground vegetation of central Siberia in Scots pine forests

    Science.gov (United States)

    Kovaleva, N.; Ivanova, G. A.; Conard, S. G.

    2012-04-01

    Extensive wildfires have affected the Russian region in the last decade. Scots pine forests (Pinus sylvestris L.) are widespread in central Siberia and fire occurrence is high in these forests, whose dominant fire regime is one of frequent surface fires. We studied post- fire succession of ground vegetation has been studied on nine experimental fires of varying severity (from 620 to 5220 kW/m) in middle taiga Scots pine forests of central Siberia (Russia). It proved from our study that all species of the succession process are present from initial stages. We did not find any trend of ground vegetation diversity with the time during 8 years after the fire. Our investigation showed that post- fire recovery of the ground vegetation is determined by initial forest type, fire severity and litter burning depth. Fire severity had a clear effect in initial succession in study area and it clearly had an impact on percentage cover, biomass and structure of ground vegetation. In a lesser degree the small shrubs are damaged during ground fires. The dominating species (Vaccinium vitis-idaea and V. myrtillus) regained the cover values above or close to 6—8 years. The post- fire biomass of ground vegetation 93—100% consists of species (Vaccinium vitis-idaea and V. myrtillus) that survived after the fire and increased in the cover with the time. In pine forests mosses and lichens suffer to a greater degree after ground fires. Lichen layer was completely lost after the fires of any severity. Decrease of mosses species diversity takes place after ground fires. The post- fire cover and species diversity of the green mosses were progressively lower with increasing the fire severity during the observation period. Maximum changes are discovered in the post- fire structure of plant microgroups after the high- severity fire which resulted in intensive invasion by the post- fire mosses (Polytrichum strictum and P. commune). There is a positive trend of green moss microgroups recovery

  11. Trace elements transport in western Siberia rivers across a permafrost gradient

    Directory of Open Access Journals (Sweden)

    O. S. Pokrovsky

    2015-11-01

    Full Text Available Towards a better understanding of trace element transport in permafrost-affected Earth surface environments, we sampled ∼ 60 large and small rivers (2 watershed area of Western Siberia Lowland (WSL during spring flood and summer and winter base-flow across a 1500 km latitudinal gradient covering continuous, discontinuous, sporadic and permafrost-free zones. Analysis of ∼ 40 major and trace elements in dissolved ( The Principal Component Analysis demonstrated two main factors potentially controlling the ensemble of TE concentration variation. The first factor, responsible for 16–20 % of overall variation, included trivalent and tetravalent hydrolysates, Cr, V, and DOC and presumably reflected the presence of organo-mineral colloids, as also confirmed by previous studies in Siberian rivers. The 2nd factor (8–14 % variation was linked to the latitude of the watershed and acted on elements affected by the groundwater feeding (DIC, Sr, Mo, As, Sb, U, whose concentration decreased significantly northward during all seasons. Overall, the rank of environmental factors on TE concentration in western Siberian rivers was latitude (3 permafrost zones > season > watershed size. The effect of the latitude was minimal in spring for most TE but highly visible for Sr, Mo, Sb and U. The main factors controlling the shift of river feeding from surface and subsurface flow to deep underground flow in the permafrost-bearing zone were the depth of the active (unfrozen seasonal layer and its position in organic or mineral horizons of the soil profile. In the permafrost-free zone, the relative role of carbonate mineral-bearing base rock feeding vs. bog water feeding determined the pattern of trace element concentration and fluxes in rivers of various size as a function of season. Comparison of obtained TE fluxes in WSL rivers with those of other subarctic rivers demonstrated reasonable agreement for most trace elements; the lithology of base rocks was the major

  12. Physical processes of thermokarst lakes in the continuous permafrost zone of northern Siberia – observations and modeling (Lena River Delta, Siberia

    Directory of Open Access Journals (Sweden)

    J. Boike

    2015-04-01

    Full Text Available The thermal regimes of five lakes located within the continuous permafrost zone of northern Siberia (Lena River Delta have been investigated using hourly water temperature and water level records covering a three year period (2009–2012, together with bathymetric survey data. The lakes included thermokarst lakes located on Holocene river terraces that may be connected to Lena River water during spring flooding, and a thermokarst lake located on deposits of the Pleistocene Ice Complex. The data were used for numerical modeling with FLake software, and also to determine the physical indices of the lakes. The lakes vary in area, depths and volumes. The winter thermal regime is characterized by an ice cover up to 2 m thick that survives for more than 7 months of the year, from October until about mid-June. Lake-bottom temperatures increase at the start of the ice-covered period due to upward-directed heat flux from the underlying thawed sediment. The effects of solar radiation return prior to ice break-up, effectively warming the water beneath the ice cover and inducing convective mixing. Ice break-up starts the beginning of June and takes until the middle or end of June for completion. Mixing occurs within the entire water column from the start of ice break-up and continues during the ice-free periods, as confirmed by the Wedderburn numbers. Some of the lakes located closest to the Lena River are subjected to varying levels of spring flooding with river water, on an annual basis. Numerical modeling using FLake software indicates that the vertical heat flux across the bottom sediment tends towards an annual mean of zero, with maximum downward fluxes of about 5 W m−2 in summer and with heat released back into the water column at a~rate of less than 1 W m−2 during the ice-covered period. The lakes are shown to be efficient heat absorbers and effectively distribute the heat through mixing. Monthly bottom water temperatures during the ice

  13. Observation of surface ozone in the marine boundary layer along a cruise through the Arctic Ocean: From offshore to remote

    Science.gov (United States)

    He, Pengzhen; Bian, Lingen; Zheng, Xiangdong; Yu, Juan; Sun, Chen; Ye, Peipei; Xie, Zhouqing

    2016-03-01

    Ozone is an important reactive gas in the troposphere; it has been frequently used to estimate atmospheric oxidation capacity. However, there are few data of surface ozone over the Arctic Ocean, especially the central Arctic Ocean. Here, surface ozone in the marine boundary layer along the cruise path during the 5th Chinese Arctic Research Expedition (June to September, 2012) was investigated. The latitudes and longitudes covered in the cruise were 31.1°N-87.7°N and 9.3°E-90°E-168.4°W. The 1-h-averaged ozone varied from 9.4 ppbv to 124.5 ppbv along the cruise. The highest mixing ratios appeared in the East China Sea and the Sea of Japan while the lowest in the Chukchi Sea. The relatively high ozone levels over the East China Sea, the Sea of Japan, and offshore Iceland were caused by transport of precursors and/or ozone from the nearby continent. Ozone mixing ratio decreasing by ~ 2 ppbv/° with increasing latitude was observed during 31-45°N covering the East China Sea and the Sea of Japan, and during 62-69°N covering offshore Iceland. Over the entire Arctic Ocean, ozone levels were relatively low, varying from 9.4 ppbv to 36.1 ppbv with an average of 23.8 ± 4.6 (mean ± standard deviation) ppbv, which was not statistically different with data observed at Barrow observatory during the same period. Unlike ozone over contaminated areas, a slight increasing trend of ozone in 69-87°N was observed. This phenomenon may be ascribed to the role of both vertical transport and chemical processes due to solar radiation.

  14. Arctic response strategy: Canadian Coast Guard

    International Nuclear Information System (INIS)

    The revision of the Canadian Coast Guard's Arctic response strategy was described with particular focus on the consultative method used to ensure that all perspectives were taken into consideration. Some tankers used to re-supply fuel to remote Arctic communities carry more than 30,000 tonnes of product, putting them at risk for major spills. The Arctic response strategy was revised to emphasize recommendations for prevention, preparedness and response. Prevention was recognized as the most effective solution to oil spills in the Arctic. The leadership and coordination roles of the Canadian Coast Guard were demonstrated in relation to ship-source oil pollution. The new strategy also outlined the equipment requirements needed to respond to a large spill in the Arctic. Categorization of spill sizes as tier 1 to 4 was determined by examining southern regimes as was the characterization of corresponding equipment. Implementation of the new recommendations of the revised Arctic response strategy will take place over the next 2 years. The prevention aspect will include some legislative changes or stricter guidelines

  15. Powassan virus in mammals, Alaska and New Mexico, USA, and Russia, 2004–2007

    Science.gov (United States)

    Deardorff, Eleanor R.; Nofchissey, Robert A.; Cook, Joseph A.; Hope, Andrew G.; Tsvetkova, Albina; Talbot, Sandra L.; Ebel, Gregory D.

    2013-01-01

    Powassan virus is endemic to the United States, Canada, and the Russian Far East. We report serologic evidence of circulation of this virus in Alaska, New Mexico, and Siberia. These data support further studies of viral ecology in rapidly changing Arctic environments.

  16. Powassan Virus in Mammals, Alaska and New Mexico, USA, and Russia, 2004–2007

    OpenAIRE

    Deardorff, Eleanor R.; Nofchissey, Robert A.; Cook, Joseph A.; Hope, Andrew G.; Tsvetkova, Albina; Talbot, Sandra L.; Ebel, Gregory D.

    2013-01-01

    Powassan virus is endemic to the United States, Canada, and the Russian Far East. We report serologic evidence of circulation of this virus in Alaska, New Mexico, and Siberia. These data support further studies of viral ecology in rapidly changing Arctic environments.

  17. World review: Middle East

    International Nuclear Information System (INIS)

    The article gives information on contracts announced (and to whom) and recently completed in some parts of the Middle East in the petroleum, natural gas and petrochemicals industries. Areas specifically mentioned are Bahrain, Egypt, Iran, Libya, Oman, Qatar, Saudi Arabia, Syria and the United Arab Emirates. The prospects for the petrochemical industry in particular are good and continued growth is expected. Gas is likely to make an increasingly important contribution to the prosperity of the Middle East and is expected to carry a higher priority than expansion of crude oil production

  18. Trace element concentrations and gastrointestinal parasites of Arctic terns breeding in the Canadian High Arctic.

    Science.gov (United States)

    Provencher, J F; Braune, B M; Gilchrist, H G; Forbes, M R; Mallory, M L

    2014-04-01

    Baseline data on trace element concentrations are lacking for many species of Arctic marine birds. We measured essential and non-essential element concentrations in Arctic tern (Sterna paradisaea) liver tissue and brain tissue (mercury only) from Canada's High Arctic, and recorded the presence/absence of gastrointestinal parasites during four different phases of the breeding season. Arctic terns from northern Canada had similar trace element concentrations to other seabird species feeding at the same trophic level in the same region. Concentrations of bismuth, selenium, lead and mercury in Arctic terns were high compared to published threshold values for birds. Selenium and mercury concentrations were also higher in Arctic terns from northern Canada than bird species sampled in other Arctic areas. Selenium, mercury and arsenic concentrations varied across the time periods examined, suggesting potential regional differences in the exposure of biota to these elements. For unknown reasons, selenium concentrations were significantly higher in birds with gastrointestinal parasites as compared to those without parasites, while bismuth concentrations were higher in Arctic terns not infected with gastrointestinal parasites.

  19. 俄罗斯北极地区中生代岩相古地理特征及油气资源潜力分析%Evolution of lithofacies paleogeography of Mesozoic and hydrocarbon resources potential analysis in Russian Arctic area

    Institute of Scientific and Technical Information of China (English)

    刘恩然; 辛仁臣; 何虎庄

    2015-01-01

    .Combined with the exploration results, the hydrocarbon potential is analyzed.In Triassic, most of the study region is littoral facies and neritic facies.Sediments are dominated by the combination of volcanic rock and clastic rock.Uplift-erosion facies mainly are distributed in the Aldan Shield and its east .The structure unit is around Novaya Zemlya-Ural Fold Belt and East Siberia Platform.In Jurassic, most of the study region is neritic facies.Sediments are dominated by the combinations of sand and mud.Uplift-erosion facies grew in the East Siberia Platform.During early Cre-taceous, neritic facies were distributed in the study region.Sediments are dominated by the combination of sand and mud.Uplift-erosion facies increased one third in Okhotsk Massif-East Siberian Sea Basin and the area a-round them.In late Cretaceous, most of the study region became uplift-erosion facies, neritic facies took the second place.Amerasian basin began to form.Sediments are dominated by the combination of sand and mud. Novo Sibirsko-Chukotka Fold Belt became uplift-erosion facies.The result shows that (1) Sand-mud combi-nation is the main lithologic features of Mesozoic.Volcanic rock and clastic rock combination, conglomerate-sand-mud combination and sand-mud -carbonate combination took the second place.(2) Paleogeography features of Triassic and Jurassic are mainly neritic facies.However, the uplift-erosion facies grew under the in-fluence of the collision between Novosibirsk-Hukchi Alaska microplate and the north Okhotsk crustal block in Early Cretaceous, hence the uplift-erosion facies dominated the research filed in Late Cretaceous.( 3 ) The East Barents Sea Basin Jurassic formation, the formation of north sea of West Siberian basin in Cretaceous, the formation of north of Kara sea in Cretaceous and Jurassic are important regions for hydrocarbon exploration. Yenisey-Khatanga Basin, Laptev Sea Basin and East Siberian Basin are also good places for oil exploration, especially in their Jurassic

  20. 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.