An International Polar Year Adventure in the Arctic

Science.gov (United States)

Wartes, D.

2008-12-01

Native students in the UA system who participated in RAHI are nearly twice as likely to earn a bachelor's degree, than those who did not attend RAHI. The past two summers, in celebration of the International Polar Year, in collaboration with Ilisagvik College, at the completion of the traditional RAHI program, ten RAHI students flew to Barrow for an additional two weeks of study. Five students participated in an archaeological dig and five students performed research with the Barrow Arctic Science Consortium scientists studying climate change. And another student was the Alaskan delegate to the Students on Ice, a 2-week ship-based adventure in northern Canada. In addition, ten students from Greenland visited the program, with plans to more fully participate next summer. This added dimension to the program has proved successful, allowing the students to compare and contrast between their own countries and indigenous perspectives. Global warming was an issue that was hotly debated, as its effects are so evident in the Polar Regions. In the Arctic, one's life is directly tied to the ice and snow. As the ice disappears and/or changes, the Indigenous people have to adapt. RAHI would like to share with you some of the results of this past summer's IPY activities.

To the Extremes! A Teacher Research Experience Program in the Polar Regions

Science.gov (United States)

Warburton, J.; Bartholow, S.

2014-12-01

PolarTREC-Teachers and Researchers Exploring and Collaborating, a teacher professional development program, began with the International Polar Year in 2004 and continues today in the United States. In 2007, the National Science Foundation designated PolarTREC as potentially transformative, meaning that the "research results often do not fit within established models or theories and may initially be unexpected or difficult to interpret; their transformative nature and utility might not be recognized until years later." PolarTREC brings U.S. K-12 educators and polar researchers together through an innovative teacher research experience model. Teachers spend three to six weeks in remote arctic and Antarctic field camps. Since 2007, over 100 teachers have been placed in field experiences throughout the Arctic and Antarctic and with half of them participating in field experiences in Antarctica. During their experience, teachers become research team members filling a variety of roles on the team. They also fulfil a unique role of public outreach officer, conducting live presentations about their field site and research as well as journaling, answering questions, and posting photos. Evaluation data collected over the past eight years on program participants shows that PolarTREC has clearly achieved it goals and strongly suggests programs that link teachers and researchers can have the potential to transform the nature of science education. By giving teachers the content knowledge, pedagogical tools, confidence, understanding of science in the broader society, and experiences with scientific inquiry, participating teachers are using authentic scientific research in their classrooms. Not surprisingly this has also led to increases in student interest and knowledge about the Polar Regions. In this presentation, we will highlight the best practices of teacher research experiences as well as discuss why it is vital to have teachers and researchers work together to communicate

NSF Antarctic and Arctic Data Consortium; Scientific Research Support & Data Services for the Polar Community

Science.gov (United States)

Morin, P. J.; Pundsack, J. W.; Carbotte, S. M.; Tweedie, C. E.; Grunow, A.; Lazzara, M. A.; Carpenter, P.; Sjunneskog, C. M.; Yarmey, L.; Bauer, R.; Adrian, B. M.; Pettit, J.

2014-12-01

The U.S. National Science Foundation Antarctic & Arctic Data Consortium (a2dc) is a collaboration of research centers and support organizations that provide polar scientists with data and tools to complete their research objectives. From searching historical weather observations to submitting geologic samples, polar researchers utilize the a2dc to search andcontribute to the wealth of polar scientific and geospatial data.The goals of the Antarctic & Arctic Data Consortium are to increase visibility in the research community of the services provided by resource and support facilities. Closer integration of individual facilities into a "one stop shop" will make it easier for researchers to take advantage of services and products provided by consortium members. The a2dc provides a common web portal where investigators can go to access data and samples needed to build research projects, develop student projects, or to do virtual field reconnaissance without having to utilize expensive logistics to go into the field.Participation by the international community is crucial for the success of a2dc. There are 48 nations that are signatories of the Antarctic Treaty, and 8 sovereign nations in the Arctic. Many of these organizations have unique capabilities and data that would benefit US ­funded polar science and vice versa.We'll present an overview of the Antarctic & Arctic Data Consortium, current participating organizations, challenges & opportunities, and plans to better coordinate data through a geospatial strategy and infrastructure.

Pacific Northwest Laboratory Alaska (ARCTIC) research program

International Nuclear Information System (INIS)

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

Building AN International Polar Data Coordination Network

Science.gov (United States)

Pulsifer, P. L.; Yarmey, L.; Manley, W. F.; Gaylord, A. G.; Tweedie, C. E.

2013-12-01

In the spirit of the World Data Center system developed to manage data resulting from the International Geophysical Year of 1957-58, the International Polar Year 2007-2009 (IPY) resulted in significant progress towards establishing an international polar data management network. However, a sustained international network is still evolving. In this paper we argue that the fundamental building blocks for such a network exist and that the time is right to move forward. We focus on the Arctic component of such a network with linkages to Antarctic network building activities. A review of an important set of Network building blocks is presented: i) the legacy of the IPY data and information service; ii) global data management services with a polar component (e.g. World Data System); iii) regional systems (e.g. Arctic Observing Viewer; iv) nationally focused programs (e.g. Arctic Observing Viewer, Advanced Cooperative Arctic Data and Information Service, Polar Data Catalogue, Inuit Knowledge Centre); v) programs focused on the local (e.g. Exchange for Local Observations and Knowledge of the Arctic, Geomatics and Cartographic Research Centre). We discuss current activities and results with respect to three priority areas needed to establish a strong and effective Network. First, a summary of network building activities reports on a series of productive meetings, including the Arctic Observing Summit and the Polar Data Forum, that have resulted in a core set of Network nodes and participants and a refined vision for the Network. Second, we recognize that interoperability for information sharing fundamentally relies on the creation and adoption of community-based data description standards and data delivery mechanisms. There is a broad range of interoperability frameworks and specifications available; however, these need to be adapted for polar community needs. Progress towards Network interoperability is reviewed, and a prototype distributed data systems is demonstrated. We

Advancing NOAA NWS Arctic Program Development

Science.gov (United States)

Timofeyeva-Livezey, M. M.; Horsfall, F. M. C.; Meyers, J. C.; Churma, M.; Thoman, R.

2016-12-01

Environmental changes in the Arctic require changes in the way the National Oceanic and Atmospheric Administration (NOAA) delivers hydrological and meteorological information to prepare the region's societies and indigenous population for emerging challenges. These challenges include changing weather patterns, changes in the timing and extent of sea ice, accelerated soil erosion due to permafrost decline, increasing coastal vulnerably, and changes in the traditional food supply. The decline in Arctic sea ice is opening new opportunities for exploitation of natural resources, commerce, tourism, and military interest. These societal challenges and economic opportunities call for a NOAA integrated approach for delivery of environmental information including climate, water, and weather data, forecasts, and warnings. Presently the NOAA Arctic Task Force provides leadership in programmatic coordination across NOAA line offices. National Weather Service (NWS) Alaska Region and the National Centers for Environmental Prediction (NCEP) provide the foundational operational hydro-meteorological products and services in the Arctic. Starting in 2016, NOAA's NWS will work toward improving its role in programmatic coordination and development through assembling an NWS Arctic Task Team. The team will foster ties in the Arctic between the 11 NWS national service programs in climate, water, and weather information, as well as between Arctic programs in NWS and other NOAA line offices and external partners. One of the team outcomes is improving decision support tools for the Arctic. The Local Climate Analysis Tool (LCAT) currently has more than 1100 registered users, including NOAA staff and technical partners. The tool has been available online since 2013 (http://nws.weather.gov/lcat/ ). The tool links trusted, recommended NOAA data and analytical capabilities to assess impacts of climate variability and climate change at local levels. A new capability currently being developed will

Possible Effects of Climate Warming on Selected Populations of Polar Bears (Ursus maritimus) in the Canadian Arctic

Science.gov (United States)

Parkinson, Claire L.; Stirling Ian

2006-01-01

Polar bears are dependent on sea ice for survival. Climate warming in the Arctic has caused significant declines in coverage and thickness of sea ice in the polar basin and progressively earlier breakup in some areas. In four populations of polar bears in the eastern Canadian Arctic (including Western Hudson Bay), Inuit hunters report more bears near settlements during the open water period in recent years. These observations have been interpreted as evidence of increasing population size, resulting in increases in hunting quotas. However, long-term data on the population size and condition of polar bears in Western Hudson Bay, and population and harvest data from Baffin Bay, make it clear that those two populations at least are declining, not increasing. While the details vary in different arctic regions, analysis of passive-microwave satellite imagery, beginning in the late 1970s, indicates that the sea ice is breaking up at progressively earlier dates, so that bears must fast for longer periods during the open water season. Thus, at least part of the explanation for the appearance of more bears in coastal communities is likely that they are searching for alternative food sources because their stored body fat depots are being exhausted. We hypothesize that, if the climate continues to warm as projected by the IPCC, then polar bears in all five populations discussed in this paper will be stressed and are likely to decline in numbers, probably significantly so. As these populations decline, there will likely also be continuing, possibly increasing, numbers of problem interactions between bears and humans as the bears seek alternate food sources. Taken together, the data reported in this paper suggest that a precautionary approach be taken to the harvesting of polar bears and that the potential effects of climate warming be incorporated into planning for the management and conservation of this species throughout the Arctic.

'Unstructured Data' Practices in Polar Institutions and Networks: a Case Study with the Arctic Options Project

Directory of Open Access Journals (Sweden)

Paul Arthur Berkman

2014-10-01

Full Text Available Arctic Options: Holistic Integration for Arctic Coastal-Marine Sustainability is a new three-year research project to assess future infrastructure associated with the Arctic Ocean regarding: (1 natural and living environment; (2 built environment; (3 natural resource development; and (4 governance. For the assessments, Arctic Options will generate objective relational schema from numeric data as well as textual data. This paper will focus on the ‘long tail of smaller, heterogeneous, and often unstructured datasets’ that ‘usually receive minimal data management consideration’,as observed in the 2013 Communiqué from the International Forum on Polar Data Activities in Global Data Systems.

SEARCH: Study of Environmental Arctic Change—A System-scale, Cross-disciplinary Arctic Research Program

Science.gov (United States)

Wiggins, H. V.; Eicken, H.; Fox, S. E.

2012-12-01

SEARCH is an interdisciplinary and interagency program that works with academic and government agency scientists to plan, conduct, and synthesize studies of arctic change. The vision of SEARCH is to provide scientific understanding of arctic environmental change to help society understand and respond to a rapidly changing Arctic. Towards this end, SEARCH: 1. Generates and synthesizes research findings and promotes arctic science and scientific discovery across disciplines and among agencies. 2. Identifies emerging issues in arctic environmental change. 3. Provides information resources to arctic stakeholders, policy-makers, and the public to help them respond to arctic environmental change. 4. Coordinates with national arctic science programs integral to SEARCH goals. 5. Facilitates research activities across local-to-global scales with stakeholder concerns incorporated from the start of the planning process. 6. Represents the U.S. arctic environmental change science community in international and global change research initiatives. Specific current activities include: Arctic Observing Network (AON) - coordinating a system of atmospheric, land- and ocean-based environmental monitoring capabilities that will significantly advance our observations of arctic environmental conditions. 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. In April, the SEARCH Science Steering Committee (SSC) released a set of draft 5-year goals and objectives for review by the broader arctic science community. The goals and objectives will direct the SEARCH program in the next five years. The draft SEARCH goals focus on four areas: ice-diminished Arctic Ocean, warming

Vulnerability of Polar Oceans to Anthropogenic Acidification: Comparison of Arctic and Antarctic Seasonal Cycles

OpenAIRE

E. H. Shadwick; T. W. Trull; H. Thomas; J. A. E. Gibson

2013-01-01

Polar oceans are chemically sensitive to anthropogenic acidification due to their relatively low alkalinity and correspondingly weak carbonate buffering capacity. Here, we compare unique CO2 system observations covering complete annual cycles at an Arctic (Amundsen Gulf) and Antarctic site (Prydz Bay). The Arctic site experiences greater seasonal warming (10 vs 3?C), and freshening (3 vs 2), has lower alkalinity (2220 vs 2320??mol/kg), and lower summer pH (8.15 vs 8.5), than the Antarctic sit...

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 community...

Increased Arctic sea ice drift alters adult female polar bear movements and energetics.

Science.gov (United States)

Durner, George M; Douglas, David C; Albeke, Shannon E; Whiteman, John P; Amstrup, Steven C; Richardson, Evan; Wilson, Ryan R; Ben-David, Merav

2017-09-01

Recent reductions in thickness and extent have increased drift rates of Arctic sea ice. Increased ice drift could significantly affect the movements and the energy balance of polar bears (Ursus maritimus) which forage, nearly exclusively, on this substrate. We used radio-tracking and ice drift data to quantify the influence of increased drift on bear movements, and we modeled the consequences for energy demands of adult females in the Beaufort and Chukchi seas during two periods with different sea ice characteristics. Westward and northward drift of the sea ice used by polar bears in both regions increased between 1987-1998 and 1999-2013. To remain within their home ranges, polar bears responded to the higher westward ice drift with greater eastward movements, while their movements north in the spring and south in fall were frequently aided by ice motion. To compensate for more rapid westward ice drift in recent years, polar bears covered greater daily distances either by increasing their time spent active (7.6%-9.6%) or by increasing their travel speed (8.5%-8.9%). This increased their calculated annual energy expenditure by 1.8%-3.6% (depending on region and reproductive status), a cost that could be met by capturing an additional 1-3 seals/year. Polar bears selected similar habitats in both periods, indicating that faster drift did not alter habitat preferences. Compounding reduced foraging opportunities that result from habitat loss; changes in ice drift, and associated activity increases, likely exacerbate the physiological stress experienced by polar bears in a warming Arctic. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Depletion of stratospheric ozone over the Antarctic and Arctic: Responses of plants of polar terrestrial ecosystems to enhanced UV-B, an overview

International Nuclear Information System (INIS)

Rozema, Jelte; Boelen, Peter; Blokker, Peter

2005-01-01

Depletion of stratospheric ozone over the Antarctic has been re-occurring yearly since 1974, leading to enhanced UV-B radiation. Arctic ozone depletion has been observed since 1990. Ozone recovery has been predicted by 2050, but no signs of recovery occur. Here we review responses of polar plants to experimentally varied UV-B through supplementation or exclusion. In supplementation studies comparing ambient and above ambient UV-B, no effect on growth occurred. UV-B-induced DNA damage, as measured in polar bryophytes, is repaired overnight by photoreactivation. With UV exclusion, growth at near ambient may be less than at below ambient UV-B levels, which relates to the UV response curve of polar plants. UV-B screening foils also alter PAR, humidity, and temperature and interactions of UV with environmental factors may occur. Plant phenolics induced by solar UV-B, as in pollen, spores and lignin, may serve as a climate proxy for past UV. Since the Antarctic and Arctic terrestrial ecosystems differ essentially (e.g. higher species diversity and more trophic interactions in the Arctic), generalization of polar plant responses to UV-B needs caution. - Polar plant responses to UV-B may be different in the Arctic than Antarctic regions

PoLAR Voices: Informing Adult Learners about the Science and Story of Climate Change in the Polar Regions Through Audio Podcast

Science.gov (United States)

Quinney, A.; Murray, M. S.; Gobroski, K. A.; Topp, R. M.; Pfirman, S. L.

2015-12-01

The resurgence of audio programming with the advent of podcasting in the early 2000s spawned a new medium for communicating advances in science, research, and technology. To capitalize on this informal educational outlet, the Arctic Institute of North America partnered with the International Arctic Research Center, the University of Alaska Fairbanks, and the UA Museum of the North to develop a podcast series called PoLAR Voices for the Polar Learning and Responding (PoLAR) Climate Change Education Partnership. PoLAR Voices is a public education initiative that uses creative storytelling and novel narrative structures to immerse the listener in an auditory depiction of climate change. The programs will feature the science and story of climate change, approaching topics from both the points of view of researchers and Arctic indigenous peoples. This approach will engage the listener in the holistic story of climate change, addressing both scientific and personal perspectives, resulting in a program that is at once educational, entertaining and accessible. Feedback is being collected at each stage of development to ensure the content and format of the program satisfies listener interests and preferences. Once complete, the series will be released on thepolarhub.org and on iTunes. Additionally, blanket distribution of the programs will be accomplished via radio broadcast in urban, rural and remote areas, and in multiple languages to increase distribution and enhance accessibility.

Live from the Arctic

Science.gov (United States)

Warnick, W. K.; Haines-Stiles, G.; Warburton, J.; Sunwood, K.

2003-12-01

For reasons of geography and geophysics, the poles of our planet, the Arctic and Antarctica, are places where climate change appears first: they are global canaries in the mine shaft. But while Antarctica (its penguins and ozone hole, for example) has been relatively well-documented in recent books, TV programs and journalism, the far North has received somewhat less attention. This project builds on and advances what has been done to date to share the people, places, and stories of the North with all Americans through multiple media, over several years. In a collaborative project between the Arctic Research Consortium of the United States (ARCUS) and PASSPORT TO KNOWLEDGE, Live from the Arctic will bring the Arctic environment to the public through a series of primetime broadcasts, live and taped programming, interactive virtual field trips, and webcasts. The five-year project will culminate during the 2007-2008 International Polar Year (IPY). Live from the Arctic will: A. Promote global understanding about the value and world -wide significance of the Arctic, B. Bring cutting-edge research to both non-formal and formal education communities, C. Provide opportunities for collaboration between arctic scientists, arctic communities, and the general public. Content will focus on the following four themes. 1. Pan-Arctic Changes and Impacts on Land (i.e. snow cover; permafrost; glaciers; hydrology; species composition, distribution, and abundance; subsistence harvesting) 2. Pan-Arctic Changes and Impacts in the Sea (i.e. salinity, temperature, currents, nutrients, sea ice, marine ecosystems (including people, marine mammals and fisheries) 3. Pan-Arctic Changes and Impacts in the Atmosphere (i.e. precipitation and evaporation; effects on humans and their communities) 4. Global Perspectives (i.e. effects on humans and communities, impacts to rest of the world) In The Earth is Faster Now, a recent collection of comments by members of indigenous arctic peoples, arctic

Changes in aerobic performance, body composition, and physical activity in polar explorers during a year-long stay at the polar station in the Arctic

Science.gov (United States)

Maciejczyk, Marcin; Araźny, Andrzej; Opyrchał, Marta

2017-04-01

The aim of this study was to evaluate changes in physical activity, aerobic performance, and body composition in polar explorers during a 1-year stay at the polar station. The study group consisted of 10 people, including 8 men and 2 women. Aerobic performance (maximal oxygen uptake), physical activity, body mass, and composition were evaluated for the polar explores of the Polish Polar Station prior to departure, and then during their stay at the station for a period of 1 year. The measurements were performed every 3 months. Compared to the measurements taken before going to the polar station, aerobic performance significantly ( p = 0.02) increased in the first 3 months of residing at the polar station and then remained relatively stable for the following duration of the stay. In the first 3 months of the stay, we also observed the highest level of physical activity in participants. In the polar explorers, no significant ( p > 0.05) body fatness changes were noted. Nonetheless, lean body mass, body mass, and BMI significantly increased compared to the measurements taken before departure to the polar station. The greatest changes in aerobic performance, physical activity, and body composition were observed during the first 3 months after arrival to the Arctic and then, despite changing biometeorological conditions, they remained stable for the next months of the stay. We recommend the introduction of a physical preparation program before departing to the polar station to improve explorers' physical fitness, so that they can meet the physical challenges they are faced with immediately after arrival to the polar station.

Changing Arctic Ecosystems: Updated forecast: Reducing carbon dioxide (CO2) emissions required to improve polar bear outlook

Science.gov (United States)

Oakley, Karen L.; Atwood, Todd C.; Mugel, Douglas N.; Rode, Karyn D.; Whalen, Mary E.

2015-01-01

The Arctic is warming faster than other regions of the world due to the loss of snow and ice, which increases the amount of solar energy absorbed by the region. The most visible consequence has been the rapid decline in sea ice over the last 3 decades-a decline projected to bring long ice-free summers if greenhouse gas (GHG) emissions are not significantly reduced. The polar bear (Ursus maritimus) depends on sea ice over the biologically productive continental shelves of the Arctic Ocean as a platform for hunting seals. In 2008, the U.S. Fish and Wildlife Service listed the polar bear as threatened under the Endangered Species Act (ESA) due to the threat posed by sea ice loss. The polar bear was the first species to be listed due to forecasted population declines from climate change.

Influence of Arctic Sea Ice Extent on Polar Cloud Fraction and Vertical Structure and Implications for Regional Climate

Science.gov (United States)

Palm, Stephen P.; Strey, Sara T.; Spinhirne, James; Markus, Thorsten

2010-01-01

Recent satellite lidar measurements of cloud properties spanning a period of 5 years are used to examine a possible connection between Arctic sea ice amount and polar cloud fraction and vertical distribution. We find an anticorrelation between sea ice extent and cloud fraction with maximum cloudiness occurring over areas with little or no sea ice. We also find that over ice!free regions, there is greater low cloud frequency and average optical depth. Most of the optical depth increase is due to the presence of geometrically thicker clouds over water. In addition, our analysis indicates that over the last 5 years, October and March average polar cloud fraction has increased by about 7% and 10%, respectively, as year average sea ice extent has decreased by 5% 7%. The observed cloud changes are likely due to a number of effects including, but not limited to, the observed decrease in sea ice extent and thickness. Increasing cloud amount and changes in vertical distribution and optical properties have the potential to affect the radiative balance of the Arctic region by decreasing both the upwelling terrestrial longwave radiation and the downward shortwave solar radiation. Because longwave radiation dominates in the long polar winter, the overall effect of increasing low cloud cover is likely a warming of the Arctic and thus a positive climate feedback, possibly accelerating the melting of Arctic sea ice.

Arctic Forecasts Available from Polar Bear Exhibit as an Example of Formal/Informal Collaboration

Science.gov (United States)

Landis, C. E.; Cervenec, J.

2012-12-01

A subset of the general population enjoys and frequents informal education venues, offering an opportunity for lifelong learning that also enhances and supports formal education efforts. The Byrd Polar Research Center (BPRC) at The Ohio State University collaborated with the Columbus Zoo & Aquarium (CZA) in the development of their Polar Frontier exhibit, from its initial planning to the Grand Opening of the exhibit, through the present. Of course, the addition to the Zoo of polar bears and Arctic fox in the Polar Frontier has been very popular, with almost a 7% increase in visitors in 2010 when the exhibit opened. The CZA and BPRC are now investigating ways to increase the climate literacy impact of the exhibit, and to increase engagement with the topics through follow-on activities. For example, individuals or classes anywhere in the world can check forecasts from the Polar Weather and Research Forecasting model and compare them to observed conditions-- allowing deep investigation into changes in the Arctic. In addition, opportunities exist to adapt the Zoo School experience (affecting several Central Ohio school districts) and/or to enable regular participation through social media such as Facebook, Twitter, and other forms of digital communication. BPRC's sustained engagement with the CZA is an example of a trusted and meaningful partnership where open dialogue exists about providing the best learning experience for visitors. This presentation will share some of the lessons learned from this unique partnership, and strategies that are adopted to move it forward.

Integrating Access to Arctic Environmental Change and Human Health Research for the International Polar Year and Beyond

Science.gov (United States)

Garrett, C. L.

2006-12-01

hosting the Arctic Human Health Initiative (AHHI), the human health focus of the International Polar Year activities. AHHI will coordinate research in the areas of infectious disease; the effects of anthropogenic pollution, UV radiation, and climate variability on human health; and telehealth innovations. A major goal of AHHI is the better integration of the findings of Arctic health research through outreach programs and public education.

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

Chemical ozone losses in Arctic and Antarctic polar winter/spring season derived from SCIAMACHY limb measurements 2002–2009

Directory of Open Access Journals (Sweden)

T. Sonkaew

2013-02-01

Full Text Available Stratospheric ozone profiles are retrieved for the period 2002–2009 from SCIAMACHY measurements of limb-scattered solar radiation in the Hartley and Chappuis absorption bands of ozone. This data set is used to determine the chemical ozone losses in both the Arctic and Antarctic polar vortices by averaging the ozone in the vortex at a given potential temperature. The chemical ozone losses at isentropic levels between 450 K and 600 K are derived from the difference between observed ozone abundances and the ozone modelled taking diabatic cooling into account, but no chemical ozone loss. Chemical ozone losses of up to 30–40% between mid-January and the end of March inside the Arctic polar vortex are reported. Strong inter-annual variability of the Arctic ozone loss is observed, with the cold winters 2004/2005 and 2006/2007 showing chemical ozone losses inside the polar vortex at 475 K, where 1.7 ppmv and 1.4 ppmv of ozone were removed, respectively, over the period from 22 January to beginning of April and 0.9 ppmv and 1.2 ppmv, respectively, during February. For the winters of 2007/2008 and 2002/2003, ozone losses of about 0.8 ppmv and 0.4 ppmv, respectively are estimated at the 475 K isentropic level for the period from 22 January to beginning of April. Essentially no ozone losses were diagnosed for the relatively warm winters of 2003/2004 and 2005/2006. The maximum ozone loss in the SCIAMACHY data set was found in 2007 at the 600 K level and amounted to about 2.1 ppmv for the period between 22 January and the end of April. Enhanced losses close to this altitude were found in all investigated Arctic springs, in contrast to Antarctic spring. The inter-annual variability of ozone losses and PSC occurrence rates observed during Arctic spring is consistent with the known QBO effects on the Arctic polar vortex, with exception of the unusual Arctic winter 2008/2009.

The maximum total ozone mass loss of about 25 million tons was found in the

Polar solar panels: Arctic and Antarctic microbiomes display similar taxonomic profiles.

Science.gov (United States)

Tanner, Kristie; Martí, Jose Manuel; Belliure, Josabel; Fernández-Méndez, Mar; Molina-Menor, Esther; Peretó, Juli; Porcar, Manuel

2018-02-01

Solar panels located on high (Arctic and Antarctic) latitudes combine the harshness of the climate with that of the solar exposure. We report here that these polar solar panels are inhabited by similar microbial communities in taxonomic terms, dominated by Hymenobacter spp., Sphingomonas spp. and Ascomycota. Our results suggest that solar panels, even on high latitudes, can shape a microbial ecosystem adapted to irradiation and desiccation. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

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...

The Influence of Arctic Sea Ice Extent on Polar Cloud Fraction and Vertical Structure and Implications for Regional Climate

Science.gov (United States)

Palm, Stephen P.; Strey, Sara T.; Spinhirne, James; Markus, Thorsten

2010-01-01

Recent satellite lidar measurements of cloud properties spanning a period of five years are used to examine a possible connection between Arctic sea ice amount and polar cloud fraction and vertical distribution. We find an anti-correlation between sea ice extent and cloud fraction with maximum cloudiness occurring over areas with little or no sea ice. We also find that over ice free regions, there is greater low cloud frequency and average optical depth. Most of the optical depth increase is due to the presence of geometrically thicker clouds over water. In addition, our analysis indicates that over the last 5 years, October and March average polar cloud fraction has increased by about 7 and 10 percent, respectively, as year average sea ice extent has decreased by 5 to 7 percent. The observed cloud changes are likely due to a number of effects including, but not limited to, the observed decrease in sea ice extent and thickness. Increasing cloud amount and changes in vertical distribution and optical properties have the potential to affect the radiative balance of the Arctic region by decreasing both the upwelling terrestrial longwave radiation and the downward shortwave solar radiation. Since longwave radiation dominates in the long polar winter, the overall effect of increasing low cloud cover is likely a warming of the Arctic and thus a positive climate feedback, possibly accelerating the melting of Arctic sea ice.

A closer look at Arctic ozone loss and polar stratospheric clouds

Directory of Open Access Journals (Sweden)

N. R. P. Harris

2010-09-01

Full Text Available The empirical relationship found between column-integrated Arctic ozone loss and the potential volume of polar stratospheric clouds inferred from meteorological analyses is recalculated in a self-consistent manner using the ERA Interim reanalyses. The relationship is found to hold at different altitudes as well as in the column. The use of a PSC formation threshold based on temperature dependent cold aerosol formation makes little difference to the original, empirical relationship. Analysis of the photochemistry leading to the ozone loss shows that activation is limited by the photolysis of nitric acid. This step produces nitrogen dioxide which is converted to chlorine nitrate which in turn reacts with hydrogen chloride on any polar stratospheric clouds to form active chlorine. The rate-limiting step is the photolysis of nitric acid: this occurs at the same rate every year and so the interannual variation in the ozone loss is caused by the extent and persistence of the polar stratospheric clouds. In early spring the ozone loss rate increases as the solar insolation increases the photolysis of the chlorine monoxide dimer in the near ultraviolet. However the length of the ozone loss period is determined by the photolysis of nitric acid which also occurs in the near ultraviolet. As a result of these compensating effects, the amount of the ozone loss is principally limited by the extent of original activation rather than its timing. In addition a number of factors, including the vertical changes in pressure and total inorganic chlorine as well as denitrification and renitrification, offset each other. As a result the extent of original activation is the most important factor influencing ozone loss. These results indicate that relatively simple parameterisations of Arctic ozone loss could be developed for use in coupled chemistry climate models.

Promoting Diversity Through Polar Interdisciplinary Coordinated Education (Polar ICE)

Science.gov (United States)

McDonnell, J. D.; Hotaling, L. A.; Garza, C.; Van Dyk, P. B.; Hunter-thomson, K. I.; Middendorf, J.; Daniel, A.; Matsumoto, G. I.; Schofield, O.

2017-12-01

Polar Interdisciplinary Coordinated Education (ICE) is an education and outreach program designed to provide public access to the Antarctic and Arctic regions through polar data and interactions with the scientists. The program provides multi-faceted science communication training for early career scientists that consist of a face-to face workshop and opportunities to apply these skills. The key components of the scientist training workshop include cultural competency training, deconstructing/decoding science for non-expert audiences, the art of telling science stories, and networking with members of the education and outreach community and reflecting on communication skills. Scientists partner with educators to provide professional development for K-12 educators and support for student research symposia. Polar ICE has initiated a Polar Literacy initiative that provides both a grounding in big ideas in polar science and science communication training designed to underscore the importance of the Polar Regions to the public while promoting interdisciplinary collaborations between scientists and educators. Our ultimate objective is to promote STEM identity through professional development of scientists and educators while developing career awareness of STEM pathways in Polar science.

Correlations of mesospheric winds with subtle motion of the Arctic polar vortex

Directory of Open Access Journals (Sweden)

Y. Bhattacharya

2010-01-01

Full Text Available This paper investigates the relationship between high latitude upper mesospheric winds and the state of the stratospheric polar vortex in the absence of major sudden stratospheric warmings. A ground based Michelson Interferometer stationed at Resolute Bay (74°43' N, 94°58' W in the Canadian High Arctic is used to measure mesopause region neutral winds using the hydroxyl (OH Meinel-band airglow emission (central altitude of ~85 km. These observed winds are compared to analysis winds in the upper stratosphere during November and December of 1995 and 1996; years characterized as cold, stable polar vortex periods. Correlation of mesopause wind speeds with those from the upper stratosphere is found to be significant for the 1996 season when the polar vortex is subtly displaced off its initial location by a strong Aleutian High. These mesopause winds are observed to lead stratospheric winds by approximately two days with increasing (decreasing mesospheric winds predictive of decreasing (increasing stratospheric winds. No statistically significant correlations are found for the 1995 season when there is no such displacement of the polar vortex.

Enabling Arctic Research Through Science and Engineering Partnerships

Science.gov (United States)

Kendall, E. A.; Valentic, T. A.; Stehle, R. H.

2014-12-01

Under an Arctic Research Support and Logistics contract from NSF (GEO/PLR), SRI International, as part of the CH2M HILL Polar Services (CPS) program, forms partnerships with Arctic research teams to provide data transfer, remote operations, and safety/operations communications. This teamwork is integral to the success of real-time science results and often allows for unmanned operations which are both cost-effective and safer. The CPS program utilizes a variety of communications networks, services and technologies to support researchers and instruments throughout the Arctic, including Iridium, VSAT, Inmarsat BGAN, HughesNet, TeleGreenland, radios, and personal locator beacons. Program-wide IT and communications limitations are due to the broad categories of bandwidth, availability, and power. At these sites it is essential to conserve bandwidth and power through using efficient software, coding and scheduling techniques. There are interesting new products and services on the horizon that the program may be able to take advantage of in the future such as Iridium NEXT, Inmarsat Xpress, and Omnispace mobile satellite services. Additionally, there are engineering and computer software opportunities to develop more efficient products. We will present an overview of science/engineering partnerships formed by the CPS program, discuss current limitations and identify future technological possibilities that could further advance Arctic science goals.

Using satellite telemetry to define spatial population structure in polar bears in the Norwegian and western Russian Arctic

Science.gov (United States)

Mauritzen, Mette; Derocher, Andrew E.; Wiig, Øystein; Belikov, Stanislav; Boltunov, Andrei N.; Garner, Gerald W.

2002-01-01

1. Animal populations, defined by geographical areas within a species’ distribution where population dynamics are largely regulated by births and deaths rather than by migration from surrounding areas, may be the correct unit for wildlife management. However, in heterogeneous landscapes varying habitat quality may yield subpopulations with distinct patterns in resource use and demography significant to the dynamics of populations.2. To define the spatial population structure of polar bears Ursus maritimus in the Norwegian and western Russian Arctic, and to assess the existence of a shared population between the two countries, we analysed satellite telemetry data obtained from 105 female polar bears over 12 years.3. Using both cluster analyses and home-range estimation methods, we identified five population units inhabiting areas with different sea-ice characteristics and prey availability.4. The continuous distribution of polar bear positions indicated that the different subpopulations formed one continuous polar bear population in the Norwegian and western Russian Arctic. Hence, Norway and Russia have a shared management responsibility.5. The spatial population structure identified will provide a guide for evaluating geographical patterns in polar bear ecology, the dynamics of polar bear–seal relationships and the effects of habitat alteration due to climate change. The work illustrates the importance of defining population borders and subpopulation structure in understanding the dynamics and management of larger animals.

Arctic research vessel design would expand science prospects

Science.gov (United States)

Elsner, Robert; Kristensen, Dirk

The U.S. polar marine science community has long declared the need for an arctic research vessel dedicated to advancing the study of northern ice-dominated seas. Planning for such a vessel began 2 decades ago, but competition for funding has prevented construction. A new design program is underway, and it shows promise of opening up exciting possibilities for new research initiatives in arctic marine science.With its latest design, the Arctic Research Vessel (ARV) has grown to a size and capability that will make it the first U.S. academic research vessel able to provide access to the Arctic Ocean. This ship would open a vast arena for new studies in the least known of the world's seas. These studies promise to rank high in national priority because of the importance of the Arctic Ocean as a source of data relating to global climate change. Other issues that demand attention in the Arctic include its contributions to the world's heat budget, the climate history buried in its sediments, pollution monitoring, and the influence of arctic conditions on marine renewable resources.

Identifying polar bear resource selection patterns to inform offshore development in a dynamic and changing Arctic

Science.gov (United States)

Wilson, Ryan R.; Horne, Jon S.; Rode, Karyn D.; Regehr, Eric V.; Durner, George M.

2014-01-01

Although sea ice loss is the primary threat to polar bears (Ursus maritimus), little can be done to mitigate its effects without global efforts to reduce greenhouse gas emissions. Other factors, however, could exacerbate the impacts of sea ice loss on polar bears, such as exposure to increased industrial activity. The Arctic Ocean has enormous oil and gas potential, and its development is expected to increase in the coming decades. Estimates of polar bear resource selection will inform managers how bears use areas slated for oil development and to help guide conservation planning. We estimated temporally-varying resource selection patterns for non-denning adult female polar bears in the Chukchi Sea population (2008–2012) at two scales (i.e., home range and weekly steps) to identify factors predictive of polar bear use throughout the year, before any offshore development. From the best models at each scale, we estimated scale-integrated resource selection functions to predict polar bear space use across the population's range and determined when bears were most likely to use the region where offshore oil and gas development in the United States is slated to occur. Polar bears exhibited significant intra-annual variation in selection patterns at both scales but the strength and annual patterns of selection differed between scales for most variables. Bears were most likely to use the offshore oil and gas planning area during ice retreat and growth with the highest predicted use occurring in the southern portion of the planning area. The average proportion of predicted high-value habitat in the planning area was >15% of the total high-value habitat for the population during sea ice retreat and growth and reached a high of 50% during November 2010. Our results provide a baseline on which to judge future changes to non-denning adult female polar bear resource selection in the Chukchi Sea and help guide offshore development in the region. Lastly, our study provides a

PolarTREC-Teachers and Researchers Exploring and Collaborating: Innovative Science Education from the Poles to the World

Science.gov (United States)

Warnick, W. K.; Warburton, J.; Breen, K.; Wiggins, H. V.; Larson, A.; Behr, S.

2006-12-01

PolarTREC-Teachers and Researchers Exploring and Collaborating is a three-year (2007-2009) teacher professional development program celebrating the International Polar Year (IPY) that will advance polar science education by bringing K-12 educators and polar researchers together in hands-on field experiences in the Arctic and Antarctic. PolarTREC builds on the strengths of the existing TREC program in the Arctic, an NSF supported program managed by the Arctic Research Consortium of the US (ARCUS), to embrace a wide range of activities occurring at both poles during and after IPY. PolarTREC will foster the integration of research and education to produce a legacy of long-term teacher-researcher collaborations, improved teacher content knowledge through experiences in scientific inquiry, and broad public interest and engagement in polar science and IPY. PolarTREC will enable thirty-six teachers to spend two to six weeks in the Arctic or Antarctic, working closely with researchers investigating a wide range of IPY science themed topics such as sea-ice dynamics, terrestrial ecology, marine biology, atmospheric chemistry, and long-term climate change. While in the field, teachers and researchers will communicate extensively with their colleagues, communities, and hundreds of students of all ages across the globe, using a variety of tools including satellite phones, online journals, podcasts and interactive "Live from IPY" calls and web-based seminars. The online outreach elements of the project convey these experiences to a broad audience far beyond the classrooms of the PolarTREC teachers. In addition to field research experiences, PolarTREC will support teacher professional development and a sustained community of teachers, scientists, and the public through workshops, Internet seminars, an e-mail listserve, and teacher peer groups. For further information on PolarTREC, contact Wendy Warnick, ARCUS Executive Director at warnick@arcus.org or 907-474-1600 or visit www.arcus.org/trec/

Connecting Arctic Research Across Boundaries through the Arctic Research Consortium of the United States (ARCUS)

Science.gov (United States)

Rich, R. H.; Myers, B.; Wiggins, H. V.; Zolkos, J.

2017-12-01

The complexities inherent in Arctic research demand a unique focus on making connections across the boundaries of discipline, institution, sector, geography, knowledge system, and culture. Since 1988, ARCUS has been working to bridge these gaps through communication, coordination, and collaboration. Recently, we have worked with partners to create a synthesis of the Arctic system, to explore the connectivity across the Arctic research community and how to strengthen it, to enable the community to have an effective voice in research funding policy, to implement a system for Arctic research community knowledge management, to bridge between global Sea Ice Prediction Network researchers and the science needs of coastal Alaska communities through the Sea Ice for Walrus Outlook, to strengthen ties between Polar researchers and educators, and to provide essential intangible infrastructure that enables cost-effective and productive research across boundaries. Employing expertise in managing for collaboration and interdisciplinarity, ARCUS complements and enables the work of its members, who constitute the Arctic research community and its key stakeholders. As a member-driven organization, everything that ARCUS does is achieved through partnership, with strong volunteer leadership of each activity. Key organizational partners in the United States include the U.S. Arctic Research Commission, Interagency Arctic Research Policy Committee, National Academy of Sciences Polar Research Board, and the North Slope Science Initiative. Internationally, ARCUS maintains strong bilateral connections with similarly focused groups in each Arctic country (and those interested in the Arctic), as well as with multinational organizations including the International Arctic Science Committee, the Association of Polar Early Career Educators, the University of the Arctic, and the Arctic Institute of North America. Currently, ARCUS is applying the best practices of the science of team science

Arctic Observing Experiment (AOX) Field Campaign Report

Energy Technology Data Exchange (ETDEWEB)

Rigor, Ignatius [Applied Physics Lab, University of Washington; Johnson, Jim [Applied Physics Lab, University of Washington; Motz, Emily [National Ice Center; Bisic, Aaron [National Ice Center

2017-06-30

Our ability to understand and predict weather and climate requires an accurate observing network. One of the pillars of this network is the observation of the fundamental meteorological parameters: temperature, air pressure, and wind. We plan to assess our ability to measure these parameters for the polar regions during the Arctic Observing Experiment (AOX, Figure 1) to support the International Arctic Buoy Programme (IABP), Arctic Observing Network (AON), International Program for Antarctic Buoys (IPAB), and Southern Ocean Observing System (SOOS). Accurate temperature measurements are also necessary to validate and improve satellite measurements of surface temperature across the Arctic. Support for research associated with the campaign is provided by the National Science Foundation, and by other US agencies contributing to the US Interagency Arctic Buoy Program. In addition to the support provided by the U.S Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s North Slope of Alaska (NSA) site at Barrow and the National Science Foundation (NSF), the U.S. IABP is supported by the U.S. Coast Guard (USCG), the National Aeronautics and Space Administration (NASA), the National Ice Center (NIC), the National Oceanic and Atmospheric Administration (NOAA), and the Office of Naval Research (ONR).

The Arctic - A New Region for China's Foreign Policy

Directory of Open Access Journals (Sweden)

V S Yagiya

2015-12-01

Full Text Available Article is devoted to foreign policy of China in the Arctic. Main attention is paid to strategic view of the China concerning the Arctic, to bilateral and multilateral cooperation on the Arctic issues, also to opinion of Russian experts about discussing of Russian-China economic partnership. It was shown interests of the People's Republic of China in the Arctic: use Arctic transport system from the Pacific Rim to Europe; possibility of access to the Arctic resources; seeks of partners for the realized of Arctic projects and programs. It was pointed six directions of China cooperation in the Arctic: a scientific researches, b natural minerals, oil and gas issues, c tourism, d routes of the Arctic navigation, e use of high technologies in development of regional economy, e cooperation in the cultural and educational spheres. Authors are summarized that at the initial stage of the international cooperation in the Arctic polar scientific researches become as the tool of “he soft power”, and in the long term - the Northern Sea Route of the Russian Federation is included in the Strategy of China Economic belt and the Maritime Silk Route in the XXI century.

Potential for an Arctic-breeding migratory bird to adjust spring migration phenology to Arctic amplification

NARCIS (Netherlands)

Lameris, T.K.; Scholten, Ilse; Bauer, S.; Cobben, M.M.P.; Ens, B.J.; Nolet, B.A.

2017-01-01

Arctic amplification, the accelerated climate warming in the polar regions, is causing a more rapid advancement of the onset of spring in the Arctic than in temperate regions. Consequently, the arrival of many migratory birds in the Arctic is thought to become increasingly mismatched with the onset

Application of Terrestrial Ecosystem Monitoring under the CAFF Circumpolar Biodiversity Monitoring Program: Designing and Implementing Terrestrial Monitoring to Establish the Canadian High Arctic Research Station as a Flagship Arctic Environmental Monitoring Site

Science.gov (United States)

McLennan, D.; Kehler, D.

2016-12-01

The Canadian High Arctic Research Station (CHARS) is scheduled for completion in July 2017 and is the northern science component of Polar Knowledge Canada (POLAR). A mandated goal for POLAR is to establish the adjacent Experimental and Reference Area (ERA) as an Arctic Flagship monitoring site that will track change in Arctic terrestrial, freshwater and marine ecosystems. Situated in the community of Cambridge Bay, CHARS provides the opportunity to draw on the Indigenous Knowledge of local residents to help design and conduct the monitoring, and to operate 12 months a year. Monitoring at CHARS will be linked to networks nationally and internationally, and is being designed so that change in key indicators can be understood in terms of drivers and processes, modeled and scaled up regionally, and used to predict important changes in critical indicators. As a partner in the Circumpolar Biodiversity Monitoring Program (CBMP), the monitoring design for terrestrial ecosystems follows approaches outlined by the CBMP Terrestrial Expert Monitoring Group, who have listed key monitoring questions and identified a list of important Focal Ecosystem Components (FECs). To link drivers to FECs we are proposing a multi-scaled approach: 1) an Intensive Monitoring Area to establish replicated monitoring plots that track change in snow depth and condition, active layer depth, soil temperature, soil moisture, and soil solution chemistry that are spatially and temporally linked to changes in microbiological activity, CO2/CH4 net ecosystem flux, vegetation relative frequency, species composition, growth and foliar nutrient concentration, arthropod abundance, lemming abundance and health, and shorebird/songbird abundance and productivity. 2) These intensive observations are supported by watershed scale measures that will monitor, during the growing season, lemming winter nest abundance, songbird, shorebird and waterfowl staging and nesting, and other observations; in the winter we will

The Arctic Human Health Initiative: a legacy of the International Polar Year 2007-2009.

Science.gov (United States)

Parkinson, Alan J

2013-01-01

The International Polar Year (IPY) 2007-2008 represented a unique opportunity to further stimulate cooperation and coordination on Arctic health research and increase the awareness and visibility of Arctic regions. The Arctic Human Health Initiative (AHHI) was a US-led Arctic Council IPY coordinating project that aimed to build and expand on existing International Union for Circumpolar Health (IUCH) and Arctic Council human health interests. The project aimed to link researchers with potential international collaborators and to serve as a focal point for human health research, education, outreach and communication activities during the IPY. The progress of projects conducted as part of this initiative up until the end of the Arctic Council Swedish chairmanship in May 2013 is summarized in this report. The overall goals of the AHHI was to increase awareness and visibility of human health concerns of Arctic peoples, foster human health research, and promote health strategies that will improve health and well-being of all Arctic residents. Proposed activities to be recognized through the initiative included: expanding research networks that will enhance surveillance and monitoring of health issues of concern to Arctic peoples, and increase collaboration and coordination of human health research; fostering research that will examine the health impact of anthropogenic pollution, rapid modernization and economic development, climate variability, infectious and chronic diseases, intentional and unintentional injuries, promoting education, outreach and communication that will focus public and political attention on Arctic health issues, using a variety of publications, printed and electronic reports from scientific conferences, symposia and workshops targeting researchers, students, communities and policy makers; promoting the translation of research into health policy and community action including implementation of prevention strategies and health promotion; and

Differences in mercury bioaccumulation between polar bears (Ursus maritimus) from the Canadian high- and sub-Arctic.

Science.gov (United States)

St Louis, Vincent L; Derocher, Andrew E; Stirling, Ian; Graydon, Jennifer A; Lee, Caroline; Jocksch, Erin; Richardson, Evan; Ghorpade, Sarah; Kwan, Alvin K; Kirk, Jane L; Lehnherr, Igor; Swanson, Heidi K

2011-07-15

Polar bears (Ursus maritimus) are being impacted by climate change and increased exposure to pollutants throughout their northern circumpolar range. In this study, we quantified concentrations of total mercury (THg) in the hair of polar bears from Canadian high- (southern Beaufort Sea, SBS) and sub- (western Hudson Bay, WHB) Arctic populations. Concentrations of THg in polar bears from the SBS population (14.8 ± 6.6 μg g(-1)) were significantly higher than in polar bears from WHB (4.1 ± 1.0 μg g(-1)). On the basis of δ(15)N signatures in hair, in conjunction with published δ(15)N signatures in particulate organic matter and sediments, we estimated that the pelagic and benthic food webs in the SBS are ∼ 4.7 and ∼ 4.0 trophic levels long, whereas in WHB they are only ∼ 3.6 and ∼ 3.3 trophic levels long. Furthermore, the more depleted δ(13)C ratios in hair from SBS polar bears relative to those from WHB suggests that SBS polar bears feed on food webs that are relatively more pelagic (and longer), whereas polar bears from WHB feed on those that are relatively more benthic (and shorter). Food web length and structure accounted for ∼ 67% of the variation we found in THg concentrations among all polar bears across both populations. The regional difference in polar bear hair THg concentrations was also likely due to regional differences in water-column concentrations of methyl Hg (the toxic form of Hg that biomagnifies through food webs) available for bioaccumulation at the base of the food webs. For example, concentrations of methylated Hg at mid-depths in the marine water column of the northern Canadian Arctic Archipelago were 79.8 ± 37.3 pg L(-1), whereas, in HB, they averaged only 38.3 ± 16.6 pg L(-1). We conclude that a longer food web and higher pelagic concentrations of methylated Hg available to initiate bioaccumulation in the BS resulted in higher concentrations of THg in polar bears from the SBS region compared to those inhabiting the western

Polar bears from space: Assessing satellite imagery as a tool to track Arctic wildlife

Science.gov (United States)

Stapleton, Seth P.; LaRue, Michelle A.; Lecomte, Nicolas; Atkinson, Stephen N.; Garshelis, David L.; Porter, Claire; Atwood, Todd C.

2014-01-01

Development of efficient techniques for monitoring wildlife is a priority in the Arctic, where the impacts of climate change are acute and remoteness and logistical constraints hinder access. We evaluated high resolution satellite imagery as a tool to track the distribution and abundance of polar bears. We examined satellite images of a small island in Foxe Basin, Canada, occupied by a high density of bears during the summer ice-free season. Bears were distinguished from other light-colored spots by comparing images collected on different dates. A sample of ground-truthed points demonstrated that we accurately classified bears. Independent observers reviewed images and a population estimate was obtained using mark- recapture models. This estimate (N: 94; 95% Confidence Interval: 92-105) was remarkably similar to an abundance estimate derived from a line transect aerial survey conducted a few days earlier (N: 102; 95% CI: 69-152). Our findings suggest that satellite imagery is a promising tool for monitoring polar bears on land, with implications for use with other Arctic wildlife. Large scale applications may require development of automated detection processes to expedite review and analysis. Future research should assess the utility of multi-spectral imagery and examine sites with different environmental characteristics.

Polar bears from space: assessing satellite imagery as a tool to track Arctic wildlife.

Directory of Open Access Journals (Sweden)

Seth Stapleton

Full Text Available Development of efficient techniques for monitoring wildlife is a priority in the Arctic, where the impacts of climate change are acute and remoteness and logistical constraints hinder access. We evaluated high resolution satellite imagery as a tool to track the distribution and abundance of polar bears. We examined satellite images of a small island in Foxe Basin, Canada, occupied by a high density of bears during the summer ice-free season. Bears were distinguished from other light-colored spots by comparing images collected on different dates. A sample of ground-truthed points demonstrated that we accurately classified bears. Independent observers reviewed images and a population estimate was obtained using mark-recapture models. This estimate (N: 94; 95% Confidence Interval: 92-105 was remarkably similar to an abundance estimate derived from a line transect aerial survey conducted a few days earlier (N: 102; 95% CI: 69-152. Our findings suggest that satellite imagery is a promising tool for monitoring polar bears on land, with implications for use with other Arctic wildlife. Large scale applications may require development of automated detection processes to expedite review and analysis. Future research should assess the utility of multi-spectral imagery and examine sites with different environmental characteristics.

Polar bears from space: assessing satellite imagery as a tool to track Arctic wildlife.

Science.gov (United States)

Stapleton, Seth; LaRue, Michelle; Lecomte, Nicolas; Atkinson, Stephen; Garshelis, David; Porter, Claire; Atwood, Todd

2014-01-01

Development of efficient techniques for monitoring wildlife is a priority in the Arctic, where the impacts of climate change are acute and remoteness and logistical constraints hinder access. We evaluated high resolution satellite imagery as a tool to track the distribution and abundance of polar bears. We examined satellite images of a small island in Foxe Basin, Canada, occupied by a high density of bears during the summer ice-free season. Bears were distinguished from other light-colored spots by comparing images collected on different dates. A sample of ground-truthed points demonstrated that we accurately classified bears. Independent observers reviewed images and a population estimate was obtained using mark-recapture models. This estimate (N: 94; 95% Confidence Interval: 92-105) was remarkably similar to an abundance estimate derived from a line transect aerial survey conducted a few days earlier (N: 102; 95% CI: 69-152). Our findings suggest that satellite imagery is a promising tool for monitoring polar bears on land, with implications for use with other Arctic wildlife. Large scale applications may require development of automated detection processes to expedite review and analysis. Future research should assess the utility of multi-spectral imagery and examine sites with different environmental characteristics.

Biological Environmental Arctic Project (BEAP) Preliminary Data (Arctic West Summer 1986 Cruise).

Science.gov (United States)

1986-11-01

predictive model of bioluminescence in near-surface arctic waters . Data were collected during Arctic West Summer 1986 from USCG POLAR STAR (WAGB 10). . %. J...2 20ODISTRIBUTION AVAILABILIT "Y OF ABSTRACT 21 ABSTRACT SECURITY CLASSIFICATION C]UNCLASSIFIED UNLIMITED SAME AS RPT C] DTIC USERS UNCLASSIFIED David...correlates for a predictive model of bioluminescence in near-surface arctic waters . - In previous years, these measurements were conducted from the USCG

AMOP (Arctic Marine Oil Spill Program) studies reviewed

Energy Technology Data Exchange (ETDEWEB)

1978-06-05

A discussion of the Arctic Marine Oil Spill Program organized in 1976 by the Canadian Federal Government includes: an Arctic Atlas compiled by Fenco Consultants Ltd. to give background information necessary for developing marine oil spill countermeasures for the Arctic north of 60/sup 0/ including the west Greenland coast and the Labrador shelf (geology, meteorology and oceanography, ice conditions, biology, and social factors); program in emergency transport of spill-combatting equipment; and the factors which influence the choice of conveyance, i.e., accessibility of the site, urgency for response, and quantity of material required; laboratory studies involving the release of oil under artificial sea ice in simulated ice formation and decay purposes to determine the interaction of crude oil and first-year sea ice; inability of companies and government to control a major spill in the Labrador Sea because of poor and inadequate transport facilities, communications, and navigational aids, severe environmental conditions, and logistics problems; and studies on the effects of oil-well blowouts in deep water, including formation of oil and gas hydrates, design of oil skimmers, the use of hovercraft, and specifications for an airborne multisensor system for oil detection in ice-infested waters.

Arctic security in an age of climate change

Energy Technology Data Exchange (ETDEWEB)

Kraska, James (ed.)

2013-03-01

Publisher review: This book examines Arctic defense policy and military security from the perspective of all eight Arctic states. In light of climate change and melting ice in the Arctic Ocean, Canada, Russia, Denmark (Greenland), Norway and the United States, as well as Iceland, Sweden and Finland, are grappling with an emerging Arctic security paradigm. This volume brings together the world's most seasoned Arctic political-military experts from Europe and North America to analyze how Arctic nations are adapting their security postures to accommodate increased shipping, expanding naval presence, and energy and mineral development in the polar region. The book analyzes the ascent of Russia as the first 'Arctic superpower', the growing importance of polar security for NATO and the Nordic states, and the increasing role of Canada and the United States in the region.(Author)

AROME-Arctic: New operational NWP model for the Arctic region

Science.gov (United States)

Süld, Jakob; Dale, Knut S.; Myrland, Espen; Batrak, Yurii; Homleid, Mariken; Valkonen, Teresa; Seierstad, Ivar A.; Randriamampianina, Roger

2016-04-01

In the frame of the EU-funded project ACCESS (Arctic Climate Change, Economy and Society), MET Norway aimed 1) to describe the present monitoring and forecasting capabilities in the Arctic; and 2) to identify the key factors limiting the forecasting capabilities and to give recommendations on key areas to improve the forecasting capabilities in the Arctic. We have observed that the NWP forecast quality is lower in the Arctic than in the regions further south. Earlier research indicated that one of the factors behind this is the composition of the observing system in the Arctic, in particular the scarceness of conventional observations. To further assess possible strategies for alleviating the situation and propose scenarios for a future Arctic observing system, we have performed a set of experiments to gain a more detailed insight in the contribution of the components of the present observing system in a regional state-of-the-art non-hydrostatic NWP model using the AROME physics (Seity et al, 2011) at 2.5 km horizontal resolution - AROME-Arctic. Our observing system experiment studies showed that conventional observations (Synop, Buoys) can play an important role in correcting the surface state of the model, but prove that the present upper-air conventional (Radiosondes, Aircraft) observations in the area are too scarce to have a significant effect on forecasts. We demonstrate that satellite sounding data play an important role in improving forecast quality. This is the case with satellite temperature sounding data (AMSU-A, IASI), as well as with the satellite moisture sounding data (AMSU-B/MHS, IASI). With these sets of observations, the AROME-Arctic clearly performs better in forecasting extreme events, like for example polar lows. For more details see presentation by Randriamampianina et al. in this session. The encouraging performance of AROME-Arctic lead us to implement it with more observations and improved settings into daily runs with the objective to

Environmental marine geology of the Arctic Ocean

International Nuclear Information System (INIS)

Mudie, P.J.

1991-01-01

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

Atmospheric transport of pollution to the Arctic

International Nuclear Information System (INIS)

Iversen, T.

1984-01-01

If the atmospheric processes are assumed to be nearly adiabatic, the conclusion is that the possible source areas of Arctic air pollution detected at ground level have to be situated in areas with almost the same temperature as observed in the Arctic itself. Sources south of the polar front system can only contribute to high-altitude (or upper level) Arctic pollution. The amplitude and phase of long, planetary waves are important since they determine the position of the polar front, and provide conditions for meridional transport of air at certain longitudes

High Arctic summer warming tracked by increased Cassiope tetragona growth in the world's northernmost polar desert.

Science.gov (United States)

Weijers, Stef; Buchwal, Agata; Blok, Daan; Löffler, Jörg; Elberling, Bo

2017-11-01

Rapid climate warming has resulted in shrub expansion, mainly of erect deciduous shrubs in the Low Arctic, but the more extreme, sparsely vegetated, cold and dry High Arctic is generally considered to remain resistant to such shrub expansion in the next decades. Dwarf shrub dendrochronology may reveal climatological causes of past changes in growth, but is hindered at many High Arctic sites by short and fragmented instrumental climate records. Moreover, only few High Arctic shrub chronologies cover the recent decade of substantial warming. This study investigated the climatic causes of growth variability of the evergreen dwarf shrub Cassiope tetragona between 1927 and 2012 in the northernmost polar desert at 83°N in North Greenland. We analysed climate-growth relationships over the period with available instrumental data (1950-2012) between a 102-year-long C. tetragona shoot length chronology and instrumental climate records from the three nearest meteorological stations, gridded climate data, and North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) indices. July extreme maximum temperatures (JulT emx ), as measured at Alert, Canada, June NAO, and previous October AO, together explained 41% of the observed variance in annual C. tetragona growth and likely represent in situ summer temperatures. JulT emx explained 27% and was reconstructed back to 1927. The reconstruction showed relatively high growing season temperatures in the early to mid-twentieth century, as well as warming in recent decades. The rapid growth increase in C. tetragona shrubs in response to recent High Arctic summer warming shows that recent and future warming might promote an expansion of this evergreen dwarf shrub, mainly through densification of existing shrub patches, at High Arctic sites with sufficient winter snow cover and ample water supply during summer from melting snow and ice as well as thawing permafrost, contrasting earlier notions of limited shrub growth sensitivity to

Abnormal Winter Melting of the Arctic Sea Ice Cap Observed by the Spaceborne Passive Microwave Sensors

Directory of Open Access Journals (Sweden)

Seongsuk Lee

2016-12-01

Full Text Available The spatial size and variation of Arctic sea ice play an important role in Earth’s climate system. These are affected by conditions in the polar atmosphere and Arctic sea temperatures. The Arctic sea ice concentration is calculated from brightness temperature data derived from the Defense Meteorological Satellite program (DMSP F13 Special Sensor Microwave/Imagers (SSMI and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS sensors. Many previous studies point to significant reductions in sea ice and their causes. We investigated the variability of Arctic sea ice using the daily and monthly sea ice concentration data from passive microwave observations to identify the sea ice melting regions near the Arctic polar ice cap. We discovered the abnormal melting of the Arctic sea ice near the North Pole even during the summer and the winter. This phenomenon is hard to explain only surface air temperature or solar heating as suggested by recent studies. We propose a hypothesis explaining this phenomenon. The heat from the deep sea in Arctic Ocean ridges and/or the hydrothermal vents might be contributing to the melting of Arctic sea ice. This hypothesis could be verified by the observation of warm water column structure below the melting or thinning arctic sea ice through the project such as Coriolis dataset for reanalysis (CORA.

The Arctic Human Health Initiative: a legacy of the International Polar Year 2007–2009

Directory of Open Access Journals (Sweden)

Alan J. Parkinson

2013-08-01

Full Text Available Background . The International Polar Year (IPY 2007–2008 represented a unique opportunity to further stimulate cooperation and coordination on Arctic health research and increase the awareness and visibility of Arctic regions. The Arctic Human Health Initiative (AHHI was a US-led Arctic Council IPY coordinating project that aimed to build and expand on existing International Union for Circumpolar Health (IUCH and Arctic Council human health interests. The project aimed to link researchers with potential international collaborators and to serve as a focal point for human health research, education, outreach and communication activities during the IPY. The progress of projects conducted as part of this initiative up until the end of the Arctic Council Swedish chairmanship in May 2013 is summarized in this report. Design . The overall goals of the AHHI was to increase awareness and visibility of human health concerns of Arctic peoples, foster human health research, and promote health strategies that will improve health and well-being of all Arctic residents. Proposed activities to be recognized through the initiative included: expanding research networks that will enhance surveillance and monitoring of health issues of concern to Arctic peoples, and increase collaboration and coordination of human health research; fostering research that will examine the health impact of anthropogenic pollution, rapid modernization and economic development, climate variability, infectious and chronic diseases, intentional and unintentional injuries, promoting education, outreach and communication that will focus public and political attention on Arctic health issues, using a variety of publications, printed and electronic reports from scientific conferences, symposia and workshops targeting researchers, students, communities and policy makers; promoting the translation of research into health policy and community action including implementation of prevention

Polar cloud observatory at Ny-Ålesund in GRENE Arctic Climate Change Research Project

Science.gov (United States)

Yamanouchi, Takashi; Takano, Toshiaki; Shiobara, Masataka; Okamoto, Hajime; Koike, Makoto; Ukita, Jinro

2016-04-01

Cloud is one of the main processes in the climate system and especially a large feed back agent for Arctic warming amplification (Yoshimori et al., 2014). From this reason, observation of polar cloud has been emphasized and 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard in 2013 as one of the basic infrastructure in the GRENE (Green Network of Excellence Program) Arctic Climate Change Research Project. The radar, "FALCON-A", is a FM-CW (frequency modulated continuous wave) Doppler radar, developed for Arctic use by Chiba University (PI: T. Takano) in 2012, following its prototype, "FALCON-1" which was developed in 2006 (Takano et al., 2010). The specifications of the radar are, central frequency: 94.84 GHz; antenna power: 1 W; observation height: up to 15 km; range resolution: 48 m; beam width: 0.2 degree (15 m at 5 km); Doppler width: 3.2 m/s; time interval: 10 sec, and capable of archiving high sensitivity and high spatial and time resolution. An FM-CW type radar realizes similar sensitivity with much smaller parabolic antennas separated 1.4 m from each other used for transmitting and receiving the wave. Polarized Micro-Pulse Lidar (PMPL, Sigma Space MPL-4B-IDS), which is capable to measure the backscatter and depolarization ratio, has also been deployed to Ny-Ålesund in March 2012, and now operated to perform collocated measurements with FALCON-A. Simultaneous measurement data from collocated PMPL and FALCON-A are available for synergetic analyses of cloud microphysics. Cloud mycrophysics, such as effective radius of ice particles and ice water content, are obtained from the analysis based on algorithm, which is modified for ground-based measurements from Okamoto's retrieval algorithm for satellite based cloud profiling radar and lidar (CloudSat and CALIPSO; Okamoto et al., 2010). Results of two years will be shown in the presentation. Calibration is a point to derive radar reflectivity (dBZ) from original intensity data

Research Experience for Undergraduates: Understanding the Arctic as a System

Science.gov (United States)

Alexeev, V. A.; Walsh, J. E.; Arp, C. D.; Hock, R.; Euskirchen, E. S.; Kaden, U.; Polyakov, I.; Romanovsky, V. E.; Trainor, S.

2017-12-01

Today, more than ever, an integrated cross-disciplinary approach is necessary to understand and explain changes in the Arctic and the implications of those changes. Responding to needs in innovative research and education for understanding high-latitude rapid climate change, scientists at the International Arctic research Center of the University of Alaska Fairbanks (UAF) established a new REU (=Research Experience for Undergraduates) NSF-funded site, aiming to attract more undergraduates to arctic sciences. The science focus of this program, building upon the research strengths of UAF, is on understanding the Arctic as a system with emphasis on its physical component. The goals, which were to disseminate new knowledge at the frontiers of polar science and to ignite the enthusiasm of the undergraduates about the Arctic, are pursued by involving undergraduate students in research and educational projects with their mentors using the available diverse on-campus capabilities. IARC hosted the first group of eight students this past summer, focusing on a variety of different disciplines of the Arctic System Science. Students visited research sites around Fairbanks and in remote parts of Alaska (Toolik Lake Field Station, Gulkana glacier, Bonanza Creek, Poker Flats, the CRREL Permafrost Tunnel and others) to see and experience first-hand how the arctic science is done. Each student worked on a research project guided by an experienced instructor. The summer program culminated with a workshop that consisted of reports from the students about their experiences and the results of their projects.

Review of Arctic fox. Life at the top of the world, by Gary Hamilton

OpenAIRE

Ims, Rolf A.

2009-01-01

The Arctic fox is the only truly Arctic species among the terrestrial carnivorous mammals of the world. It is distributed across the circumpolar Arctic region. Like polar bears, Arctic foxes regularly traverse the pack ice of the polar basin, a fact that astonished Fridtjof Nansen during his attempt to reach the North Pole more than 100 years ago. However, despite its unique lifestyle, which in some respects is more fascinating than that of the polar bear, there has been no popular book (exce...

Distributions of Polycyclic Aromatic Hydrocarbons, Aromatic Ketones, Carboxylic Acids, and Trace Metals in Arctic Aerosols: Long-Range Atmospheric Transport, Photochemical Degradation/Production at Polar Sunrise.

Science.gov (United States)

Singh, Dharmendra Kumar; Kawamura, Kimitaka; Yanase, Ayako; Barrie, Leonard A

2017-08-15

The distributions, correlations, and source apportionment of aromatic acids, aromatic ketones, polycyclic aromatic hydrocarbons (PAHs), and trace metals were studied in Canadian high Arctic aerosols. Nineteen PAHs including minor sulfur-containing heterocyclic PAH (dibenzothiophene) and major 6 carcinogenic PAHs were detected with a high proportion of fluoranthene followed by benzo[k]fluoranthene, pyrene, and chrysene. However, in the sunlit period of spring, their concentrations significantly declined likely due to photochemical decomposition. During the polar sunrise from mid-March to mid-April, benzo[a]pyrene to benzo[e]pyrene ratios significantly dropped, and the ratios diminished further from late April to May onward. These results suggest that PAHs transported over the Arctic are subjected to strong photochemical degradation at polar sunrise. Although aromatic ketones decreased in spring, concentrations of some aromatic acids such as benzoic and phthalic acids increased during the course of polar sunrise, suggesting that aromatic hydrocarbons are oxidized to result in aromatic acids. However, PAHs do not act as the major source for low molecular weight (LMW) diacids such as oxalic acid that are largely formed at polar sunrise in the arctic atmosphere because PAHs are 1 to 2 orders of magnitude less abundant than LMW diacids. Correlations of trace metals with organics, their sources, and the possible role of trace transition metals are explained.

Polar bears and sea ice habitat change

Science.gov (United States)

Durner, George M.; Atwood, Todd C.; Butterworth, Andy

2017-01-01

The polar bear (Ursus maritimus) is an obligate apex predator of Arctic sea ice and as such can be affected by climate warming-induced changes in the extent and composition of pack ice and its impacts on their seal prey. Sea ice declines have negatively impacted some polar bear subpopulations through reduced energy input because of loss of hunting habitats, higher energy costs due to greater ice drift, ice fracturing and open water, and ultimately greater challenges to recruit young. Projections made from the output of global climate models suggest that polar bears in peripheral Arctic and sub-Arctic seas will be reduced in numbers or become extirpated by the end of the twenty-first century if the rate of climate warming continues on its present trajectory. The same projections also suggest that polar bears may persist in the high-latitude Arctic where heavy multiyear sea ice that has been typical in that region is being replaced by thinner annual ice. Underlying physical and biological oceanography provides clues as to why polar bear in some regions are negatively impacted, while bears in other regions have shown no apparent changes. However, continued declines in sea ice will eventually challenge the survival of polar bears and efforts to conserve them in all regions of the Arctic.

Polar bears at risk

Energy Technology Data Exchange (ETDEWEB)

Norris, S.; Rosentrater, L.; Eid, P.M. [WWF International Arctic Programme, Oslo (Norway)

2002-05-01

Polar bears, the world's largest terrestrial carnivore, spend much of their lives on the arctic sea ice. This is where they hunt and move between feeding, denning, and resting areas. The world population, estimated at 22,000 bears, is made up of 20 relatively distinct populations varying in size from a few hundred to a few thousand animals. About 60 per cent of all polar bears are found in Canada. In general, the status of this species is stable, although there are pronounced differences between populations. Reductions in the extent and thickness of sea ice has lead the IUCN Polar Bear Specialist Group to describe climate change as one of the major threats facing polar bears today. Though the long-term effects of climate change will vary in different areas of the Arctic, impacts on the condition and reproductive success of polar bears and their prey are likely to be negative. Longer ice-free periods resulting from earlier break-up of sea ice in the spring and later formation in the fall is already impacting polar bears in the southern portions of their range. In Canada's Hudson Bay, for example, bears hunt on the ice through the winter and into early summer, after which the ice melts completely, forcing bears ashore to fast on stored fat until freeze-up in the fall. The time bears have on the ice to hunt and build up their body condition is cut short when the ice melts early. Studies from Hudson Bay show that for every week earlier that ice break-up occurs, bears will come ashore 10 kg lighter and in poorer condition. It is likely that populations of polar bears dividing their time between land and sea will be severely reduced and local extinctions may occur as greenhouse gas emissions continue to rise and sea ice melts. Expected changes in regional weather patterns will also impact polar bears. Rain in the late winter can cause maternity dens to collapse before females and cubs have departed, thus exposing occupants to the elements and to predators. Such

Mercury speciation in brain tissue of polar bears (Ursus maritimus) from the Canadian Arctic.

Science.gov (United States)

Krey, Anke; Kwan, Michael; Chan, Hing Man

2012-04-01

Methylmercury (MeHg) is a neurotoxicant that has been found at elevated concentrations in the Arctic ecosystem. Little is known about its internal dose in wildlife such as polar bears. We measured concentrations of mercury (Hg) in three different brain regions (cerebellum, frontal lobe and brain stem) of 24 polar bears collected from the Nunavik, Canada between 2000 and 2003. Speciation of Hg was measured by High Performance Liquid Chromatography coupled to Inductively Coupled Plasma Mass Spectroscopy (HPLC-ICP-MS). Concentrations of mean total Hg in brain tissue were up to 625 times lower (0.28 ± 0.07 mg kg(-1) dry weight (dw) in frontal lobe, 0.23 ± 0.07 mg kg(-1) dw in cerebellum and 0.12 ± 0.0 3mg kg(-1) dw in brain stem) than the mean total Hg concentration previously reported in polar bear liver collected from Eastern Baffin Island. Methylmercury (MeHg) accounted for 100% of the Hg found in all three brain regions analyzed. These results suggest that polar bear might reduce the toxic effects of Hg by limiting the uptake into the brain and/or decrease the rate of demethylation so that Hg can be excreted from the brain more easily. The toxicokinetics and the blood-brain-barrier mechanisms of polar bears are still unknown and further research is required. Copyright © 2012 Elsevier Inc. All rights reserved.

Building Transferable Knowledge and Skills through an Interdisciplinary Polar Science Graduate Program

Science.gov (United States)

Culler, L. E.; Virginia, R. A.; Albert, M. R.; Ayres, M.

2015-12-01

Modern graduate education must extend beyond disciplinary content to prepare students for diverse careers in science. At Dartmouth, a graduate program in Polar Environmental Change uses interdisciplinary study of the polar regions as a core from which students develop skills and knowledge for tackling complex environmental issues that require cooperation across scientific disciplines and with educators, policy makers, and stakeholders. Two major NSF-funded initiatives have supported professional development for graduate students in this program, including an IGERT (Integrative Graduate Education and Research Traineeship) and leadership of JSEP's (Joint Science Education Project) Arctic Science Education Week in Greenland. We teach courses that emphasize the links between science and the human dimensions of environmental change; host training sessions in science communication; invite guest speakers who work in policy, academia, journalism, government research, etc.; lead an international field-based training that includes policy-focused meetings and a large outreach component; provide multiple opportunities for outreach and collaboration with local schools; and build outreach and education into graduate research programs where students instruct and mentor high school students. Students from diverse scientific disciplines (Ecology, Earth Science, and Engineering) participate in all of the above, which significantly strengthens their interdisciplinary view of polar science and ability to communicate across disciplines. In addition, graduate students have developed awareness, confidence, and the skills to pursue and obtain diverse careers. This is reflected in the fact that recent graduates have acquired permanent and post-doctoral positions in academic and government research, full-time teaching, and also in post-docs focused on outreach and science policy. Dartmouth's interdisciplinary approach to graduate education is producing tomorrow's leaders in science.

Comparative hepatic in vitro depletion and metabolite formation of major perfluorooctane sulfonate precursors in Arctic polar bear, beluga whale, and ringed seal.

Science.gov (United States)

Letcher, Robert J; Chu, Shaogang; McKinney, Melissa A; Tomy, Gregg T; Sonne, Christian; Dietz, Rune

2014-10-01

Perfluorooctane sulfonate (PFOS) has been reported to be among the most concentrated persistent organic pollutants in Arctic marine wildlife. The present study examined the in vitro depletion of major PFOS precursors, N-ethyl-perfluorooctane sulfonamide (N-EtFOSA) and perfluorooctane sulfonamide (FOSA), as well as metabolite formation using an assay based on enzymatically viable liver microsomes for three top Arctic marine mammalian predators, polar bear (Ursus maritimus), beluga whale (Delphinapterus leucas), and ringed seal (Pusa hispida), and in laboratory rat (Rattus rattus) serving as a general mammalian model and positive control. Rat assays showed that N-EtFOSA (38 nM or 150 ng mL(-1)) to FOSA metabolism was >90% complete after 10 min, and at a rate of 23 pmol min(-1) mg(-1) protein. Examining all species in a full 90 min incubation assay, there was >95% N-EtFOSA depletion for the rat active control and polar bear microsomes, ∼65% for ringed seals, and negligible depletion of N-EtFOSA for beluga whale. Concomitantly, the corresponding in vitro formation of FOSA from N-EtFOSA was also quantitatively rat≈polar bear>ringed seal>beluga whale. A lack of enzymatic ability and/or a rate too slow to be detected likely explains the lack of N-EtFOSA to FOSA transformation for beluga whale. In the same assays, the depletion of the FOSA metabolite was insignificant (p>0.01) and with no concomitant formation of PFOS metabolite. This suggests that, in part, a source of FOSA is the biotransformation of accumulated N-EtFOSA in free-ranging Arctic ringed seal and polar bear. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Across the Arctic Teachers Experience Field Research

Science.gov (United States)

Warnick, W. K.; Warburton, J.; Wiggins, H. V.; Marshall, S. A.; Darby, D. A.

2005-12-01

From studying snow geese on the North Slope of Alaska to sediment coring aboard the U.S. Coast Guard Cutter Healy in the Arctic Ocean, K-12 teachers embark on scientific expeditions as part of a program that strives to make science in the Arctic a "virtual" reality. In the past two years, seventeen K-12 teachers have participated in Teachers and Researchers Exploring and Collaborating (TREC), a program that pairs teachers with researchers to improve science education through arctic field experiences. TREC builds on the scientific and cultural opportunities of the Arctic, linking research and education through topics that naturally engage students and the wider public. TREC includes expeditions as diverse as studying plants at Toolik Field Station, a research facility located 150 miles above the Arctic Circle; climate change studies in Norway's Svalbard archipelago; studying rivers in Siberia; or a trans-arctic expedition aboard the USCGC Healy collecting an integrated geophysical data set. Funded by the National Science Foundation Office of Polar Programs, TREC offers educators experiences in scientific inquiry while encouraging the public and students to become active participants in the scientific inquiry by engaging them virtually in arctic research. TREC uses online outreach elements to convey the research experience to a broad audience. While in remote field locations, teachers and researchers interact with students and the public through online seminars and live calls from the field, online journals with accompanying photos, and online bulletin boards. Since the program's inception in 2004, numerous visitors have posted questions or interacted with teachers, researchers, and students through the TREC website (http://www.arcus.org/trec). TREC teachers are required to transfer their experience of research and current science into their classroom through the development of relevant activities and resources. Teachers and researchers are encouraged to participate

The polar bear in the room: diseases of poverty in the Arctic

Directory of Open Access Journals (Sweden)

Chris Nelson

2013-08-01

Full Text Available In the face of global warming, budgetary austerity and impoverished Arctic residents, the nations of the circumpolar region are presented with a number of difficult choices regarding the provision of health care to the far-flung and isolated regions of their northernmost provinces. Complicating that picture is the reality of neglected tropical diseases in areas far from their perceived normal equatorial range as well as endemic food-borne diseases, including protozoan and helminth parasites, respiratory and gastrointestinal diseases and vaccine-preventable illnesses. This paper discusses the problems of caring for the health and well-being of indigenous populations suffering from extreme poverty, isolation and discrimination in the circumpolar region. After presenting difficulties as supported by the extant literature, the paper continues by suggesting solutions that include novel telenursing applications, targeted distance-educational programs and local community-based health care assistant (HCA vocational training. These programs will provide cost-effective care that increases life-spans, improves quality of life and provides opportunities to distressed populations in isolated rural communities of the Far North. The toolkit presented in the paper is intended to spur discussion on community health programs that could be adopted to provide proper and humane care for marginalized Arctic populations in an extreme and rapidly changing environment.

Chlorinated hydrocarbon contaminants in arctic marine mammals.

Science.gov (United States)

Norstrom, R J; Muir, D C

1994-09-16

By 1976, the presence of chlorinated hydrocarbon contaminants (CHCs) had been demonstrated in fur seal (Callorhinus ursinus), ringed seal (Phoca hispida), hooded seal (Cystophora cristata), bearded seal (Erignathus barbatus), walrus (Obdobenus rosmarus divergens), beluga (Delphinapterus leucas), porpoise (Phocoena phocoena) and polar bear (Ursus maritimus) in various parts of the Arctic. In spite of this early interest, very little subsequent research on contaminants in Arctic marine mammals was undertaken until the mid-1980s. Since that time, there has been an explosion of interest, resulting in a much expanded data base on contaminants in Arctic marine mammals. Except in the Russian Arctic, data have now been obtained on the temporospatial distribution of PCBs and other contaminants in ringed seal, beluga and polar bear. Contaminants in narwhal (Monodon monoceros) have also now been measured. On a fat weight basis, the sum of DDT-related compounds (S-DDT) and PCB levels are lowest in walrus (Polar bears have similar levels of PCBs as cetaceans (1-10 micrograms/g), but with a much simpler congener pattern. DDE levels are lowest in polar bear, indicating rapid metabolism. Effects of age and sex on residue levels are found for all species where this was measured. Among cetaceans and ringed seal, sexually mature females have lower levels than males due to lactation. Although PCB levels in adult male polar bears are about twice as high as females, there is only a trivial age effect in either sex apart from an initial decrease from birth to sexual maturity (age 0-5). Comparison of levels of S-DDT and PCBs in Arctic beluga and ringed seal with those in beluga in the Gulf of St. Lawrence and ringed seal in the Baltic Sea, indicate that overall contamination of the Arctic marine ecosystem is 10-50 times less than the most highly contaminated areas in the northern hemisphere temperate latitude marine environment. Geographic distribution of residue levels in polar bears

Polar gravity fields from GOCE and airborne gravity

DEFF Research Database (Denmark)

Forsberg, René; Olesen, Arne Vestergaard; Yidiz, Hasan

2011-01-01

Airborne gravity, together with high-quality surface data and ocean satellite altimetric gravity, may supplement GOCE to make consistent, accurate high resolution global gravity field models. In the polar regions, the special challenge of the GOCE polar gap make the error characteristics...... of combination models especially sensitive to the correct merging of satellite and surface data. We outline comparisons of GOCE to recent airborne gravity surveys in both the Arctic and the Antarctic. The comparison is done to new 8-month GOCE solutions, as well as to a collocation prediction from GOCE gradients...... in Antarctica. It is shown how the enhanced gravity field solutions improve the determination of ocean dynamic topography in both the Arctic and in across the Drake Passage. For the interior of Antarctica, major airborne gravity programs are currently being carried out, and there is an urgent need...

Final Technical Report for Project 'Improving the Simulation of Arctic Clouds in CCSM3 (SGER Award)'

International Nuclear Information System (INIS)

Vavrus, Stephen J.

2008-01-01

climate model. J. Climate, 21, 5673-5687.). The article also provides a novel synthesis of surface- and satellite-based Arctic cloud observations that show how much the new freezedry parameterization improves the simulated cloud amount in high latitudes (Fig. 3). Freezedry has been incorporated into the CCSM3.5 version, in which it successfully limits the excessive polar clouds, and may be used in CCSM4. Material from this work is also appearing in a synthesis article on future Arctic cloud changes (Vavrus, D. Waliser, J. Francis, and A. Schweiger, 'Simulations of 20th and 21st century Arctic cloud amount in the global climate models assessed in the IPCC AR4', accepted in Climate Dynamics) and was used in a collaborative paper on Arctic cloud-sea ice coupling (Schweiger, A., R. Lindsay, S. Vavrus, and J. Francis, 2008: Relationships between Arctic sea ice and clouds during autumn. J. Climate, 21, 4799-4810.). This research was presented at the 2007 CCSM Annual Workshop, as well as the CCSM's 2007 Atmospheric Model Working Group and Polar Working Group Meetings. The findings were also shown at the 2007 Climate Change Prediction Program's Science Team Meeting. In addition, I served as an instructor at the International Arctic Research Center's (IARC) Summer School on Arctic Climate Modeling in Fairbanks this summer, where I presented on the challenges and techniques used in simulating polar clouds. I also contributed to the development of a new Arctic System Model by attending a workshop in Colorado this summer on this fledgling project. Finally, an outreach activity for the general public has been the development of an interactive web site ( ) that displays Arctic cloud amount in the CMIP3 climate model archive under present and future scenarios. This site allows users to make polar and global maps of a variety of climate variables to investigate the individual and ensemble-mean GCM response to greenhouse warming and the extent to which models adequately represent Arctic

PolarTREC-Teachers and Researchers Exploring and Collaborating: Science Education from the Poles to the World

Science.gov (United States)

Warnick, W. K.; Breen, K.; Warburton, J.; Fischer, K.; Wiggins, H.; Owens, R.; Polly, B.; Wade, B.; Buxbaum, T.

2007-12-01

PolarTREC-Teachers and Researchers Exploring and Collaborating is a three-year (2007-2009) teacher professional development program celebrating the International Polar Year (IPY) that advances polar science education by bringing K-12 educators and polar researchers together in hands-on field experiences in the Arctic and Antarctic. Currently in its second year, the program fosters the integration of research and education to produce a legacy of long-term teacher-researcher collaborations, improved teacher content knowledge through experiences in scientific inquiry, and broad public interest and engagement in polar science. Through PolarTREC, over 40 U.S. teachers will spend two to six weeks in the Arctic or Antarctic, working closely with researchers in the field as an integral part of the science team. Research projects focus on a wide range of IPY science themed topics such as sea-ice dynamics, terrestrial ecology, marine biology, atmospheric chemistry, and long-term climate change. While in the field, teachers and researchers will communicate extensively with their colleagues, communities, and hundreds of students of all ages across the globe, using a variety of tools including satellite phones, online journals, podcasts and interactive "Live from IPY" calls and web-based seminars. The online outreach elements of the project convey these experiences to a broad audience far beyond the classrooms of the PolarTREC teachers. In addition to field research experiences, PolarTREC will support teacher professional development and a sustained community of teachers, scientists, and the public through workshops, Internet seminars, an e-mail listserve, and teacher peer groups. To learn more about PolarTREC visit the website at: http://www.polartrec.com or contact info@polartrec.com or 907-474-1600. PolarTREC is funded by NSF and managed by the Arctic Research Consortium of the US (ARCUS).

Protists in the polar regions: comparing occurrence in the Arctic and Southern oceans using pyrosequencing

Directory of Open Access Journals (Sweden)

Christian Wolf

2015-05-01

Full Text Available In the ongoing discussion of the distribution of protists, whether they are globally distributed or endemic to one or both of the polar regions is the subject of heated debate. In this study, we compared next-generation sequencing data from the Arctic and the Southern oceans to reveal the extent of similarities and dissimilarities between the protist communities in the polar regions. We found a total overlap of operational taxonomic units (OTUs between the two regions of 11.2%. On closer inspection of different taxonomic groups, the overlap ranged between 5.5% (haptophytes and 14.5% (alveolates. Within the different groups, the proportion of OTUs occurring in both regions greatly differed between the polar regions. On the one hand, the overlap between these two regions is remarkable, given the geographical distance between them. On the other hand, one could expect a greater overlap of OTUs between these regions on account of the similar environmental conditions. The overlap suggests a connection between the polar regions for at least certain species or that the evolutionary divergence has been slow, relative to the timescales of isolation. The different proportions of common OTUs among the groups or regions may be a result of different life cycle strategies or environmental adaptations.

Tolerance of polar phytoplankton communities to metals

International Nuclear Information System (INIS)

Echeveste, P.; Tovar-Sánchez, A.; Agustí, S.

2014-01-01

Large amounts of pollutants reach polar regions, particularly the Arctic, impacting their communities. In this study we analyzed the toxic levels of Hg, Cd and Pb to natural phytoplankton communities of the Arctic and Southern Oceans, and compared their sensitivities with those observed on phytoplankton natural communities from temperate areas. Mercury was the most toxic metal for both Arctic and Antarctic communities, while both Cd and Pb were toxic only for the Antarctic phytoplankton. Total cell abundance of the populations forming the Arctic community increased under high Cd and Pb concentrations, probably due to a decrease of the grazing pressure or the increase of the most resistant species, although analysis of individual cells indicated that cell death was already induced at the highest levels. These results suggest that phytoplankton may have acquired adapting mechanisms to face high levels of Pb and Cd in the Arctic Ocean. Highlights: • First study analyzing the toxicity of Hg, Cd or Pb to natural polar phytoplankton. • Arctic Ocean communities highly resistant to Cd and Pb, but not to Hg. • Southern Ocean communities sensitive to Cd, Pb and Hg. • Both communities incorporated Pb at a similar level. • Arctic phytoplankton may have acquired adapting mechanisms against Cd and Pb. -- Polar phytoplankton communities are tolerant to Cd and Pb, specially the Arctic ones, suggesting the acquisition of adapting mechanisms to face metals' toxicity

Contamination of the Arctic by exotic air toxics

International Nuclear Information System (INIS)

Ford, J.; Landers, D.

1991-01-01

Various kinds of atmospheric pollutants are commonly known to occur in arctic environments. These include organic contaminants, pollutants associated with fossil fuel combustion, smelting, industrial development, and radionuclides. Recently, additional concern has arisen from studies suggesting that at least some atmospheric contaminants may be susceptible to poleward redistribution as a result of their physical and chemical properties. Thus, contamination of the arctic may be exacerbated by the tendency of selected contaminants produced at lower latitudes to be transported to polar regions and incorporated into high latitude food chains. Although awareness of exotic contaminants in high latitude food chains is not new, regional baseline data are needed to document the spatial extent and magnitude of this potentially serious problem. The US Arctic is little studied in this regard relative to several other circumpolar nations (e.g., Canada, Sweden); over the next year the authors will be designing a regional survey to begin remedying this information gap. A major focus of this activity will be to ensure compatibility with both ongoing international studies of arctic contamination, and the USEPA Environmental Monitoring and Assessment Program. Issues related to sampling design will be outlined and discussed

Longer ice-free seasons increase the risk of nest depredation by polar bears for colonial breeding birds in the Canadian Arctic.

Science.gov (United States)

Iverson, Samuel A; Gilchrist, H Grant; Smith, Paul A; Gaston, Anthony J; Forbes, Mark R

2014-03-22

Northern polar regions have warmed more than other parts of the globe potentially amplifying the effects of climate change on biological communities. Ice-free seasons are becoming longer in many areas, which has reduced the time available to polar bears (Ursus maritimus) to hunt for seals and hampered bears' ability to meet their energetic demands. In this study, we examined polar bears' use of an ancillary prey resource, eggs of colonial nesting birds, in relation to diminishing sea ice coverage in a low latitude region of the Canadian Arctic. Long-term monitoring reveals that bear incursions onto common eider (Somateria mollissima) and thick-billed murre (Uria lomvia) nesting colonies have increased greater than sevenfold since the 1980s and that there is an inverse correlation between ice season length and bear presence. In surveys encompassing more than 1000 km of coastline during years of record low ice coverage (2010-2012), we encountered bears or bear sign on 34% of eider colonies and estimated greater egg loss as a consequence of depredation by bears than by more customary nest predators, such as foxes and gulls. Our findings demonstrate how changes in abiotic conditions caused by climate change have altered predator-prey dynamics and are leading to cascading ecological impacts in Arctic ecosystems.

The Arctic : the great breakup

International Nuclear Information System (INIS)

Lemieux, R.

2007-01-01

The impact that climate change has had on the famous Northwest passage in Canada's Arctic was discussed. The water channel through the Arctic Islands is now navigable during the summer and it has been predicted that in 40 years, it may be navigable throughout the entire year. Although the Arctic is still covered with snow, the icebergs which navigators have feared no longer exist. Environment Canada has cautioned that Canada's extreme north would be most at risk from global warming, with temperatures increasing by 6 degrees, or 3 times higher than in moderate zones. The joint Canadian-United States program Surface Heat Budget of the Arctic has also confirmed that the waters of the Beaufort Sea are less salty and relatively warmer. Climatologists also project that the predicted increase in snowfall will act as an insulation blanket, thereby preventing the ice from thickening. Scientists stated that the gigantic polar cap, which has been frozen for the past 3.2 million years, will have fissures everywhere by 2080. The Northwest passage will become easily accessible in less than 10 years. This article raised questions regarding the role of the Northwest passage as an international maritime route. It presented the case of the first successful passage of a U.S. commercial oil tanker in 1969 which created controversy regarding Canada's territorial waters. Fourty years later, this issue is still not resolved. The article questioned whether there should be more cooperation on both the Canadian and American sides in light of the shared common interests such as commerce, science and security. It was noted that although Canada has sovereignty of the Arctic Islands, there are eight other countries who share the Arctic. 4 figs

High bacterial diversity of biological soil crusts in water tracks over permafrost in the high arctic polar desert.

Science.gov (United States)

Steven, Blaire; Lionard, Marie; Kuske, Cheryl R; Vincent, Warwick F

2013-01-01

In this study we report the bacterial diversity of biological soil crusts (biocrusts) inhabiting polar desert soils at the northern land limit of the Arctic polar region (83° 05 N). Employing pyrosequencing of bacterial 16S rRNA genes this study demonstrated that these biocrusts harbor diverse bacterial communities, often as diverse as temperate latitude communities. The effect of wetting pulses on the composition of communities was also determined by collecting samples from soils outside and inside of permafrost water tracks, hill slope flow paths that drain permafrost-affected soils. The intermittent flow regime in the water tracks was correlated with altered relative abundance of phylum level taxonomic bins in the bacterial communities, but the alterations varied between individual sampling sites. Bacteria related to the Cyanobacteria and Acidobacteria demonstrated shifts in relative abundance based on their location either inside or outside of the water tracks. Among cyanobacterial sequences, the proportion of sequences belonging to the family Oscillatoriales consistently increased in relative abundance in the samples from inside the water tracks compared to those outside. Acidobacteria showed responses to wetting pulses in the water tracks, increasing in abundance at one site and decreasing at the other two sites. Subdivision 4 acidobacterial sequences tended to follow the trends in the total Acidobacteria relative abundance, suggesting these organisms were largely responsible for the changes observed in the Acidobacteria. Taken together, these data suggest that the bacterial communities of these high latitude polar biocrusts are diverse but do not show a consensus response to intermittent flow in water tracks over high Arctic permafrost.

Facilitating Participant Success: Teachers Experiencing Antarctica and the Arctic Program

Science.gov (United States)

Shipp, S. S.; Bruccoli, A.; Porter, M.; Meese, D.

2003-12-01

Through the NSF-funded Teachers Experiencing Antarctica and the Arctic (TEA) Program K-12 science teachers participate as members of polar field projects. Objectives of the program include: immersing the science teacher in the experience of research; 2) leveraging the research experience of the teacher to better inform teaching practices; and 3) sharing the experience with the broader educational and general community. The polar field experience is an exciting opportunity accompanied by a daunting number of responsibilities. In addition to preparing for field research, TEA teachers bring their experience to colleagues, classrooms, and communities. Before going into the field, they give presentations, help plan how students can connect to the polar regions, and share the expedition with the public. In the field, the TEA teacher is a team member and educational liaison, responding to questions by e-mail, and posting e-journals describing the research experience. Upon return, the TEA again shares the experience broadly with the community. In addition, they work closely with 3 colleagues for 140 hours to bring the experience of research into classrooms. Formative evaluation of the TEA Program underscores the need to support teachers in accomplishing their responsibilities; this support is necessary to achieve program objectives. TEA teachers are responsible for sharing the science content of their research. While many broadcast the excitement of the experience, they may not have the scientific background to convey the content. This is due, in part, to many teachers having to be generalists in their classrooms. Shifting into the role of specialist can be challenging. In the year of preparation before the field experience, TEA teachers attend orientation, meet with their research teams for several days, and are encouraged to learn more about their science topic. Understanding builds through the field experience. It may take two or more years after the field work for the

The Temperature of the Arctic and Antarctic Lower Stratosphere

Science.gov (United States)

Newman, Paul A.; Nash, Eric R.; Bhartia, P. K. (Technical Monitor)

2002-01-01

The temperature of the polar lower stratosphere during spring is the key factor in changing the magnitude of ozone loss in the polar vortices. In this talk, we will review the results of Newman et al. [2000] that quantitatively demonstrate that the polar lower stratospheric temperature is primarily controlled by planetary-scale waves. In particular, the tropospheric eddy heat flux in middle to late winter (January--February) is highly correlated with the mean polar stratospheric temperature during March. Strong midwinter planetary wave forcing leads to a warmer spring Arctic lower stratosphere in early spring, while weak midwinter forcing leads to cooler spring Arctic temperatures. In addition, this planetary wave driving also has a strong impact on the strength of the polar vortex. These results from the Northern Hemisphere will be contrasted with the Southern Hemisphere.

What Controls the Temperature of the Arctic Stratosphere during the Spring?

Science.gov (United States)

Newman, Paul A.; Nash, Eric R.; Rosenfield, Joan E.; Einaudi, Franco (Technical Monitor)

2000-01-01

Understanding the mechanisms that control the temperature of the polar lower stratosphere during spring is key to understanding ozone loss in the Arctic polar vortex. Spring ozone loss rates are directly tied to polar stratospheric temperatures by the formation of polar stratospheric clouds, and the conversion of chlorine species to reactive forms on these cloud particle surfaces. In this paper, we study those factors that control temperatures in the polar lower stratosphere. We use the National Centers for Environmental Prediction (NCEP)/NCAR reanalysis data covering the last two decades to investigate how planetary wave driving of the stratosphere is connected to polar temperatures. In particular, we show that planetary waves forced in the troposphere in mid- to late winter (January-February) are principally responsible for the mean polar temperature during the March period. These planetary waves are forced by both thermal and orographic processes in the troposphere, and propagate into the stratosphere in the mid and high latitudes. Strong mid-winter planetary wave forcing leads to a warmer Arctic lower stratosphere in early spring, while weak mid-winter forcing leads to cooler Arctic temperatures.

Absolute Geostrophic Velocity Inverted from the Polar Science Center Hydrographic Climatology (PHC3.0) of the Arctic Ocean with the P-Vector Method (NCEI Accession 0156425)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The dataset (called PHC-V) comprises 3D gridded climatological fields of absolute geostrophic velocity of the Arctic Ocean inverted from the Polar science center...

Genomics of Arctic cod

Science.gov (United States)

Wilson, Robert E.; Sage, George K.; Sonsthagen, Sarah A.; Gravley, Megan C.; Menning, Damian; Talbot, Sandra L.

2017-01-01

The Arctic cod (Boreogadus saida) is an abundant marine fish that plays a vital role in the marine food web. To better understand the population genetic structure and the role of natural selection acting on the maternally-inherited mitochondrial genome (mitogenome), a molecule often associated with adaptations to temperature, we analyzed genetic data collected from 11 biparentally-inherited nuclear microsatellite DNA loci and nucleotide sequence data from from the mitochondrial DNA (mtDNA) cytochrome b (cytb) gene and, for a subset of individuals, the entire mitogenome. In addition, due to potential of species misidentification with morphologically similar Polar cod (Arctogadus glacialis), we used ddRAD-Seq data to determine the level of divergence between species and identify species-specific markers. Based on the findings presented here, Arctic cod across the Pacific Arctic (Bering, Chukchi, and Beaufort Seas) comprise a single panmictic population with high genetic diversity compared to other gadids. High genetic diversity was indicated across all 13 protein-coding genes in the mitogenome. In addition, we found moderate levels of genetic diversity in the nuclear microsatellite loci, with highest diversity found in the Chukchi Sea. Our analyses of markers from both marker classes (nuclear microsatellite fragment data and mtDNA cytb sequence data) failed to uncover a signal of microgeographic genetic structure within Arctic cod across the three regions, within the Alaskan Beaufort Sea, or between near-shore or offshore habitats. Further, data from a subset of mitogenomes revealed no genetic differentiation between Bering, Chukchi, and Beaufort seas populations for Arctic cod, Saffron cod (Eleginus gracilis), or Walleye pollock (Gadus chalcogrammus). However, we uncovered significant differences in the distribution of microsatellite alleles between the southern Chukchi and central and eastern Beaufort Sea samples of Arctic cod. Finally, using ddRAD-Seq data, we

Public Perceptions of Arctic Change

Science.gov (United States)

Hamilton, L.

2014-12-01

What does the general US public know, or think they know, about Arctic change? Two broad nationwide surveys in 2006 and 2010 addressed this topic in general terms, before and after the International Polar Year (IPY). Since then a series of representative national or statewide surveys have carried this research farther. The new surveys employ specific questions that assess public knowledge of basic Arctic facts, along with perceptions about the possible consequences of future Arctic change. Majorities know that late-summer Arctic sea ice area has declined compared with 30 years ago, although substantial minorities -- lately increasing -- believe instead that it has now recovered to historical levels. Majorities also believe that, if the Arctic warms in the future, this will have major effects on the weather where they live. Their expectation of local impacts from far-away changes suggests a degree of global thinking. On the other hand, most respondents do poorly when asked whether melting Arctic sea ice, melting Greenland/Antarctic land ice, or melting Himalayan glaciers could have more effect on sea level. Only 30% knew or guessed the right answer to this question. Similarly, only 33% answered correctly on a simple geography quiz: whether the North Pole could best be described as ice a few feet or yards thick floating over a deep ocean, ice more than a mile thick over land, or a rocky, mountainous landscape. Close analysis of response patterns suggests that people often construct Arctic "knowledge" on items such as sea ice increase/decrease from their more general ideology or worldview, such as their belief (or doubt) that anthropogenic climate change is real. When ideology or worldviews provide no guidance, as on the North Pole or sealevel questions, the proportion of accurate answers is no better than chance. These results show at least casual public awareness and interest in Arctic change, unfortunately not well grounded in knowledge. Knowledge problems seen on

Collaborative Research: Improving Decadal Prediction of Arctic Climate Variability and Change Using a Regional Arctic

Energy Technology Data Exchange (ETDEWEB)

Gutowski, William J. [Iowa State Univ., Ames, IA (United States)

2017-12-28

This project developed and applied a regional Arctic System model for enhanced decadal predictions. It built on successful research by four of the current PIs with support from the DOE Climate Change Prediction Program, which has resulted in the development of a fully coupled Regional Arctic Climate Model (RACM) consisting of atmosphere, land-hydrology, ocean and sea ice components. An expanded RACM, a Regional Arctic System Model (RASM), has been set up to include ice sheets, ice caps, mountain glaciers, and dynamic vegetation to allow investigation of coupled physical processes responsible for decadal-scale climate change and variability in the Arctic. RASM can have high spatial resolution (~4-20 times higher than currently practical in global models) to advance modeling of critical processes and determine the need for their explicit representation in Global Earth System Models (GESMs). The pan-Arctic region is a key indicator of the state of global climate through polar amplification. However, a system-level understanding of critical arctic processes and feedbacks needs further development. Rapid climate change has occurred in a number of Arctic System components during the past few decades, including retreat of the perennial sea ice cover, increased surface melting of the Greenland ice sheet, acceleration and thinning of outlet glaciers, reduced snow cover, thawing permafrost, and shifts in vegetation. Such changes could have significant ramifications for global sea level, the ocean thermohaline circulation and heat budget, ecosystems, native communities, natural resource exploration, and commercial transportation. The overarching goal of the RASM project has been to advance understanding of past and present states of arctic climate and to improve seasonal to decadal predictions. To do this the project has focused on variability and long-term change of energy and freshwater flows through the arctic climate system. The three foci of this research are: - Changes

A case study of high Arctic anthropogenic disturbance to polar desert permafrost and ecosystems

Science.gov (United States)

Becker, M. S.; Pollard, W. H.

2013-12-01

One of the indirect impacts of climate change on Arctic ecosystems is the expected increase of industrial development in high latitudes. The scale of terrestrial impacts cannot be known ahead of time, particularly due to a lack of long-term impact studies in this region. With one of the slowest community recovery rates of any ecosystem, the high Artic biome will be under a considerable threat that is exacerbated by a high susceptibility to change in the permafrost thermal balance. One such area that provides a suitable location for study is an old airstrip near Eureka, Ellesmere Island, Nunavut (80.0175°N, 85.7340°W). While primarily used as an ice-runway for winter transport, the airstrip endured a yearly summer removal of vegetation that continued from 1947 until its abandonment in 1951. Since then, significant vegetative and geomorphic differences between disturbed and undisturbed areas have been noted in the literature throughout the decades (Bruggemann, 1953; Beschel, 1963; Couture and Pollard, 2007), but no system wide assessment of both the ecosystem and near-surface permafrost has been conducted. Key to our study is that the greatest apparent geomorphic and vegetative changes have occurred and persisted in areas where underlying ice-wedges have been disturbed. This suggests that the colonizing communities rapidly filled new available thermokarst niches and have produced an alternative ice-wedge stable state than the surrounding polar desert. We hypothesize that disturbed areas will currently have greater depths of thaw (deeper active layers) and degraded ice-wedges, with decreased vegetation diversity but higher abundance due to a changed hydrological balance. To test this a comprehensive set of near-surface active layer and ecosystem measurements were conducted. Permafrost dynamics were characterized using probing and high-frequency Ground Penetrating Radar (500 MHz) to map the near-surface details of ice-wedges and active layer. Vegetation was measured

Exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish.

Science.gov (United States)

Letcher, Robert J; Bustnes, Jan Ove; Dietz, Rune; Jenssen, Bjørn M; Jørgensen, Even H; Sonne, Christian; Verreault, Jonathan; Vijayan, Mathilakath M; Gabrielsen, Geir W

2010-07-01

Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely

Arctic tides from GPS on sea ice

OpenAIRE

Kildegaard Rose, Stine; Skourup, Henriette; Forsberg, René

2012-01-01

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....

Phytoplankton data collected using net casts in the Arctic Ocean from the USCGC POLAR SEA from 26 July 1994 to 26 August 1994 (NODC Accession 0000770)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Phytoplankton data were collected using net casts from the USCGC POLAR SEA in the Arctic Ocean. Data were collected from 26 July 1994 to 26 August 1994. Data were...

Palynology in a polar desert, eastern North Greenland

DEFF Research Database (Denmark)

Funder, Svend Visby; Abrahamsen, Niels

1988-01-01

history back to c. 7,000 years calBP (6,000 years convBP) in this·extreme environment, which presents the coldest thermal regime where vascular plants can grow. The diagram shows that polar desert developed from sparse high arctic tundra at c. 4,300 years calBP (3,900 years convBP), owing...... to reduced summer heat. Also adjacent parts of high arctic Greenland, Canada and Svalbard suffered environmental decline, and polar deserts- presently restricted to a narrow fringe of land at the shores of the Arctic Ocean-were even more restricted before this time. Like other arctic vegetation types, polar...... desert is highly sensitive to summer temperatures, and its southern limit coincides with the isotherm for mean July temperatures of 3.5'C, A comparison with the Northwest European ice-age pollen record shows no evidence of summers as cold as those now prevailing in the extreme north, and the results...

POLAR-PALOOZA Polar Researchers and Arctic Residents Engage, Inform and Inspire Diverse Public Audiences by sharing Polar Science and Global Connections during the International Polar Year, using a New Model of Informal Science Education

Science.gov (United States)

Haines-Stiles, G.; Akuginow, E.

2006-12-01

(Please note that the POLAR-PALOOZA initiative described in this Abstract is-as of 9/7/2006-"pending" for possible support from NSF and NASA as part of this year's IPY solicitation. Subject to decisions expected by 9/30, this presentation would either be withdrawn, or amplified with specific participants, locations and dates.) Despite the success of well-regarded movies like "March of the Penguins", the polar regions remain a great unknown for most people. Public knowledge about the Arctic and Antarctic, and the critical role of the Poles in the entire Earth system, is nonexistent, incomplete or burdened with misperceptions. The International Polar Years of 2007-2009-and associated "I*Y" science years such as IHY, IYPE and eGY-present a unique opportunity to change this. The people who can best effect this change are those who know the Poles best, through living or working there. Based on innovative but proven models, POLAR-PALOOZA will use three complementary strategies to engage, inform and inspire large public audiences. (1) A national tour, under the working title "Stories from a Changing Planet", will include in-person presentations at science centers, museums, libraries and schools across North America, including Canada and Mexico. The presentations will be augmented by High Definition Video taped on location at the Poles, audio and video podcasts, and special education and outreach activities for targeted audiences. "Stories from a Changing Planet" will provide diverse audiences with an exciting opportunity to meet and interact directly with polar experts, and to appreciate why the Poles and the research done there are directly relevant to their lives. (2) The "HiDef Video Science Story Capture Corps" is a team of professional videographers, using the latest generation of low-cost, high-quality cameras, deployed to both Poles. They will document the work of multiple researchers and projects, rather than focusing on one topic for a single broadcast program

Comparative responses of phenology and reproductive development to simulated environmental change in sub-arctic and high arctic plants

Energy Technology Data Exchange (ETDEWEB)

Wookey, P A; Welker, J M; Callaghan, T V [Inst. of Terrestrial Ecology, Merlewood Research Station, Grange-over-Sands, Cumbria (United Kingdom); Parsons, A N; Potter, J A; Lee, J A; Press, M C [Dept. of Environmental Biology, Univ. of Manchester, Manchester (United Kingdom)

1993-01-01

The effects of temperature, precipitation and nutrient perturbations, and their interactions, are being assessed on two contrasting arctic ecosystems to simulate impacts of climate change. One, a high arctic polar semi-desert community, is characterized by a sparse, low and aggregated vegetation cover where plant proliferation is by seedlings, whereas the other, a sub-arctic dwarf shrub health, is characterized by a complete, vegetation cover of erect, clonal dwarf shrubs which spread vegetatively. The developmental processes of seed production were shown to be highly sensitive, even within one growing season to specific environmental perturbations which differed between sites. At the polar semi-desert site, there was a striking effect of the temperature enhancement treatments on phenology and seed-setting of Dryas octopetala ssp. octopetala, with almost no seed-setting occurring in plots experiencing ambient temperatures. By contrast, there were no significant effects of temperature enhancement alone on fruit production of Empetrum hermaphroditum at the sub-Arctic dwarf shrub heath site, although fruit production was significantly influenced by the application of nutrients and/or water. The response of dominant high arctic dwarf shrub to increased temperature suggests that any climate warming may stimulate seed-set. This could be particularly important in the high Arctic where colonization can proceed in areas dominated by bare ground and where genetic recombination may be needed to generate tolerance to predicted changes of great magnitude. In the sub-Arctic, however the closed vegetation is dominated by clonally-proliferating species. Plant fitness will increase here in response to any increased vegetative growth resulting from higher nutrient availability in warmer organic soils. (ua) (59 refs.)

PolarTREC: Successful Methods and Tools for Attaining Broad Educational Impacts with Interdisciplinary Polar Science

Science.gov (United States)

Timm, K. M.; Warburton, J.; Owens, R.; Warnick, W. K.

2008-12-01

PolarTREC--Teachers and Researchers Exploring and Collaborating, a program of the Arctic Research Consortium of the U.S. (ARCUS), is a National Science Foundation (NSF)-funded International Polar Year (IPY) project in which K-12 educators participate in hands-on field experiences in the polar regions, working closely with IPY scientists as a pathway to improving science education. Developing long-term teacher- researcher collaborations through PolarTREC ensures up-to-date climate change science content will permeate the K-12 education system long after the IPY. By infusing education with the cutting edge science from the polar regions, PolarTREC has already shown an increase in student and public knowledge of and interest in the polar regions and global climate change. Preliminary evaluations have shown that PolarTREC's program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes regarding the importance of understanding the polar regions as a person in today's world. Researchers have been overwhelmingly satisfied with PolarTREC and cited several specific strengths, including the program's crucial link between the teachers' field research experiences and their classroom and the extensive training provided to teachers prior to their expedition. This presentation will focus on other successful components of the PolarTREC program and how researchers and organizations might use these tools to reach out to the public for long-term impacts. Best practices include strategies for working with educators and the development of an internet-based platform for teachers and researchers to interact with the public, combining several communication tools such as online journals and forums, real-time Internet seminars, lesson plans, activities, audio, and other educational resources that address a broad range of scientific

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

Directory of Open Access Journals (Sweden)

Brusetti Lorenzo

2010-01-01

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

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

Science.gov (United States)

Glad, Trine; Bernhardsen, Pål; Nielsen, Kaare M; Brusetti, Lorenzo; Andersen, Magnus; Aars, Jon; Sundset, Monica A

2010-01-14

Polar bears (Ursus maritimus) are major predators in the Arctic marine ecosystem, feeding mainly on seals, and living closely associated with sea ice. Little is known of their gut microbial ecology and the main purpose of this study was to investigate the microbial diversity in faeces of polar bears in Svalbard, Norway (74-81 degrees N, 10-33 degrees E). In addition the level of blaTEM alleles, encoding ampicillin resistance (ampr) were determined. In total, ten samples were collected from ten individual bears, rectum swabs from five individuals in 2004 and faeces samples from five individuals in 2006. A 16S rRNA gene clone library was constructed, and all sequences obtained from 161 clones showed affiliation with the phylum Firmicutes, with 160 sequences identified as Clostridiales and one sequence identified as unclassified Firmicutes. The majority of the sequences (70%) were affiliated with the genus Clostridium. Aerobic heterotrophic cell counts on chocolate agar ranged between 5.0 x 10(4) to 1.6 x 10(6) colony forming units (cfu)/ml for the rectum swabs and 4.0 x 10(3) to 1.0 x 10(5) cfu/g for the faeces samples. The proportion of ampr bacteria ranged from 0% to 44%. All of 144 randomly selected ampr isolates tested positive for enzymatic beta-lactamase activity. Three % of the ampr isolates from the rectal samples yielded positive results when screened for the presence of blaTEM genes by PCR. BlaTEM alleles were also detected by PCR in two out of three total faecal DNA samples from polar bears. The bacterial diversity in faeces from polar bears in their natural environment in Svalbard is low compared to other animal species, with all obtained clones affiliating to Firmicutes. Furthermore, only low levels of blaTEM alleles were detected in contrast to their increasing prevalence in some clinical and commensal bacterial populations.

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

Science.gov (United States)

2010-01-01

Background Polar bears (Ursus maritimus) are major predators in the Arctic marine ecosystem, feeding mainly on seals, and living closely associated with sea ice. Little is known of their gut microbial ecology and the main purpose of this study was to investigate the microbial diversity in faeces of polar bears in Svalbard, Norway (74-81°N, 10-33°E). In addition the level of blaTEM alleles, encoding ampicillin resistance (ampr) were determined. In total, ten samples were collected from ten individual bears, rectum swabs from five individuals in 2004 and faeces samples from five individuals in 2006. Results A 16S rRNA gene clone library was constructed, and all sequences obtained from 161 clones showed affiliation with the phylum Firmicutes, with 160 sequences identified as Clostridiales and one sequence identified as unclassified Firmicutes. The majority of the sequences (70%) were affiliated with the genus Clostridium. Aerobic heterotrophic cell counts on chocolate agar ranged between 5.0 × 104 to 1.6 × 106 colony forming units (cfu)/ml for the rectum swabs and 4.0 × 103 to 1.0 × 105 cfu/g for the faeces samples. The proportion of ampr bacteria ranged from 0% to 44%. All of 144 randomly selected ampr isolates tested positive for enzymatic β-lactamase activity. Three % of the ampr isolates from the rectal samples yielded positive results when screened for the presence of blaTEM genes by PCR. BlaTEM alleles were also detected by PCR in two out of three total faecal DNA samples from polar bears. Conclusion The bacterial diversity in faeces from polar bears in their natural environment in Svalbard is low compared to other animal species, with all obtained clones affiliating to Firmicutes. Furthermore, only low levels of blaTEM alleles were detected in contrast to their increasing prevalence in some clinical and commensal bacterial populations. PMID:20074323

The Sensitivity of Arctic Ozone Loss to Polar Stratospheric Cloud Volume and Chlorine and Bromine Loading in a Chemistry and Transport Model

Science.gov (United States)

Douglass, A. R.; Stolarski, R. S.; Strahan, S. E.; Polansky, B. C.

2006-01-01

The sensitivity of Arctic ozone loss to polar stratospheric cloud volume (V(sub PSC)) and chlorine and bromine loading is explored using chemistry and transport models (CTMs). A simulation using multi-decadal output from a general circulation model (GCM) in the Goddard Space Flight Center (GSFC) CTM complements one recycling a single year s GCM output in the Global Modeling Initiative (GMI) CTM. Winter polar ozone loss in the GSFC CTM depends on equivalent effective stratospheric chlorine (EESC) and polar vortex characteristics (temperatures, descent, isolation, polar stratospheric cloud amount). Polar ozone loss in the GMI CTM depends only on changes in EESC as the dynamics repeat annually. The GSFC CTM simulation reproduces a linear relationship between ozone loss and Vpsc derived from observations for 1992 - 2003 which holds for EESC within approx.85% of its maximum (approx.1990 - 2020). The GMI simulation shows that ozone loss varies linearly with EESC for constant, high V(sub PSC).

Coarse mode aerosols in the High Arctic

Science.gov (United States)

Baibakov, K.; O'Neill, N. T.; Chaubey, J. P.; Saha, A.; Duck, T. J.; Eloranta, E. W.

2014-12-01

Fine mode (submicron) aerosols in the Arctic have received a fair amount of scientific attention in terms of smoke intrusions during the polar summer and Arctic haze pollution during the polar winter. Relatively little is known about coarse mode (supermicron) aerosols, notably dust, volcanic ash and sea salt. Asian dust is a regular springtime event whose optical and radiative forcing effects have been fairly well documented at the lower latitudes over North America but rarely reported for the Arctic. Volcanic ash, whose socio-economic importance has grown dramatically since the fear of its effects on aircraft engines resulted in the virtual shutdown of European civil aviation in the spring of 2010 has rarely been reported in the Arctic in spite of the likely probability that ash from Iceland and the Aleutian Islands makes its way into the Arctic and possibly the high Arctic. Little is known about Arctic sea salt aerosols and we are not aware of any literature on the optical measurement of these aerosols. In this work we present preliminary results of the combined sunphotometry-lidar analysis at two High Arctic stations in North America: PEARL (80°N, 86°W) for 2007-2011 and Barrow (71°N,156°W) for 2011-2014. The multi-years datasets were analyzed to single out potential coarse mode incursions and study their optical characteristics. In particular, CIMEL sunphotometers provided coarse mode optical depths as well as information on particle size and refractive index. Lidar measurements from High Spectral Resolution lidars (AHSRL at PEARL and NSHSRL at Barrow) yielded vertically resolved aerosol profiles and gave an indication of particle shape and size from the depolarization ratio and color ratio profiles. Additionally, we employed supplementary analyses of HYSPLIT backtrajectories, OMI aerosol index, and NAAPS (Navy Aerosol Analysis and Prediction System) outputs to study the spatial context of given events.

Synthesizing International Understanding of Changes in the Arctic Hydrological System

Science.gov (United States)

Pundsack, J. W.; Vorosmarty, C. J.; Hinzman, L. D.

2009-12-01

There are several notable gaps in our current level of understanding of Arctic hydrological systems. At the same time, rapidly emerging data sets, technologies, and modeling resources provide us with an unprecedented opportunity to move substantially forward. The Arctic Community-Wide Hydrological Analysis and Monitoring Program (Arctic-CHAMP), funded by NSF/ARCSS, was established to initiate a major effort to improve our current monitoring of water cycle variables, and to foster collaboration with the many relevant U.S. and international arctic research initiatives. These projects, funded under ARCSS through the ‘Freshwater Integration (FWI) study’, links CHAMP, the Arctic/Subarctic Ocean Fluxes (ASOF) Programme, and SEARCH. As part of the overall synthesis and integration efforts of the NSF-ARCSS Freshwater Integration (FWI) study, the program carried-out a major International Synthesis Capstone Workshop in Fall 2009 as an International Polar Year (IPY) affiliated meeting. The workshop, "Synthesizing International Understanding of Changes in the Arctic Hydrological System,” was held 30 September to 4 October 2009 in Stockholm at the Beijer Auditorium of the Royal Swedish Academy. The workshop was sponsored by the NSF-ARCSS Arctic-CHAMP Science Management Office (City College of New York / Univ. of New Hampshire), the International Study of Arctic Change (ISAC), and the International Arctic Research Center (IARC; Univ. of Alaska Fairbanks). The overarching goals of the meeting were to stage a post-IPY lessons-learned workshop with co-equal numbers of FWI, IPY, and ICARP-II researchers, using insights from recent scientific findings, data, and strategies to afford synthesis. The workshop aimed to: (1) take stock of recent advances in our understanding of changes in the Arctic hydrological system; (2) identify key remaining research gaps / unanswered questions; and (3) gather insight on where to focus future research efforts/initiatives (nationally and

Pan-Arctic distributions of continental runoff in the Arctic Ocean.

Science.gov (United States)

Fichot, Cédric G; Kaiser, Karl; Hooker, Stanford B; Amon, Rainer M W; Babin, Marcel; Bélanger, Simon; Walker, Sally A; Benner, Ronald

2013-01-01

Continental runoff is a major source of freshwater, nutrients and terrigenous material to the Arctic Ocean. As such, it influences water column stratification, light attenuation, surface heating, gas exchange, biological productivity and carbon sequestration. Increasing river discharge and thawing permafrost suggest that the impacts of continental runoff on these processes are changing. Here, a new optical proxy was developed and implemented with remote sensing to determine the first pan-Arctic distribution of terrigenous dissolved organic matter (tDOM) and continental runoff in the surface Arctic Ocean. Retrospective analyses revealed connections between the routing of North American runoff and the recent freshening of the Canada Basin, and indicated a correspondence between climate-driven changes in river discharge and tDOM inventories in the Kara Sea. By facilitating the real-time, synoptic monitoring of tDOM and freshwater runoff in surface polar waters, this novel approach will help understand the manifestations of climate change in this remote region.

Arctic air pollution: New insights from POLARCAT-IPY

International Nuclear Information System (INIS)

Law, Katharine S.; Ancellet, Gerard; Pelon, Jacques; Thomas, Jennie L.; Stohl, Andreas; Quinn, Patricia K.; Brock, Charles A.; Burkhart, John F.

2014-01-01

Given the rapid nature of climate change occurring in the Arctic and the difficulty climate models have in quantitatively reproducing observed changes such as sea ice loss, it is important to improve understanding of the processes leading to climate change in this region, including the role of short-lived climate pollutants such as aerosols and ozone. It has long been known that pollution produced from emissions at mid latitudes can be transported to the Arctic, resulting in a winter/spring aerosol maximum known as Arctic haze. However, many uncertainties remain about the composition and origin of Arctic pollution throughout the troposphere; for example, many climate-chemistry models fail to reproduce the strong seasonality of aerosol abundance observed at Arctic surface sites, the origin and deposition mechanisms of black carbon (soot) particles that darken the snow and ice surface in the Arctic is poorly understood, and chemical processes controlling the abundance of tropospheric ozone are not well quantified. The International Polar Year (IPY) Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, Climate, Chemistry, Aerosols and Transport (POLARCAT) core project had the goal to improve understanding about the origins of pollutants transported to the Arctic; to detail the chemical composition, optical properties, and climate forcing potential of Arctic aerosols; to evaluate the processes governing tropospheric ozone; and to quantify the role of boreal forest fires. This article provides a review of the many results now available based on analysis of data collected during the POLARCAT aircraft-, ship-, and ground-based field campaigns in spring and summer 2008. Major findings are highlighted and areas requiring further investigation are discussed. (authors)

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.

The 2008 Circum-Arctic Resource Appraisal

Science.gov (United States)

Moore, Thomas E.; Gautier, Donald L.

2017-11-15

Professional Paper 1824 comprises 30 chapters by various U.S. Geological Survey authors, including introduction and methodology chapters, which together provide documentation of the geological basis and methodology of the 2008 Circum-Arctic Resource Appraisal, results of which were first released in August 2008.  Twenty-eight chapters summarize the petroleum geology and resource potential of individual, geologically defined provinces north of the Arctic Circle, including those of northern Alaska, northern Canada, east and west Greenland, and most of Arctic Russia, as well as certain offshore areas of the north Atlantic Basin and the Polar Sea. Appendixes tabulate the input and output information used during the assessment.

Coordinating for Arctic Conservation: Implementing Integrated Arctic Biodiversity Monitoring, Data Management and Reporting

Science.gov (United States)

Gill, M.; Svoboda, M.

2012-12-01

Arctic ecosystems and the biodiversity they support are experiencing growing pressure from various stressors (e.g. development, climate change, contaminants, etc.) while established research and monitoring programs remain largely uncoordinated, lacking the ability to effectively monitor, understand and report on biodiversity trends at the circumpolar scale. The maintenance of healthy arctic ecosystems is a global imperative as the Arctic plays a critical role in the Earth's physical, chemical and biological balance. A coordinated and comprehensive effort for monitoring arctic ecosystems is needed to facilitate effective and timely conservation and adaptation actions. The Arctic's size and complexity represents a significant challenge towards detecting and attributing important biodiversity trends. This demands a scaled, pan-arctic, ecosystem-based approach that not only identifies trends in biodiversity, but also identifies underlying causes. It is critical that this information be made available to generate effective strategies for adapting to changes now taking place in the Arctic—a process that ultimately depends on rigorous, integrated, and efficient monitoring programs that have the power to detect change within a "management" time frame. To meet these challenges and in response to the Arctic Climate Impact Assessment's recommendation to expand and enhance arctic biodiversity monitoring, the Conservation of Arctic Flora and Fauna (CAFF) Working Group of the Arctic Council launched the Circumpolar Biodiversity Monitoring Program (CBMP). The CBMP is led by Environment Canada on behalf of Canada and the Arctic Council. The CBMP is working with over 60 global partners to expand, integrate and enhance existing arctic biodiversity research and monitoring efforts to facilitate more rapid detection, communication and response to significant trends and pressures. Towards this end, the CBMP has established three Expert Monitoring Groups representing major Arctic

NSF-supported education/outreach program takes young researchers to the Arctic

Science.gov (United States)

Alexeev, V. A.; Walsh, J. E.; Hock, R.; Kaden, U.; Euskirchen, E. S.; Kholodov, A. L.; Bret-Harte, M. S.; Sparrow, E. B.

2015-12-01

Today, more than ever, an integrated cross-disciplinary approach is necessary to explain changes in the Arctic and understand their implications for the human environment. Advanced training and active involvement of early-career scientists is an important component of this cross-disciplinary approach. This effort led by the International Arctic Research Center at the University of Alaska Fairbanks (UAF) started in 2003. The newly supported project in 2013 is planning four summer schools (one per year) focused on four themes in four different Arctic locations. It provides the participants with an interdisciplinary perspective on Arctic change and its impacts on diverse sectors of the North. It is linked to other ongoing long-term observational and educational programs (e.g. NABOS, Nansen and Amundsen Basins Observational System; LTER, Long Term Environmental Research) and targets young scientists by using the interdisciplinary and place-based setting to broaden their perspective on Arctic change and to enhance their communication skills. Each course for 15-20 people consists of classroom and hands-on components and work with a multidisciplinary group of mentors on projects devoted to themes exemplified by the location. A specialist from the School of Education at UAF evaluates student's progress during the summer schools. Lessons learned during the 12 years of conducting summer schools, methods of attracting in-kind support and approaches to teaching students are prominently featured in this study. Activities during the most recent school, conducted in Fairbanks and LTER Toolik Lake Field Station in 2015 are the focus of this presentation.

Role of polar anticyclones and mid-latitude cyclones for Arctic summertime sea-ice melting

Science.gov (United States)

Wernli, Heini; Papritz, Lukas

2018-02-01

Annual minima in Arctic sea-ice extent and volume have been decreasing rapidly since the late 1970s, with substantial interannual variability. Summers with a particularly strong reduction of Arctic sea-ice extent are characterized by anticyclonic circulation anomalies from the surface to the upper troposphere. Here, we investigate the origin of these seasonal circulation anomalies by identifying individual Arctic anticyclones (with a lifetime of typically ten days) and analysing the air mass transport into these systems. We reveal that these episodic upper-level induced Arctic anticyclones are relevant for generating seasonal circulation anomalies. Sea-ice reduction is systematically enhanced during the transient episodes with Arctic anticyclones and the seasonal reduction of sea-ice volume correlates with the area-averaged frequency of Arctic anticyclones poleward of 70° N (correlation coefficient of 0.57). A trajectory analysis shows that these anticyclones result from extratropical cyclones injecting extratropical air masses with low potential vorticity into the Arctic upper troposphere. Our results emphasize the fundamental role of extratropical cyclones and associated diabatic processes in establishing Arctic anticyclones and, in turn, seasonal circulation anomalies, which are of key importance for understanding the variability of summertime Arctic sea-ice melting.

Tourism and Arctic Observation Systems: exploring the relationships

Directory of Open Access Journals (Sweden)

Suzanne de la Barre

2016-03-01

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

The BNL polarized H- ion source development program

International Nuclear Information System (INIS)

Kponou, A.; Alessi, J.; Hershcovitch, A.; DeVito, B.

1992-01-01

Polarized protons have been available for acceleration in the AGS for the high energy physics program since 1984. The polarized H - source, PONI-1, has routinely supplied a 0.4 Hz, 400 μsec pulse having a nominal intensity of 40 μA. Polarization is ∼80% out of the ion source. After PONI- 1 became operational, a program was initiated to develop a more intense source based on a cold ground state atomic beam source, followed by ionization of the polarized H degrees beam by D - charge exchange. Various phases of this work have been fully reported elsewhere, and only a summary is given here

Arctic Risk Management (ARMNet) Network: Linking Risk Management Practitioners and Researchers Across the Arctic Regions of Canada and Alaska To Improve Risk, Emergency and Disaster Preparedness and Mitigation Through Comparative Analysis and Applied Research

Science.gov (United States)

Garland, A.

2015-12-01

The Arctic Risk Management Network (ARMNet) was conceived as a trans-disciplinary hub to encourage and facilitate greater cooperation, communication and exchange among American and Canadian academics and practitioners actively engaged in the research, management and mitigation of risks, emergencies and disasters in the Arctic regions. Its aim is to assist regional decision-makers through the sharing of applied research and best practices and to support greater inter-operability and bilateral collaboration through improved networking, joint exercises, workshops, teleconferences, radio programs, and virtual communications (eg. webinars). Most importantly, ARMNet is a clearinghouse for all information related to the management of the frequent hazards of Arctic climate and geography in North America, including new and emerging challenges arising from climate change, increased maritime polar traffic and expanding economic development in the region. ARMNet is an outcome of the Arctic Observing Network (AON) for Long Term Observations, Governance, and Management Discussions, www.arcus.org/search-program. The AON goals continue with CRIOS (www.ariesnonprofit.com/ARIESprojects.php) and coastal erosion research (www.ariesnonprofit.com/webinarCoastalErosion.php) led by the North Slope Borough Risk Management Office with assistance from ARIES (Applied Research in Environmental Sciences Nonprofit, Inc.). The constituency for ARMNet will include all northern academics and researchers, Arctic-based corporations, First Responders (FRs), Emergency Management Offices (EMOs) and Risk Management Offices (RMOs), military, Coast Guard, northern police forces, Search and Rescue (SAR) associations, boroughs, territories and communities throughout the Arctic. This presentation will be of interest to all those engaged in Arctic affairs, describe the genesis of ARMNet and present the results of stakeholder meetings and webinars designed to guide the next stages of the Project.

Population genomics reveal recent speciation and rapid evolutionary adaptation in polar bears

DEFF Research Database (Denmark)

Liu, Shiping; Lorenzen, Eline; Fumagalli, Matteo

2014-01-01

Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyperlipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and sho...

The Polar Crust Project- BSC Diversity and Variability in the Arctic and Antarctica

Science.gov (United States)

Williams, Laura; Borchhardt, Nadine; Komisc-Buchmann, Karin; Becker, Burkhard; Karsten, Ulf; Büdel, Burkhard

2015-04-01

The Polar Crust Project is a newly funded DFG initiative that aims to provide a precise evaluation of the biodiversity of eukaryotic green microalgae and cyanobacteria in Biological Soil Crusts (BSC) isolated from the Antarctic Peninsula and Arctic Svalbard. This project will include a thorough investigation into the composition of BSC in the Polar regions, this especially is important for Svalbard due to the severe lack of any previous research on such communities in this area. During our expedition to Spitsbergen, Svalbard in August 2014 we were particularly surprised to find that the coverage of BSC is extremely high and is certainly the dominant vegetation type around Ny Ålesund. Due to this discovery the project has now been extended to include long term measurements of CO2 gas exchange in order to gain exact seasonal carbon fixation rates and therefore discovering how the BSC contributes to the ecosystems carbon balance. The research areas of Spitsbergen were centred around 2 localities: Ny-Ålesund is a research town, home to the AWIPEV station, on the Brøgger peninsula. Longyearbyen, which is the largest settlement on the island, is found in the valley Longyeardalen on the shore of Adventfjorden. Areas where BSC is the prevalent vegetation type were identified, 6 around Ny-Ålesund and 4 for Longyearbyen, and vegetation surveys were conducted. This entailed 625 single point measurements at each site and identifying the crust/or other cover type. For example, green algal lichen, cyanobacterial crust, higher plant, open soil. Samples were also taken at every location in order to study the green algal and cyanobacterial diversity. The vegetation survey will allow us to get a good overview of the BSC composition at the different sites. In January 2015 an expedition to the Antarctic Peninsular took place, here the sampling method was repeated and therefore both Polar Regions BSC composition can be described and compared. Here, we wish to introduce the Polar

AURORA BOREALIS: a polar-dedicated European Research Platform

Science.gov (United States)

Wolff-Boenisch, Bonnie; Egerton, Paul; Thiede, Joern; Roberto, Azzolini; Lembke-Jene, Lester

2010-05-01

Polar research and in particular the properties of northern and southern high latitude oceans are currently a subject of intense scientific debate and investigations, because they are subject to rapid and dramatic climatic variations. Polar regions react more rapidly and intensively to global change than other regions of the earth. A shrinking of the Arctic sea-ice cover, potentially leading to an opening of sea passages to the north of North America and Eurasia, on the long to a "blue" Arctic Ocean would additionally have a strong impact on transport, commerce and tourism bearing potential risk for humans and complex ecosystems in the future. In spite of their critical role processes and feedbacks, especially in winter but not exclusively, are virtually unknown: The Arctic Ocean for example, it is the only basin of the world's oceans that has essentially not been sampled by the drill ships of the Deep-Sea Drilling Project (DSDP) or the Ocean Drilling Program (ODP) and its long-term environmental history and tectonic structure is therefore poorly known. Exceptions are the ODP Leg 151 and the more recent very successful ACEX-expedition of the Integrated Ocean Drilling Program (IODP) in 2004. To help to address the most pressing questions regarding climate change and related processes, a Pan-European initiative in the field of Earth system science has been put in place: AURORA BOREALIS is the largest environmental research infrastructure on the ESFRI roadmap of the European Community. AURORA BOREALIS is a very powerful research icebreaker, which will enable year-round operations in the Arctic and the Antarctic as well as in the adjacent ocean basins. Equipped with its drilling rig, the vessel is also capable to explore the presently completely unknown Arctic deep-sea floor. Last but not least, the ship is a floating observatory and mobile monitoring platform that permits to measure on a long-term basis comprehensive time series in all research fields relevant to

The University of Delaware Carlson International Polar Year Events: Collaborative and Educational Outreach

Science.gov (United States)

Nelson, F. E.; Bryant, T.; Wellington, P.; Dooley, J.; Bird, M.

2008-12-01

Delaware is a small state with, by virtue of its coastal location, a large stake in climatic change in the polar regions. The University of Delaware has maintained a strong presence in cold-regions research since the mid-1940s, when William Samuel Carlson, a highly accomplished Arctic explorer, military strategist, and earth scientist, was named 20th President (1946-50) of the University. Carlson played a leading role in two of the University of Michigan's Greenland expeditions in the late 1920s and early 1930s. As Director of the Arctic, Desert, and Tropic Branch of the US Army Air Forces Tactical Center during World War II, Colonel Carlson played a role in developing several air transportation routes through the Arctic that helped to facilitate the Allied victory in Europe. Carlson authored many scientific and popular publications concerned with the Arctic, including the books Greenland Lies North (1940) and Lifelines Through the Arctic (1962). Although the University of Delaware has maintained a vigorous and continuous program of polar research since Carlson's tenure, the faculty, staff, and students involved are diffused throughout the University's colleges and departments, without an institutional focal point. Consequently, although many of these individuals are well known in their respective fields, the institution has not until recently been perceived widely as a center of polar-oriented research. The goals of the Carlson International Polar Year Events are to: (a) develop a sense of community among UD's diffuse polar-oriented researchers and educators; (b) create a distinctive and highly visible role for UD in the milieu of IPY activities; (c) promote interest in and knowledge about the polar regions in the State of Delaware, at all educational levels; (d) forge a close relationship between UD and the American Geographical Society, a national organization involved closely with previous International Polar Years; and (e) create a new basis for development

Internet Blogs, Polar Bears, and Climate-Change Denial by Proxy.

Science.gov (United States)

Harvey, Jeffrey A; van den Berg, Daphne; Ellers, Jacintha; Kampen, Remko; Crowther, Thomas W; Roessingh, Peter; Verheggen, Bart; Nuijten, Rascha J M; Post, Eric; Lewandowsky, Stephan; Stirling, Ian; Balgopal, Meena; Amstrup, Steven C; Mann, Michael E

2018-04-01

Increasing surface temperatures, Arctic sea-ice loss, and other evidence of anthropogenic global warming (AGW) are acknowledged by every major scientific organization in the world. However, there is a wide gap between this broad scientific consensus and public opinion. Internet blogs have strongly contributed to this consensus gap by fomenting misunderstandings of AGW causes and consequences. Polar bears (Ursus maritimus) have become a "poster species" for AGW, making them a target of those denying AGW evidence. Here, focusing on Arctic sea ice and polar bears, we show that blogs that deny or downplay AGW disregard the overwhelming scientific evidence of Arctic sea-ice loss and polar bear vulnerability. By denying the impacts of AGW on polar bears, bloggers aim to cast doubt on other established ecological consequences of AGW, aggravating the consensus gap. To counter misinformation and reduce this gap, scientists should directly engage the public in the media and blogosphere.

Leveraging scientific credibility about Arctic sea ice trends in a polarized political environment.

Science.gov (United States)

Jamieson, Kathleen Hall; Hardy, Bruce W

2014-09-16

This work argues that, in a polarized environment, scientists can minimize the likelihood that the audience's biased processing will lead to rejection of their message if they not only eschew advocacy but also, convey that they are sharers of knowledge faithful to science's way of knowing and respectful of the audience's intelligence; the sources on which they rely are well-regarded by both conservatives and liberals; and the message explains how the scientist arrived at the offered conclusion, is conveyed in a visual form that involves the audience in drawing its own conclusions, and capsulizes key inferences in an illustrative analogy. A pilot experiment raises the possibility that such a leveraging-involving-visualizing-analogizing message structure can increase acceptance of the scientific claims about the downward cross-decade trend in Arctic sea ice extent and elicit inferences consistent with the scientific consensus on climate change among conservatives exposed to misleadingly selective data in a partisan news source.

A consistent definition of the Arctic polar vortex breakup in both the lower and upper stratosphere

Science.gov (United States)

Choi, W.; Seo, J.

2014-12-01

Breakup of the polar vortex is a dominant feature of the seasonal transition from winter to summer in the stratosphere, which significantly affects stratospheric O3 concentration and tropospheric weather. Previously several criteria for the vortex breakup have been suggested based on the potential vorticity (PV) and wind speed, however, those mainly have focused on the lower stratospheric vortex of which spatiotemporal evolution and decay are more continuous than those of the upper stratospheric vortex. To find a consistent criterion for the vortex breakup in both the lower and upper stratosphere, the present study defined a polar vortex breakup day as when PV gradient at the polar vortex edge becomes lower than that at the subtropical edge on the area equivalent latitude based on PV. With applying the new definition to the UK Met Office reanalysis data, the breakup days of the Arctic polar vortices on 18 isentropic levels from 450 K to 1300 K were calculated for the period of 1993-2005. In comparison with CH4, N2O and O3 measured by the ILAS and POAM II/III satellite instruments, the breakup days are well consistent with changes in the distribution of such tracers as well as their zonal standard deviations associated with the vortex structure breaking and irreversible mixing. The vortex breakup in the upper stratosphere occurs more or less a month prior to that in the middle and lower stratosphere while the stratospheric final warming events occurs simultaneously in the upper and lower stratosphere.

Thermal Thresholds of Phytoplankton Growth in Polar Waters and Their Consequences for a Warming Polar Ocean

KAUST Repository

Coello-Camba, Alexandra

2017-06-02

Polar areas are experiencing the steepest warming rates on Earth, a trend expected to continue in the future. In these habitats, phytoplankton communities constitute the basis of the food web and their thermal tolerance may dictate how warming affects these delicate environments. Here, we compiled available data on thermal responses of phytoplankton growth in polar waters. We assembled 53 growth-vs.-temperature curves (25 from the Arctic, 28 from the Southern oceans), indicating the limited information available for these ecosystems. Half of the data from Arctic phytoplankton came from natural communities where low ambient concentrations could limit growth rates. Phytoplankton from polar waters grew faster under small temperature increases until reaching an optimum (TOPT), and slowed when temperatures increased beyond this value. This left-skewed curves were characterized by higher activation energies (Ea) for phytoplankton growth above than below the TOPT. Combining these thermal responses we obtained a community TOPT of 6.5°C (±0.2) and 5.2°C (±0.1) for Arctic and Southern Ocean phytoplankton communities, respectively. These threshold temperatures were already exceeded at 70°N during the first half of August 2013, evidenced by sea surface temperatures (SSTs, satellite data, http://www.ncdc.noaa.gov). We forecasted SSTs for the end of the twenty-first century by assuming an overall 3°C increase, equivalent to a low emission scenario. Our forecasts show that SSTs at 70°N are expected to exceed TOPT during summer by 2100, and during the first half of August at 75°N. While recent Arctic spring temperatures average 0.5°C and −0.7°C at 70°N and 75°N, respectively, they could increase to 2.8°C at 70°N and 2.2°C at 75°N as we approach 2100. Such temperature increases could lead to intense phytoplankton blooms, shortened by fast nutrient consumption. As SSTs increase, thermal thresholds for phytoplankton growth would be eventually exceeded during bloom

Thermal Thresholds of Phytoplankton Growth in Polar Waters and Their Consequences for a Warming Polar Ocean

Directory of Open Access Journals (Sweden)

Alexandra Coello-Camba

2017-06-01

Full Text Available Polar areas are experiencing the steepest warming rates on Earth, a trend expected to continue in the future. In these habitats, phytoplankton communities constitute the basis of the food web and their thermal tolerance may dictate how warming affects these delicate environments. Here, we compiled available data on thermal responses of phytoplankton growth in polar waters. We assembled 53 growth-vs.-temperature curves (25 from the Arctic, 28 from the Southern oceans, indicating the limited information available for these ecosystems. Half of the data from Arctic phytoplankton came from natural communities where low ambient concentrations could limit growth rates. Phytoplankton from polar waters grew faster under small temperature increases until reaching an optimum (TOPT, and slowed when temperatures increased beyond this value. This left-skewed curves were characterized by higher activation energies (Ea for phytoplankton growth above than below the TOPT. Combining these thermal responses we obtained a community TOPT of 6.5°C (±0.2 and 5.2°C (±0.1 for Arctic and Southern Ocean phytoplankton communities, respectively. These threshold temperatures were already exceeded at 70°N during the first half of August 2013, evidenced by sea surface temperatures (SSTs, satellite data, http://www.ncdc.noaa.gov. We forecasted SSTs for the end of the twenty-first century by assuming an overall 3°C increase, equivalent to a low emission scenario. Our forecasts show that SSTs at 70°N are expected to exceed TOPT during summer by 2100, and during the first half of August at 75°N. While recent Arctic spring temperatures average 0.5°C and −0.7°C at 70°N and 75°N, respectively, they could increase to 2.8°C at 70°N and 2.2°C at 75°N as we approach 2100. Such temperature increases could lead to intense phytoplankton blooms, shortened by fast nutrient consumption. As SSTs increase, thermal thresholds for phytoplankton growth would be eventually exceeded

Thermal Thresholds of Phytoplankton Growth in Polar Waters and Their Consequences for a Warming Polar Ocean

KAUST Repository

Coello-Camba, Alexandra; Agusti, Susana

2017-01-01

Polar areas are experiencing the steepest warming rates on Earth, a trend expected to continue in the future. In these habitats, phytoplankton communities constitute the basis of the food web and their thermal tolerance may dictate how warming affects these delicate environments. Here, we compiled available data on thermal responses of phytoplankton growth in polar waters. We assembled 53 growth-vs.-temperature curves (25 from the Arctic, 28 from the Southern oceans), indicating the limited information available for these ecosystems. Half of the data from Arctic phytoplankton came from natural communities where low ambient concentrations could limit growth rates. Phytoplankton from polar waters grew faster under small temperature increases until reaching an optimum (TOPT), and slowed when temperatures increased beyond this value. This left-skewed curves were characterized by higher activation energies (Ea) for phytoplankton growth above than below the TOPT. Combining these thermal responses we obtained a community TOPT of 6.5°C (±0.2) and 5.2°C (±0.1) for Arctic and Southern Ocean phytoplankton communities, respectively. These threshold temperatures were already exceeded at 70°N during the first half of August 2013, evidenced by sea surface temperatures (SSTs, satellite data, http://www.ncdc.noaa.gov). We forecasted SSTs for the end of the twenty-first century by assuming an overall 3°C increase, equivalent to a low emission scenario. Our forecasts show that SSTs at 70°N are expected to exceed TOPT during summer by 2100, and during the first half of August at 75°N. While recent Arctic spring temperatures average 0.5°C and −0.7°C at 70°N and 75°N, respectively, they could increase to 2.8°C at 70°N and 2.2°C at 75°N as we approach 2100. Such temperature increases could lead to intense phytoplankton blooms, shortened by fast nutrient consumption. As SSTs increase, thermal thresholds for phytoplankton growth would be eventually exceeded during bloom

Disparities in Arctic Health

Centers for Disease Control (CDC) Podcasts

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.

Recent dynamics of arctic and sub-arctic vegetation

International Nuclear Information System (INIS)

Epstein, Howard E; Myers-Smith, Isla; Walker, Donald A

2013-01-01

We present a focus issue of Environmental Research Letters on the ‘Recent dynamics of arctic and sub-arctic vegetation’. The focus issue includes three perspective articles (Verbyla 2011 Environ. Res. Lett. 6 041003, Williams et al 2011 Environ. Res. Lett. 6 041004, Loranty and Goetz 2012 Environ. Res. Lett. 7 011005) and 22 research articles. The focus issue arose as a result of heightened interest in the response of high-latitude vegetation to natural and anthropogenic changes in climate and disturbance regimes, and the consequences that these vegetation changes might have for northern ecosystems. A special session at the December 2010 American Geophysical Union Meeting on the ‘Greening of the Arctic’ spurred the call for papers. Many of the resulting articles stem from intensive research efforts stimulated by International Polar Year projects and the growing acknowledgment of ongoing climate change impacts in northern terrestrial ecosystems. (synthesis and review)

Changing Arctic: A Strategic Analysis of United States Arctic Policy and the United Nations Convention on the Law of the Sea

Science.gov (United States)

2013-05-01

is below the constellation Ursa Minor, or the Great Bear . Hence, the word Arctic comes from the Greek word arktos or “ bear .” 7 The generally...13 David Curtis Wright , Canadian Defence and Foreign Affairs Institute., and Canadian Electronic Library (Firm), "The Panda ... Bear Readies to Meet the Polar Bear China and Canada’s Arctic Sovereignty Challenge," Canadian Defence & Foreign Affairs Institute, p. 4 67

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...

Climate Change and Arctic Issues in the Marine and Environmental Science Curriculum at the U.S. Coast Guard Academy

Science.gov (United States)

Vlietstra, L.; McConnell, M. C.; Bergondo, D. L.; Mrakovcich, K. L.; Futch, V.; Stutzman, B. S.; Fleischmann, C. M.

2016-02-01

As global climate change becomes more evident, demand will likely increase for experts with a detailed understanding of the scientific basis of climate change, the ocean's role in the earth-atmosphere system, and forecasted impacts, especially in Arctic regions where effects may be most pronounced. As a result, programs in marine and environmental sciences are uniquely poised to prepare graduates for the formidable challenges posed by changing climates. Here we present research evaluating the prevalence and themes of courses focusing on anthropogenic climate change in 125 Marine Science and Environmental Science undergraduate programs at 86 institutions in the United States. These results, in addition to the increasing role of the Coast Guard in the Arctic, led to the development of two new courses in the curriculum. Climate Change Science, a one-credit seminar, includes several student-centered activities supporting key learning objectives. Polar Oceanography, a three-credit course, incorporates a major outreach component to Coast Guard units and members of the scientific community. Given the importance of climate change in Arctic regions in particular, we also propose six essential "Arctic Literacy Principles" around which courses or individual lesson plans may be organized. We show how these principles are incorporated into an additional new three-credit course, Model Arctic Council, which prepares students to participate in a week-long simulation exercise of Arctic Council meetings, held in Fairbanks, Alaska. Students examine the history and mission of the Arctic Council and explore some of the issues on which the council has deliberated. Special attention is paid to priorities of the current U.S. chairmanship of the Arctic Council which include climate change impacts on, and stewardship of, the Arctic Ocean.

The Arctic Vegetation Type Change retrieved from Spaceborne Observations and its Influence on the Simulation of Permafrost Thawing

Science.gov (United States)

Kim, Y.; Wang, Z.

2017-12-01

The vegetation types change in Arctic has been studied using 10 years of MODIS land cover product (MCD12Q1). The shrub expansion is observed in Alaska and Northeast Asia, while shrub fraction decreases in North Canada and Southwest Arctic Eurasia. The total Arctic shrub fraction increases 3% in 10 years. The tundra decreases where the shrub expands, and thrives where the shrub retreats. In order to isolate the influence of the vegetation dynamic on the permafrost thawing, the Arctic terrestrial ecosystem in recent decades will be simulated using the Community Land Model (CLM) with and without the vegetation type changes. The energy and carbon exchange on the land surface will also be simulated and compared. Acknowledgement: This work was supported by the Korea Polar Research Institute (KOPRI, PN17081) and the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (2015R1C1A2A01054800).

Constraining estimates of methane emissions from Arctic permafrost regions with CARVE

Science.gov (United States)

Chang, R. Y.; Karion, A.; Sweeney, C.; Henderson, J.; Mountain, M.; Eluszkiewicz, J.; Luus, K. A.; Lin, J. C.; Dinardo, S.; Miller, C. E.; Wofsy, S. C.

2013-12-01

Permafrost in the Arctic contains large carbon pools that are currently non-labile, but can be released to the atmosphere as polar regions warm. In order to predict future climate scenarios, we need to understand the emissions of these greenhouse gases under varying environmental conditions. This study presents in-situ measurements of methane made on board an aircraft during the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), which sampled over the permafrost regions of Alaska. Using measurements from May to September 2012, seasonal emission rate estimates of methane from tundra are constrained using the Stochastic Time-Inverted Lagrangian Transport model, a Lagrangian particle dispersion model driven by custom polar-WRF fields. Preliminary results suggest that methane emission rates have not greatly increased since the Arctic Boundary Layer Experiment conducted in southwest Alaska in 1988.

Protecting polar wilderness : Just a western philosophical idea or a useful concept for regulating human activities in the polar regions?

NARCIS (Netherlands)

Bastmeijer, Kees; Leary, D.; Koivurova, T.; Alfredsson, G.

2009-01-01

Governments involved in Arctic and Antarctic governance have been well aware of the increasing human pressure on the Polar Regions and particularly the last two decades many initiatives have been taken to protect the Arctic and Antarctic environment. But what values are to be protected? This paper

Carbon dioxide in Arctic and subarctic regions

Energy Technology Data Exchange (ETDEWEB)

Gosink, T. A.; Kelley, J. J.

1981-03-01

A three year research project was presented that would define the role of the Arctic ocean, sea ice, tundra, taiga, high latitude ponds and lakes and polar anthropogenic activity on the carbon dioxide content of the atmosphere. Due to the large physical and geographical differences between the two polar regions, a comparison of CO/sub 2/ source and sink strengths of the two areas was proposed. Research opportunities during the first year, particularly those aboard the Swedish icebreaker, YMER, provided additional confirmatory data about the natural source and sink strengths for carbon dioxide in the Arctic regions. As a result, the hypothesis that these natural sources and sinks are strong enough to significantly affect global atmospheric carbon dioxide levels is considerably strengthened. Based on the available data we calculate that the whole Arctic region is a net annual sink for about 1.1 x 10/sup 15/ g of CO/sub 2/, or the equivalent of about 5% of the annual anthropogenic input into the atmosphere. For the second year of this research effort, research on the seasonal sources and sinks of CO/sub 2/ in the Arctic will be continued. Particular attention will be paid to the seasonal sea ice zones during the freeze and thaw periods, and the tundra-taiga regions, also during the freeze and thaw periods.

Arctic Warming as News - Perils and Possibilities

Science.gov (United States)

Revkin, A. C.

2015-12-01

A science journalist in his 30th year covering human-driven climate change, including on three Arctic reporting trips, reflects on successes and setbacks as news media, environmentalists and Arctic communities have tried to convey the significance of polar change to a public for which the ends of the Earth will always largely be a place of the imagination.Novel challenges are arising in the 24/7 online media environment, as when a paper by a veteran climate scientist proposing a mechanism for abrupt sea-level rise became a big news story before it was accepted by the open-review journal to which it had been submitted. New science is digging in on possible connections between changing Arctic sea ice and snow conditions and disruptive winter weather in more temperate northern latitudes, offering a potential link between this distant region and the lives of ordinary citizens. As cutting-edge research, such work gets substantial media attention. But, as with all new areas of inquiry, uncertainty dominates - creating the potential for distracting the public and policymakers from the many aspects of anthropogenic climate change that are firmly established - but, in a way, boring because of that.With the challenges, there are unprecedented opportunities for conveying Arctic science. In some cases, researchers on expeditions are partnering with media, offering both scientists and news outlets fresh ways to convey the story of Arctic change in an era of resource constraints.Innovative uses of crittercams, webcams, and satellite observations offer educators and interested citizens a way to track and appreciate Arctic change. But more can be done to engage the public directly without the news media as an intermediary, particularly if polar scientists or their institutions test some of the established practices honed by more experienced communicators at NASA.

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

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 o......-gauges and altimetry data. Furthermore, we prove that the geodetic reference ellipsoid WGS84, can be interpolated to the tidal defined zero level by applying geophysical corrections to the GPS data....

The Arctic : the great breakup; Arctique : la grande debacle

Energy Technology Data Exchange (ETDEWEB)

Lemieux, R.

2007-05-15

The impact that climate change has had on the famous Northwest passage in Canada's Arctic was discussed. The water channel through the Arctic Islands is now navigable during the summer and it has been predicted that in 40 years, it may be navigable throughout the entire year. Although the Arctic is still covered with snow, the icebergs which navigators have feared no longer exist. Environment Canada has cautioned that Canada's extreme north would be most at risk from global warming, with temperatures increasing by 6 degrees, or 3 times higher than in moderate zones. The joint Canadian-United States program Surface Heat Budget of the Arctic has also confirmed that the waters of the Beaufort Sea are less salty and relatively warmer. Climatologists also project that the predicted increase in snowfall will act as an insulation blanket, thereby preventing the ice from thickening. Scientists stated that the gigantic polar cap, which has been frozen for the past 3.2 million years, will have fissures everywhere by 2080. The Northwest passage will become easily accessible in less than 10 years. This article raised questions regarding the role of the Northwest passage as an international maritime route. It presented the case of the first successful passage of a U.S. commercial oil tanker in 1969 which created controversy regarding Canada's territorial waters. Fourty years later, this issue is still not resolved. The article questioned whether there should be more cooperation on both the Canadian and American sides in light of the shared common interests such as commerce, science and security. It was noted that although Canada has sovereignty of the Arctic Islands, there are eight other countries who share the Arctic. 4 figs.

Videographic Education: Owning the Polar Crisis

Science.gov (United States)

Vachon, R. W.; Buhr, S. M.

2007-12-01

Television and internet-served video is an increasingly important media tool for reaching into society. This talk will present clips from a film designed to educate the public about warming in the polar regions, the socioeconomic and environmental implications of this warming; and the actions we can take to slow down human contributions to climate change. This talk will present a short film Owning the Polar Crisis, which is drawn from footage for Polar Visions, a four segment film available for educational audiences and the public.. The films are unique in that they draw from the perspectives of well-known climate scientists, citizens from all over the planet and natives of the Arctic. The compelling images were taken from numerous locations around the Arctic, including Alaska and Greenland. Owning the Polar Crisis was filmed, directed and produced by Dr. Ryan Vachon, a climate scientist and videographer with an intimate knowledge of the subject matter.

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......, 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...

Foreword to the thematic cluster: the Arctic in Rapid Transition—marine ecosystems

Directory of Open Access Journals (Sweden)

Monika Kędra

2015-12-01

Full Text Available The Arctic is warming and losing sea ice. Happening at a much faster rate than previously expected, these changes are causing multiple ecosystem feedbacks in the Arctic Ocean. The Arctic in Rapid Transition (ART initiative was developed by early-career scientists as an integrative, international, multidisciplinary, long-term pan-Arctic network to study changes and feedbacks among the physical and biogeochemical components of the Arctic Ocean and their ultimate impacts on biological productivity on different timescales. In 2012, ART jointly organized with the Association of Polar Early Career Scientists their second science workshop—Overcoming Challenges of Observation to Model Integration in Marine Ecosystem Response to Sea Ice Transitions—at the Institute of Oceanology, Polish Academy of Sciences, in Sopot. This workshop aimed to identify linkages and feedbacks between atmosphere–ice–ocean forcing and biogeochemical processes, which are critical for ecosystem function, land–ocean interactions and productive capacity of the Arctic Ocean. This special thematic cluster of Polar Research brings together seven papers that grew out of workgroup discussions. Papers examine the climate change impacts on various ecosystem elements, providing important insights on the marine ecological and biogeochemical processes on various timescales. They also highlight priority areas for future research.

Arctic Riverine CDOM and its effects on the Polar Marine Light Field

Energy Technology Data Exchange (ETDEWEB)

Orandle, Zoe Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Weijer, Wilbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Elliott, Scott M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wang, Shanlin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-09-28

It is well-known that CDOM (Chromophoric Dissolved Organic Matter) can have a significant effect on biological activity in the photic zones of aquatic ecosystems. However, the extent of CDOM’s interference with biological activity is not well-known. We examined this issue in great detail in the mixed surface layer of the Arctic Ocean. We studied the impacts of CDOM’s light attenuation on Arctic phytoplankton populations to discover if riverine CDOM’s presence in the Arctic ocean could inhibit and possibly prevent local phytoplankton populations from performing photosynthesis. We incorporated biogeochemistry concepts and data with oceanographic models and calculations to approach the problem. The results showed that riverine CDOM can indeed significantly impact the productivity of phytoplankton populations during the spring and summer months near the major Arctic river mouths we chose to examine. Although our study was detailed and inclusive of many variables, the issue of CDOM’s light attenuation and its effects on phytoplankton populations must be explored on a global scale to help understand if riverine CDOM could prove disastrous for phytoplankton populations.

Towards an International Polar Data Coordination Network

Directory of Open Access Journals (Sweden)

P L Pulsifer

2014-10-01

Full Text Available Data management is integral to sound polar science. Through analysis of documents reporting on meetings of the Arctic data management community, a set of priorities and strategies are identified. These include the need to improve data sharing, make use of existing resources, and better engage stakeholders. Network theory is applied to a preliminary inventory of polar and global data management actors to improve understanding of the emerging community of practice. Under the name the Arctic Data Coordination Network, we propose a model network that can support the community in achieving their goals through improving connectivity between existing actors.

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.

Immune function in arctic mammals

DEFF Research Database (Denmark)

Desforges, Jean-Pierre; Jasperse, Lindsay; Jensen, Trine Hammer

2018-01-01

Natural killer (NK) cells are a vital part of the rapid and non-specific immune defense against invading pathogens and tumor cells. This study evaluated NK cell-like activity by flow cytometry for the first time in three ecologically and culturally important Arctic mammal species: polar bear (Ursus...... the effector:target cell ratio increased. Comparing NK activity between fresh and cryopreserved mouse lymphocytes revealed little to no difference in function, highlighting the applicability of cryopreserving cells in field studies. The evaluation of this important innate immune function in Arctic mammals can...... contribute to future population health assessments, especially as pollution-induced suppression of immune function may increase infectious disease susceptibility....

Using fluorescent dissolved organic matter to trace and distinguish the origin of Arctic surface waters

Science.gov (United States)

Gonçalves-Araujo, Rafael; Granskog, Mats A.; Bracher, Astrid; Azetsu-Scott, Kumiko; Dodd, Paul A.; Stedmon, Colin A.

2016-01-01

Climate change affects the Arctic with regards to permafrost thaw, sea-ice melt, alterations to the freshwater budget and increased export of terrestrial material to the Arctic Ocean. The Fram and Davis Straits represent the major gateways connecting the Arctic and Atlantic. Oceanographic surveys were performed in the Fram and Davis Straits, and on the east Greenland Shelf (EGS), in late summer 2012/2013. Meteoric (fmw), sea-ice melt, Atlantic and Pacific water fractions were determined and the fluorescence properties of dissolved organic matter (FDOM) were characterized. In Fram Strait and EGS, a robust correlation between visible wavelength fluorescence and fmw was apparent, suggesting it as a reliable tracer of polar waters. However, a pattern was observed which linked the organic matter characteristics to the origin of polar waters. At depth in Davis Strait, visible wavelength FDOM was correlated to apparent oxygen utilization (AOU) and traced deep-water DOM turnover. In surface waters FDOM characteristics could distinguish between surface waters from eastern (Atlantic + modified polar waters) and western (Canada-basin polar waters) Arctic sectors. The findings highlight the potential of designing in situ multi-channel DOM fluorometers to trace the freshwater origins and decipher water mass mixing dynamics in the region without laborious samples analyses. PMID:27667721

75 FR 17763 - Arctic National Wildlife Refuge, Fairbanks, AK

Science.gov (United States)

2010-04-07

... diversity, including, but not limited to, the Porcupine caribou herd (including participation in coordinated ecological studies and management of this herd and the Western Arctic caribou herd), polar bears, grizzly...

Arctic Tides from GPS on sea-ice

DEFF Research Database (Denmark)

Kildegaard Rose, Stine; Skourup, Henriette; Forsberg, René

2013-01-01

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 perform less accurately in the polar regions. This paper presents, a kinematic processing of global positioning system (GPS....... The results show coherence between the GPS buoy measurements, and the tide model. Furthermore, we have proved that the reference ellipsoid of WGS84, can be interpolated to the tidal defined zero level by applying geophysical corrections to the GPS data....

Organochlorine contaminant and stable isotope profiles in Arctic fox (Alopex lagopus) from the Alaskan and Canadian Arctic

Energy Technology Data Exchange (ETDEWEB)

Hoekstra, P.F.; Braune, B.M.; O' Hara, T.M.; Elkin, B.; Solomon, K.R.; Muir, D.C.G

2003-04-01

PCBs in Arctic fox are lower than reported in other Arctic populations and unlikely to cause significant impairment of reproductive success. - Arctic fox (Alopex lagopus) is a circumpolar species distributed across northern Canada and Alaska. Arctic fox muscle and liver were collected at Barrow, AK, USA (n=18), Holman, NT, Canada (n=20), and Arviat, NU, Canada (n=20) to elucidate the feeding ecology of this species and relate these findings to body residue patterns of organochlorine contaminants (OCs). Stable carbon ({delta}{sup 13}C) and nitrogen ({delta}{sup 15}N) isotope analyses of Arctic fox muscle indicated that trophic position (estimated by {delta}{sup 15}N) is positively correlated with increasing {delta}{sup 13}C values, suggesting that Arctic fox with a predominately marine-based foraging strategy occupy a higher trophic level than individuals mostly feeding from a terrestrial-based carbon source. At all sites, the rank order for OC groups in muscle was polychlorinated biphenyls ({sigma}PCB) > chlordane-related compounds ({sigma}CHLOR) > hexachlorocyclohexane ({sigma}HCH) > total toxaphene (TOX) {>=}chlorobenzenes ({sigma}ClBz) > DDT-related isomers ({sigma}DDT). In liver, {sigma}CHLOR was the most abundant OC group, followed by {sigma}PCB > TOX > {sigma}HCH > {sigma}ClBz > {sigma}DDT. The most abundant OC analytes detected from Arctic fox muscle and liver were oxychlordane, PCB-153, and PCB-180. The comparison of {delta}{sup 15}N with OC concentrations indicated that relative trophic position might not accurately predict OC bioaccumulation in Arctic fox. The bioaccumulation pattern of OCs in the Arctic fox is similar to the polar bear. While {sigma}PCB concentrations were highly variable, concentrations in the Arctic fox were generally below those associated with the toxicological endpoints for adverse effects on mammalian reproduction. Further research is required to properly elucidate the potential health impacts to this species from exposure to OCs.

Organochlorine contaminant and stable isotope profiles in Arctic fox (Alopex lagopus) from the Alaskan and Canadian Arctic

International Nuclear Information System (INIS)

Hoekstra, P.F.; Braune, B.M.; O'Hara, T.M.; Elkin, B.; Solomon, K.R.; Muir, D.C.G.

2003-01-01

PCBs in Arctic fox are lower than reported in other Arctic populations and unlikely to cause significant impairment of reproductive success. - Arctic fox (Alopex lagopus) is a circumpolar species distributed across northern Canada and Alaska. Arctic fox muscle and liver were collected at Barrow, AK, USA (n=18), Holman, NT, Canada (n=20), and Arviat, NU, Canada (n=20) to elucidate the feeding ecology of this species and relate these findings to body residue patterns of organochlorine contaminants (OCs). Stable carbon (δ 13 C) and nitrogen (δ 15 N) isotope analyses of Arctic fox muscle indicated that trophic position (estimated by δ 15 N) is positively correlated with increasing δ 13 C values, suggesting that Arctic fox with a predominately marine-based foraging strategy occupy a higher trophic level than individuals mostly feeding from a terrestrial-based carbon source. At all sites, the rank order for OC groups in muscle was polychlorinated biphenyls (ΣPCB) > chlordane-related compounds (ΣCHLOR) > hexachlorocyclohexane (ΣHCH) > total toxaphene (TOX) ≥chlorobenzenes (ΣClBz) > DDT-related isomers (ΣDDT). In liver, ΣCHLOR was the most abundant OC group, followed by ΣPCB > TOX > ΣHCH > ΣClBz > ΣDDT. The most abundant OC analytes detected from Arctic fox muscle and liver were oxychlordane, PCB-153, and PCB-180. The comparison of δ 15 N with OC concentrations indicated that relative trophic position might not accurately predict OC bioaccumulation in Arctic fox. The bioaccumulation pattern of OCs in the Arctic fox is similar to the polar bear. While ΣPCB concentrations were highly variable, concentrations in the Arctic fox were generally below those associated with the toxicological endpoints for adverse effects on mammalian reproduction. Further research is required to properly elucidate the potential health impacts to this species from exposure to OCs

Into the 21st Century with the Istituto Geografico Polare "Silvio Zavatti" and its journal "Il Polo"

Science.gov (United States)

Casarini, M.

2013-12-01

By Maria Pia Casarini We are now nearing the 70th anniversary of the foundation of this unique institution, established in the city of Fermo in the Marche region of Italy by the late Prof. Silvio Zavatti (d. 1985), a true polar enthusiast working before the time when Italy had any official interest in the polar regions. The Institute has the largest and most comprehensive polar library in Italy; a polar museum with Inuit artifacts and relics of expeditions by the Duke of Abruzzi and Umberto Nobile; and it has published a quarterly journal, "Il Polo", since 1945. Given the increasing official role of Italy in both Arctic and Antarctic research, and the increasing interest of Italian institutions and individuals in the rapidly developing problems of Arctic development, governance and environmental protection, the Institute aims to play an increased role in assisting Italian polar efforts through its resources and scholarship. For instance, the Institute is a member of the Arctic Table at the Italian Foreign Ministry by which Italy's role as an observer in the Arctic Council is mapped. The journal "Il Polo" has become bilingual and is becoming a global polar journal with survey papers by distinguished polar leaders. We are linked with PEI (Polar Educators International), which spreads knowledge of the polar regions in schools.

Changes in Ocean Circulation with an Ice-Free Arctic: Reconstructing Early Holocene Arctic Ocean Circulation Using Geochemical Signals from Individual Neogloboquadrina pachyderma (sinistral) Shells

Science.gov (United States)

Livsey, C.; Spero, H. J.; Kozdon, R.

2016-12-01

The impacts of sea ice decrease and consequent hydrologic changes in the Arctic Ocean will be experienced globally as ocean and atmospheric temperatures continue to rise, though it is not evident to what extent. Understanding the structure of the Arctic water column during the early/mid Holocene sea ice minimum ( 6-10 kya), a post-glacial analogue of a seasonally ice-free Arctic, will help us to predict what the changes we can expect as the Earth warms over the next century. Neogloboquadrina pachyderma (sinistral; Nps) is a species of planktonic foraminifera that dominates assemblages in the polar oceans. This species grows its chambers (ontogenetic calcite) in the surface waters and subsequently descends through the water column to below the mixed layer where it quickly adds a thick crust of calcite (Kohfeld et al., 1996). Therefore, geochemical signals from both the surface waters and sub-mixed layer depths are captured within single Nps shells. We were able to target ion mass spectrometry (SIMS), therefore capturing signals from both the ontogenetic and crust calcite in single Nps shells. This data was combined with laser ablation- inductively coupled mass spectrometry (LA-ICPMS) Mg/Ca profiles of trace metals through the two layers of calcite of the same shells, to determine the thermal structure of the water column. Combining δ18O, temperature, and salinity gradients from locations across the Arctic basin allow us to reconstruct the hydrography of the early Holocene Arctic sea ice minimum. These results will be compared with modern Arctic water column characteristics in order to develop a conceptual model of Arctic Ocean oceanographic change due to global warming. Kohfeld, K.E., Fairbanks, R.G., Smith, S.L., Walsh, I.D., 1996. Neogloboquadrina pachyderma(sinistral coiling) as paleoceanographic tracers in polar oceans: Evidence from northeast water polynya plankton tows, sediment traps, and surface sediments. Paleoceanography 11, 679-699.

Subtropical Arctic Ocean temperatures during the Palaeocene/Eocene thermal maximum

Science.gov (United States)

Sluijs, A.; Schouten, S.; Pagani, M.; Woltering, M.; Brinkhuis, H.; Damste, J.S.S.; Dickens, G.R.; Huber, M.; Reichart, G.-J.; Stein, R.; Matthiessen, J.; Lourens, L.J.; Pedentchouk, N.; Backman, J.; Moran, K.; Clemens, S.; Cronin, T.; Eynaud, F.; Gattacceca, J.; Jakobsson, M.; Jordan, R.; Kaminski, M.; King, J.; Koc, N.; Martinez, N.C.; McInroy, D.; Moore, T.C.; O'Regan, M.; Onodera, J.; Palike, H.; Rea, B.; Rio, D.; Sakamoto, T.; Smith, D.C.; St John, K.E.K.; Suto, I.; Suzuki, N.; Takahashi, K.; Watanabe, M. E.; Yamamoto, M.

2006-01-01

The Palaeocene/Eocene thermal maximum, ???55 million years ago, was a brief period of widespread, extreme climatic warming, that was associated with massive atmospheric greenhouse gas input. Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition. We show that sea surface temperatures near the North Pole increased from ???18??C to over 23??C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. At the same time, sea level rose while anoxic and euxinic conditions developed in the ocean's bottom waters and photic zone, respectively. Increasing temperature and sea level match expectations based on palaeoclimate model simulations, but the absolute polar temperatures that we derive before, during and after the event are more than 10??C warmer than those model-predicted. This suggests that higher-than-modern greenhouse gas concentrations must have operated in conjunction with other feedback mechanisms-perhaps polar stratospheric clouds or hurricane-induced ocean mixing-to amplify early Palaeogene polar temperatures. ?? 2006 Nature Publishing Group.

Optimizing Communications Between Arctic Residents and IPY Scientific Researchers

Science.gov (United States)

Stapleton, M.; Carpenter, L.

2007-12-01

BACKGROUND International Polar Year, which was launched in March 2007, is an international program of coordinated, interdisciplinary scientific research on Earth's polar regions. The northern regions of the eight Arctic States (Canada, Alaska (USA), Russia, Sweden, Norway, Finland. Iceland and Greenland (Denmark) have significant indigenous populations. The circumpolar Arctic is one of the least technologically connected regions in the world, although Canada and others have been pioneers in developing and suing Information and Communication Technology (ICT) in remote areas. The people living in this vast geographic area have been moving toward taking their rightful place in the global information society, but are dependent on the outreach and cooperation of larger mainstream societies. The dominant medium of communication is radio, which is flexible in accommodating multiple cultures, languages, and factors of time and distance. The addition of newer technologies such as streaming on the Internet can increase access and content for all communities of interest, north and south. The Arctic Circle of Indigenous Communicators (ACIC) is an independent association of professional Northern indigenous media workers in the print, radio, television, film and Internet industries. ACIC advocates the development of all forms of communication in circumpolar North areas. It is international in scope. Members are literate in English, French, Russian and many indigenous languages. ACIC has proposed the establishment of a headquarters for monitoring IPY projects are in each area, and the use of community radio broadcasters to collect and disseminate information about IPY. The cooperation of Team IPY at the University of Colorado, Arctic Net at Laval University, and others, is being developed. ACIC is committed to making scientific knowledge gained in IPY accessible to those most affected - residents of the Arctic. ABSTRACT The meeting of the American Geophysical Union will be held

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.

Assessing performance of gravity models in the Arctic and the implications for polar oceanography

Science.gov (United States)

Thomas, S. F.; McAdoo, D. C.; Farrell, S. L.; Brozena, J. M.; Childers, V. A.; Ziebart, M. K.; Shepherd, A.

2014-12-01

The circulation of the Arctic Ocean is of great interest to both the oceanographic and cryospheric communities. Understanding both the steady state and variations of this circulation is essential to building our knowledge of Arctic climate. With the advent of high inclination altimeter missions such as CryoSat and ICESat, it is now feasible to produce Mean Dynamic Topography (MDT) products for the region, which allow a comprehensive investigation of geostrophic currents. However, the accuracy of these products is largely limited by our knowledge of the marine geoid in the Arctic. There are a number of publicly available gravity models commonly used to derive the geoid. These use different combinations of available data (satellite gravimetry, altimetry, laser ranging, and in-situ) and are calculated using different mathematical techniques. However, the effect of these differences on the real world performance of these models when used for oceanographic studies in the Arctic is not well known. Given the unique problems for gravimetry in the region (especially data gaps) and their potential impact on MDT products, it is especially important that the relative performance of these models be assessed We consider the needs of the "end user" satellite oceanographer in the Arctic with respect to gravimetry, and the relationship between the precision of gravity data and the accuracy of a final MDT/current velocity product. Using high-precision aerogravity data collected over 3 years of campaigns by NASA's Operation IceBridge we inter-compare 10 of the leading gravity models and assess their performance in the Arctic. We also use historical data from campaigns flown by the US Naval Research Laboratory (NRL) to demonstrate the impact of gravity errors on MDT products. We describe how gravity models for the region might be improved in the future, in an effort to maximize the level at which Arctic currents may be resolved.

Collaborative Proposal: Improving Decadal Prediction of Arctic Climate Variability and Change Using a Regional Arctic System Model (RASM)

Energy Technology Data Exchange (ETDEWEB)

Maslowski, Wieslaw [Naval Postgraduate School, Monterey, CA (United States)

2016-10-17

This project aims to develop, apply and evaluate a regional Arctic System model (RASM) for enhanced decadal predictions. Its overarching goal is to advance understanding of the past and present states of arctic climate and to facilitate improvements in seasonal to decadal predictions. In particular, it will focus on variability and long-term change of energy and freshwater flows through the arctic climate system. The project will also address modes of natural climate variability as well as extreme and rapid climate change in a region of the Earth that is: (i) a key indicator of the state of global climate through polar amplification and (ii) which is undergoing environmental transitions not seen in instrumental records. RASM will readily allow the addition of other earth system components, such as ecosystem or biochemistry models, thus allowing it to facilitate studies of climate impacts (e.g., droughts and fires) and of ecosystem adaptations to these impacts. As such, RASM is expected to become a foundation for more complete Arctic System models and part of a model hierarchy important for improving climate modeling and predictions.

A History of Coastal Research in the Arctic (Invited)

Science.gov (United States)

Walker, H. J.; McGraw, M.

2009-12-01

The arctic shoreline is, according to the CIA World Factbook, 45,389 km long. However, a more realistic length from the standpoint of detailed research is the 200,000 km proposed at the 1999 Arctic Coastal Dynamics Workshop. Highly varied in form and material it is dominated by a variety of processes, is relatively remote, is ice-bound much of the year, and has generally been neglected by the scientific community. Before the 20th century, most of the information about its geology, hydrology, geomorphology, and biology was recorded in ship's logs or in explorer's books and was for the most part incidental to the narrative being related. The paucity of specific research is indicated by the relatively few relevant papers included in the more than 100,000 annotated entries published in the 15 volumes of the Arctic Bibliography (1953-1971) and in the nearly as extensive 27 volume bibliography prepared by the Cold Regions Research and Engineering Laboratory (CRREL) between 1952 and 1973. Nonetheless, there were some distinctive research endeavors during the early part of the 20th century; e.g., Leffingwell's 1919 Alaskan Arctic Coast observations, Nansen's 1921 strandflat studies, and Zenkovich's 1937 Murmansk research. During that period some organizations devoted to polar research, especially the USSR's Arctic and Antarctic Research Institute and the Scott Polar Research Institute (both in 1920) were established, although the amount of their research that could be considered coastal and arctic was limited. Specific research of the arctic's shoreline was mainly academic until after World War II when military, economic, industrial, and archaeological interests began demanding reliable, contemporary data. At the time numerous organizations with a primary focus on the Arctic were formed. Included are the Arctic Institute of North America (1945), the Snow, Ice, and Permafrost Research Establishment (latter to become CRREL) and the Office of Naval Research's Arctic Research

Anthropogenic Radionuglides in Marine Polar Regions

Science.gov (United States)

Holm, Elis

The polar regions are important for the understanding of long range water and atmospheric transport of anthropogenic substances. Investigations show that atmospheric transport of anthropogenic radionuclides is the most important route of transport to the Antarctic while water transport plays a greater role for the Arctic. Fallout from nuclear detonation tests is the major source in the Antarctic while in the Arctic other sources, especially European reprocessing facilities, dominate for conservatively behaving rdionuclides such as 137Cs . The flux of 137Cs and 239+240Pu in the Antarctic is about 1/10 of that for the Arctic and the resulting concentrations in surface sea-water show the same ratio for the two areas. In the Antarctic concentration factors for 137Cs are higher than in the Arctic for similar species

The Arctic Coastal Erosion Problem

Energy Technology Data Exchange (ETDEWEB)

Frederick, Jennifer M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Thomas, Matthew Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Craig A. [Integral Consulting Inc., San Francisco, CA (United States); Roberts, Jesse D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-09-01

Permafrost-dominated coastlines in the Arctic are rapidly disappearing. Arctic coastal erosion rates in the United States have doubled since the middle of the twentieth century and appear to be accelerating. Positive erosion trends have been observed for highly-variable geomorphic conditions across the entire Arctic, suggesting a major (human-timescale) shift in coastal landscape evolution. Unfortunately, irreversible coastal land loss in this region poses a threat to native, industrial, scientific, and military communities. The Arctic coastline is vast, spanning more than 100,000 km across eight nations, ten percent of which is overseen by the United States. Much of area is inaccessible by all-season roads. People and infrastructure, therefore, are commonly located near the coast. The impact of the Arctic coastal erosion problem is widespread. Homes are being lost. Residents are being dispersed and their villages relocated. Shoreline fuel storage and delivery systems are at greater risk. The U.S. Department of Energy (DOE) and Sandia National Laboratories (SNL) operate research facilities along some of the most rapidly eroding sections of coast in the world. The U.S. Department of Defense (DOD) is struggling to fortify coastal radar sites, operated to ensure national sovereignty in the air, against the erosion problem. Rapid alterations to the Arctic coastline are facilitated by oceanographic and geomorphic perturbations associated with climate change. Sea ice extent is declining, sea level is rising, sea water temperature is increasing, and permafrost state is changing. The polar orientation of the Arctic exacerbates the magnitude and rate of the environmental forcings that facilitate coastal land area loss. The fundamental mechanics of these processes are understood; their non-linear combination poses an extreme hazard. Tools to accurately predict Arctic coastal erosion do not exist. To obtain an accurate predictive model, a coupling of the influences of

Circumpolar Genetic Structure and Recent Gene Flow of Polar Bears: A Reanalysis.

Science.gov (United States)

Malenfant, René M; Davis, Corey S; Cullingham, Catherine I; Coltman, David W

2016-01-01

Recently, an extensive study of 2,748 polar bears (Ursus maritimus) from across their circumpolar range was published in PLOS ONE, which used microsatellites and mitochondrial haplotypes to apparently show altered population structure and a dramatic change in directional gene flow towards the Canadian Archipelago-an area believed to be a future refugium for polar bears as their southernmost habitats decline under climate change. Although this study represents a major international collaborative effort and promised to be a baseline for future genetics work, methodological shortcomings and errors of interpretation undermine some of the study's main conclusions. Here, we present a reanalysis of this data in which we address some of these issues, including: (1) highly unbalanced sample sizes and large amounts of systematically missing data; (2) incorrect calculation of FST and of significance levels; (3) misleading estimates of recent gene flow resulting from non-convergence of the program BayesAss. In contrast to the original findings, in our reanalysis we find six genetic clusters of polar bears worldwide: the Hudson Bay Complex, the Western and Eastern Canadian Arctic Archipelago, the Western and Eastern Polar Basin, and-importantly-we reconfirm the presence of a unique and possibly endangered cluster of bears in Norwegian Bay near Canada's expected last sea-ice refugium. Although polar bears' abundance, distribution, and population structure will certainly be negatively affected by ongoing-and increasingly rapid-loss of Arctic sea ice, these genetic data provide no evidence of strong directional gene flow in response to recent climate change.

Circumpolar Genetic Structure and Recent Gene Flow of Polar Bears: A Reanalysis.

Directory of Open Access Journals (Sweden)

René M Malenfant

Full Text Available Recently, an extensive study of 2,748 polar bears (Ursus maritimus from across their circumpolar range was published in PLOS ONE, which used microsatellites and mitochondrial haplotypes to apparently show altered population structure and a dramatic change in directional gene flow towards the Canadian Archipelago-an area believed to be a future refugium for polar bears as their southernmost habitats decline under climate change. Although this study represents a major international collaborative effort and promised to be a baseline for future genetics work, methodological shortcomings and errors of interpretation undermine some of the study's main conclusions. Here, we present a reanalysis of this data in which we address some of these issues, including: (1 highly unbalanced sample sizes and large amounts of systematically missing data; (2 incorrect calculation of FST and of significance levels; (3 misleading estimates of recent gene flow resulting from non-convergence of the program BayesAss. In contrast to the original findings, in our reanalysis we find six genetic clusters of polar bears worldwide: the Hudson Bay Complex, the Western and Eastern Canadian Arctic Archipelago, the Western and Eastern Polar Basin, and-importantly-we reconfirm the presence of a unique and possibly endangered cluster of bears in Norwegian Bay near Canada's expected last sea-ice refugium. Although polar bears' abundance, distribution, and population structure will certainly be negatively affected by ongoing-and increasingly rapid-loss of Arctic sea ice, these genetic data provide no evidence of strong directional gene flow in response to recent climate change.

Pan-Arctic TV Series on Inuit wellness: a northern model of communication for social change?

Science.gov (United States)

Johnson, Rhonda; Morales, Robin; Leavitt, Doreen; Carry, Catherine; Kinnon, Dianne; Rideout, Denise; Clarida, Kath

2011-06-01

This paper provides highlights of a utilization-focused evaluation of a collaborative Pan-Arctic Inuit Wellness TV Series that was broadcast live in Alaska and Canada in May 2009. This International Polar Year (IPY) communication and outreach project intended to (1) share information on International Polar Year research progress, disseminate findings and explore questions with Inuit in Alaska, Canada and Greenland; (2) provide a forum for Inuit in Alaska, Canada and Greenland to showcase innovative health and wellness projects; (3) ensure Inuit youth and adult engagement throughout; and (4) document and reflect on the overall experience for the purposes of developing and "testing" a participatory communication model. Utilization-focused formative evaluation of the project, with a focus on overall objectives, key messages and lessons learned to facilitate program improvement. Participant observation, surveys, key informant interviews, document review and website tracking. Promising community programs related to 3 themes - men's wellness, maternity care and youth resilience - in diverse circumpolar regions were highlighted, as were current and stillevolving findings from ongoing Arctic research. Multiple media methods were used to effectively deliver and receive key messages determined by both community and academic experts. Local capacity and new regional networks were strengthened. Evidence-based resources for health education and community action were archived in digital formats (websites and DVDs), increasing accessibility to otherwise isolated individuals and remote communities. The Pan-Arctic Inuit Wellness TV Series was an innovative, multi-dimensional communication project that raised both interest and awareness about complex health conditions in the North and stimulated community dialogue and potential for increased collaborative action. Consistent with a communication for social change approach, the project created new networks, increased motivation to act

One Model for Scientist Involvement in K-12 Education: Teachers Experiencing Antarctica and the Arctic Program

Science.gov (United States)

Meese, D.; Shipp, S. S.; Porter, M.; Bruccoli, A.

2002-12-01

Scientists involved in the NSF-funded Teachers Experiencing Antarctica and the Arctic (TEA) Program integrate a K-12 science teacher into their polar field project. Objectives of the program include: having the science teacher immersed in the experience of research; 2) through the teacher, leveraging the research experience to better inform teaching practices; and 3) sharing the experience with the broader educational and general community. The scientist - or qualified team member - stays involved with the teacher throughout the program as a mentor. Preparation of the teacher involves a week-long orientation presented by the TEA Program, and a two week pre-expedition visit at the scientist's institution. Orientation acquaints teachers with program expectations, logistical information, and an overview of polar science. While at the scientist's institution, the teacher meets the team, prepares for the field, and strengthens content knowledge. In the field, the teacher is a team member and educational liaison, responding to questions from students and colleagues by e-mail, and posting electronic journals describing the research experience. Upon return, the teachers work closely with colleagues to bring the experience of research into classrooms through creation of activities, design of longer-term student investigations, and presentations at scientific, educational, and community meetings. Interaction with the scientific team continues with a visit by the scientist to the teacher's classrooms, collaboration on presentations at scientific meetings, and consultation on classroom activities. In some cases, the teacher may participate in future expeditions. The involvement by scientists in mentor relationships, such as those of the TEA Program, is critical to improving science education. Many teachers of science have not had the opportunity to participate in field research, which offers valuable first-hand experience about the nature of science, as well as about specific

Settlements in an Arctic Resource Frontier Region

NARCIS (Netherlands)

Hacquebord, L.; Avango, D.

2009-01-01

In this article we use a core-periphery model in order to understand the general trends in the history of natural resource exploitation in the polar regions. The study focuses on whaling, hunting, and coal mining activities on the European High Arctic archipelago of Spitsbergen, from the seventeenth

Simulation of Extreme Arctic Cyclones in IPCC AR5 Experiments

Science.gov (United States)

Vavrus, S. J.

2012-12-01

Although impending Arctic climate change is widely recognized, a wild card in its expression is how extreme weather events in this region will respond to greenhouse warming. Intense polar cyclones represent one type of high-latitude phenomena falling into this category, including very deep synoptic-scale cyclones and mesoscale polar lows. These systems inflict damage through high winds, heavy precipitation, and wave action along coastlines, and their impact is expected to expand in the future, when reduced sea ice cover allows enhanced wave energy. The loss of a buffering ice pack could greatly increase the rate of coastal erosion, which has already been increasing in the Arctic. These and related threats may amplify if extreme Arctic cyclones become more frequent and/or intense in a warming climate with much more open water to fuel them. This possibility has merit on the basis of GCM experiments, which project that greenhouse forcing causes lower mean sea level pressure (SLP) in the Arctic and a strengthening of the deepest storms over boreal high latitudes. In this study, the latest Coupled Model Intercomparison Project (CMIP5) climate model output is used to investigate the following questions: (1) What are the spatial and seasonal characteristics of extreme Arctic cyclones? (2) How well do GCMs simulate these phenomena? (3) Are Arctic cyclones already showing the expected response to greenhouse warming in climate models? To address these questions, a retrospective analysis is conducted of the transient 20th century simulations among the CMIP5 GCMs (spanning years 1850-2005). The results demonstrate that GCMs are able to reasonably represent extreme Arctic cyclones and that the simulated characteristics do not depend significantly on model resolution. Consistent with observational evidence, climate models generate these storms primarily during winter and within the climatological Aleutian and Icelandic Low regions. Occasionally the cyclones remain very intense

Nostalgisk erindring og polar karrierehistorie. Fridtjof Nansen: Blant sel og bjørn: min første ishavs-ferd (1924

Directory of Open Access Journals (Sweden)

Silje Solheim Karlsen

2012-05-01

Full Text Available In Fridtjof Nansens Hunting & adventure in the Arctic (1924, the last polar travel account Nansen wrote, he writes about his first experience with the Arctic; when he as a young student in 1882 joined the sealboat Viking to the sealing grounds outsideGreenland. The account is a polyphonic book where both the young student and the 63 year old scientist and polar hero alternately speaks. The young Nansen seems overwhelmed by the Arctic surroundings, he tells enthusiastically of ice, polar bears, hunting and the sealing. The old scientist explains the nature and whole fauna in the Arctic, supported by his own experiences and all research available. The result is, on the one hand, a nostalgic travelbook which also functions as a memoir over the totalof Nansen´s Arctic travels and expeditions. On the other hand, the convincing andthorough scientific material in the book positions Nansen as an authority both what regards science, but perhaps just as important: as a successful polar explorer and hero.

Variability of the Arctic Basin Oceanographic Fields

National Research Council Canada - National Science Library

Sabinin, K

1996-01-01

...." Special attention was paid to Atlantic Water in the Arctic Ocean which seems to be the main source of information in acoustic monitoring of the ocean, in the framework of the Arctic-ATOC program...

Trophic relationships in an Arctic food web and implications for trace metal transfer

Energy Technology Data Exchange (ETDEWEB)

Dehn, Larissa-A. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, 99775-7000 (United States)]. E-mail: ftld@uaf.edu; Follmann, Erich H. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, 99775-7000 (United States); Thomas, Dana L. [Department of Mathematical Sciences, University of Alaska Fairbanks, Fairbanks, Alaska, 99775-6660 (United States); Sheffield, Gay G. [Alaska Department of Fish and Game, Fairbanks, Division of Wildlife Conservation, Fairbanks, Alaska, 99701-1599 (United States); Rosa, Cheryl [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, 99775-7000 (United States); Duffy, Lawrence K. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, 99775-7000 (United States); O' Hara, Todd M. [Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, 99775-7000 (United States)

2006-06-01

Tissues of subsistence-harvested Arctic mammals were analyzed for silver (Ag), cadmium (Cd), and total mercury (THg). Muscle (or total body homogenates of potential fish and invertebrate prey) was analyzed for stable carbon ({delta} {sup 13}C) and nitrogen ({delta} {sup 15}N) isotopes to establish trophic interactions within the Arctic food chain. Food web magnification factors (FWMFs) and biomagnification factors for selected predator-prey scenarios (BMFs) were calculated to describe pathways of heavy metals in the Alaskan Arctic. FWMFs in this study indicate that magnification of selected heavy metals in the Arctic food web is not significant. Biomagnification of Cd occurs mainly in kidneys; calculated BMFs are higher for hepatic THg than renal THg for all predator-prey scenarios with the exception of polar bears (Ursus maritimus). In bears, the accumulation of renal THg is approximately 6 times higher than in liver. Magnification of hepatic Ag is minimal for all selected predator-prey scenarios. Though polar bears occupy a higher trophic level than belugas (Delphinapterus leucas), based on {delta} {sup 15}N, the metal concentrations are either not statistically different between the two species or lower for bears. Similarly, concentrations of renal and hepatic Cd are significantly lower or not statistically different in polar bears compared to ringed (Phoca hispida) and bearded seals (Erignathus barbatus), their primary prey. THg, on the other hand, increased significantly from seal to polar bear tissues. Mean {delta} {sup 15}N was lowest in muscle of Arctic fox (Alopex lagopus) and foxes also show the lowest levels of Hg, Cd and Ag in liver and kidney compared to the other species analyzed. These values are in good agreement with a diet dominated by terrestrial prey. Metal deposition in animal tissues is strongly dependent on biological factors such as diet, age, sex, body condition and health, and caution should be taken when interpreting magnification of

Trophic relationships in an Arctic food web and implications for trace metal transfer

International Nuclear Information System (INIS)

Dehn, Larissa-A.; Follmann, Erich H.; Thomas, Dana L.; Sheffield, Gay G.; Rosa, Cheryl; Duffy, Lawrence K.; O'Hara, Todd M.

2006-01-01

Tissues of subsistence-harvested Arctic mammals were analyzed for silver (Ag), cadmium (Cd), and total mercury (THg). Muscle (or total body homogenates of potential fish and invertebrate prey) was analyzed for stable carbon (δ 13 C) and nitrogen (δ 15 N) isotopes to establish trophic interactions within the Arctic food chain. Food web magnification factors (FWMFs) and biomagnification factors for selected predator-prey scenarios (BMFs) were calculated to describe pathways of heavy metals in the Alaskan Arctic. FWMFs in this study indicate that magnification of selected heavy metals in the Arctic food web is not significant. Biomagnification of Cd occurs mainly in kidneys; calculated BMFs are higher for hepatic THg than renal THg for all predator-prey scenarios with the exception of polar bears (Ursus maritimus). In bears, the accumulation of renal THg is approximately 6 times higher than in liver. Magnification of hepatic Ag is minimal for all selected predator-prey scenarios. Though polar bears occupy a higher trophic level than belugas (Delphinapterus leucas), based on δ 15 N, the metal concentrations are either not statistically different between the two species or lower for bears. Similarly, concentrations of renal and hepatic Cd are significantly lower or not statistically different in polar bears compared to ringed (Phoca hispida) and bearded seals (Erignathus barbatus), their primary prey. THg, on the other hand, increased significantly from seal to polar bear tissues. Mean δ 15 N was lowest in muscle of Arctic fox (Alopex lagopus) and foxes also show the lowest levels of Hg, Cd and Ag in liver and kidney compared to the other species analyzed. These values are in good agreement with a diet dominated by terrestrial prey. Metal deposition in animal tissues is strongly dependent on biological factors such as diet, age, sex, body condition and health, and caution should be taken when interpreting magnification of dynamic and actively regulated trace metals

The "Physical feedbacks of Arctic PBL, Sea ice, Cloud and AerosoL (PASCAL)" campaign during the Arctic POLARSTERN expedition PS106 in spring 2017.

Science.gov (United States)

Macke, A.

2017-12-01

The Polar regions are important components in the global climate system. The widespread surface snow and ice cover strongly impacts the surface energy budget, which is tightly coupled to global atmospheric and oceanic circulations. The coupling of sea ice, clouds and aerosol in the transition zone between Open Ocean and sea ice is the focus of the PASCAL investigations to improve our understanding of the recent dramatic reduction in Arctic sea-ice. A large variety of active/passive remote sensing, in-situ-aerosol observation, and spectral irradiance measurements have been obtained during the German research icebreaker POLARSTERN expedition PS106, and provided detailed information on the atmospheric spatiotemporal structure, aerosol and cloud chemical and microphysical properties as well as the resulting surface radiation budget. Nearly identical measurements at the AWIPEV Base (German - French Research Base) in Ny-Ålesund close to the Open Ocean and collocated airborne activities of the POLAR 5 and POLAR 6 AWI aircraft in the framework of the ACLOUD project have been carried out in parallel. The airborne observations have been supplemented by observations of the boundary layer structure (mean and turbulent quantities) from a tethered balloon reaching up to 1500 m, which was operated at an ice floe station nearby POLARSTERN for two weeks. All observational activities together with intense modelling at various scales are part of the German Collaborative Research Cluster TR 172 "Arctic Amplification" that aims to provide an unprecedented picture of the complex Arctic weather and climate system. The presentation provides an overview of the measurements on-board POLARSTERN and on the ice floe station during PASCAL from May 24 to July 21 2017. We conclude how these and future similar measurements during the one-year ice drift of POLARSTERN in the framework of MOSAiC help to reduce uncertainties in Arctic aerosol-cloud interaction, cloud radiative forcing, and surface

Advancing Environmental Prediction Capabilities for the Polar Regions and Beyond during The Year of Polar Prediction

Science.gov (United States)

Werner, Kirstin; Goessling, Helge; Hoke, Winfried; Kirchhoff, Katharina; Jung, Thomas

2017-04-01

Environmental changes in polar regions open up new opportunities for economic and societal operations such as vessel traffic related to scientific, fishery and tourism activities, and in the case of the Arctic also enhanced resource development. The availability of current and accurate weather and environmental information and forecasts will therefore play an increasingly important role in aiding risk reduction and safety management around the poles. The Year of Polar Prediction (YOPP) has been established by the World Meteorological Organization's World Weather Research Programme as the key activity of the ten-year Polar Prediction Project (PPP; see more on www.polarprediction.net). YOPP is an internationally coordinated initiative to significantly advance our environmental prediction capabilities for the polar regions and beyond, supporting improved weather and climate services. Scheduled to take place from mid-2017 to mid-2019, the YOPP core phase covers an extended period of intensive observing, modelling, prediction, verification, user-engagement and education activities in the Arctic and Antarctic, on a wide range of time scales from hours to seasons. The Year of Polar Prediction will entail periods of enhanced observational and modelling campaigns in both polar regions. With the purpose to close the gaps in the conventional polar observing systems in regions where the observation network is sparse, routine observations will be enhanced during Special Observing Periods for an extended period of time (several weeks) during YOPP. This will allow carrying out subsequent forecasting system experiments aimed at optimizing observing systems in the polar regions and providing insight into the impact of better polar observations on forecast skills in lower latitudes. With various activities and the involvement of a wide range of stakeholders, YOPP will contribute to the knowledge base needed to managing the opportunities and risks that come with polar climate change.

SYMPOSIUM ON REMOTE SENSING IN THE POLAR REGIONS

Science.gov (United States)

The Arctic Institute of North America long has been interested in encouraging full and specific attention to applications of remote sensing to polar...research problems. The major purpose of the symposium was to acquaint scientists and technicians concerned with remote sensing with some of the...special problems of the polar areas and, in turn, to acquaint polar scientists with the potential of the use of remote sensing . The Symposium therefore was

Radio-positioning for arctic seismic refraction surveys

Energy Technology Data Exchange (ETDEWEB)

Dearnley-Davison, J. (Dept. of Fisheries and Oceans, Dartmouth, NS (Canada)); Forsyth, D.A. (Continental Geoscience Div., Geological Survey of Canada, Ottawa, ON (Canada))

1989-12-01

The full extent of hydrocarbon reserves within Canada's Arctic margin is not appreciated at present. With the exception of the southern Beaufort Sea, the crustal structure of most of Canada's offshore polar margin remains a mystery, even at reconnaissance level. Navigation to support offshore Arctic surveys have required a special application and adaptation of the conventional SYLEDIS (SYsteme LEgere de DIStance) range-range navigational system to perform under the northeast Actic margin's environment. Once adapted, the system has proven very effective with a few Arctic environment servicing problems. The total number of locations involved in the earlier surveys ranged from 20 to aproximately 50 per project in a season. The SYLEDIS operation has enabled real-time positioning with a precision of better than 10 metres for approximately 350 separate sites in the 1985 and 1986 surveys inclusive. 2 refs., 3 figs.

Arctic Collaboration: Developing a Successful Researcher/Teacher Expedition

Science.gov (United States)

Skotnicki, S.; Loranty, M. M.

2016-12-01

Are you a researcher working in the polar regions of the world or a K-12 science teacher who would like to be part of a field research expedition in the polar regions? Researchers and K-12 science teachers can apply for funding from PolarTREC, a program that pairs researchers and teachers to conduct field science in Antarctica and the Arctic. Our poster presentation will offer details of one such successful researcher/teacher partnership. During the summer of 2016, Science Teacher Stan Skotnicki (Cheektowaga Central Middle School in Buffalo, NY) was teamed up with Assistant Professor Mike Loranty (Colgate University) to study vegetation and ecosystem impacts on permafrost vulnerability. Stan joined Mike and his research team in Northeastern Siberia preparing field sites, collecting data, processing samples, discussing methods, and planning daily activities. In order to raise awareness and broaden the impact of the research being conducted, Stan communicated the science through a series of journals on the PolarTREC website with his students, staff, and members of the community. Additionally, Mike and Stan held a live webinar from Siberia discussing the content of the research, the nature of the fieldwork, and why it was important to travel so far for this information. This expedition allowed Stan to experience working with a field research team for an extended period of time. Mike benefited from having a team member dedicated to learning about and communicating project details that also provided valuable field assistance. Stan gets to bring his hands-on experience back to his classroom in Buffalo and Mike has the opportunity to share his research with a new and different audience, including presenting to students at Cheektowaga Central with the help of his undergraduate students. This model of collaboration provides a number of valuable benefits for both teachers and researchers. While the PolarTREC program provides necessary logistics and funding to conduct these

The Arctic Cooperative Data and Information System: Data Management Support for the NSF Arctic Research Program (Invited)

Science.gov (United States)

Moore, J.; Serreze, M. C.; Middleton, D.; Ramamurthy, M. K.; Yarmey, L.

2013-12-01

The NSF funds the Advanced Cooperative Arctic Data and Information System (ACADIS), url: (http://www.aoncadis.org/). It serves the growing and increasingly diverse data management needs of NSF's arctic research community. The ACADIS investigator team combines experienced data managers, curators and software engineers from the NSIDC, UCAR and NCAR. ACADIS fosters scientific synthesis and discovery by providing a secure long-term data archive to NSF investigators. The system provides discovery and access to arctic related data from this and other archives. This paper updates the technical components of ACADIS, the implementation of best practices, the value of ACADIS to the community and the major challenges facing this archive for the future in handling the diverse data coming from NSF Arctic investigators. ACADIS provides sustainable data management, data stewardship services and leadership for the NSF Arctic research community through open data sharing, adherence to best practices and standards, capitalizing on appropriate evolving technologies, community support and engagement. ACADIS leverages other pertinent projects, capitalizing on appropriate emerging technologies and participating in emerging cyberinfrastructure initiatives. The key elements of ACADIS user services to the NSF Arctic community include: data and metadata upload; support for datasets with special requirements; metadata and documentation generation; interoperability and initiatives with other archives; and science support to investigators and the community. Providing a self-service data publishing platform requiring minimal curation oversight while maintaining rich metadata for discovery, access and preservation is challenging. Implementing metadata standards are a first step towards consistent content. The ACADIS Gateway and ADE offer users choices for data discovery and access with the clear objective of increasing discovery and use of all Arctic data especially for analysis activities

Genetic signatures of adaptation revealed from transcriptome sequencing of Arctic and red foxes.

Science.gov (United States)

Kumar, Vikas; Kutschera, Verena E; Nilsson, Maria A; Janke, Axel

2015-08-07

adaptation in foxes. Similar to polar bears, fat metabolism seems to play a central role in adaptation of Arctic foxes to the cold climate, as has been identified in the polar bear, another arctic specialist.

Global Hawk dropsonde observations of the Arctic atmosphere obtained during the Winter Storms and Pacific Atmospheric Rivers (WISPAR field campaign

Directory of Open Access Journals (Sweden)

J. M. Intrieri

2014-11-01

Full Text Available In February and March of 2011, the Global Hawk unmanned aircraft system (UAS was deployed over the Pacific Ocean and the Arctic during the Winter Storms and Pacific Atmospheric Rivers (WISPAR field campaign. The WISPAR science missions were designed to (1 mprove our understanding of Pacific weather systems and the polar atmosphere; (2 evaluate operational use of unmanned aircraft for investigating these atmospheric events; and (3 demonstrate operational and research applications of a UAS dropsonde system at high latitudes. Dropsondes deployed from the Global Hawk successfully obtained high-resolution profiles of temperature, pressure, humidity, and wind information between the stratosphere and surface. The 35 m wingspan Global Hawk, which can soar for ~ 31 h at altitudes up to ~ 20 km, was remotely operated from NASA's Dryden Flight Research Center at Edwards Air Force Base (AFB in California. During the 25 h polar flight on 9–10 March 2011, the Global Hawk released 35 sondes between the North Slope of Alaska and 85° N latitude, marking the first UAS Arctic dropsonde mission of its kind. The polar flight transected an unusually cold polar vortex, notable for an associated record-level Arctic ozone loss, and documented polar boundary layer variations over a sizable ocean–ice lead feature. Comparison of dropsonde observations with atmospheric reanalyses reveal that, for this day, large-scale structures such as the polar vortex and air masses are captured by the reanalyses, while smaller-scale features, including low-level jets and inversion depths, are mischaracterized. The successful Arctic dropsonde deployment demonstrates the capability of the Global Hawk to conduct operations in harsh, remote regions. The limited comparison with other measurements and reanalyses highlights the potential value of Arctic atmospheric dropsonde observations where routine in situ measurements are practically nonexistent.

Assessment of neurotoxic effects of mercury in beluga whales (Delphinapterus leucas), ringed seals (Pusa hispida), and polar bears (Ursus maritimus) from the Canadian Arctic.

Science.gov (United States)

Krey, Anke; Ostertag, Sonja K; Chan, Hing Man

2015-03-15

Marine mammals are indicator species of the Arctic ecosystem and an integral component of the traditional Inuit diet. The potential neurotoxic effects of increased mercury (Hg) in beluga whales (Delphinapterus leucas), ringed seals (Pusa hispida), and polar bears (Ursus maritimus) are not clear. We assessed the risk of Hg-associated neurotoxicity to these species by comparing their brain Hg concentrations with threshold concentrations for toxic endpoints detected in laboratory animals and field observations: clinical symptoms (>6.75 mg/kg wet weight (ww)), neuropathological signs (>4 mg/kg ww), neurochemical changes (>0.4 mg/kg ww), and neurobehavioral changes (>0.1mg/kg ww). The total Hg (THg) concentrations in the cerebellum and frontal lobe of ringed seals and polar bears were 3mg/kg ww. Our results suggest that brain THg levels in polar bears are below levels that induce neurobehavioral effects as reported in the literature, while THg concentrations in ringed seals are within the range that elicit neurobehavioral effects and individual ringed seals exceed the threshold for neurochemical changes. The relatively high THg concentration in beluga whales exceeds all of the neurotoxicity thresholds assessed. High brain selenium (Se):Hg molar ratios were observed in all three species, suggesting that Se could protect the animals from Hg-associated neurotoxicity. This assessment was limited by several factors that influence neurotoxic effects in animals, including: animal species; form of Hg in the brain; and interactions with modifiers of Hg-associated toxicity, such as Se. Comparing brain Hg concentrations in wildlife with concentrations of appropriate laboratory studies can be used as a tool for risk characterization of the neurotoxic effects of Hg in Arctic marine mammals. Copyright © 2014 Elsevier B.V. All rights reserved.

Polar marine ecosystems: major threats and future change

Energy Technology Data Exchange (ETDEWEB)

Clarke, A. [British Antarctic Survey, Cambridge (United Kingdom); Harris, C.M. [Environmental Research and Assessment, Grantchester (United Kingdom)

2003-07-01

This review of polar marine ecosystems covers both the Arctic and Antarctic, identifying the major threats and, where possible, predicting their possible state(s) in 2025. Although the two polar regions are similar in their extreme photoperiod, low temperatures, and in being heavily influenced by snow and ice, in almost all other respects they are very different. The Arctic Ocean is a basin surrounded by continental landmasses close to, and influenced by, large populations and industrial activities. In contrast, the Southern Ocean is contiguous with all the other great oceans and surrounds a single land mass; Antarctica is remote from major centres of population and sources of pollution. Marine environments in both Polar Regions have been highly disturbed by fishing activity, but, in terms of pollution, some areas remain among the most pristine in the world. There are, however, both local and global pressures. Over the 2025 time horizon, the greatest concern for the Arctic is probably the ecological implications of climate change, particularly insofar as sea ice extent and duration are likely to be affected. Such changes are not expected to be as pronounced in the Southern Ocean over this time period, and concerns are related more to direct threats from harvesting of marine living resources, and the ability to manage these fisheries sustainably. In both Polar Regions, the capacity of marine ecosystems to withstand the cumulative impact of a number of pressures, including climate change, pollution and overexploitation, acting synergistically is of greatest concern. (author)

Can polar bear hairs absorb environmental energy?

Directory of Open Access Journals (Sweden)

He Ji-Huan

2011-01-01

Full Text Available A polar bear (Ursus maritimus has superior ability to survive in harsh Arctic regions, why does the animal have such an excellent thermal protection? The present paper finds that the unique labyrinth cavity structure of the polar bear hair plays an important role. The hair can not only prevent body temperature loss but can also absorb energy from the environment.

Polar front associated variation in prokaryotic community structure in Arctic shelf seafloor.

Science.gov (United States)

Nguyen, Tan T; Landfald, Bjarne

2015-01-01

Spatial variations in composition of marine microbial communities and its causes have largely been disclosed in studies comprising rather large environmental and spatial differences. In the present study, we explored if a moderate but temporally permanent climatic division within a contiguous arctic shelf seafloor was traceable in the diversity patterns of its bacterial and archaeal communities. Soft bottom sediment samples were collected at 10 geographical locations, spanning spatial distances of up to 640 km, transecting the oceanic polar front in the Barents Sea. The northern sampling sites were generally colder, less saline, shallower, and showed higher concentrations of freshly sedimented phytopigments compared to the southern study locations. Sampling sites depicted low variation in relative abundances of taxa at class level, with persistent numerical dominance by lineages of Gamma- and Deltaproteobacteria (57-66% of bacterial sequence reads). The Archaea, which constituted 0.7-1.8% of 16S rRNA gene copy numbers in the sediment, were overwhelmingly (85.8%) affiliated with the Thaumarchaeota. Beta-diversity analyses showed the environmental variations throughout the sampling range to have a stronger impact on the structuring of both the bacterial and archaeal communities than spatial effects. While bacterial communities were significantly influenced by the combined effect of several weakly selective environmental differences, including temperature, archaeal communities appeared to be more uniquely structured by the level of freshly sedimented phytopigments.

"Live from IPY"--Connecting Students, Teachers and the Public to Polar Research

Science.gov (United States)

Breen, K.; Warnick, W. K.; Warburton, J.; Fischer, K.; Wiggins, H.

2007-12-01

PolarTREC-Teachers and Researchers Exploring and Collaborating is a three-year (2007-2009) teacher professional development program of the Arctic Research Consortium of the U.S. (ARCUS) that pairs K-12 teachers with researchers to improve science education through authentic polar research experiences. Each year of PolarTREC, approximately 15 teachers spend two to six weeks in the Arctic or Antarctic, working closely with researchers investigating a wide range of topics such as sea-ice dynamics, terrestrial ecology, marine biology, atmospheric chemistry, and long-term climate change. PolarTREC is funded by the National Science Foundation. While in the field, teachers and researchers communicate extensively with their colleagues, communities, and hundreds of students of all ages across the globe, using a variety of communication technologies and tools to appeal to broad student and public engagement in polar science. Through the PolarTREC website (www.polartrec.com) teachers connect from the field through the use of online journals and forums, photo galleries, podcasts, and learning resources. "Live from IPY," a key activity of PolarTREC, is a free, interactive, distance-learning experience that virtually transports students and the public to unique and remote polar locations through a live Internet interface. Rather than relying solely on the asynchronous elements of online journals, forums, photo albums, and podcasts, "Live from IPY" allows real-time interaction by adding elements including live voice, video, chat, application sharing, polling, and whiteboards, but requires only telephone and/or Internet access for participants and presenters to connect. "Live from IPY" and the online outreach elements of PolarTREC convey the excitement of polar research experiences to a broad audience far beyond the classrooms of the PolarTREC teachers, allowing anyone to join a global network of scientists, teachers, students, and communities and actively participate in the

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

What Controls the Arctic Lower Stratosphere Temperature?

Science.gov (United States)

Newman, Paul A.; Nash, Eric R.; Einaudi, Franco (Technical Monitor)

2001-01-01

The temperature of the Arctic lower stratosphere is critical for understanding polar ozone levels. As temperatures drop below about 195 K, polar stratospheric clouds form, which then convert HCl and ClONO2 into reactive forms that are catalysts for ozone loss reactions. Hence, the lower stratospheric temperature during the March period is a key parameter for understanding polar ozone losses. The temperature is basically understood to be a result of planetary waves which drive the polar temperature away from a cold "radiative equilibrium" state. This is demonstrated using NCEP/NCAR reanalysis calculations of the heat flux and the mean polar temperature. The temperature during the March period is fundamentally driven by the integrated impact of large scale waves moving from the troposphere to the stratosphere during the January through February period. We will further show that the recent cold years in the northern polar vortex are a result of this weakened wave driving of the stratosphere.

Science Partnerships for a Sustainable Arctic: the Marine Mammal Nexus (Invited)

Science.gov (United States)

Moore, S. E.

2010-12-01

Marine mammals are both icons of Arctic marine ecosystems and fundamental to Native subsistence nutrition and culture. Eight species are endemic to the Pacific Arctic, including the polar bear, walrus, ice seals (4 species), beluga and bowhead whales. Studies of walrus and bowheads have been conducted over the past 30 years, to estimate population size and elucidate patterns of movement and abundance. With regard to the three pillars of the SEARCH program, these long-term OBSERVATIONS provide a foundation for research seeking to UNDERSTAND and RESPOND to the effects of rapid climate change on the marine ecosystem. Specifically, research on the coastal ecosystem near Barrow, Alaska focuses on late-summer feeding habitat for bowheads in an area where whales are hunted in autumn. This work is a partnership among agency, academic and local scientists and the residents of Barrow, all of whom seek to better UNDERSTAND how recent dramatic changes in sea ice, winds and offshore industrial activities influence whale movements and behavior. In regard to RESPONDING to climate change, the nascent Sea Ice for Walrus Outlook (SIWO) is a science partnership that projects sea ice and wind conditions for five villages in the Bering Strait region. The objective of the SIWO is to provide information on physical conditions in the marine environment at spatial and temporal scales relevant to walrus hunters. Marine mammals are a strong and dynamic nexus for partnerships among scientists, Arctic residents, resource managers and the general public - as such, they are essential elements to any science plan for a sustainable Arctic.

Implications of rapid environmental change for polar bear behavior and sociality

Science.gov (United States)

Atwood, Todd C.

2017-01-01

Historically, the Arctic sea ice has functioned as a structural barrier that has limited the nature and extent of interactions between humans and polar bears (Ursus maritimus). However, declining sea ice extent, brought about by global climate change, is increasing the potential for human-polar bear interactions. Loss of sea ice habitat is driving changes to both human and polar bear behavior—it is facilitating increases in human activities (e.g., offshore oil and gas exploration and extraction, trans-Arctic shipping, recreation), while also causing the displacement of bears from preferred foraging habitat (i.e., sea ice over biologically productive shallow) to land in some portions of their range. The end result of these changes is that polar bears are spending greater amounts of time in close proximity to people. Coexistence between humans and polar bears will require imposing mechanisms to manage further development, as well as mitigation strategies that reduce the burden to local communities.

The polar mesosphere

International Nuclear Information System (INIS)

Morris, Ray; Murphy, Damian

2008-01-01

The mesosphere region, which lies at the edge of space, contains the coldest layer of the Earth's atmosphere, with summer temperatures as low as minus 130 °C. In this extreme environment ice aerosol layers have appeared since the dawn of industrialization—whose existence may arguably be linked to human influence—on yet another layer of the Earth's fragile atmosphere. Ground-based and space-based experiments conducted in the Arctic and Antarctic during the International Polar Year (IPY) aim to address limitations in our knowledge and to advance our understanding of thermal and dynamical processes at play in the polar mesosphere

Scientific Participation at the Poles: K-12 Teachers in Polar Science for Careers and Classrooms

Science.gov (United States)

Crowley, S.; Warburton, J.

2012-12-01

PolarTREC (Teachers and Researchers Exploring and Collaborating) is a National Science Foundation (NSF) funded program in which K-12 teachers participate in hands-on field research experiences in the polar regions. PolarTREC highlights the importance of involving teachers in scientific research in regards to their careers as educators and their ability to engage students in the direct experience of science. To date, PolarTREC has placed over 90 teachers with research teams in the Arctic and Antarctic. Published results of our program evaluation quantify the effect of the field experience on the teachers' use of the real scientific process in the classroom, the improvement in science content taught in classrooms, and the use of non-fiction texts (real data and science papers) as primary learning tools for students. Teachers and students both report an increase of STEM literacy in the classroom content, confidence in science education, as well as a markedly broadened outlook of science as essential to their future. Research conducted with science teams affirms that they are achieving broader impacts when PolarTREC teachers are involved in their expeditions. Additionally, they reported that these teachers making vital contributions to the success of the scientific project.

Black Carbon in Arctic Snow: Preliminary Results from Recent Field Measurements

Science.gov (United States)

Warren, S. G.; Grenfell, T. C.; Radionov, V. F.; Clarke, A. D.

2007-12-01

Annual snowpacks act to amplify variations in regional solar heating of the surface due to positive feedback processes associated with areal melting and precipitation. Small amounts of black carbon (BC) in the snow can reduce the albedo and modulate shortwave absorption and transmission affecting the onset of melt and heating of the snow pack. The effect of black carbon on the albedo of snow in the Arctic is estimated to be up to a few percent. The only prior survey of arctic snow was that of Clarke and Noone in 1983-84. We have begun a wide- area survey of the BC content of arctic snow in order to update and expand the 1983/84 survey. Samples of snow have been collected in mid to late spring when the entire winter snowpack was accessible. The samples have been melted and filtered, and the filters analyzed for absorptive impurities. To date, sites in Alaska, Canada, Greenland, and in the Arctic Basin have been sampled. In March and April 2007 we also carried out a field program at four sites in northwestern Russia as part of the International Polar Year. Preliminary results based on visual comparison with the standard filters indicate that the snow cover in arctic North America and the Beaufort Sea have lower BC concentrations now than 20 years ago while levels in Greenland are about the same. Background levels of BC in Russia are approximately twice those in North America consistent with modeling predictions of Flanner et al., 2007. More accurate values of absorption will be obtained by measurement of spectral transmission of the filters, which will also allow the relative contributions of BC and soil dust to be determined.

Sexual Polarities: Shelley’s Frankenstein and Polar Exploration as a Search for Origins Beyond ‘woman’

Directory of Open Access Journals (Sweden)

Polly Gould

2008-02-01

Full Text Available This paper is about our parents and our predecessors in life and in literature. It specifically interrogates the choice of Polar landscapes for the playing out of narratives of gender difference in stories of Arctic and Antarctic exploration. I have chosen to pay attention to three narratives: Shackleton's South, Mary Shelley's Frankenstein and Ursula Le Guin's short story Sur. They all take place in the icy expanse of the Arctic and Antarctic. I will read them in the light of the question of origins: ‘where do I come from?'

Improving Geoscience Education through the PolarTREC Teacher Research Experience Model (Invited)

Science.gov (United States)

Warburton, J.; Timm, K.; Larson, A. M.

2010-12-01

Teacher Research Experiences (TRE’s) are not new. For more than a decade, the National Science Foundation (NSF) as well as other federal agencies have been funding programs that place teachers with researchers in efforts to invigorate science education by bringing educators and researchers together through hands-on experiences. Many of the TRE’s are successful in providing a hands-on field experience for the teachers and researchers however many of the programs lack the resources to continue the collaborations and support the growing network of teachers that have had these field experiences. In 2007, NSF provided funding for PolarTREC—Teachers and Researchers Exploring and Collaborating, a program of the Arctic Research Consortium of the U.S. (ARCUS). PolarTREC is a TRE where K-12 teachers participate in polar field research, working closely with scientists as a pathway to improving science education. In just three years, it has become a successful TRE. What makes PolarTREC different than other the teacher research experience programs and how can others benefit from what we have learned? During this presentation, we will share data collected through the program evaluation and on how PolarTREC contributes to the discipline of Science, Technology, Engineering, and Mathematics (STEM) education and pedagogy through a model program conceived and organized according to current best practices, such as pre-research training, mentoring, support for classroom transfer, and long-term access to resources and support. Data shows that PolarTREC’s comprehensive program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes in key areas including amount of time spent in school exploring research activities, importance of understanding science for future work, importance of understanding the polar regions as a person

What are the toxicological effects of mercury in Arctic biota?

DEFF Research Database (Denmark)

Dietz, Rune; Sonne, Christian; Basu, Niladri

2013-01-01

effects. Species whose concentrations exceed threshold values include the polar bears (Ursus maritimus), beluga whale (Delphinapterus leucas), pilot whale (Globicephala melas), hooded seal (Cystophora cristata), a few seabird species, and landlocked Arctic char (Salvelinus alpinus). Toothed whales appear...

Changes in Arctic and Antarctic Sea Ice as a Microcosm of Global Climate Change

Science.gov (United States)

Parkinson, Claire L.

2014-01-01

Polar sea ice is a key element of the climate system and has now been monitored through satellite observations for over three and a half decades. The satellite observations reveal considerable information about polar ice and its changes since the late 1970s, including a prominent downward trend in Arctic sea ice coverage and a much lesser upward trend in Antarctic sea ice coverage, illustrative of the important fact that climate change entails spatial contrasts. The decreasing ice coverage in the Arctic corresponds well with contemporaneous Arctic warming and exhibits particularly large decreases in the summers of 2007 and 2012, influenced by both preconditioning and atmospheric conditions. The increasing ice coverage in the Antarctic is not as readily explained, but spatial differences in the Antarctic trends suggest a possible connection with atmospheric circulation changes that have perhaps been influenced by the Antarctic ozone hole. The changes in the polar ice covers and the issues surrounding those changes have many commonalities with broader climate changes and their surrounding issues, allowing the sea ice changes to be viewed in some important ways as a microcosm of global climate change.

The greenhouse effect and the Arctic ice

International Nuclear Information System (INIS)

Groenaas, Sigbjoern

2002-01-01

The impact on the Arctic ice of global warming is important for many people and for the environment. Less ice means changed conditions for the Inuits, hard times for the polar bears and changed conditions for the fishing sector. There is at present some uncertainty about the thickness of the ice and what might be the cause of its oscillation. It was reported a few years ago that the thickness of the ice had almost been reduced by 50 per cent since the 1950s and some researchers suggested that within a few decades the ice would disappear during the summer. These measurements have turned out not to be representative for the whole Arctic region, and it now appears that a great deal of the measured thickness variation can be attributed to changes in the atmospheric circulation. The article discusses the Arctic Oscillation and the North Atlantic Oscillation in relation to the ice thickness, and climate models. Feedback mechanisms such as reduced albedo may have a big impact in the Arctic in a global greenhouse warming. Model simulations are at variance, and the scenarios for the future are uncertain

Sources and sinks of carbon dioxide in the Arctic regions

Energy Technology Data Exchange (ETDEWEB)

Gosink, T. A.; Kelley, J. J.

1982-01-01

The data base required to adequately ascertain seasonal source and sink strengths in the arctic regions is difficult to obtain. However, there are now a reasonable quantity of data for this polar region to estimate sources and sinks within the Arctic which may contribute significantly to the annual tropospheric CO/sub 2/ concentration fluctuation. The sea-ice-air and the sea-air interfaces account for most of the contribution to the sources and sinks for carbon dioxide. Although the arctic and subarctic region is small in extent, it certainly is not impervious and ice sealed. Our estimate, based on historical data and current research, indicates that the Arctic, which is about 4% of the earth's surface, is an annual net sink for approx. 10/sup 15/ g CO/sub 2/ accounting for an equivalent of approx. 3% of the annual anthropogenic contribution of CO/sub 2/ to the troposphere.

One-dimensional heat conduction equation of the polar bear hair

Directory of Open Access Journals (Sweden)

Zhu Wei-Hong

2015-01-01

Full Text Available Hairs of a polar bear (Ursus maritimus possess special membrane-pore structure. The structure enables the polar bear to survive in the harsh Arctic regions. In this paper, the membrane-pore structure be approximately considered as fractal space, 1-D heat conduction equation of the polar bear hair is established and the solution of the equation is obtained.

High contributions of sea ice derived carbon in polar bear (Ursus maritimus) tissue.

Science.gov (United States)

Brown, Thomas A; Galicia, Melissa P; Thiemann, Gregory W; Belt, Simon T; Yurkowski, David J; Dyck, Markus G

2018-01-01

Polar bears (Ursus maritimus) rely upon Arctic sea ice as a physical habitat. Consequently, conservation assessments of polar bears identify the ongoing reduction in sea ice to represent a significant threat to their survival. However, the additional role of sea ice as a potential, indirect, source of energy to bears has been overlooked. Here we used the highly branched isoprenoid lipid biomarker-based index (H-Print) approach in combination with quantitative fatty acid signature analysis to show that sympagic (sea ice-associated), rather than pelagic, carbon contributions dominated the marine component of polar bear diet (72-100%; 99% CI, n = 55), irrespective of differences in diet composition. The lowest mean estimates of sympagic carbon were found in Baffin Bay bears, which were also exposed to the most rapidly increasing open water season. Therefore, our data illustrate that for future Arctic ecosystems that are likely to be characterised by reduced sea ice cover, polar bears will not only be impacted by a change in their physical habitat, but also potentially in the supply of energy to the ecosystems upon which they depend. This data represents the first quantifiable baseline that is critical for the assessment of likely ongoing changes in energy supply to Arctic predators as we move into an increasingly uncertain future for polar ecosystems.

NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Polar Winds from NDE

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains the Level 3 Polar Winds Northern and Southern Hemisphere datasets. The Level 3 Polar Winds data from VIIRS for the Arctic and Antarctic from 65...

Biogeography of photoautotrophs in the high polar biome

Directory of Open Access Journals (Sweden)

Stephen Brian Pointing

2015-09-01

Full Text Available The global latitudinal gradient in biodiversity weakens in the high polar biome and so an alternative explanation for distribution of Arctic and Antarctic photoautotrophs is required. Here we identify how temporal, microclimate and evolutionary drivers of biogeography are important, rather than the macroclimate features that drive plant diversity patterns elsewhere. High polar ecosystems are biologically unique, with a more central role for bryophytes, lichens and microbial photoautotrophs over that of vascular plants. Constraints on vascular plants arise mainly due to stature and ontogenetic barriers. Conversely non-vascular plant and microbial photoautotroph distribution is correlated with favourable microclimates and the capacity for poikilohydric dormancy. Contemporary distribution also depends on evolutionary history, with adaptive and dispersal traits as well as legacy influencing biogeography. We highlight the relevance of these findings to predicting future impacts on polar plant diversity and to the current status of plants in Arctic and Antarctic conservation policy frameworks.

Polar On-Line Acquisition Relay and Transmission System (POLARATS)

Energy Technology Data Exchange (ETDEWEB)

Yuracko, K.

2004-07-15

POLARATS (Polar On-Line Acquisition Relay And Transmission System) is being developed by YAHSGS LLC (YAHSGS) and Oak Ridge National Laboratory (ORNL) to provide remote, unattended monitoring of environmental parameters under harsh environmental conditions. In particular, instrumental design and engineering is oriented towards protection of human health in the Arctic, and with the additional goal of advancing Arctic education and research. POLARATS will obtain and transmit environmental data from hardened monitoring devices deployed in locations important to understanding atmospheric and aquatic pollutant migration as it is biomagnified in Arctic food chains. An Internet- and personal computer (PC)-based educational module will provide real time sensor data, on-line educational content, and will be integrated with workbooks and textbooks for use in middle and high school science programs. The educational elements of POLARATS include an Internet-based educational module that will instruct students in the use of the data and how those data fit into changing Arctic environments and food chains. POLARATS will: (1) Enable students, members of the community, and scientific researchers to monitor local environmental conditions in real time over the Internet; and (2) Provide additional educational benefits through integration with middle- and high-school science curricula. Information will be relayed from POLARATS devices to classrooms and libraries along with custom-designed POLARATS teaching materials that will be integrated into existing curricula to enhance the educational benefits realized from the information obtained.

The Norwegian Radiation Protection Authority's Environmental Unit - 10 years in the Polar Environmental Centre, Tromsoe

International Nuclear Information System (INIS)

2009-01-01

The Norwegian Radiation Protection Authority (NRPA) established an Environmental Unit at the Polar Environmental Centre in Tromsoe in the summer of 1999. The aim of establishing the unit in Tromsoe was to further the monitoring programmes of the NRPA in the Arctic and to the promote collaboration within the Polar Environmental Centre. Over the last 10 years, the NRPA's Environmental Unit has undertaken a range of research and monitoring activities in close cooperation with other institutes in the Polar Environmental Centre that have helped to further understand the current radiological status of the Norwegian Arctic. (Author)

Tsunami in the Arctic

Science.gov (United States)

Kulikov, Evgueni; Medvedev, Igor; Ivaschenko, Alexey

2017-04-01

The severity of the climate and sparsely populated coastal regions are the reason why the Russian part of the Arctic Ocean belongs to the least studied areas of the World Ocean. In the same time intensive economic development of the Arctic region, specifically oil and gas industry, require studies of potential thread natural disasters that can cause environmental and technical damage of the coastal and maritime infrastructure of energy industry complex (FEC). Despite the fact that the seismic activity in the Arctic can be attributed to a moderate level, we cannot exclude the occurrence of destructive tsunami waves, directly threatening the FEC. According to the IAEA requirements, in the construction of nuclear power plants it is necessary to take into account the impact of all natural disasters with frequency more than 10-5 per year. Planned accommodation in the polar regions of the Russian floating nuclear power plants certainly requires an adequate risk assessment of the tsunami hazard in the areas of their location. Develop the concept of tsunami hazard assessment would be based on the numerical simulation of different scenarios in which reproduced the hypothetical seismic sources and generated tsunamis. The analysis of available geological, geophysical and seismological data for the period of instrumental observations (1918-2015) shows that the highest earthquake potential within the Arctic region is associated with the underwater Mid-Arctic zone of ocean bottom spreading (interplate boundary between Eurasia and North American plates) as well as with some areas of continental slope within the marginal seas. For the Arctic coast of Russia and the adjacent shelf area, the greatest tsunami danger of seismotectonic origin comes from the earthquakes occurring in the underwater Gakkel Ridge zone, the north-eastern part of the Mid-Arctic zone. In this area, one may expect earthquakes of magnitude Mw ˜ 6.5-7.0 at a rate of 10-2 per year and of magnitude Mw ˜ 7.5 at a

U.S. Arctic research in a technological age

International Nuclear Information System (INIS)

Johnson, P.L.

1993-01-01

The United States Arctic Research Commission was established in 1984 primarily as an advisory agency. An Interagency Arctic Research Policy Committee is one of the main recipients of the Commission's recommendations. The Committee formulated an Arctic research policy calling for research focused on national security concerns, regional development with minimal environmental or adverse social impact, and scientific research on Arctic phenomena and processes. In basic science, emphasis is placed on the need to understand Arctic processes as part of the global earth system. These processes include those that affect and are affected by climatic change. A new research program in Arctic systems science has three components: paleoenvironmental studies on ice core from Greenland; ocean-atmosphere interactions; and land-atmosphere interactions. The Commission also recognizes a need to focus on issues relevant to the Arctic as an integral component of the world economic system, since the Arctic is a significant source of petroleum and minerals. The Commission recommended that the Committee develop an Arctic engineering research plan with emphasis on such topics as oil spill prevention, waste disposal, small-scale power generation, and Arctic construction techniques. The USA is also cooperating in international Arctic research through the International Arctic Science Committee, the Arctic Environmental Protection Strategy, and the North Pacific Marine Science Organization

Climate-induced behavioral changes influence exposure of an Arctic apex predator to pathogens and contaminants

Science.gov (United States)

Polar bears (Ursus maritimus) may serve as sentinels for pathogens and contaminants, providing insight into changing Arctic ecosystems and health risks to wildlife and humans. Recent changes in the availability of sea ice habitat have coincided with increased use of land by polar bears from the sout...

Predictability of the 2012 Great Arctic Cyclone on medium-range timescales

Science.gov (United States)

Yamagami, Akio; Matsueda, Mio; Tanaka, Hiroshi L.

2018-03-01

Arctic Cyclones (ACs) can have a significant impact on the Arctic region. Therefore, the accurate prediction of ACs is important in anticipating their associated environmental and societal costs. This study investigates the predictability of the 2012 Great Arctic Cyclone (AC12) that exhibited a minimum central pressure of 964 hPa on 6 August 2012, using five medium-range ensemble forecasts. We show that the development and position of AC12 were better predicted in forecasts initialized on and after 4 August 2012. In addition, the position of AC12 was more predictable than its development. A comparison of ensemble members, classified by the error in predictability of the development and position of AC12, revealed that an accurate prediction of upper-level fields, particularly temperature, was important for the prediction of this event. The predicted position of AC12 was influenced mainly by the prediction of the polar vortex, whereas the predicted development of AC12 was dependent primarily on the prediction of the merging of upper-level warm cores. Consequently, an accurate prediction of the polar vortex position and the development of the warm core through merging resulted in better prediction of AC12.

A Hero in the Friendly Arctic: Deconstructing Vilhjalmur Stefansson's Rhetorical Maneuver

Directory of Open Access Journals (Sweden)

Silje Gaupseth

2012-05-01

Full Text Available The article deals with Arctic explorer and anthropologist Vilhjalmur Stefansson's self-presentation in the expedition account The Friendly Arctic: The Story of Five Years in Polar Regions (1921, which tells the story of his travels and trials in the Canadian High Arctic in the years between 1913-1918. The account has been considered a key text to Stefansson's Arctic career, and provides a textbook example of his characteristic theory of living off the country in the so-called Eskimo way. Against the background of Stefansson's debated position as Arctic expert and visionary, I ask if it is possible to read the kind of criticism with which Stefansson frequently was met as rooted in some of the narrative aspects of his account. The narrative persona or implied author is a central element in the literature of exploration, as several literary scholars have pointed out. My reading is centred around the implied author of The Friendly Arctic, which I argue must be read in light of the sometimes conflicting roles given to Stefansson as protagonist and narrator in his own story. Close-readings of passages from the account raise the dilemma of how it is possible to present oneself as a hero in an essentially friendly Arctic.

Impacts of projected sea ice changes on trans-Arctic navigation

Science.gov (United States)

Stephenson, S. R.; Smith, L. C.

2012-12-01

Reduced Arctic sea ice continues to be a palpable signal of global change. Record lows in September sea ice extent from 2007 - 2011 have fueled speculation that trans-Arctic navigation routes may become physically viable in the 21st century. General Circulation Models project a nearly ice-free Arctic Ocean in summer by mid-century; however, how reduced sea ice will realistically impact navigation is not well understood. Using the ATAM (Arctic Transportation Accessibility Model) we present simulations of 21st-century trans-Arctic voyages as a function of climatic (ice) conditions and vessel class. Simulations are based on sea ice projections for three climatic forcing scenarios (RCP 4.5, 6.0, and 8.5 W/m^2) representing present-day and mid-century conditions, assuming Polar Class 6 (PC6) and open-water vessels (OW) with medium and no ice-breaking capability, respectively. Optimal least-cost routes (minimizing travel time while avoiding ice impassible to a given vessel class) between the North Atlantic and the Bering Strait were calculated for summer months of each time window. While Arctic navigation depends on other factors besides sea ice including economics, infrastructure, bathymetry, current, and weather, these projections should be useful for strategic planning by governments, regulatory and environmental agencies, and the global maritime industry to assess potential changes in the spatial and temporal ranges of Arctic marine operations.

The Arctic Vortex in March 2011: A Dynamical Perspective

Science.gov (United States)

Hurwitz, Margaret M.; Newman, Paul A.; Garfinkel,Chaim I.

2011-01-01

Despite the record ozone loss observed in March 2011, dynamical conditions in the Arctic stratosphere were unusual but not unprecedented. Weak planetary wave driving in February preceded cold anomalies in t he polar lower stratosphere in March and a relatively late breakup of the Arctic vortex in April. La Nina conditions and the westerly phas e of the quasi-biennial oscillation (QBO) were observed in March 201 1. Though these conditions are generally associated with a stronger vortex in mid-winter, the respective cold anomalies do not persist t hrough March. Therefore, the La Nina and QBO-westerly conditions cannot explain the observed cold anomalies in March 2011. In contrast, po sitive sea surface temperature anomalies in the North Pacific may ha ve contributed to the unusually weak tropospheric wave driving and s trong Arctic vortex in late winter 2011.

The Arctic Observing Network (AON)Cooperative Arctic Data and Information Service (CADIS)

Science.gov (United States)

Moore, J.; Fetterer, F.; Middleton, D.; Ramamurthy, M.; Barry, R.

2007-12-01

The Arctic Observing Network (AON) is intended to be a federation of 34 land, atmosphere and ocean observation sites, some already operating and some newly funded by the U.S. National Science Foundation. This International Polar Year (IPY) initiative will acquire a major portion of the data coming from the interagency Study of Environmental Arctic Change (SEARCH). AON will succeed in supporting the science envisioned by its planners only if it functions as a system and not as a collection of independent observation programs. Development and implementation of a comprehensive data management strategy will key a key to the success of this effort. AON planners envision an ideal data management system that includes a portal through which scientists can submit metadata and datasets at a single location; search the complete archive and find all data relevant to a location or process; all data have browse imagery and complete documentation; time series or fields can be plotted on line, and all data are in a relational database so that multiple data sets and sources can be queried and retrieved. The Cooperative Arctic Data and Information Service (CADIS) will provide near-real-time data delivery, a long-term repository for data, a portal for data discovery, and tools to manipulate data by building on existing tools like the Unidata Integrated Data Viewer (IDV). Our approach to the data integration challenge is to start by asking investigators to provide metadata via a general purpose user interface. An entry tool assists PIs in writing metadata and submitting data. Data can be submitted to the archive in NetCDF with Climate and Forecast conventions or in one of several other standard formats where possible. CADIS is a joint effort of the University Corporation for Atmospheric Research (UCAR), the National Snow and Ice Data Center (NSIDC), and the National Center for Atmospheric Research (NCAR). In the first year, we are concentrating on establishing metadata protocols that

(Arbo)viruses in high European Arctic

OpenAIRE

ELSTEROVÁ, Jana

2016-01-01

Since an ongoing climate change covers strongly the polar areas. Higher temperatures and related climate parameters bring the emergence of new parasites and their pathogens to higher latitudes. This may influence zoonotic diseases including arthropod-transmitted diseases. The tick species Ixodes uriae, parasitizing seabirds in the Arctic, may transmit many pathogens including various arboviruses, Borrelia spirochetes and Babesia apicomplexans. In the study we diagnosed 89 individuals of seabi...

Process contributions to the intermodel spread in amplified Arctic warming

Science.gov (United States)

Boeke, R.; Taylor, P. C.

2016-12-01

The Arctic is warming at a rate more than twice the global average. This robust climate system response to an external forcing is referred to as Arctic Amplification (AA). While Coupled Model Intercomparison Project 5 (CMIP5) climate models simulate AA, the largest intermodel spread in projected warming is also found in the Arctic. Quantifying the amount of polar warming relative to global warming influences how society adapts to climate change; a 2°C increase in global mean temperature would result in a polar warming between 4-8°C according to the intermodel spread in CMIP5 simulations. A trove of previous work has considered AA diagnostically using variations in the surface energy budget to attribute the intermodel spread in AA to an assortment of feedbacks—surface albedo, cloud, surface turbulent flux, and atmospheric and oceanic energy transport. We consider a systems-thinking approach treating AA as a process that evolves over time. We hypothesize that two specific components of the AA process are most important and influence the intermodel spread. (1) The inability of the Arctic system to effectively remove excess heat sourced from natural variability. The change in the efficiency of the `Arctic air conditioner' is thought to be due to thinner and less extensive sea ice and the resulting ice albedo feedback. (2) The process through which energy is stored in the ocean and exchanged with the atmosphere within the context of the sea ice annual cycle is also important. This study uses CMIP5 simulations from the historical and RCP8.5 (Representative Concentration Pathway; an emission scenario with forcing increasing to 8.5 W m-2 by 2100) to analyze how the AA process operates in present and future climate. The intermodel spread in these processes and the influence on the spread in AA are discussed. This approach identifies models that more realistically simulate the AA process and will aid in narrowing intermodel spread in Arctic surface temperature

A cluster of three cases of trichinellosis linked to bear meat consumption in the Arctic

DEFF Research Database (Denmark)

Dupouy-Camet, Jean; Yera, Hélène; Dahane, Naïma

2016-01-01

We report here three cases of trichinellosis due to polar bear meat consumption in East Greenland. In the past 20 years, 31 cases of trichinellosis have been reported in French travellers to the Arctic (North Quebec, Nunavut and Greenland) who consumed undercooked meat from black, brown, or polar...

Test and Evaluation of CGC POLAR STAR WAGB 10. Volume III. Background.

Science.gov (United States)

1978-09-01

through Solid Ice," Problems of the Arctic and Antartic No. 5. Smith, N., (1969), "Determining the Dynamic Properties of Snow and Ice by Forced Valuation...Experiments," Thesis, Arctic and Antartic Institute, Leningrad. Voelker, R.P., and Koch, E., (1968), "The Design of a Ship’s Control Space in Polar Icebreakers

The Rapid Arctic Warming and Its Impact on East Asian Winter Weather in Recent Decade

Science.gov (United States)

Kim, S. J.; Kim, B. M.; Kim, J. H.

2015-12-01

The Arctic is warming much more rapidly than the lower latitudes. In contrast to the rapid Arctic warming, in winters of the recent decade, the cold-air outbreaks over East Asia occur more frequently and stronger than in 1990s. By accompanying the snow over East Asia, the strong cold surges have led to a severe socio-economic impact. Such severe cold surges in recent decade over east Asia is consistent with the more dominant negative phase of the Arctic Oscillation (AO), that may be attributed by the Arctic amplification. In both observation-based reanalysis and numerical model experiments, the Arctic sea ice melting leads to the weakening of the AO polarity by reducing the meridional temperature gradient through a heat flux feedback. The Arctic warming and associated sea ice melting over the Kara-Barents area in late fall and early winter first release a lot of heat to the atmosphere from the ocean by a strong contrast in temperature and moisture and higher height anomaly is developed over the Kara/Barents and the Ural mountains The anomalous anticyclonic anomaly over the Arctic strengthen the Siberian High and at the same time the east Asian trough is developed over the western coast of the North Pacific. Through the passage between the margin of the Siberian High and east Asian tough, an extremely cold air is transported from east Siberia to east Asia for sometimes more than a week. Such a severe sold air brings about the moisture from nearby ocean, largely influencing the daily lives and economy in north East China, Korea, and Japan. The recent Arctic and associated sea ice melting is not only contributed to the local climate and weather, but also a severe weather in mid-latitudes through a modulation in polar vortex.

Sea Ice Charts of the Russian Arctic in Gridded Format, 1933-2006

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Arctic and Antarctic Research Institute (AARI) in St. Petersburg, Russia, produces sea ice charts for safety of navigation in the polar regions and for other...

Transport Regimes of Air Masses Affecting the Tropospheric Composition of the Canadian and European Arctic During RACEPAC 2014 and NETCARE 2014/2015

Science.gov (United States)

Bozem, H.; Hoor, P. M.; Koellner, F.; Kunkel, D.; Schneider, J.; Schulz, C.; Herber, A. B.; Borrmann, S.; Wendisch, M.; Ehrlich, A.; Leaitch, W. R.; Willis, M. D.; Burkart, J.; Thomas, J. L.; Abbatt, J.

2015-12-01

The Arctic is warming much faster than any other place in the world and undergoes a rapid change dominated by a changing climate in this region. The impact of polluted air masses traveling to the Arctic from various remote sources significantly contributes to the observed climate change, in contrast there are additional local emission sources contributing to the level of pollutants (trace gases and aerosol). Processes affecting the emission and transport of these pollutants are not well understood and need to be further investigated. We present aircraft based trace gas measurements in the Arctic during RACEPAC (2014) and NETCARE (2014 and 2015) with the Polar 6 aircraft of Alfred Wegener Institute (AWI) covering an area from 134°W to 17°W and 68°N to 83°N. We focus on cloud, aerosol and general transport processes of polluted air masses into the high Arctic. Based on CO and CO2 measurements and kinematic 10-day back trajectories we analyze the transport regimes prevalent during spring (RACEPAC 2014 and NETCARE 2015) and summer (NETCARE 2014) in the observed region. Whereas the eastern part of the Canadian Arctic is affected by air masses with their origin in Asia, in the central and western parts of the Canadian and European Arctic air masses from North America are predominant at the time of the measurement. In general the more northern parts of the Arctic were relatively unaffected by pollution from mid-latitudes since air masses mostly travel within the polar dome, being quite isolated. Associated mixing ratios of CO and CO2 fit into the seasonal cycle observed at NOAA ground stations throughout the Arctic, but show a more mid-latitudinal characteristic at higher altitudes. The transition is remarkably sharp and allows for a chemical definition of the polar dome. At low altitudes, synoptic disturbances transport polluted air masses from mid-latitudes into regions of the polar dome. These air masses contribute to the Arctic pollution background, but also

High contributions of sea ice derived carbon in polar bear (Ursus maritimus tissue.

Directory of Open Access Journals (Sweden)

Thomas A Brown

Full Text Available Polar bears (Ursus maritimus rely upon Arctic sea ice as a physical habitat. Consequently, conservation assessments of polar bears identify the ongoing reduction in sea ice to represent a significant threat to their survival. However, the additional role of sea ice as a potential, indirect, source of energy to bears has been overlooked. Here we used the highly branched isoprenoid lipid biomarker-based index (H-Print approach in combination with quantitative fatty acid signature analysis to show that sympagic (sea ice-associated, rather than pelagic, carbon contributions dominated the marine component of polar bear diet (72-100%; 99% CI, n = 55, irrespective of differences in diet composition. The lowest mean estimates of sympagic carbon were found in Baffin Bay bears, which were also exposed to the most rapidly increasing open water season. Therefore, our data illustrate that for future Arctic ecosystems that are likely to be characterised by reduced sea ice cover, polar bears will not only be impacted by a change in their physical habitat, but also potentially in the supply of energy to the ecosystems upon which they depend. This data represents the first quantifiable baseline that is critical for the assessment of likely ongoing changes in energy supply to Arctic predators as we move into an increasingly uncertain future for polar ecosystems.

A lunar polar expedition

Science.gov (United States)

Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

1992-09-01

Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

Warm Arctic—cold continents: climate impacts of the newly open Arctic Sea

Directory of Open Access Journals (Sweden)

James E. Overland

2011-12-01

Full Text Available Recent Arctic changes are likely due to coupled Arctic amplification mechanisms with increased linkage between Arctic climate and sub-Arctic weather. Historically, sea ice grew rapidly in autumn, a strong negative radiative feedback. But increased sea-ice mobility, loss of multi-year sea ice, enhanced heat storage in newly sea ice-free ocean areas, and modified wind fields form connected positive feedback processes. One-way shifts in the Arctic system are sensitive to the combination of episodic intrinsic atmospheric and ocean variability and persistent increasing greenhouse gases. Winter 2009/10 and December 2010 showed a unique connectivity between the Arctic and more southern weather patterns when the typical polar vortex was replaced by high geopotential heights over the central Arctic and low heights over mid-latitudes that resulted in record snow and low temperatures, a warm Arctic—cold continents pattern. The negative value of the winter (DJF 2009/10 North Atlantic Oscillation (NAO index associated with enhanced meridional winds was the lowest observed value since the beginning of the record in 1865. Wind patterns in December 2007 and 2008 also show an impact of warmer Arctic temperatures. A tendency for higher geopotential heights over the Arctic and enhanced meridional winds are physically consistent with continued loss of sea ice over the next 40 years. A major challenge is to understand the interaction of Arctic changes with climate patterns such as the NAO, Pacific North American and El Niño–Southern Oscillation.

Humidity estimate for the middle Eocene Arctic rain forest

Science.gov (United States)

Jahren, A. Hope; Silveira Lobo Sternberg, Leonel

2003-05-01

The exquisite preservation of fossilized Metasequoia trees that grew near 80°N latitude during the middle Eocene (ca. 45 Ma) in Nunavut, Canada, allowed for δD and δ18O analyses of cellulose, techniques previously restricted to wood <30,000 yr old. From the isotopic results, we determined that the middle Eocene Arctic atmosphere contained ˜2× the water found in the region's atmosphere today. This water vapor contributed to a middle Eocene greenhouse effect that insulated the polar region during dark polar winters.

Net Ecosystem Exchange of CO2 with Rapidly Changing High Arctic Landscapes

Science.gov (United States)

Emmerton, C. A.

2015-12-01

High Arctic landscapes are expansive and changing rapidly. However our understanding of their functional responses and potential to mitigate or enhance anthropogenic climate change is limited by few measurements. We collected eddy covariance measurements to quantify the net ecosystem exchange (NEE) of CO2 with polar semidesert and meadow wetland landscapes at the highest-latitude location measured to date (82°N). We coupled these rare data with ground and satellite vegetation production measurements (Normalized Difference Vegetation Index; NDVI) to evaluate the effectiveness of upscaling local to regional NEE. During the growing season, the dry polar semidesert landscape was a near zero sink of atmospheric CO2 (NEE: -0.3±13.5 g C m-2). A nearby meadow wetland accumulated over two magnitudes more carbon (NEE: -79.3±20.0 g C m-2) than the polar semidesert landscape, and was similar to meadow wetland NEE at much more southern latitudes. Polar semidesert NEE was most influenced by moisture, with wetter surface soils resulting in greater soil respiration and CO2 emissions. At the meadow wetland, soil heating enhanced plant growth, which in turn increased CO2 uptake. Our upscaling assessment found that polar semidesert NDVI measured on site was low (mean: 0.120-0.157) and similar to satellite measurements (mean: 0.155-0.163). However, weak plant growth resulted in poor satellite NDVI-NEE relationships and created challenges for remotely-detecting changes in the cycling of carbon on the polar semidesert landscape. The meadow wetland appeared more suitable to assess plant production and NEE via remote-sensing, however high Arctic wetland extent is constrained by topography to small areas that may be difficult to resolve with large satellite pixels. We predict that until summer precipitation and humidity increases substantially, climate-related changes of dry high Arctic landscapes may be restricted by poor soil moisture retention, and therefore have some inertia against

The Arctic Climate Modeling Program: K-12 Geoscience Professional Development for Rural Educators

Science.gov (United States)

Bertram, K. B.

2009-12-01

Helping teachers and students connect with scientists is the heart of the Arctic Climate Modeling Program (ACMP), funded from 2005-09 by the National Science Foundation’s Innovative Technology Experience for Students and Teachers. ACMP offered progressive yearlong science, technology and math (STM) professional development that prepared teachers to train youth in workforce technologies used in Arctic research. ACMP was created for the Bering Strait School District, a geographically isolated area with low standardized test scores, high dropout rates, and poverty. Scientists from around the globe have converged in this region and other areas of the Arctic to observe and measure changes in climate that are significant, accelerating, and unlike any in recorded history. Climate literacy (the ability to understand Earth system science and to make scientifically informed decisions about climate changes) has become essential for this population. Program resources were designed in collaboration with scientists to mimic the processes used to study Arctic climate. Because the Bering Strait School District serves a 98 percent Alaska Native student population, ACMP focused on best practices shown to increase the success of minority students. Significant research indicates that Alaska Native students succeed academically at higher rates when instruction addresses topics of local interest, links education to the students’ physical and cultural environment, uses local knowledge and culture in the curriculum, and incorporates hands-on, inquiry-based lessons in the classroom. A seven-partner consortium of research institutes and Alaska Native corporations created ACMP to help teachers understand their role in nurturing STM talent and motivating students to explore geoscience careers. Research underscores the importance of increasing school emphasis in content areas, such as climate, that facilitate global awareness and civic responsibility, and that foster critical thinking and

An Arctic predator-prey system in flux: climate change impacts on coastal space use by polar bears and ringed seals.

Science.gov (United States)

Hamilton, Charmain D; Kovacs, Kit M; Ims, Rolf A; Aars, Jon; Lydersen, Christian

2017-09-01

Climate change is impacting different species at different rates, leading to alterations in biological interactions with ramifications for wider ecosystem functioning. Understanding these alterations can help improve predictive capacity and inform management efforts designed to mitigate against negative impacts. We investigated how the movement and space use patterns of polar bears (Ursus maritimus) in coastal areas in Svalbard, Norway, have been altered by a sudden decline in sea ice that occurred in 2006. We also investigated whether the spatial overlap between polar bears and their traditionally most important prey, ringed seals (Pusa hispida), has been affected by the sea-ice decline, as polar bears are dependent on a sea-ice platform for hunting seals. We attached biotelemetry devices to ringed seals (n = 60, both sexes) and polar bears (n = 67, all females) before (2002-2004) and after (2010-2013) a sudden decline in sea ice in Svalbard. We used linear mixed-effects models to evaluate the association of these species to environmental features and an approach based on Time Spent in Area to investigate changes in spatial overlap between the two species. Following the sea-ice reduction, polar bears spent the same amount of time close to tidal glacier fronts in the spring but less time in these areas during the summer and autumn. However, ringed seals did not alter their association with glacier fronts during summer, leading to a major decrease in spatial overlap values between these species in Svalbard's coastal areas. Polar bears now move greater distances daily and spend more time close to ground-nesting bird colonies, where bear predation can have substantial local effects. Our results indicate that sea-ice declines have impacted the degree of spatial overlap and hence the strength of the predator-prey relationship between polar bears and ringed seals, with consequences for the wider Arctic marine and terrestrial ecosystems. Shifts in ecological

An assessment of the toxicological significance of anthropogenic contaminants in Canadian arctic wildlife

International Nuclear Information System (INIS)

Fisk, Aaron T.; Wit, Cynthia A. de; Wayland, Mark; Kuzyk, Zou Zou; Burgess, Neil; Letcher, Robert; Braune, Birgit; Norstrom, Ross; Blum, Susan Polischuk; Sandau, Courtney; Lie, Elisabeth; Larsen, Hans Jorgen S.; Skaare, Janneche Utne; Muir, Derek C.G.

2005-01-01

Anthropogenic contaminants have been a concern in the Canadian arctic for over 30 years due to relatively high concentrations of bioaccumulating and biomagnifying organochlorine contaminants (OCs) and toxic metals found in some arctic biota and humans. However, few studies have addressed the potential effects of these contaminants in Canadian arctic wildlife. Prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects related to contaminant exposure, and compares new tissue concentration data to threshold effects levels. Weak relationships between cadmium, mercury and selenium burdens and health biomarkers in common eider ducks (Somateria mollissima borealis) in Nunavut were found but it was concluded that metals were not influencing the health of these birds. Black guillemots (Cepphus grylle) examined near PCB-contaminated Saglek Bay, Labrador, had enlarged livers, elevated EROD and liver lipid levels and reduced retinol (vitamin A) and retinyl palmitate levels, which correlated to PCB levels in the birds. Circulating levels of thyroid hormones in polar bears (Ursus maritimus) were correlated to PCB and HO-PCB plasma concentrations, but the impact at the population level is unknown. High PCB and organochlorine pesticide concentrations were found to be strongly associated with impaired humoral and cell-mediated immune responses in polar bears, implying an increased infection risk that could impact the population. In beluga whale (Delphinapterus leucas), cytochromes P450 (phase I) and conjugating (phase II) enzymes have been extensively profiled (immunochemically and catalytically) in liver, demonstrating the importance of contaminants in relation to enzyme induction, metabolism and potential contaminant bioactivation and fate. Concentrations of OCs and metals in arctic terrestrial wildlife, fish and seabirds are generally below effects thresholds

An assessment of the toxicological significance of anthropogenic contaminants in Canadian arctic wildlife

Energy Technology Data Exchange (ETDEWEB)

Fisk, Aaron T. [Warnell School of Forest Resources, University of Georgia, Athens, GA 30602-2152 (United States)]. E-mail: afisk@forestry.uga.edu; Wit, Cynthia A. de [Department of Applied Environmental Science, Stockholm University, Stockholm (Sweden); Wayland, Mark [Prairie and Northern Wildlife Research Centre, Environment Canada, 115 Perimeter Rd., Saskatoon, SK, S7N 0X4 (Canada); Kuzyk, Zou Zou [Environmental Sciences Group, Royal Military College of Canada, Kingston, ON, K7K 7B4 (Canada); Burgess, Neil [Canadian Wildlife Service, Environment Canada, 6 Bruce St. Mt. Pearl, NL, A1N4T3 (Canada); Letcher, Robert [National Wildlife Research Centre, Environment Canada, Ottawa, ON, K1A 0H3 (Canada); Braune, Birgit [National Wildlife Research Centre, Environment Canada, Ottawa, ON, Canada K1A 0H3 (Canada); Norstrom, Ross [National Wildlife Research Centre, Environment Canada, Ottawa, ON, K1A 0H3 (Canada); Blum, Susan Polischuk [Office of Research Services, University of Saskatchewan, Saskatoon, SK, S7N 4J8 (Canada); Sandau, Courtney [Jacques Whitford Limited, Calgary, AB, T2R 0E4 (Canada); Lie, Elisabeth [National Veterinary Institute, P.O. Box 8156, Dep 0033, Oslo (Norway); Larsen, Hans Jorgen S. [Norwegian School of Veterinary Science, P.O. Box 8146, Dep 0033, Oslo (Norway); Skaare, Janneche Utne [National Veterinary Institute, P.O. Box 8156, Dep 0033, Oslo (Norway); Norwegian School of Veterinary Science, P.O. Box 8146, Dep 0033, Oslo (Norway); Muir, Derek C.G. [National Water Research Institute, Environment Canada, Burlington, ON, L7R 4A6 (Canada)

2005-12-01

Anthropogenic contaminants have been a concern in the Canadian arctic for over 30 years due to relatively high concentrations of bioaccumulating and biomagnifying organochlorine contaminants (OCs) and toxic metals found in some arctic biota and humans. However, few studies have addressed the potential effects of these contaminants in Canadian arctic wildlife. Prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects related to contaminant exposure, and compares new tissue concentration data to threshold effects levels. Weak relationships between cadmium, mercury and selenium burdens and health biomarkers in common eider ducks (Somateria mollissima borealis) in Nunavut were found but it was concluded that metals were not influencing the health of these birds. Black guillemots (Cepphus grylle) examined near PCB-contaminated Saglek Bay, Labrador, had enlarged livers, elevated EROD and liver lipid levels and reduced retinol (vitamin A) and retinyl palmitate levels, which correlated to PCB levels in the birds. Circulating levels of thyroid hormones in polar bears (Ursus maritimus) were correlated to PCB and HO-PCB plasma concentrations, but the impact at the population level is unknown. High PCB and organochlorine pesticide concentrations were found to be strongly associated with impaired humoral and cell-mediated immune responses in polar bears, implying an increased infection risk that could impact the population. In beluga whale (Delphinapterus leucas), cytochromes P450 (phase I) and conjugating (phase II) enzymes have been extensively profiled (immunochemically and catalytically) in liver, demonstrating the importance of contaminants in relation to enzyme induction, metabolism and potential contaminant bioactivation and fate. Concentrations of OCs and metals in arctic terrestrial wildlife, fish and seabirds are generally below effects thresholds

AMBON - the Arctic Marine Biodiversity Observing Network

Science.gov (United States)

Iken, K.; Danielson, S. L.; Grebmeier, J. M.; Cooper, L. W.; Hopcroft, R. R.; Kuletz, K.; Stafford, K.; Mueter, F. J.; Collins, E.; Bluhm, B.; Moore, S. E.; Bochenek, R. J.

2016-02-01

The goal of the Arctic Marine Biodiversity Observing Network (AMBON) is to build an operational and sustainable marine biodiversity observing network for the US Arctic Chukchi Sea continental shelf. The AMBON has four main goals: 1. To close current gaps in taxonomic biodiversity observations from microbes to whales, 2. To integrate results of past and ongoing research programs on the US Arctic shelf into a biodiversity observation network, 3. To demonstrate at a regional level how an observing network could be developed, and 4. To link with programs on the pan-Arctic to global scale. The AMBON fills taxonomic (from microbes to mammals), functional (food web structure), spatial and temporal (continuing time series) gaps, and includes new technologies such as state-of-the-art genomic tools, with biodiversity and environmental observations linked through central data management through the Alaska Ocean Observing System. AMBON is a 5-year partnership between university and federal researchers, funded through the National Ocean Partnership Program (NOPP), with partners in the National Oceanographic and Atmospheric Administration (NOAA), the Bureau of Ocean and Energy Management (BOEM), and Shell industry. AMBON will allow us to better coordinate, sustain, and synthesize biodiversity research efforts, and make data available to a broad audience of users, stakeholders, and resource managers.

Airborne contaminants in the Arctic: What we need to know

International Nuclear Information System (INIS)

Landers, D.H.; Bangay, G.; Sisula, H.; Colborn, T.; Liljelund, L.E.

1994-01-01

Arctic contaminant research is expensive and current international resources are restricted. It is incumbent upon current and future arctic research programs to focus efforts where the greatest and most relevant information can be gained. This paper is an attempt to help guide future work to focus on the most pressing information needs. Several summary points are related to environmental research in the Arctic; some may also relate to environmental research outside the Arctic

Environment, vegetation and greenness (NDVI) along the North America and Eurasia Arctic transects

International Nuclear Information System (INIS)

Walker, D A; Raynolds, M K; Kuss, P; Kade, A N; Epstein, H E; Frost, G V; Kopecky, M A; Daniëls, F J A; Leibman, M O; Moskalenko, N G; Khomutov, A V; Matyshak, G V; Khitun, O V; Forbes, B C; Bhatt, U S; Vonlanthen, C M; Tichý, L

2012-01-01

Satellite-based measurements of the normalized difference vegetation index (NDVI; an index of vegetation greenness and photosynthetic capacity) indicate that tundra environments are generally greening and becoming more productive as climates warm in the Arctic. The greening, however, varies and is even negative in some parts of the Arctic. To help interpret the space-based observations, the International Polar Year (IPY) Greening of the Arctic project conducted ground-based surveys along two >1500 km transects that span all five Arctic bioclimate subzones. Here we summarize the climate, soil, vegetation, biomass, and spectral information collected from the North America Arctic transect (NAAT), which has a more continental climate, and the Eurasia Arctic transect (EAT), which has a more oceanic climate. The transects have broadly similar summer temperature regimes and overall vegetation physiognomy, but strong differences in precipitation, especially winter precipitation, soil texture and pH, disturbance regimes, and plant species composition and structure. The results indicate that summer warmth and NDVI increased more strongly along the more continental transect. (letter)

Collaborations for Arctic Sea Ice Information and Tools

Science.gov (United States)

Sheffield Guy, L.; Wiggins, H. V.; Turner-Bogren, E. J.; Rich, R. H.

2017-12-01

The dramatic and rapid changes in Arctic sea ice require collaboration across boundaries, including between disciplines, sectors, institutions, and between scientists and decision-makers. This poster will highlight several projects that provide knowledge to advance the development and use of sea ice knowledge. Sea Ice for Walrus Outlook (SIWO: https://www.arcus.org/search-program/siwo) - SIWO is a resource for Alaskan Native subsistence hunters and other interested stakeholders. SIWO provides weekly reports, during April-June, of sea ice conditions relevant to walrus in the northern Bering and southern Chukchi seas. Collaboration among scientists, Alaskan Native sea-ice experts, and the Eskimo Walrus Commission is fundamental to this project's success. Sea Ice Prediction Network (SIPN: https://www.arcus.org/sipn) - A collaborative, multi-agency-funded project focused on seasonal Arctic sea ice predictions. The goals of SIPN include: coordinate and evaluate Arctic sea ice predictions; integrate, assess, and guide observations; synthesize predictions and observations; and disseminate predictions and engage key stakeholders. The Sea Ice Outlook—a key activity of SIPN—is an open process to share and synthesize predictions of the September minimum Arctic sea ice extent and other variables. Other SIPN activities include workshops, webinars, and communications across the network. Directory of Sea Ice Experts (https://www.arcus.org/researchers) - ARCUS has undertaken a pilot project to develop a web-based directory of sea ice experts across institutions, countries, and sectors. The goal of the project is to catalyze networking between individual investigators, institutions, funding agencies, and other stakeholders interested in Arctic sea ice. Study of Environmental Arctic Change (SEARCH: https://www.arcus.org/search-program) - SEARCH is a collaborative program that advances research, synthesizes research findings, and broadly communicates the results to support

Arctic and Antarctic Sea Ice Changes and Impacts (Invited)

Science.gov (United States)

Nghiem, S. V.

2013-12-01

The extent of springtime Arctic perennial sea ice, important to preconditioning summer melt and to polar sunrise photochemistry, continues its precipitous reduction in the last decade marked by a record low in 2012, as the Bromine, Ozone, and Mercury Experiment (BROMEX) was conducted around Barrow, Alaska, to investigate impacts of sea ice reduction on photochemical processes, transport, and distribution in the polar environment. In spring 2013, there was further loss of perennial sea ice, as it was not observed in the ocean region adjacent to the Alaskan north coast, where there was a stretch of perennial sea ice in 2012 in the Beaufort Sea and Chukchi Sea. In contrast to the rapid and extensive loss of sea ice in the Arctic, Antarctic sea ice has a trend of a slight increase in the past three decades. Given the significant variability in time and in space together with uncertainties in satellite observations, the increasing trend of Antarctic sea ice may arguably be considered as having a low confidence level; however, there was no overall reduction of Antarctic sea ice extent anywhere close to the decreasing rate of Arctic sea ice. There exist publications presenting various factors driving changes in Arctic and Antarctic sea ice. After a short review of these published factors, new observations and atmospheric, oceanic, hydrological, and geological mechanisms contributed to different behaviors of sea ice changes in the Arctic and Antarctic are presented. The contribution from of hydrologic factors may provide a linkage to and enhance thermal impacts from lower latitudes. While geological factors may affect the sensitivity of sea ice response to climate change, these factors can serve as the long-term memory in the system that should be exploited to improve future projections or predictions of sea ice changes. Furthermore, similarities and differences in chemical impacts of Arctic and Antarctic sea ice changes are discussed. Understanding sea ice changes and

Estimation of Melt Pond Fractions on First Year Sea Ice Using Compact Polarization SAR

Science.gov (United States)

Li, Haiyan; Perrie, William; Li, Qun; Hou, Yijun

2017-10-01

Melt ponds are a common feature on Arctic sea ice. They are linked to the sea ice surface albedo and transmittance of energy to the ocean from the atmosphere and thus constitute an important process to parameterize in Arctic climate models and simulations. This paper presents a first attempt to retrieve the melt pond fraction from hybrid-polarized compact polarization (CP) SAR imagery, which has wider swath and shorter revisit time than the quad-polarization systems, e.g., from RADARSAT-2 (RS-2). The co-polarization (co-pol) ratio has been verified to provide estimates of melt pond fractions. However, it is a challenge to link CP parameters and the co-pol ratio. The theoretical possibility is presented, for making this linkage with the CP parameter C22/C11 (the ratio between the elements of the coherence matrix of CP SAR) for melt pond detection and monitoring with the tilted-Bragg scattering model for the ocean surface. The empirical transformed formulation, denoted as the "compact polarization and quad-pol" ("CPQP") model, is proposed, based on 2062 RS-2 quad-pol SAR images, collocated with in situ measurements. We compared the retrieved melt pond fraction with CP parameters simulated from quad-pol SAR data with results retrieved from the co-pol ratio from quad-pol SAR observations acquired during the Arctic-Ice (Arctic-Ice Covered Ecosystem in a Rapidly Changing Environment) field project. The results are shown to be comparable for observed melt pond measurements in spatial and temporal distributions. Thus, the utility of CP mode SAR for melt pond fraction estimation on first year level ice is presented.

High resolution modelling of the decreasing Arctic sea ice

DEFF Research Database (Denmark)

Madsen, K. S.; Rasmussen, T. A. S.; Blüthgen, Jonas

2012-01-01

The Arctic sea ice cover has been rapidly decreasing and thinning over the last decade, with minimum ice extent in 2007 and almost as low extent in 2011. This study investigates two aspects of the decreasing ice cover; first the large scale thinning and changing dynamics of the polar sea ice, and...

Population genomics reveal recent speciation and rapid evolutionary adaptation in polar bears.

Science.gov (United States)

Liu, Shiping; Lorenzen, Eline D; Fumagalli, Matteo; Li, Bo; Harris, Kelley; Xiong, Zijun; Zhou, Long; Korneliussen, Thorfinn Sand; Somel, Mehmet; Babbitt, Courtney; Wray, Greg; Li, Jianwen; He, Weiming; Wang, Zhuo; Fu, Wenjing; Xiang, Xueyan; Morgan, Claire C; Doherty, Aoife; O'Connell, Mary J; McInerney, James O; Born, Erik W; Dalén, Love; Dietz, Rune; Orlando, Ludovic; Sonne, Christian; Zhang, Guojie; Nielsen, Rasmus; Willerslev, Eske; Wang, Jun

2014-05-08

Polar bears are uniquely adapted to life in the High Arctic and have undergone drastic physiological changes in response to Arctic climates and a hyper-lipid diet of primarily marine mammal prey. We analyzed 89 complete genomes of polar bear and brown bear using population genomic modeling and show that the species diverged only 479-343 thousand years BP. We find that genes on the polar bear lineage have been under stronger positive selection than in brown bears; nine of the top 16 genes under strong positive selection are associated with cardiomyopathy and vascular disease, implying important reorganization of the cardiovascular system. One of the genes showing the strongest evidence of selection, APOB, encodes the primary lipoprotein component of low-density lipoprotein (LDL); functional mutations in APOB may explain how polar bears are able to cope with life-long elevated LDL levels that are associated with high risk of heart disease in humans. Copyright © 2014 Elsevier Inc. All rights reserved.

Polish polar research (outline

Directory of Open Access Journals (Sweden)

Krzysztof Ludwik Birkenmajer

2017-12-01

Full Text Available The article describes Polish research and discoveries in the Arctic and the Antarctic since the 19th century. The author is a geologist and since 1956 has been engaged in scientific field research on Spitsbergen, Greenland and Antarctica (23 expeditions. For many years chairman of the Committee on Polar Research of the Polish Academy of Sciences, he is now its Honorary Chairman.

Polar bears, Ursus maritimus

Science.gov (United States)

Rode, Karyn D.; Stirling, Ian

2017-01-01

Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They range throughout the circumpolar Arctic to the southernmost extent of seasonal pack ice.

Effect of Recent Sea Surface Temperature Trends on the Arctic Stratospheric Vortex

Science.gov (United States)

Garfinkel, Chaim I.; Oman, Luke; Hurwitz, Margaret

2015-01-01

The springtime Arctic polar vortex has cooled significantly over the satellite era, with consequences for ozone concentrations in the springtime transition season. The causes of this cooling trend are deduced by using comprehensive chemistry-climate model experiments. Approximately half of the satellite era early springtime cooling trend in the Arctic lower stratosphere was caused by changing sea surface temperatures (SSTs). An ensemble of experiments forced only by changing SSTs is compared to an ensemble of experiments in which both the observed SSTs and chemically- and radiatively-active trace species are changing. By comparing the two ensembles, it is shown that warming of Indian Ocean, North Pacific, and North Atlantic SSTs, and cooling of the tropical Pacific, have strongly contributed to recent polar stratospheric cooling in late winter and early spring, and to a weak polar stratospheric warming in early winter. When concentrations of ozone-depleting substances and greenhouse gases are fixed, polar ozone concentrations show a small but robust decline due to changing SSTs. Ozone changes are magnified in the presence of changing gas concentrations. The stratospheric changes can be understood by examining the tropospheric height and heat flux anomalies generated by the anomalous SSTs. Finally, recent SST changes have contributed to a decrease in the frequency of late winter stratospheric sudden warmings.

Arctic-COLORS (Coastal Land Ocean Interactions in the Arctic) - a NASA field campaign scoping study to examine land-ocean interactions in the Arctic

Science.gov (United States)

Hernes, P.; Tzortziou, M.; Salisbury, J.; Mannino, A.; Matrai, P.; Friedrichs, M. A.; Del Castillo, C. E.

2014-12-01

The Arctic region is warming faster than anywhere else on the planet, triggering rapid social and economic changes and impacting both terrestrial and marine ecosystems. Yet our understanding of critical processes and interactions along the Arctic land-ocean interface is limited. Arctic-COLORS is a Field Campaign Scoping Study funded by NASA's Ocean Biology and Biogeochemistry Program that aims to improve understanding and prediction of land-ocean interactions in a rapidly changing Arctic coastal zone, and assess vulnerability, response, feedbacks and resilience of coastal ecosystems, communities and natural resources to current and future pressures. Specific science objectives include: - Quantify lateral fluxes to the arctic inner shelf from (i) rivers and (ii) the outer shelf/basin that affect biology, biodiversity, biogeochemistry (i.e. organic matter, nutrients, suspended sediment), and the processing rates of these constituents in coastal waters. - Evaluate the impact of the thawing of Arctic permafrost within the river basins on coastal biology, biodiversity and biogeochemistry, including various rates of community production and the role these may play in the health of regional economies. - Assess the impact of changing Arctic landfast ice and coastal sea ice dynamics. - Establish a baseline for comparison to future change, and use state-of-the-art models to assess impacts of environmental change on coastal biology, biodiversity and biogeochemistry. A key component of Arctic-COLORS will be the integration of satellite and field observations with coupled physical-biogeochemical models for predicting impacts of future pressures on Arctic, coastal ocean, biological processes and biogeochemical cycles. Through interagency and international collaborations, and through the organization of dedicated workshops, town hall meetings and presentations at international conferences, the scoping study engages the broader scientific community and invites participation of

Modeling the summertime Arctic cloudy boundary layer

Energy Technology Data Exchange (ETDEWEB)

Curry, J.A.; Pinto, J.O. [Univ. of Colorado, Boulder, CO (United States); McInnes, K.L. [CSIRO Division of Atmospheric Research, Mordialloc (Australia)

1996-04-01

Global climate models have particular difficulty in simulating the low-level clouds during the Arctic summer. Model problems are exacerbated in the polar regions by the complicated vertical structure of the Arctic boundary layer. The presence of multiple cloud layers, a humidity inversion above cloud top, and vertical fluxes in the cloud that are decoupled from the surface fluxes, identified in Curry et al. (1988), suggest that models containing sophisticated physical parameterizations would be required to accurately model this region. Accurate modeling of the vertical structure of multiple cloud layers in climate models is important for determination of the surface radiative fluxes. This study focuses on the problem of modeling the layered structure of the Arctic summertime boundary-layer clouds and in particular, the representation of the more complex boundary layer type consisting of a stable foggy surface layer surmounted by a cloud-topped mixed layer. A hierarchical modeling/diagnosis approach is used. A case study from the summertime Arctic Stratus Experiment is examined. A high-resolution, one-dimensional model of turbulence and radiation is tested against the observations and is then used in sensitivity studies to infer the optimal conditions for maintaining two separate layers in the Arctic summertime boundary layer. A three-dimensional mesoscale atmospheric model is then used to simulate the interaction of this cloud deck with the large-scale atmospheric dynamics. An assessment of the improvements needed to the parameterizations of the boundary layer, cloud microphysics, and radiation in the 3-D model is made.

Toward Process-resolving Synthesis and Prediction of Arctic Climate Change Using the Regional Arctic System Model

Science.gov (United States)

Maslowski, W.

2017-12-01

The Regional Arctic System Model (RASM) has been developed to better understand the operation of Arctic System at process scale and to improve prediction of its change at a spectrum of time scales. RASM is a pan-Arctic, fully coupled ice-ocean-atmosphere-land model with marine biogeochemistry extension to the ocean and sea ice models. The main goal of our research is to advance a system-level understanding of critical processes and feedbacks in the Arctic and their links with the Earth System. The secondary, an equally important objective, is to identify model needs for new or additional observations to better understand such processes and to help constrain models. Finally, RASM has been used to produce sea ice forecasts for September 2016 and 2017, in contribution to the Sea Ice Outlook of the Sea Ice Prediction Network. Future RASM forecasts, are likely to include increased resolution for model components and ecosystem predictions. Such research is in direct support of the US environmental assessment and prediction needs, including those of the U.S. Navy, Department of Defense, and the recent IARPC Arctic Research Plan 2017-2021. In addition to an overview of RASM technical details, selected model results are presented from a hierarchy of climate models together with available observations in the region to better understand potential oceanic contributions to polar amplification. RASM simulations are analyzed to evaluate model skill in representing seasonal climatology as well as interannual and multi-decadal climate variability and predictions. Selected physical processes and resulting feedbacks are discussed to emphasize the need for fully coupled climate model simulations, high model resolution and sensitivity of simulated sea ice states to scale dependent model parameterizations controlling ice dynamics, thermodynamics and coupling with the atmosphere and ocean.

Physiologically-based pharmacokinetic modelling of immune, reproductive and carcinogenic effects from contaminant exposure in polar bears (Ursus maritimus) across the Arctic.

Science.gov (United States)

Dietz, Rune; Gustavson, Kim; Sonne, Christian; Desforges, Jean-Pierre; Rigét, Frank F; Pavlova, Viola; McKinney, Melissa A; Letcher, Robert J

2015-07-01

Polar bears (Ursus maritimus) consume large quantities of seal blubber and other high trophic marine mammals and consequently have some of the highest tissue concentrations of organohalogen contaminants (OHCs) among Arctic biota. In the present paper we carried out a risk quotient (RQ) evaluation on OHC-exposed polar bears harvested from 1999 to 2008 and from 11 circumpolar subpopulations spanning from Alaska to Svalbard in order to evaluate the risk of OHC-mediated reproductive effects (embryotoxicity, teratogenicity), immunotoxicity and carcinogenicity (genotoxicity). This RQ evaluation was based on the Critical Body Residue (CBR) concept and a Physiologically-Based Pharmacokinetic Modelling (PBPK) approach using OHC concentrations measured in polar bear adipose or liver tissue. The range of OHC concentrations within polar bear populations were as follows for adipose, sum polychlorinated biphenyls ∑PCBs (1797-10,537 ng/g lw), sum methylsulphone-PCB ∑MeSO2-PCBs (110-672 ng/g lw), sum chlordanes ∑CHLs (765-3477 ng/g lw), α-hexachlorocyclohexane α-HCH (8.5-91.3 ng/g lw), β-hexachlorocyclohexane β-HCH (65.5-542 ng/g lw), sum chlorbenzenes ∑ClBzs (145-304 ng/g lw), dichlorodiphenyltrichloroethane ∑DDTs (31.5-206 ng/g lw), dieldrin (69-249 ng/g lw), polybrominated diphenyl ethers ∑PBDEs (4.6-78.4 ng/g lw). For liver, the perfluorooctanesulfonic acid (PFOS) concentrations ranged from 231-2792 ng/g ww. The total additive RQ from all OHCs ranged from 4.3 in Alaska to 28.6 in East Greenland bears for effects on reproduction, immune health and carcinogenicity, highlighting the important result that the toxic effect threshold (i.e. RQ>1) was exceeded for all polar bear populations assessed. PCBs were the main contributors for all three effect categories, contributing from 70.6% to 94.3% of the total risk and a RQ between 3.8-22.5. ∑MeSO2-PCBs were the second highest effect contributor for reproductive and immunological effects (0.17polar bears. We therefore

The Arctic Marine Pulses Model: Linking Contiguous Domains in the Pacific Arctic Region

Science.gov (United States)

Moore, S. E.; Stabeno, P. J.

2016-02-01

The Pacific Arctic marine ecosystem extends from the northern Bering Sea, across the Chukchi and into the East Siberian and Beaufort seas. Food webs in this domain are short, a simplicity that belies the biophysical complexity underlying trophic linkages from primary production to humans. Existing biophysical models, such as pelagic-benthic coupling and advective processes, provide frameworks for connecting certain aspects of the marine food web, but do not offer a full accounting of events that occur seasonally across the Pacific Arctic. In the course of the Synthesis of Arctic Research (SOAR) project, a holistic Arctic Marine Pulses (AMP) model was developed that depicts seasonal biophysical `pulses' across a latitudinal gradient, and linking four previously-described contiguous domains, including the: (i) Pacific-Arctic domain = the focal region; (ii) seasonal ice zone domain; (iii) Pacific marginal domain; and (iv) riverine coastal domain. The AMP model provides a spatial-temporal framework to guide research on dynamic ecosystem processes during this period of rapid biophysical changes in the Pacific Arctic. Some of the processes included in the model, such as pelagic-benthic coupling in the Northern Bering and Chukchi seas, and advection and upwelling along the Beaufort shelf, are already the focus of sampling via the Distributed Biological Observatory (DBO) and other research programs. Other aspects such as biological processes associated with the seasonal ice zone and trophic responses to riverine outflow have received less attention. The AMP model could be enhanced by the application of visualization tools to provide a means to watch a season unfold in space and time. The capability to track sea ice dynamics and water masses and to move nutrients, prey and upper-trophic predators in space and time would provide a strong foundation for the development of predictive human-inclusive ecosystem models for the Pacific Arctic.

Dynamical response of the Arctic winter stratosphere to global warming

Science.gov (United States)

Karpechko, A.; Manzini, E.

2017-12-01

Climate models often simulate dynamical warming of the Arctic stratosphere as a response to global warming in association with a strengthening of the deep branch of the Brewer-Dobson circulation; however until now, no satisfactory mechanism for such a response has been suggested. Here we investigate the role of stationary planetary waves in the dynamical response of the Arctic winter stratosphere circulation to global warming by analysing simulations performed with atmosphere-only Coupled Model Intercomparison Project Phase 5 (CMIP5) models driven by prescribed sea surface temperatures (SSTs). We focus on December-February (DJF) because this is the period when the troposphere and stratosphere are strongly coupled. When forced by increased SSTs, all the models analysed here simulate Arctic stratosphere dynamical warming, mostly due to increased upward propagation of quasi-stationary wave number 1, as diagnosed by the meridional eddy heat flux. By analysing intermodel spread in the response we show that the stratospheric warming and increased wave flux to the stratosphere correlate with the strengthening of the zonal winds in subtropics and mid-latitudes near the tropopause- a robust response to global warming. These results support previous studies of future Arctic stratosphere changes and suggest a dynamical warming of the Arctic wintertime polar vortex as the most likely response to global warming.

Collection of Arctic Ocean Data from US Navy Submarines on the New SCICEX Program

Science.gov (United States)

Smethie, W. M.; Sambrotto, R.; Boyd, T.; Richter-Menge, J.; Corbett, J.

2011-12-01

The SCICEX submarine Arctic science program originated in the 1990s when six dedicated science cruises were conducted in the Arctic Ocean aboard US Navy Sturgeon class submarines. After the cold war era Sturgeon class submarines were retired, several Science Accommodation cruises, for which a few days for scientific measurements were added to planned submarine transits through the Arctic Ocean, were carried out when opportunities arose. Renewed interest in conducting further Science Accommodation cruises on a regular basis to better document and understand how the Arctic Ocean responds to climate change resulted in publication of a scientific plan in 2010 (http://www.arctic.gov/publications/scicex_plan.pdf). In the spring of 2011 testing of data collection and water sampling methods aboard newer Virginia and Seawolf class submarines on transit from a Navy ice camp in the Beaufort Sea, was conducted in order to develop protocols and evaluate techniques. Ice draft measurements were also taken in the vicinity of the ice camp and near the North Pole to evaluate new data collection systems. This evaluation will include a comparison of the ice draft data with a comprehensive set of in situ ice thickness measurements taken near the ice camp. Under-ice submarine-launched eXpendable Condutivity Temperature Depth (XCTD) probes were deployed from the USS Connecticut (SSN-22), a Seawolf class submarine, and the resulting profiles compared to CTD casts from the APLIS ice station and historical profiles. Water samples were collected through the hull for measurements of tritium, helium isotopes, oxygen isotopes, chlorofluorocarbons, sulfur hexafluoride, nutrients, dissolved organic carbon, bacterioplankton, phytoplankton and particulates levels. These samples were returned to Lamont-Doherty Earth Observatory and were in the process of being measured at the time this abstract was written. Measurements completed at this time indicate good samples can be collected for CFC-12

A new fractional derivative and its application to explanation of polar bear hairs

OpenAIRE

Ji-Huan He; Zheng-Biao Li; Qing-li Wang

2016-01-01

A new fractional derivative is defined through the variational iteration method, and its application in explaining the excellent thermal protection of polar bear hairs is elucidated. The fractal porosity of its inner structure makes a polar bear mathematically adapted for living in a harsh Arctic region.

Arctic polynya and glacier interactions

Science.gov (United States)

Edwards, Laura

2013-04-01

Major uncertainties surround future estimates of sea level rise attributable to mass loss from the polar ice sheets and ice caps. Understanding changes across the Arctic is vital as major potential contributors to sea level, the Greenland Ice Sheet and the ice caps and glaciers of the Canadian Arctic archipelago, have experienced dramatic changes in recent times. Most ice mass loss is currently focused at a relatively small number of glacier catchments where ice acceleration, thinning and calving occurs at ocean margins. Research suggests that these tidewater glaciers accelerate and iceberg calving rates increase when warming ocean currents increase melt on the underside of floating glacier ice and when adjacent sea ice is removed causing a reduction in 'buttressing' back stress. Thus localised changes in ocean temperatures and in sea ice (extent and thickness) adjacent to major glacial catchments can impact hugely on the dynamics of, and hence mass lost from, terrestrial ice sheets and ice caps. Polynyas are areas of open water within sea ice which remain unfrozen for much of the year. They vary significantly in size (~3 km2 to > ~50,000 km2 in the Arctic), recurrence rates and duration. Despite their relatively small size, polynyas play a vital role in the heat balance of the polar oceans and strongly impact regional oceanography. Where polynyas develop adjacent to tidewater glaciers their influence on ocean circulation and water temperatures may play a major part in controlling subsurface ice melt rates by impacting on the water masses reaching the calving front. Areas of open water also play a significant role in controlling the potential of the atmosphere to carry moisture, as well as allowing heat exchange between the atmosphere and ocean, and so can influence accumulation on (and hence thickness of) glaciers and ice caps. Polynya presence and size also has implications for sea ice extent and therefore potentially the buttressing effect on neighbouring

Rebuttal of "Polar bear population forecasts: a public-policy forecasting audit"

Science.gov (United States)

Steven C. Amstrup; Hal Caswell; Eric DeWeaver; Ian Stirling; David C. Douglas; Bruce G. Marcot; Christine M. Hunter

2009-01-01

Observed declines in the Arctic sea ice have resulted in a variety of negative effects on polar bears (Ursus maritimus). Projections for additional future declines in sea ice resulted in a proposal to list polar bears as a threatened species under the United States Endangered Species Act. To provide information for the Department of the Interior...

Seasonal patterns in Arctic prasinophytes and inferred ecology of Bathycoccus unveiled in an Arctic winter metagenome.

Science.gov (United States)

Joli, Nathalie; Monier, Adam; Logares, Ramiro; Lovejoy, Connie

2017-06-01

Prasinophytes occur in all oceans but rarely dominate phytoplankton populations. In contrast, a single ecotype of the prasinophyte Micromonas is frequently the most abundant photosynthetic taxon reported in the Arctic from summer through autumn. However, seasonal dynamics of prasinophytes outside of this period are little known. To address this, we analyzed high-throughput V4 18S rRNA amplicon data collected from November to July in the Amundsen Gulf Region, Beaufort Sea, Arctic. Surprisingly during polar sunset in November and December, we found a high proportion of reads from both DNA and RNA belonging to another prasinophyte, Bathycoccus. We then analyzed a metagenome from a December sample and the resulting Bathycoccus metagenome assembled genome (MAG) covered ~90% of the Bathycoccus Ban7 reference genome. In contrast, only ~20% of a reference Micromonas genome was found in the metagenome. Our phylogenetic analysis of marker genes placed the Arctic Bathycoccus in the B1 coastal clade. In addition, substitution rates of 129 coding DNA sequences were ~1.6% divergent between the Arctic MAG and coastal Chilean upwelling MAGs and 17.3% between it and a South East Atlantic open ocean MAG in the B2 Clade. The metagenomic analysis also revealed a winter viral community highly skewed toward viruses targeting Micromonas, with a much lower diversity of viruses targeting Bathycoccus. Overall a combination of Micromonas being relatively less able to maintain activity under dark winter conditions and viral suppression of Micromonas may have contributed to the success of Bathycoccus in the Amundsen Gulf during winter.

A new fractional derivative and its application to explanation of polar bear hairs

Directory of Open Access Journals (Sweden)

Ji-Huan He

2016-04-01

Full Text Available A new fractional derivative is defined through the variational iteration method, and its application in explaining the excellent thermal protection of polar bear hairs is elucidated. The fractal porosity of its inner structure makes a polar bear mathematically adapted for living in a harsh Arctic region.

Arctide2017, a high-resolution regional tidal model in the Arctic Ocean

DEFF Research Database (Denmark)

Cancet, M.; Andersen, O. B.; Lyard, F.

2018-01-01

The Arctic Ocean is a challenging region for tidal modelling. The accuracy of the global tidal models decreases by several centimeters in the Polar Regions, which has a large impact on the quality of the satellite altimeter sea surface heights and the altimetry-derived products. NOVELTIS, DTU Space...... and LEGOS have developed Arctide2017, a regional, high-resolution tidal atlas in the Arctic Ocean, in the framework of an extension of the CryoSat Plus for Ocean (CP4O) ESA STSE (Support to Science Element) project. In particular, this atlas benefits from the assimilation of the most complete satellite...... assimilation and validation. This paper presents the implementation methodology and the performance of this new regional tidal model in the Arctic Ocean, compared to the existing global and regional tidal models....

The Opening of the Arctic-Atlantic Gateway: Tectonic, Oceanographic and Climatic Dynamics - an IODP Initiative

Science.gov (United States)

Geissler, Wolfram; Knies, Jochen

2016-04-01

The modern polar cryosphere reflects an extreme climate state with profound temperature gradients towards high-latitudes. It developed in association with stepwise Cenozoic cooling, beginning with ephemeral glaciations and the appearance of sea ice in the late middle Eocene. The polar ocean gateways played a pivotal role in changing the polar and global climate, along with declining greenhouse gas levels. The opening of the Drake Passage finalized the oceanographic isolation of Antarctica, some 40 Ma ago. The Arctic Ocean was an isolated basin until the early Miocene when rifting and subsequent sea-floor spreading started between Greenland and Svalbard, initiating the opening of the Fram Strait / Arctic-Atlantic Gateway (AAG). Although this gateway is known to be important in Earth's past and modern climate, little is known about its Cenozoic development. However, the opening history and AAG's consecutive widening and deepening must have had a strong impact on circulation and water mass exchange between the Arctic Ocean and the North Atlantic. To study the AAG's complete history, ocean drilling at two primary sites and one alternate site located between 73°N and 78°N in the Boreas Basin and along the East Greenland continental margin are proposed. These sites will provide unprecedented sedimentary records that will unveil (1) the history of shallow-water exchange between the Arctic Ocean and the North Atlantic, and (2) the development of the AAG to a deep-water connection and its influence on the global climate system. The specific overarching goals of our proposal are to study: (1) the influence of distinct tectonic events in the development of the AAG and the formation of deep water passage on the North Atlantic and Arctic paleoceanography, and (2) the role of the AAG in the climate transition from the Paleogene greenhouse to the Neogene icehouse for the long-term (~50 Ma) climate history of the northern North Atlantic. Getting a continuous record of the

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

Hydrocarbons in the Arctic: Economic prospects and environmental issues

International Nuclear Information System (INIS)

Eschard, Remi; Vially, Roland; Benard, Francine

2011-01-01

Petroleum installations in the Arctic differ widely owing to the region's complex geological history. They are classical, but prospecting and producing from 'polar' fields represent a technological challenge given the extreme climatic conditions. The distance of oil and gas fields from zones of consumption and the transportation difficulties entail gigantic investments for working these fields and bringing their production to the marketplace

The Power of the Capability Constraint: On Russia’s Strength in the Arctic Territorial Dispute

Directory of Open Access Journals (Sweden)

Valko Irina

2016-04-01

Full Text Available Based on a geographical-administrative definition of the region, the theoretical assumptions of contemporary French structuralist geopolitics, cross-sectional data for 1990, 1995, 2000, 2005 and 2010 from the Updated Arctic Regional Attributes Dataset, and the technical capabilities of MS Office Excel 2010, this research (a reveals and contrasts the Arctic states’ capability constraints deriving from their longitudinal material and virtual power potential (physical potential, socio-economic potential, military potential, and symbolic potential; and (b analyses the role of this constraint in the process of preference formation in case of one specific Arctic actor, Russia, in the Arctic territorial dispute. This study confirms that Russia’s capability constraint is the lowest in the region and that the latter does not form a stable trend throughout the period studied. It also suggests the preference formation framework for Russia in the Arctic dispute based on the evolution of its polar capability constraint.

Polar politics : sovereignty tussles over Arctic territory threaten to impede oil and gas exploration

International Nuclear Information System (INIS)

Lorenz, A.W.

2007-01-01

Competition to secure oil and gas leases is concerning scientists who believe that the exploitation of mineral resources in the Arctic will damage the region faster than climate change. Scientists in the region have noted that hydrogen sulphide induced by sulphur-oxidizing bacteria are now thriving within glaciers in the Arctic. Imperial Oil and ExxonMobil Canada recently purchased 205,000 hectares in the Beaufort Sea, and the purchase is seen as a harbinger of further development in the region. Disputes between Canada and the United States are now beginning to cause controversy in the region. Climatic change may mean that the region will be ice-free in 50 years. Climatic change will also result in the destabilization of permafrost and in rises in sea levels. Melting of permafrost could cause subsidence and further difficulties for exploration engineers. If Canada is not able to convince the United Nations that the Northwest Passage constitutes internal waters, the environmental impacts of Russian resource development could be profound. In addition, offshore boundaries between the Yukon and Alaska are interpreted differently by Canadians and Americans. It was suggested that discussions are needed to ensure Canada's role in the Arctic. 2 figs

Molecular identification of Trichinella isolates from wildlife animals of the Russian Arctic territories

Directory of Open Access Journals (Sweden)

Goździk K.

2017-03-01

Full Text Available The parasitic nematodes of genus Trichinella are infective to a wide range of hosts, including humans, and have global distribution from tropic to arctic areas. Muscle samples from animals, collected in two areas of the Russian Federation, Chukotka Peninsula and Arkhangelsk Oblast, were tested for the presence of Trichinella spp. larvae. Trichinella spp. larvae were recovered from tissues of eleven wild and domestic animals: 1 polar bear, 1 wolverine, 3 arctic foxes, 1 ringed seal, 1 brown bear, 1 cat, 1 sled dog, 1 domestic pig and 1 northern sea lion.

Environmental impact on the polar regions

International Nuclear Information System (INIS)

Jaffe, D.A.; Leighton, E.; Tumeo, M.A.

1994-01-01

The remote and frigid polar regions are no longer isolated from the activities, pollutants, and controversies that bedevil their more temperate neighbors, say three researchers at the University of Alaska in Fairbanks. For example, Daniel A. Jaffe, Elizabeth Leighton, and Mark A. Tumeo point to traces of DDT, PCBs, and heavy metals that routinely turn up in arctic marine mammals and to the ozone hole over the Antarctic. While similar in environmental makeup, the arctic and Antarctic are poles apart in their political structure and, thus, in their environmental exposure, the researchers note. The Antarctic is managed under a long-standing international treaty, while the arctic is sovereign territory to eight separate nations. The international treaty sets aside the Antarctic for peaceful scientific research within strict environmental boundaries. It bans both military activity and minerals extraction-the two activities that have caused the most damage in the arctic. The main threats to Antarctica's environment come from the intrusion of major scientific research operations and the growing tourism industry. On the other hand, the arctic suffered from the massive Cold War military buildup by both the United States and the former Soviet Union. The environmental residue from that buildup is only now being revealed, the authors say. Major oil and gas drilling and coal and metal-ore mining also have taken a huge environmental toll, they add

A Recommended Set of Key Arctic Indicators

Science.gov (United States)

Stanitski, D.; Druckenmiller, M.; Fetterer, F. M.; Gerst, M.; Intrieri, J. M.; Kenney, M. A.; Meier, W.; Overland, J. E.; Stroeve, J.; Trainor, S.

2017-12-01

The Arctic is an interconnected and environmentally sensitive system of ice, ocean, land, atmosphere, ecosystems, and people. From local to pan-Arctic scales, the area has already undergone major changes in physical and societal systems and will continue at a pace that is greater than twice the global average. Key Arctic indicators can quantify these changes. Indicators serve as the bridge between complex information and policy makers, stakeholders, and the general public, revealing trends and information people need to make important socioeconomic decisions. This presentation evaluates and compiles more than 70 physical, biological, societal and economic indicators into an approachable summary that defines the changing Arctic. We divided indicators into "existing," "in development," "possible," and "aspirational". In preparing a paper on Arctic Indicators for a special issue of the journal Climatic Change, our group established a set of selection criteria to identify indicators to specifically guide decision-makers in their responses to climate change. A goal of the analysis is to select a manageable composite list of recommended indicators based on sustained, reliable data sources with known user communities. The selected list is also based on the development of a conceptual model that identifies components and processes critical to our understanding of the Arctic region. This list of key indicators is designed to inform the plans and priorities of multiple groups such as the U.S. Global Change Research Program (USGCRP), Interagency Arctic Research Policy Committee (IARPC), and the Arctic Council.

Late Pleistocene and Holocene meltwater events in the western Arctic Ocean

Science.gov (United States)

Poore, R.Z.; Osterman, L.; Curry, W.B.; Phillips, R.L.

1999-01-01

Accelerator mass spectrometer 14C dated stable isotope data from Neogloboquadrina pachyerma in cores raised from the Mendeleyev Ridge and slope provide evidence for significant influx of meltwater to the western Arctic Ocean during the early part of marine oxygen isotope stage 1 (OIS 1) and during several intervals within OIS 3. The strongest OIS 3 meltwater event occurred before ca. 45 ka (conventional radiocarbon age) and was probably related to the deglaciation at the beginning of OIS 3. Major meltwater input to the western Arctic Ocean during the last deglaciation coincides closely with the maximum rate of global sea-level rise as determined from the Barbados sea-level record, demonstrating a strong link between the global record and changes in the central Arctic Ocean. OIS 2, which includes the last glacial maximum, is very condensed or absent in the cores. Abundance and ??13C values for N. pachyderma in the middle part of OIS 3 are similar to modern values, indicating high productivity and seasonal ice-free areas along the Arctic margin at that time. These records indicate that the Arctic Ocean was a source of heat and moisture to the northern polar atmosphere during parts of OIS 3.

A dynamical link between the Arctic and the global climate system

DEFF Research Database (Denmark)

Dethloff, K.; Rinke, A.; Benkel, A.

2006-01-01

and snow albedo treatment changes the ice-albedo feedback and the radiative exchange between the atmosphere and the ocean-sea-ice system. The planetary wave energy fluxes in the middle troposphere of mid-latitudes between 30 and 50°N are redistributed, which induces perturbations in the zonal...... and meridional planetary wave trains from the tropics over the mid-latitudes into the Arctic. It is shown, that the improved parameterization of Arctic sea-ice and snow albedo can trigger changes in the Arctic and North Atlantic Oscillation pattern with strong implications for the European climate.......By means of simulations with a global coupled AOGCM it is shown that changes in the polar energy sink region can exert a strong influence on the mid- and high-latitude climate by modulating the strength of the mid-latitude westerlies and storm tracks. It is found, that a more realistic sea-ice...

Ship emissions measurement in the Arctic by plume intercepts of the Canadian Coast Guard icebreaker Amundsen from the Polar 6 aircraft platform

Science.gov (United States)

Aliabadi, Amir A.; Thomas, Jennie L.; Herber, Andreas B.; Staebler, Ralf M.; Leaitch, W. Richard; Schulz, Hannes; Law, Kathy S.; Marelle, Louis; Burkart, Julia; Willis, Megan D.; Bozem, Heiko; Hoor, Peter M.; Köllner, Franziska; Schneider, Johannes; Levasseur, Maurice; Abbatt, Jonathan P. D.

2016-06-01

Decreasing sea ice and increasing marine navigability in northern latitudes have changed Arctic ship traffic patterns in recent years and are predicted to increase annual ship traffic in the Arctic in the future. Development of effective regulations to manage environmental impacts of shipping requires an understanding of ship emissions and atmospheric processing in the Arctic environment. As part of the summer 2014 NETCARE (Network on Climate and Aerosols) campaign, the plume dispersion and gas and particle emission factors of effluents originating from the Canadian Coast Guard icebreaker Amundsen operating near Resolute Bay, NU, Canada, were investigated. The Amundsen burned distillate fuel with 1.5 wt % sulfur. Emissions were studied via plume intercepts using the Polar 6 aircraft measurements, an analytical plume dispersion model, and using the FLEXPART-WRF Lagrangian particle dispersion model. The first plume intercept by the research aircraft was carried out on 19 July 2014 during the operation of the Amundsen in the open water. The second and third plume intercepts were carried out on 20 and 21 July 2014 when the Amundsen had reached the ice edge and operated under ice-breaking conditions. Typical of Arctic marine navigation, the engine load was low compared to cruising conditions for all of the plume intercepts. The measured species included mixing ratios of CO2, NOx, CO, SO2, particle number concentration (CN), refractory black carbon (rBC), and cloud condensation nuclei (CCN). The results were compared to similar experimental studies in mid-latitudes. Plume expansion rates (γ) were calculated using the analytical model and found to be γ = 0.75 ± 0.81, 0.93 ± 0.37, and 1.19 ± 0.39 for plumes 1, 2, and 3, respectively. These rates were smaller than prior studies conducted at mid-latitudes, likely due to polar boundary layer dynamics, including reduced turbulent mixing compared to mid-latitudes. All emission factors were in agreement with prior

Performance and microbial community structure of a polar Arctic Circle aerobic granular sludge system operating at low temperature.

Science.gov (United States)

Gonzalez-Martinez, Alejandro; Muñoz-Palazon, Barbara; Maza-Márquez, Paula; Rodriguez-Sanchez, Alejandro; Gonzalez-Lopez, Jesus; Vahala, Riku

2018-05-01

The aim of this work was to study the performance and microbial community structure of a polar Arctic Circle aerobic granular sludge (AGS) system operating at low temperature. Thus, an AGS bioreactor was operated at 7, 5 and 3 °C of temperature using a cold-adapted sludge from Lapland. At 5 °C, it yielded acceptable conversion rates, in terms of nitrogen, phosphorous, and organic matter. However, under 3 °C a negligible nitrogen and phosphorous removal performance was observed. Below 5 °C, scanning electron microscopy studies showed a wispy, non-dense and irregular granular structure with a strong outgrowth of filamentous. Moreover, Illumina next-generation sequencing showed a heterogeneous microbial population where SM1K20 (Archaea), Trichosporon domesticum (Fungus), and Zooglea, Arcobacter and Acinetobacter (Bacteria) were the dominant phylotypes. Our study suggests that AGS technologies inoculated with North Pole sludge could be operated, in cold regions for a period longer than 3 months (winter season) under 5 °C of water temperature. Copyright © 2018 Elsevier Ltd. All rights reserved.

Climate Change: Science and Policy in the Arctic Climate Change: Science and Policy in the Arctic

Science.gov (United States)

Bigras, S. C.

2009-12-01

participation of indigenous peoples in the development and management process. The effective application of accumulated climate change knowledge requires development of a policy framework that can address cumulative effects and take into account various stakeholders, multi-jurisdictional regulations and interests, environmental impacts and other concerns specific to the Arctic. Fundamental to such a framework are responsible economic development, sustainable communities, the commitment to achieving consensus between parties, and the use of traditional knowledge. One way to facilitate collaborative policy making is to increase international co-operation between Northerners, indigenous peoples, scientists, politicians and policy makers. The International Polar Year (IPY) 2007-2008 proved a solid stepping-stone for multinational collaborations. Clear communication with politicians and policy-makers is challenging but essential, despite the lingering uncertainties in climate-change science. Public awareness helps considerably in getting messages to politicians, and it is therefore important that scientists and researchers share their results not only with colleagues but also with the general public.

Morbillivirus and Toxoplasma exposure and association with hematological parameters for southern Beaufort Sea polar bears: potential response to infectious agents in a sentinel species

Science.gov (United States)

Kirk, Cassandra M.; Amstrup, Steven C.; Swor, Rhonda; Holcomb, Darce; O'Hara, Todd M.

2010-01-01

Arctic temperatures are increasing in response to greenhouse gas forcing and polar bears have already responded to changing conditions. Declines in body stature and vital rates have been linked to warming-induced loss of sea-ice. As food webs change and human activities respond to a milder Arctic, exposure of polar bears and other arctic marine organisms to infectious agents may increase. Because of the polar bear’s status as arctic ecosystem sentinel, polar bear health could provide an index of changing pathogen occurrence throughout the Arctic, however, exposure and monitoring protocols have yet to be established. We examine prevalence of antibodies to Toxoplasma gondii, and four morbilliviruses (canine distemper [CDV], phocine distemper [PDV], dolphin morbillivirus [DMV], porpoise morbillivirus [PMV]) including risk factors for exposure. We also examine the relationships between antibody levels and hematologic values established in the previous companion article. Antibodies to Toxoplasma gondii and morbilliviruses were found in both sample years. We found a significant inverse relationship between CDV titer and total leukocytes, neutrophils, monocytes, and eosinophils, and a significant positive relationship between eosinophils and Toxoplasma gondii antibodies. Morbilliviral prevalence varied significantly among age cohorts, with 1–2 year olds least likely to be seropositive and bears aged 5–7 most likely. Data suggest that the presence of CDV and Toxoplasma gondii antibodies is associated with polar bear hematologic values. We conclude that exposure to CDV-like antigen is not randomly distributed among age classes and suggest that differing behaviors among life history stages may drive probability of specific antibody presence.

Morbillivirus and Toxoplasma exposure and association with hematological parameters for southern Beaufort Sea polar bears: potential response to infectious agents in a sentinel species.

Science.gov (United States)

Kirk, Cassandra M; Amstrup, Steven; Swor, Rhonda; Holcomb, Darce; O'Hara, Todd M

2010-09-01

Arctic temperatures are increasing in response to greenhouse gas forcing and polar bears have already responded to changing conditions. Declines in body stature and vital rates have been linked to warming-induced loss of sea-ice. As food webs change and human activities respond to a milder Arctic, exposure of polar bears and other arctic marine organisms to infectious agents may increase. Because of the polar bear's status as arctic ecosystem sentinel, polar bear health could provide an index of changing pathogen occurrence throughout the Arctic, however, exposure and monitoring protocols have yet to be established. We examine prevalence of antibodies to Toxoplasma gondii, and four morbilliviruses (canine distemper [CDV], phocine distemper [PDV], dolphin morbillivirus [DMV], porpoise morbillivirus [PMV]) including risk factors for exposure. We also examine the relationships between antibody levels and hematologic values established in the previous companion article. Antibodies to Toxoplasma gondii and morbilliviruses were found in both sample years. We found a significant inverse relationship between CDV titer and total leukocytes, neutrophils, monocytes, and eosinophils, and a significant positive relationship between eosinophils and Toxoplasma gondii antibodies. Morbilliviral prevalence varied significantly among age cohorts, with 1-2 year olds least likely to be seropositive and bears aged 5-7 most likely. Data suggest that the presence of CDV and Toxoplasma gondii antibodies is associated with polar bear hematologic values. We conclude that exposure to CDV-like antigen is not randomly distributed among age classes and suggest that differing behaviors among life history stages may drive probability of specific antibody presence.

Cases of Lightweight Structures for Polar Areas

DEFF Research Database (Denmark)

Pedreros, Jessica Fernandoy; Christ, Julian; Shepherd, Paul

2017-01-01

The paper focuses on what the authors call ‘Polar Lightweight Structures’. The first part presents a collection of lightweight structures (LWS) designed and built for Antarctic conditions, with the aim of demonstrating the diversity of approaches attempted by designers. The second part of the paper...... presents two studies where different computational methods were applied for the design of generic LWS based on the local conditions of two particular Polar locations; namely, the Arctic region and Glacier Union in the Antarctic plateau. Both studies were conducted independently with the aim...

Breaking the Ice: Strategies for Future European Research in the Polar Oceans - The AURORA BOREALIS Concept

Science.gov (United States)

Lembke-Jene, L.; Biebow, N.; Wolff-Boenisch, B.; Thiede, J.; European Research Icebreaker Consortium

2011-12-01

Research vessels dedicated to work in polar ice-covered waters have only rarely been built. Their history began with Fritjof Nansen's FRAM, which he used for his famous first crossing of the Arctic Ocean 1893-1896. She served as example for the first generation of polar research vessels, at their time being modern instruments planned with foresight. Ice breaker technology has developed substantially since then. However, it took almost 80 years until this technical advance also reached polar research, when the Russian AKADEMIK FEDEROV, the German POLARSTERN, the Swedish ODEN and the USCG Cutter HEALY were built. All of these house modern laboratories, are ice-breakers capable to move into the deep-Arctic during the summer time and represent the second generation of dedicated polar research vessels. Still, the increasing demand in polar marine research capacities by societies that call for action to better understand climate change, especially in the high latitudes is not matched by adequate facilities and resources. Today, no icebreaker platform exists that is permanently available to the international science community for year-round expeditions into the central Arctic Ocean or heavily ice-infested waters of the polar Southern Ocean around Antarctica. The AURORA BOREALIS concept plans for a heavy research icebreaker, which will enable polar scientists around the world to launch international research expeditions into the central Arctic Ocean and the Antarctic continental shelf seas autonomously during all seasons of the year. The European Research Icebreaker Consortium - AURORA BOREALIS (ERICON-AB) was established in 2008 to plan the scientific, governance, financial, and legal frameworks needed for the construction and operation of this first multi-nationally owned and operated research icebreaker and polar scientific drilling platform. By collaborating together and sharing common infrastructures it is envisioned that European nations make a major contribution to

INTERNATIONAL EXPERIENCE AND TRENDS OF INNOVATIVE DEVELOPMENT OF ARCTIC TERRITORIES

Directory of Open Access Journals (Sweden)

M. Dudin

2015-01-01

Full Text Available In this article and summarized the regularities of formation of foreign experience and trends of development of Arctic territories. Set out the important points predetermine orientation and specificity of manifestations of national interests – potential participants of the subsoil in the Arctic zone. On the basis of the illuminated materials were obtained the following conclusions: Signifi cant interest in the Arctic show today, not only the fi ve countries (Russia, USA, Canada, Norway, Denmark, who own Arctic territories, but also polar state (Iceland, Sweden, Finland, the European Union and Asia. As a consequence of that, it is expected that in the XXI century the Arctic region will be the focus of attention as an official Arctic 45, and a number of states whose territory is quite removed from it; For Russia, given the current, acute political conditions (sanctions, confrontation with the West, Ukrainian crisis and war in the Middle East development of Arctic territories, some moved away, moved on tomorrow and the day after tomorrow on the agenda. This approach is fundamentally fl awed and fraught with a number of threats, because other countries do not decrease, but only increase their interest in this issue; Territorial opposition to all those involved in the topic of causing instability in the Arctic region, but does not represent a real threat for the emergence of large-scale conflict. Therefore, making the choice between the hard pressure of national interests and the interests of harmonization of the Arctic states, Russia must be based on international cooperationand mutual consideration of interests in the development of its Arctic strategy; Considering the cooperation of the countries of the Arctic Council and their cooperation in the framework of a global economic forum G8, there are prerequisites for the decision of the Arctic confl ict through negotiation and compromise. In this context it is very important to develop

Trichinella in arctic, subarctic and temperate regions

DEFF Research Database (Denmark)

Kapel, C. M O

1997-01-01

The transmission and occurrence of Trichinella spp according to the zoogeography of different climatic conditions, socioeconomy and human activity are discussed. Comparing arctic, subarctic and temperate regions, it appears that the species of Trichinella present, the composition of the fauna...... and the human activity are all very important interacting factors affecting epidemiology. In Greenland, where only sylvatic trichinellosis is present, the high prevalence in wildlife appears closely connected with polar bear hunting. In the Scandinavian countries, the prevalence of both sylvatic and domestic...

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: M_MAMMAL (Marine Mammal Polygons)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, whales, walruses, polar bears, and Steller sea lions in Northwest Arctic, Alaska. Vector...

Mercury bioaccumulation and biomagnification in a small Arctic polynya ecosystem

Energy Technology Data Exchange (ETDEWEB)

Clayden, Meredith G., E-mail: meredith.clayden@gmail.com [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); Arsenault, Lilianne M. [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); Department of Earth and Environmental Science, Acadia University, Wolfville, NS B4P 2R6 (Canada); Department of Biology, Acadia University, Wolfville, NS B4P 2R6 (Canada); Kidd, Karen A. [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); O' Driscoll, Nelson J. [Department of Earth and Environmental Science, Acadia University, Wolfville, NS B4P 2R6 (Canada); Mallory, Mark L. [Department of Biology, Acadia University, Wolfville, NS B4P 2R6 (Canada)

2015-03-15

Recurring polynyas are important areas of biological productivity and feeding grounds for seabirds and mammals in the Arctic marine environment. In this study, we examined food web structure (using carbon and nitrogen isotopes, δ{sup 13}C and δ{sup 15}N) and mercury (Hg) bioaccumulation and biomagnification in a small recurring polynya ecosystem near Nasaruvaalik Island (Nunavut, Canada). Methyl Hg (MeHg) concentrations increased by more than 50-fold from copepods (Calanus hyperboreus) to Arctic terns (Sterna paradisaea), the abundant predators at this site. The biomagnification of MeHg through members of the food web – using the slope of log MeHg versus δ{sup 15}N – was 0.157 from copepods (C. hyperboreus) to fish. This slope was higher (0.267) when seabird chicks were included in the analyses. Collectively, our results indicate that MeHg biomagnification is occurring in this small polynya and that its trophic transfer is at the lower end of the range of estimates from other Arctic marine ecosystems. In addition, we measured Hg concentrations in some poorly studied members of Arctic marine food webs [e.g. Arctic alligatorfish (Ulcina olrikii) and jellyfish, Medusozoa], and found that MeHg concentrations in jellyfish were lower than expected given their trophic position. Overall, these findings provide fundamental information about food web structure and mercury contamination in a small Arctic polynya, which will inform future research in such ecosystems and provide a baseline against which to assess changes over time resulting from environmental disturbance. - Highlights: • Polynyas are recurring sites of open water in polar marine areas • Mercury (Hg) biomagnification was studied in a small polynya near Nasaruvaalik Island, NU, Canada • Hg biomagnification estimates for invertebrates to fish were low compared to other Arctic systems • Factors underlying this result are unknown but may relate to primary productivity in small polynyas.

Mercury bioaccumulation and biomagnification in a small Arctic polynya ecosystem

International Nuclear Information System (INIS)

Clayden, Meredith G.; Arsenault, Lilianne M.; Kidd, Karen A.; O'Driscoll, Nelson J.; Mallory, Mark L.

2015-01-01

Recurring polynyas are important areas of biological productivity and feeding grounds for seabirds and mammals in the Arctic marine environment. In this study, we examined food web structure (using carbon and nitrogen isotopes, δ 13 C and δ 15 N) and mercury (Hg) bioaccumulation and biomagnification in a small recurring polynya ecosystem near Nasaruvaalik Island (Nunavut, Canada). Methyl Hg (MeHg) concentrations increased by more than 50-fold from copepods (Calanus hyperboreus) to Arctic terns (Sterna paradisaea), the abundant predators at this site. The biomagnification of MeHg through members of the food web – using the slope of log MeHg versus δ 15 N – was 0.157 from copepods (C. hyperboreus) to fish. This slope was higher (0.267) when seabird chicks were included in the analyses. Collectively, our results indicate that MeHg biomagnification is occurring in this small polynya and that its trophic transfer is at the lower end of the range of estimates from other Arctic marine ecosystems. In addition, we measured Hg concentrations in some poorly studied members of Arctic marine food webs [e.g. Arctic alligatorfish (Ulcina olrikii) and jellyfish, Medusozoa], and found that MeHg concentrations in jellyfish were lower than expected given their trophic position. Overall, these findings provide fundamental information about food web structure and mercury contamination in a small Arctic polynya, which will inform future research in such ecosystems and provide a baseline against which to assess changes over time resulting from environmental disturbance. - Highlights: • Polynyas are recurring sites of open water in polar marine areas • Mercury (Hg) biomagnification was studied in a small polynya near Nasaruvaalik Island, NU, Canada • Hg biomagnification estimates for invertebrates to fish were low compared to other Arctic systems • Factors underlying this result are unknown but may relate to primary productivity in small polynyas

CryoSat-2 altimetry derived Arctic bathymetry map: first results and validation

Science.gov (United States)

Andersen, O. B.; Abulaitijiang, A.; Cancet, M.; Knudsen, P.

2017-12-01

The Technical University of Denmark (DTU), DTU Space has been developing high quality high resolution gravity fields including the new highly accurate CryoSat-2 radar altimetry satellite data which extends the global coverage of altimetry data up to latitude 88°. With its exceptional Synthetic Aperture Radar (SAR) mode being operating throughout the Arctic Ocean, leads, i.e., the ocean surface heights, is used to retrieve the sea surface height with centimeter-level range precision. Combined with the long repeat cycle ( 369 days), i.e., dense cross-track coverage, the high-resolution Arctic marine gravity can be modelled using the CryoSat-2 altimetry. Further, the polar gap can be filled by the available ArcGP product, thus yielding the complete map of the Arctic bathymetry map. In this presentation, we will make use of the most recent DTU17 marine gravity, to derive the arctic bathymetry map using inversion based on best available hydrographic maps. Through the support of ESA a recent evaluation of existing hydrographic models of the Arctic Ocean Bathymetry models (RTOPO, GEBCO, IBCAO etc) and various inconsistencies have been identified and means to rectify these inconsistencies have been taken prior to perform the inversion using altimetry. Simultaneously DTU Space has been placing great effort on the Arctic data screening, filtering, and de-noising using various altimetry retracking solutions and classifications. All the pre-processing contributed to the fine modelling of Actic gravity map. Thereafter, the arctic marine gravity grids will eventually be translated (downward continuation operation) to a new altimetry enhanced Arctic bathymetry map using appropriate band-pass filtering.

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.

Engaging Students in Science Courses: Lessons of Change from the Arctic

Science.gov (United States)

Duffy, Lawrence K.; Godduhn, Anna; Fabbri, Cindy E.; van Muelken, Mary; Nicholas-Figueroa, Linda; Middlecamp, Catherine Hurt

2011-01-01

Where you live should have something to do with what you teach. In the Arctic, the idea of place-based education--teaching and sharing knowledge that is needed to live well--is central to the UARCTIC consortium and the 4th International Polar Year educational reform effort. A place-based issue oriented context can engage students in chemistry…

Phylogeography of mitochondrial DNA variation in brown bears and polar bears.

Science.gov (United States)

Shields, G F; Adams, D; Garner, G; Labelle, M; Pietsch, J; Ramsay, M; Schwartz, C; Titus, K; Williamson, S

2000-05-01

We analyzed 286 nucleotides of the middle portion of the mitochondrial cytochrome b gene of 61 brown bears from three locations in Alaska and 55 polar bears from Arctic Canada and Arctic Siberia to test our earlier observations of paraphyly between polar bears and brown bears as well as to test the extreme uniqueness of mitochondrial DNA types of brown bears on Admiralty, Baranof, and Chichagof (ABC) islands of southeastern Alaska. We also investigated the phylogeography of brown bears of Alaska's Kenai Peninsula in relation to other Alaskan brown bears because the former are being threatened by increased human development. We predicted that: (1) mtDNA paraphyly between brown bears and polar bears would be upheld, (2) the mtDNA uniqueness of brown bears of the ABC islands would be upheld, and (3) brown bears of the Kenai Peninsula would belong to either clade II or clade III of brown bears of our earlier studies of mtDNA. All of our predictions were upheld through the analysis of these additional samples. Copyright 2000 Academic Press.

Phylogeography of mitochondrial DNA variation in brown bears and polar bears

Science.gov (United States)

Shields, Gerald F.; Adams, Deborah; Garner, Gerald W.; Labelle, Martine; Pietsch, Jacy; Ramsay, Malcolm; Schwartz, Charles; Titus, Kimberly; Williamson, Scott

2000-01-01

We analyzed 286 nucleotides of the middle portion of the mitochondrial cytochrome b gene of 61 brown bears from three locations in Alaska and 55 polar bears from Arctic Canada and Arctic Siberia to test our earlier observations of paraphyly between polar bears and brown bears as well as to test the extreme uniqueness of mitochondrial DNA types of brown bears on Admiralty, Baranof, and Chichagof (ABC) islands of southeastern Alaska. We also investigated the phylogeography of brown bears of Alaska's Kenai Peninsula in relation to other Alaskan brown bears because the former are being threatened by increased human development. We predicted that: (1) mtDNA paraphyly between brown bears and polar bears would be upheld, (2) the mtDNA uniqueness of brown bears of the ABC islands would be upheld, and (3) brown bears of the Kenai Peninsula would belong to either clade II or clade III of brown bears of our earlier studies of mtDNA. All of our predictions were upheld through the analysis of these additional samples.

The influence of regional Arctic sea-ice decline on stratospheric and tropospheric circulation

Science.gov (United States)

McKenna, Christine; Bracegirdle, Thomas; Shuckburgh, Emily; Haynes, Peter

2016-04-01

Arctic sea-ice extent has rapidly declined over the past few decades, and most climate models project a continuation of this trend during the 21st century in response to greenhouse gas forcing. A number of recent studies have shown that this sea-ice loss induces vertically propagating Rossby waves, which weaken the stratospheric polar vortex and increase the frequency of sudden stratospheric warmings (SSWs). SSWs have been shown to increase the probability of a negative NAO in the following weeks, thereby driving anomalous weather conditions over Europe and other mid-latitude regions. In contrast, other studies have shown that Arctic sea-ice loss strengthens the polar vortex, increasing the probability of a positive NAO. Sun et al. (2015) suggest these conflicting results may be due to the region of sea-ice loss considered. They find that if only regions within the Arctic Circle are considered in sea-ice projections, the polar vortex weakens; if only regions outwith the Arctic Circle are considered, the polar vortex strengthens. This is because the anomalous Rossby waves forced in the former/latter scenario constructively/destructively interfere with climatological Rossby waves, thus enhancing/suppressing upward wave propagation. In this study, we investigate whether Sun et al.'s results are robust to a different model. We also divide the regions of sea-ice loss they considered into further sub-regions, in order to examine the regional differences in more detail. We do this by using the intermediate complexity climate model, IGCM4, which has a well resolved stratosphere and does a good job of representing stratospheric processes. Several simulations are run in atmosphere only mode, where one is a control experiment and the others are perturbation experiments. In the control run annually repeating historical mean surface conditions are imposed at the lower boundary, whereas in each perturbation run the model is forced by SST perturbations imposed in a specific

Nutrient availability limits biological production in Arctic sea ice melt ponds

DEFF Research Database (Denmark)

Sørensen, Heidi Louise; Thamdrup, Bo; Jeppesen, Erik

2017-01-01

nutrient limitation in melt ponds. We also document that the addition of nutrients, although at relative high concentrations, can stimulate biological productivity at several trophic levels. Given the projected increase in first-year ice, increased melt pond coverage during the Arctic spring and potential......Every spring and summer melt ponds form at the surface of polar sea ice and become habitats where biological production may take place. Previous studies report a large variability in the productivity, but the causes are unknown. We investigated if nutrients limit the productivity in these first...... additional nutrient supply from, e.g. terrestrial sources imply that biological activity of melt ponds may become increasingly important for the sympagic carbon cycling in the future Arctic....

Arctic Synthesis Collaboratory: A Virtual Organization for Transformative Research and Education on a Changing Arctic

Science.gov (United States)

Warnick, W. K.; Wiggins, H. V.; Hinzman, L.; Holland, M.; Murray, M. S.; Vörösmarty, C.; Loring, A. J.

2008-12-01

-enabled model library, user forums, a data search and discovery system, and an online library. Support Scientist Professional Development: Experts at all career levels must keep pace with the newest developments in data integration and modeling, interdisciplinary science, and cyber-enabled collaboration. Specific project activities could include: web seminars, short courses, and a mentor program. Education, Outreach, and Policy Resources: An Arctic Virtual Outreach Center (AVOC) will provide critical education, outreach, and policy elements of the Collaboratory. Specific activities could include: public eSeminars, a virtual pressroom, K-12 classroom resources, and an eNewsletter. A Collaboratory Implementation Workshop is being planned for winter 2009; further details will be available soon. For more information, contact Helen V. Wiggins, Arctic Research Consortium of the U.S. (ARCUS) at: helen@arcus.org, or go to the website of the community workshop, "New Perspectives through Data Discovery and Modeling," at: http://www.arcus.org/ARCSS/2007_data/index.html.

Australian and Canadian perspectives and regulations for protecting the polar marine environment

Energy Technology Data Exchange (ETDEWEB)

Rothwell, Donald R.

1997-12-31

The report compares Australian and Canadian responses for protecting polar marine environments. Vast areas of the polar seas fall within their potential combined EEZ/continental shelf jurisdiction. The Antarctic Treaty provisions, doubts on the status of the Northwest Passage waters and the capacity to enforce legislative initiatives against foreign vessels have been constraints. Australia`s enactment of legislation prohibiting mining within the AAT continental shelf and whaling within the AAT EEZ has tested the Antarctic Treaty. Canada`s reaction to the Manhattan and the enactment of the Arctic Waters Pollution Prevention Act is an example of unilateral action. While the countries have made noteworthy initiatives to enhance the protection of their polar marine environments, doubts remain in some instances on their capacity to give effect to the initiatives. However, sovereignty remains at the heart of their response. Failure to address Antarctic marine environmental issues will rebound on the environment and reflect poorly upon Australia`s sovereignty claim to the AAT. For Canada it is a sovereignty issue and has directly impact upon its citizens inhabiting the islands and coastal areas of the Canadian Arctic. The Madrid Protocol provides the strongest legal basis for the Antarctic Treaty parties to enact laws and regulations in Antarctica. Conservation measures adopted under the Convention for the Conservation of Antarctic Marine Living Resources focuses increasingly on environmental concerns. The most significant regional initiative adopted by Arctic states is the AEPS which does not have a legal foundation. It`s co-operative programs provide basis for co-operation in dealing with environmental problems. It clearly recognises that only co-operative responses will achieve significant outcomes. The 1990s have posed new challenges for marine environmental protection such as ship-based tourism in Antarctica and the growing pressure to use the Northwest Passage on a

Moisture transport and Atmospheric circulation in the Arctic

Science.gov (United States)

Woods, Cian; Caballero, Rodrigo

2013-04-01

Arctic. We investigate an Arctic trajectory dataset and provide a phenomenological/descriptive analysis of these trajectories, including key meteorological variables carried along trajectories. The trajectory climatology is linked to a previously established cyclone climatology dataset from Hanley and Caballero (2011). We associate trajectories and the meteorological variables they are carrying to cyclones in this dataset. A climatology of 'Arctic-influencing' cyclones is constructed from the cyclone dataset. The resilience of the polar vortex and its effect on circulation, via blocking and breaking, is examined in relation to our trajectory climatology.

Three decades of BGR airborne geophysical surveys over the polar regions - a review

Science.gov (United States)

Damaske, Detlef

2013-04-01

smaller scale surveys - getting close to industry standards - targeted specific geological questions, the reconnaissance type of aerogeophysical projects continued in Dronning Maud Land, now in close cooperation with the Alfred-Wegener-Institute (AWI). This very successful cooperation between the two German institutions - both working continuously in the polar regions - was already established in Arctic projects, namely in northern Greenland. Also, since the late 1990's BGR conducted together with Canada airborne surveys as part of PMAP (Polar Margins Aeromagnetic Program), thematically linked to the predominantly geological CASE (Circum Arctic Structural Events) program of BGR. A joint project of GSC (Geological Survey of Canada) and BGR in the Nares Strait was a highlight of combined geological and aeromagnetic research addressing the still widely discussed Wegener fault between Greenland and Ellesmere Island and the extent of tertiary basins in the Nares Strait itself. BGR intends to continue its successful combined geological-geophysical work in both polar regions. The increasing logistic and financial challenges to work in these extreme areas will demand not only a continuation but an intensification of national and international collaboration.

Improvements to TOVS retrievals over sea ice and applications to estimating Arctic energy fluxes

Science.gov (United States)

Francis, Jennifer A.

1994-01-01

Modeling studies suggest that polar regions play a major role in modulating the Earth's climate and that they may be more sensitive than lower latitudes to climate change. Until recently, however, data from meteorological stations poleward of 70 degs have been sparse, and consequently, our understanding of air-sea-ice interaction processes is relatively poor. Satellite-borne sensors now offer a promising opportunity to observe polar regions and ultimately to improve parameterizations of energy transfer processes in climate models. This study focuses on the application of the TIROS-N operational vertical sounder (TOVS) to sea-ice-covered regions in the nonmelt season. TOVS radiances are processed with the improved initialization inversion ('3I') algorithm, providng estimates of layer-average temperature and moisture, cloud conditions, and surface characteristics at a horizontal resolution of approximately 100 km x 100 km. Although TOVS has flown continuously on polar-orbiting satellites since 1978, its potential has not been realized in high latitudes because the quality of retrievals is often significantly lower over sea ice and snow than over the surfaces. The recent availability of three Arctic data sets has provided an opportunity to validate TOVS retrievals: the first from the Coordinated Eastern Arctic Experiment (CEAREX) in winter 1988/1989, the second from the LeadEx field program in spring 1992, and the third from Russian drifting ice stations. Comparisons with these data reveal deficiencies in TOVS retrievals over sea ice during the cold season; e.g., ice surface temperature is often 5 to 15 K too warm, microwave emissivity is approximately 15% too low at large view angles, clear/cloudy scenes are sometimes misidentified, and low-level inversions are often not captured. In this study, methods to reduce these errors are investigated. Improvements to the ice surface temperature retrieval have reduced rms errors from approximately 7 K to 3 K; correction of

Tracer-tracer relations as a tool for research on polar ozone loss

Energy Technology Data Exchange (ETDEWEB)

Mueller, Rolf

2010-07-01

The report includes the following chapters: (1) Introduction: ozone in the atmosphere, anthropogenic influence on the ozone layer, polar stratospheric ozone loss; (2) Tracer-tracer relations in the stratosphere: tracer-tracer relations as a tool in atmospheric research; impact of cosmic-ray-induced heterogeneous chemistry on polar ozone; (3) quantifying polar ozone loss from ozone-tracer relations: principles of tracer-tracer correlation techniques; reference ozone-tracer relations in the early polar vortex; impact of mixing on ozone-tracer relations in the polar vortex; impact of mesospheric intrusions on ozone-tracer relations in the stratospheric polar vortex calculation of chemical ozone loss in the arctic in March 2003 based on ILAS-II measurements; (4) epilogue.

Poles apart: the "bipolar" pteropod species Limacina helicina is genetically distinct between the Arctic and Antarctic oceans.

Science.gov (United States)

Hunt, Brian; Strugnell, Jan; Bednarsek, Nina; Linse, Katrin; Nelson, R John; Pakhomov, Evgeny; Seibel, Brad; Steinke, Dirk; Würzberg, Laura

2010-03-23

The shelled pteropod (sea butterfly) Limacina helicina is currently recognised as a species complex comprising two sub-species and at least five "forma". However, at the species level it is considered to be bipolar, occurring in both the Arctic and Antarctic oceans. Due to its aragonite shell and polar distribution L. helicina is particularly vulnerable to ocean acidification. As a key indicator of the acidification process, and a major component of polar ecosystems, L. helicina has become a focus for acidification research. New observations that taxonomic groups may respond quite differently to acidification prompted us to reassess the taxonomic status of this important species. We found a 33.56% (+/-0.09) difference in cytochrome c oxidase subunit I (COI) gene sequences between L. helicina collected from the Arctic and Antarctic oceans. This degree of separation is sufficient for ordinal level taxonomic separation in other organisms and provides strong evidence for the Arctic and Antarctic populations of L. helicina differing at least at the species level. Recent research has highlighted substantial physiological differences between the poles for another supposedly bipolar pteropod species, Clione limacina. Given the large genetic divergence between Arctic and Antarctic L. helicina populations shown here, similarly large physiological differences may exist between the poles for the L. helicina species group. Therefore, in addition to indicating that L. helicina is in fact not bipolar, our study demonstrates the need for acidification research to take into account the possibility that the L. helicina species group may not respond in the same way to ocean acidification in Arctic and Antarctic ecosystems.

Enabling Use of Unmanned Aircraft Systems for Arctic Environmental Monitoring

DEFF Research Database (Denmark)

Storvold, Rune; la Cour-Harbo, Anders; Mulac, Brenda

, technical and logistical challenges facing scientists intending to use UAS in their arctic work. Future planned campaigns and science goals under the Coordinated Investigation of Climate-Cryosphere Interactions (CICCI) umbrella will be outlined. A new AMAP report on conducting safe UAS operations......, poor resolution, and the complicated surface of snow and ice. Measurements made from manned aircraft are also limited because of range and endurance, as well as the danger and costs presented by operating manned aircraft in harsh and remote environments like the Arctic. Unmanned aircraft systems (UAS...... on the environment. Operating UAS present unique challenges and it is necessary to understand and overcome those challenges. Based on the recommendations put forth by the Arctic scientists, the Arctic Council created a UAS Expert Group under the Arctic Monitoring and Assessment Program (AMAP) to help address...

Ship emissions measurement in the Arctic by plume intercepts of the Canadian Coast Guard icebreaker Amundsen from the Polar 6 aircraft platform

Directory of Open Access Journals (Sweden)

A. A. Aliabadi

2016-06-01

Full Text Available Decreasing sea ice and increasing marine navigability in northern latitudes have changed Arctic ship traffic patterns in recent years and are predicted to increase annual ship traffic in the Arctic in the future. Development of effective regulations to manage environmental impacts of shipping requires an understanding of ship emissions and atmospheric processing in the Arctic environment. As part of the summer 2014 NETCARE (Network on Climate and Aerosols campaign, the plume dispersion and gas and particle emission factors of effluents originating from the Canadian Coast Guard icebreaker Amundsen operating near Resolute Bay, NU, Canada, were investigated. The Amundsen burned distillate fuel with 1.5 wt % sulfur. Emissions were studied via plume intercepts using the Polar 6 aircraft measurements, an analytical plume dispersion model, and using the FLEXPART-WRF Lagrangian particle dispersion model. The first plume intercept by the research aircraft was carried out on 19 July 2014 during the operation of the Amundsen in the open water. The second and third plume intercepts were carried out on 20 and 21 July 2014 when the Amundsen had reached the ice edge and operated under ice-breaking conditions. Typical of Arctic marine navigation, the engine load was low compared to cruising conditions for all of the plume intercepts. The measured species included mixing ratios of CO2, NOx, CO, SO2, particle number concentration (CN, refractory black carbon (rBC, and cloud condensation nuclei (CCN. The results were compared to similar experimental studies in mid-latitudes. Plume expansion rates (γ were calculated using the analytical model and found to be γ  =  0.75 ± 0.81, 0.93 ± 0.37, and 1.19 ± 0.39 for plumes 1, 2, and 3, respectively. These rates were smaller than prior studies conducted at mid-latitudes, likely due to polar boundary layer dynamics, including reduced turbulent mixing compared to mid-latitudes. All emission

Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: M_MAMPT (Marine Mammal Points)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for Steller sea lions and polar bears in Northwest Arctic, Alaska. Vector points in this data set represent...

DNA-based and culture-based characterization of a hydrocarbon-degrading consortium enriched from Arctic soil

Energy Technology Data Exchange (ETDEWEB)

Thomassin-Lacroix, E. J. M.; Reimer, K. J. [Royal Military College, Dept. of Chemistry and Chemical Engineering, Kingston, On (Canada); Yu, Z.; Mohn, W. W. [British Columbia Univ., Dept. of Microbiology and Immunology, Vancouver, BC (Canada); Eriksson, M. [Royal Inst. of Technology, Dept. of Biotechnology, Stockholm (Sweden)

2001-12-01

Oil spills are fairly common in polar tundra regions, including remote locations, and are a threat to the relatively fragile ecosystem. Remediation must be done economically and with minimum additional damage. Bioremediation is considered to be the appropriate technology, although its application in polar tundra regions is not well documented. Most studies of hydrocarbon remediation in polar regions have concerned marine oil spills, while a few studies have demonstrated on-site polar tundra soil remediation. A few of these demonstrated the presence of psychrotolerant hydrocarbon-degrading bacteria in polar tundra soils. Because fuels are complex mixtures of hydrocarbons, microbial consortia rather than pure cultures may be the most effective agents in degrading fuels. Despite their potential advantages for bioaugmentation applications, consortia are difficult to characterize and monitor. Molecular methods based on DNA analysis partially address these difficulties. One such approach is to randomly clone rRNA gene (rDNA) fragments and to sequence as a set of clones. The relative abundance of individual sequences in the clone library is related to the relative abundance of the corresponding organism in the community. In this study a psychrotolerant, fuel-degrading consortium was enriched with Arctic tundra soil. The enrichment substrate for the consortium was Jet A-1 fuel, which is very similar to Arctic diesel fuel, a common contaminant in the region. The objectives of the study were to (1) characterize thr consortium by DNA- and culture-based methods, (2) develop quantitative polymerase chain reaction assays for populations of predominant consortium members, and (3) determine the dynamics of those populations during incubation of the consortium. Result showed that is possible to quantitatively monitor members of a microbial consortium, with potential application for bioremediation of Arctic tundra soil. The relative abundance of consortium members was found to vary

Trichinella and polar bears: a limited risk for humans.

Science.gov (United States)

Dupouy-Camet, J; Bourée, P; Yera, H

2017-07-01

In this review, we identified 63 cases reported since World War II of human trichinellosis linked to the consumption of parasitized polar bear (Ursus maritimus) meat. This low number contrasts to the numerous cases of human trichinellosis related to consumption of the meat of black (U. americanus) or brown bears (U. arctos). The prevalence of Trichinella infection is high in bears, but larval muscular burden is usually lower in polar bears compared to other bear species. Polar bears, therefore, seem to play a limited role in the transmission of trichinellosis to humans, as native residents living in the Arctic traditionally consume well-cooked bear meat, and travellers and foreign hunters have only limited access to this protected species due to the declining polar bear population.

Overview of human health in the Arctic: conclusions and recommendations.

Science.gov (United States)

Donaldson, Shawn; Adlard, Bryan; Odland, Jon Øyvind

2016-01-01

This article is intended to provide an overview of the key conclusions, knowledge gaps and key recommendations based on the recent 2015 Arctic human health assessment under the Arctic Monitoring and Assessment Program. This assessment was based primarily on data from human health monitoring and research studies and peer-reviewed literature published since the last assessment in 2009.

Changes in the Arctic: Background and Issues for Congress

Science.gov (United States)

2016-12-07

Arctic accidents and incidents in the past. The U.S. Army Corps of Engineers , along with the state of Alaska, is studying the feasibility of a... aeronautical and maritime search and rescue for each party. For the United States , those agencies are the Coast Guard and the Department of Defense...purchased from Ukraine a research icebreaker it named the Xuelong, and has constructed a state -of-the- art polar capable research vessel, the Snow Dragon

Evaluating and ranking threats to the long-term persistence of polar bears

Science.gov (United States)

Atwood, Todd C.; Marcot, Bruce G.; Douglas, David C.; Amstrup, Steven C.; Rode, Karyn D.; Durner, George M.; Bromaghin, Jeffrey F.

2015-01-01

The polar bear (Ursus maritimus) was listed as a globally threatened species under the U.S. Endangered Species Act (ESA) in 2008, mostly due to the significant threat to their future population viability from rapidly declining Arctic sea ice. A core mandate of the ESA is the development of a recovery plan that identifies steps to maintain viable populations of a listed species. A substantive evaluation of the relative influence of putative threats to population persistence is helpful to recovery planning. Because management actions must often be taken in the face of substantial information gaps, a formalized evaluation hypothesizing potential stressors and their relationships with population persistence can improve identification of relevant conservation actions. To this end, we updated a Bayesian network model previously used to forecast the future status of polar bears worldwide. We used new information on actual and predicted sea ice loss and polar bear responses to evaluate the relative influence of plausible threats and their mitigation through management actions on the persistence of polar bears in four ecoregions. We found that polar bear outcomes worsened over time through the end of the century under both stabilized and unabated greenhouse gas (GHG) emission pathways. Under the unabated pathway (i.e., RCP 8.5), the time it took for polar bear populations in two of four ecoregions to reach a dominant probability of greatly decreased was hastened by about 25 years. Under the stabilized GHG emission pathway (i.e., RCP 4.5), where GHG emissions peak around the year 2040, the polar bear population in the Archipelago Ecoregion of High Arctic Canada never reached a dominant probability of greatly decreased, reinforcing earlier suggestions of this ecoregion’s potential to serve as a long-term refugium. The most influential drivers of adverse polar bear outcomes were declines to overall sea ice conditions and to the marine prey base. Improved sea ice conditions

Bacterial communities in ancient permafrost profiles of Svalbard, Arctic.

Science.gov (United States)

Singh, Purnima; Singh, Shiv M; Singh, Ram N; Naik, Simantini; Roy, Utpal; Srivastava, Alok; Bölter, Manfred

2017-12-01

Permafrost soils are unique habitats in polar environment and are of great ecological relevance. The present study focuses on the characterization of bacterial communities from permafrost profiles of Svalbard, Arctic. Counts of culturable bacteria range from 1.50 × 10 3 to 2.22 × 10 5 CFU g -1 , total bacterial numbers range from 1.14 × 10 5 to 5.52 × 10 5 cells g -1 soil. Bacterial isolates are identified through 16S rRNA gene sequencing. Arthrobacter and Pseudomonas are the most dominant genera, and A. sulfonivorans, A. bergeri, P. mandelii, and P. jessenii as the dominant species. Other species belong to genera Acinetobacter, Bacillus, Enterobacter, Nesterenkonia, Psychrobacter, Rhizobium, Rhodococcus, Sphingobacterium, Sphingopyxis, Stenotrophomonas, and Virgibacillus. To the best of our knowledge, genera Acinetobacter, Enterobacter, Nesterenkonia, Psychrobacter, Rhizobium, Sphingobacterium, Sphingopyxis, Stenotrophomonas, and Virgibacillus are the first northernmost records from Arctic permafrost. The present study fills the knowledge gap of culturable bacterial communities and their chronological characterization from permafrost soils of Ny-Ålesund (79°N), Arctic. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Determination of a Critical Sea Ice Thickness Threshold for the Central Arctic Ocean

Science.gov (United States)

Ford, V.; Frauenfeld, O. W.; Nowotarski, C. J.

2017-12-01

While sea ice extent is readily measurable from satellite observations and can be used to assess the overall survivability of the Arctic sea ice pack, determining the spatial variability of sea ice thickness remains a challenge. Turbulent and conductive heat fluxes are extremely sensitive to ice thickness but are dominated by the sensible heat flux, with energy exchange expected to increase with thinner ice cover. Fluxes over open water are strongest and have the greatest influence on the atmosphere, while fluxes over thick sea ice are minimal as heat conduction from the ocean through thick ice cannot reach the atmosphere. We know that turbulent energy fluxes are strongest over open ocean, but is there a "critical thickness of ice" where fluxes are considered non-negligible? Through polar-optimized Weather Research and Forecasting model simulations, this study assesses how the wintertime Arctic surface boundary layer, via sensible heat flux exchange and surface air temperature, responds to sea ice thinning. The region immediately north of Franz Josef Land is characterized by a thickness gradient where sea ice transitions from the thickest multi-year ice to the very thin marginal ice seas. This provides an ideal location to simulate how the diminishing Arctic sea ice interacts with a warming atmosphere. Scenarios include both fixed sea surface temperature domains for idealized thickness variability, and fixed ice fields to detect changes in the ocean-ice-atmosphere energy exchange. Results indicate that a critical thickness threshold exists below 1 meter. The threshold is between 0.4-1 meters thinner than the critical thickness for melt season survival - the difference between first year and multi-year ice. Turbulent heat fluxes and surface air temperature increase as sea ice thickness transitions from perennial ice to seasonal ice. While models predict a sea ice free Arctic at the end of the warm season in future decades, sea ice will continue to transform

NOAA Climate Data Record (CDR) of AVHRR Polar Pathfinder Extended (APP-X) Cryosphere

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Climate Data Record (CDR) of the extended AVHRR Polar Pathfinder (APP-x) cryosphere contains 19 geophysical variables over the Arctic and Antarctic for the...

Scientific Discoveries in the Central Arctic Ocean Based on Seafloor Mapping Carried out to Support Article 76 Extended Continental Shelf Claims (Invited)

Science.gov (United States)

Jakobsson, M.; Mayer, L. A.; Marcussen, C.

2013-12-01

Despite the last decades of diminishing sea-ice cover in the Arctic Ocean, ship operations are only possible in vast sectors of the central Arctic using the most capable polar-class icebreakers. There are less than a handful of these icebreakers outfitted with modern seafloor mapping equipment. This implies either fierce competition between those having an interest in using these icebreakers for investigations of the shape and properties of Arctic Ocean seafloor or, preferably, collaboration. In this presentation examples will be shown of scientific discoveries based on mapping data collected during Arctic Ocean icebreaker expeditions carried out for the purpose of substantiating claims for an extended continental shelf under United Nations Convention of the Law of the Sea (UNCLOS) Article 76. Scientific results will be presented from the suite of Lomonosov Ridge off Greenland (LOMROG) expeditions (2007, 2009, and 2012), shedding new light on Arctic Ocean oceanography and glacial history. The Swedish icebreaker Oden was used in collaboration between Sweden and Denmark during LOMROG to map and sample portions of the central Arctic Ocean; specifically focused on the Lomonosov Ridge north of Greenland. While the main objective of the Danish participation was seafloor and sub-seabed mapping to substantiate their Article 76 claim, LOMROG also included several scientific components, with scientists from both countries involved. Other examples to be presented are based on data collected using US Coast Guard Cutter Healy, which for several years has carried out mapping in the western Arctic Ocean for the US continental shelf program. All bathymetric data collected with Oden and Healy have been contributed to the International Bathymetric Chart of the Arctic Ocean (IBCAO). This is also the case for bathymetric data collected by Canadian Coast Guard Ship Louis S. St-Laurent for Canada's extended continental shelf claim. Together, the bathymetric data collected during these

Facets of Arctic energy accumulation based on observations and reanalyses 2000-2015.

Science.gov (United States)

Mayer, Michael; Haimberger, Leopold; Pietschnig, Marianne; Storto, Andrea

2016-10-16

Various observation- and reanalysis-based estimates of sea ice mass and ocean heat content trends imply that the energy imbalance of the Arctic climate system was similar [1.0 (0.9,1.2) Wm -2 ] to the global ocean average during the 2000-2015 period. Most of this extra heat warmed the ocean, and a comparatively small fraction went into sea ice melt. Poleward energy transports and radiation contributed to this energy increase at varying strengths. On a seasonal scale, stronger radiative energy input during summer associated with the ice-albedo feedback enhances seasonal oceanic heat uptake and sea ice melt. In return, lower sea ice extent and higher sea surface temperatures lead to enhanced heat release from the ocean during fall. This weakens meridional temperature gradients, consequently reducing atmospheric energy transports into the polar cap. The seasonal cycle of the Arctic energy budget is thus amplified, whereas the Arctic's long-term energy imbalance is close to the global mean.

Economic Valuation of Ecosystem Goods and Services in a Melting Arctic

Science.gov (United States)

O'Garra, T.

2014-12-01

The Arctic region is composed of unique ecosystems that provide a range of goods and services to local and global populations. However, Arctic sea-ice is melting at an unprecedented rate, threatening many of these ecosystems and the services they provide. Yet as the ice melts and certain goods and services are lost, other resources such as oil and minerals will become accessible. The question is: how do the losses compare with the opportunities? And how are the losses and potential gains likely to be distributed? To address these questions, this study provides a preliminary assessment of the quantity, distribution and economic value of the ecosystem services (ES) provided by Arctic ecosystems, both now and in the future given a scenario of sure climate change. Using biophysical and economic data from existing studies (and some primary data), preliminary estimates indicate that the Arctic currently provides 357m/yr (in 2014 US) in subsistence hunting value to local communities, of which reindeer/caribou comprise 83%. Reindeer herding provides 110m/yr to Arctic communities. Interestingly, 'non-use (existence/cultural) values' associated with Arctic species are very high at 11bn/yr to members of Arctic states. The Arctic also provides ES that accrue to the global community: oil resources (North Slope; 5bn profits in 2013), commercial fisheries ( 515mn/yr) and most importantly, climate regulation services. Recent models (Whiteman; Euskirchen) estimate that the loss of climate regulation services provided by Arctic ice will cost 200 - 500bn/yr, a value which dwarfs all others. Assuming no change in atmospheric temperature compared to 2014, the net present value of the Arctic by 2050 (1.4% discount rate) comes to over $9 trillion. However, given Wang and Overland (2009) predictions of ice-free summers by 2037, we expect many of these benefits will be lost. For example, it is fairly well-established that endemic species, such as polar bears, will decline with sea-ice melt

Ancient hybridization and an Irish origin for the modern polar bear matriline

DEFF Research Database (Denmark)

Edwards, Ceiridwen J.; Suchard, Marc A.; Lemey, Philippe

2011-01-01

Polar bears (Ursus maritimus) are among those species most susceptible to the rapidly changing arctic climate, and their survival is of global concern. Despite this, little is known about polar bear species history. Future conservation strategies would significantly benefit from an understanding...... of basic evolutionary information, such as the timing and conditions of their initial divergence from brown bears (U. arctos) or their response to previous environmental change....

Steroid hormone profile in female polar bears (Ursus maritimus)

DEFF Research Database (Denmark)

Gustavson, Lisa; Jenssen, Bjørn Munro; Bytingsvik, Jenny

2015-01-01

The polar bear is an iconic Arctic species, threatened by anthropogenic impacts such as pollution and climate change. Successful reproduction of polar bears depends on a functioning steroid hormone system, which is susceptible to effects of persistent organic pollutants. The present study...... is the first study to report circulating concentrations of nine steroid hormones (i.e., estrogens, androgens and progestagens) in female polar bears (Ursus maritimus). The aim of the study was to investigate the effects of age, condition, location and reproductive status on steroid profile in female polar...... bears. Levels of pregnenolone (PRE), progesterone, androstenedione (AN), dehydroepiandrosterone (DHEA), testosterone, dihydrotestosterone, estrone (E1), 17α-estradiol (αE2) and 17β-estradiol (βE2) were quantified in blood (serum) of free-living female polar bears (n = 15) from Svalbard, Norway, by gas...

New York City International Polar Weekend at the American Museum of Natural History

Science.gov (United States)

Pfirman, S.; Turrin, M.; Macphee, R.

2008-12-01

The American Museum of Natural History, in partnership with Lamont-Doherty Earth Observatory and the Earth Institute of Columbia University and Barnard College, is featuring the International Polar Year through a New York City International Polar Weekend (NYC-IPW) in 2007, 2008 and 2009. The event showcases current polar research, polar environmental changes, history and culture during two days of family programs and activities, performances, and lectures. The goal of the NYC-IPW is to engage diverse audiences and enhance the public understanding of polar science, in particular IPY research, through close interactions with polar experts. Activities for the public include many disciplines, ranging from the physical sciences and cultural anthropology to music and art, and are presented in many forms, from lectures, panels and films to posters and play. Highlights of the NYC-IPW include: 1) A polar fair for youth and adults, showcasing scientists, artists, and educators who have worked at one or both poles and including many interactive exhibits featuring such topics as life in New York at the end of the last Ice Age, how Arctic sea ice is changing, and life on and under the ice. 2) Performances and presentations oriented towards children and families, including Inuit Throat Singers, Central Park Zoo Theater Group, and a northern lights show. 3) Lectures showcasing current IPY research and addressing such issues as the possible effects of climate change on the poles and the rest of the world, as well as polar poetry, art and film. 4) A partnership with New York City Urban Advantage program for Middle School students in the city to meet with scientists, teachers and students who had participated in polar research and travel. 5) Norwegian Consulate sponsorship of science presenters and Sami performers. The March 2007 event involved 85 presenters and volunteers from 22 institutions, and attracted ca. 3,500 visitors. Approximately 5,000 visitors attended the February 2008

Heroism and Imperialism in the Arctic: Edwin Landseer’s Man Proposes – God Disposes

Directory of Open Access Journals (Sweden)

Ingeborg Høvik

2008-02-01

Full Text Available Edwin Landseer contributed the painting Man Proposes - God Disposes (Royal Holloway College, Egham, showing two polar bears amongst the remnants of a failed Arctic expedition, to the Royal Academy's annual exhibition of 1864. As contemporary nineteenth-century reviews of this exhibition show, the British public commonly associated Landseer's painting with the lost Arctic expedition of sir John Franklin, who had set out to find the Northwest Passage in 1845. Despite Landseer's gloomy representation of a present-day human disaster and, in effect, of British exploration in the Arctic, the painting became a public success upon its first showing. I will argue that a major reason why the painting became a success, was because Landseer's version of the Franklin expedition's fate offered a closure to the whole Franklin tragedy that corresponded to British nineteenth-century views on heroism and British-ness.

What is happening in the International Polar Year? Latest news about the climate changes

International Nuclear Information System (INIS)

Orheim, Olav

2008-01-01

The International Polar (IPY) Year 2007-2008 is a large scientific programme focused on the Arctic and the Antarctic. Scientists from over 60 nations participates. The IPY have two primary objectives: to improve weather forecasts especially regarding extreme weather and to improve climatic models for better understanding of possible instabilities, especially regarding ocean currents. The presentation includes data on natural climate change, temperature anomaly, the ice in the Arctic Ocean and Northern and Southern Hemisphere sea ice area, current in Southern and Northern hemisphere sea ice area and variations of the surface temperature ice arctic regions antarctic regions. The presentation was held at the MNT-Forum, 29. January 2008

Consequences of long-distance swimming and travel over deep-water pack ice for a female polar bear during a year of extreme sea ice retreat

Science.gov (United States)

Durner, George M.; Whiteman, J.P.; Harlow, H.J.; Amstrup, Steven C.; Regehr, E.V.; Ben-David, M.

2011-01-01

Polar bears (Ursus maritimus) prefer to live on Arctic sea ice but may swim between ice floes or between sea ice and land. Although anecdotal observations suggest that polar bears are capable of swimming long distances, no data have been available to describe in detail long distance swimming events or the physiological and reproductive consequences of such behavior. Between an initial capture in late August and a recapture in late October 2008, a radio-collared adult female polar bear in the Beaufort Sea made a continuous swim of 687 km over 9 days and then intermittently swam and walked on the sea ice surface an additional 1,800 km. Measures of movement rate, hourly activity, and subcutaneous and external temperature revealed distinct profiles of swimming and walking. Between captures, this polar bear lost 22% of her body mass and her yearling cub. The extraordinary long distance swimming ability of polar bears, which we confirm here, may help them cope with reduced Arctic sea ice. Our observation, however, indicates that long distance swimming in Arctic waters, and travel over deep water pack ice, may result in high energetic costs and compromise reproductive fitness.

Are liver and renal lesions in East Greenland polar bears (Ursus maritimus associated with high mercury levels?

Directory of Open Access Journals (Sweden)

Born Erik W

2007-04-01

Full Text Available Abstract Background In the Arctic, polar bears (Ursus maritimus bio-accumulate mercury as they prey on polluted ringed seals (Phoca hispida and bearded seals (Erignathus barbatus. Studies have shown that polar bears from East Greenland are among the most mercury polluted species in the Arctic. It is unknown whether these levels are toxic to liver and kidney tissue. Methods We investigated the histopathological impact from anthropogenic long-range transported mercury on East Greenland polar bear liver (n = 59 and kidney (n = 57 tissues. Results Liver mercury levels ranged from 1.1–35.6 μg/g wet weight and renal levels ranged from 1–50 μg/g wet weight, of which 2 liver values and 9 kidney values were above known toxic threshold level of 30 μg/g wet weight in terrestrial mammals. Evaluated from age-correcting ANCOVA analyses, liver mercury levels were significantly higher in individuals with visible Ito cells (p Conclusion Based on these relationships and the nature of the chronic inflammation we conclude that the lesions were likely a result of recurrent infections and ageing but that long-term exposure to mercury could not be excluded as a co-factor. The information is important as it is likely that tropospheric mercury depletion events will continue to increase the concentrations of this toxic heavy metal in the Sub Arctic and Arctic marine food webs.

Redevelopment of the Arctic Area of Russia as an Objective of Systems Research and Special-Purpose Program Management Methodological Issues

Directory of Open Access Journals (Sweden)

Vladimir Nikolayevich Leksin

2015-12-01

Full Text Available The paper substantiates the methodological foundations of implementation of the rules and regulations of the development of the Arctic region of Russia, which relies on the hypothesis interpreting such development as the biggest integrated megaproject in the history of Russia. The substantiation involves both the project-oriented approach to identify the subject-matter of the research and the systems approach to assess the key opportunities of providing the integrative structure of the megaproject in the conditions of drastic differences between the areal components of the Arctic region, and to study the internal and external factors’ impact on the character, drivers and pace of the region redevelopment. The set of consistent methodological positions concerning their policy implementation by responsible governmental agencies in the foreseeable future of the Arctic is developed. The most important position involves the identification of the objective of the public administration of the Arctic region development as a systemically organized entity of multiple coordinated actions of the federal, regional and municipal authorities, corporations and civil society institutions integrated by the unique policy target and economic, social and infrastructure links. Implementation of the public administration requires the principles of systems approach, the reasonable trade-off between centralization, decentralization and continuity of governance focused exclusively on the Arctic issues. At the same time, the integration of the projects of the region’s areal components development to insure the common targets of the Arctic’s megaproject accompanied by the reconsideration of the earlier developed programs turns into a genuinely new methodological issue. In the article, recommendations to provide such integration are introduced.

Atmospheric Circulation Response to Episodic Arctic Warming in an Idealized Model

Science.gov (United States)

Hell, M. C.; Schneider, T.; Li, C.

2017-12-01

Recent Arctic sea ice loss has drawn attention as a potential driver of fall/winter circulation changes. Past work has shown that sea ice loss can be related to a stratospheric polar vortex breakdown, with the result of long-delayed surface weather phenomena in late winter/early spring. In this study, we separate the atmospheric dynamic components and mean timescales to episodic polar surface heat fluxes using large ensembles of an idealized GCM in absence of continents and seasons. The atmospheric ensemble-mean response is linear related to the surface forcing strength and insensitive to the forcing symmetry. Analyses in the Transformed Eulerian Mean show that the responses can be separated into 1) an in-phase thermal adjustment, and 2) a lagged, eddy-driven component invoking long-standing anomalies in the lower stratosphere. The mid-latitude adjustment to the episodically reduced baroclinity leads to stratosphere-directed eddy-heat fluxes, establishing a stratospheric temperature anomaly responsible for vortex break down. In addition, we discuss the dependence on the background state via correlation in ensemble member space. Thus, we range the role of arctic perturbations in the transient large-scale circulation.

Diversifying the Geosciences: Examples from the Arctic

Science.gov (United States)

Holmes, R. M.

2017-12-01

Like other realms of the geosciences, the scientists who comprise the Arctic research community tends to be white and male. For example, a survey of grants awarded over a 5-year period beginning in 2010 by NSF's Arctic System Science and Arctic Natural Sciences programs showed that over 90% of PIs were white whereas African Americans, Hispanics, and Native Americans together accounted for only about 1% of PIs. Over 70% of the PIs were male. I will suggest that involving diverse upper-level undergraduate students in authentic field research experiences may be one of the shortest and surest routes to diversifying the Arctic research community, and by extension, the geoscientific research community overall. Upper-level undergraduate students are still open to multiple possibilities, but an immersive field research experience often helps solidify graduate school and career trajectories. Though an all-of-the-above strategy is needed, focusing on engaging a diverse cohort of upper-level undergraduate students may provide one of the most efficient means of diversifying the geosciences over the coming years and decades.

Cloud-Scale Numerical Modeling of the Arctic Boundary Layer

Science.gov (United States)

Krueger, Steven K.

1998-01-01

The interactions between sea ice, open ocean, atmospheric radiation, and clouds over the Arctic Ocean exert a strong influence on global climate. Uncertainties in the formulation of interactive air-sea-ice processes in global climate models (GCMs) result in large differences between the Arctic, and global, climates simulated by different models. Arctic stratus clouds are not well-simulated by GCMs, yet exert a strong influence on the surface energy budget of the Arctic. Leads (channels of open water in sea ice) have significant impacts on the large-scale budgets during the Arctic winter, when they contribute about 50 percent of the surface fluxes over the Arctic Ocean, but cover only 1 to 2 percent of its area. Convective plumes generated by wide leads may penetrate the surface inversion and produce condensate that spreads up to 250 km downwind of the lead, and may significantly affect the longwave radiative fluxes at the surface and thereby the sea ice thickness. The effects of leads and boundary layer clouds must be accurately represented in climate models to allow possible feedbacks between them and the sea ice thickness. The FIRE III Arctic boundary layer clouds field program, in conjunction with the SHEBA ice camp and the ARM North Slope of Alaska and Adjacent Arctic Ocean site, will offer an unprecedented opportunity to greatly improve our ability to parameterize the important effects of leads and boundary layer clouds in GCMs.

Emission Changes Dwarf the Influence of Feeding Habits on Temporal Trends of Per- and Polyfluoroalkyl Substances in Two Arctic Top Predators.

Science.gov (United States)

Routti, Heli; Aars, Jon; Fuglei, Eva; Hanssen, Linda; Lone, Karen; Polder, Anuschka; Pedersen, Åshild Ø; Tartu, Sabrina; Welker, Jeffrey M; Yoccoz, Nigel G

2017-10-17

We monitored concentrations of per- and polyfluoroalkyl substances (PFASs) in relation to climate-associated changes in feeding habits and food availability in polar bears (Ursus maritimus) and arctic foxes (Vulpes lagopus) (192 plasma and 113 liver samples, respectively) sampled from Svalbard, Norway, during 1997-2014. PFASs concentrations became greater with increasing dietary trophic level, as bears and foxes consumed more marine as opposed to terrestrial food, and as the availability of sea ice habitat increased. Long-chained perfluoroalkyl carboxylates (PFCAs) in arctic foxes decreased with availability of reindeer carcasses. The ∼9-14% yearly decline of C 6-8 perfluoroalkyl sulfonates (PFSAs) following the cease in C 6-8 PFSA precursor production in 2001 indicates that the peak exposure was mainly a result of atmospheric transport of the volatile precursors. However, the stable PFSA concentrations since 2009-2010 suggest that Svalbard biota is still exposed to ocean-transported PFSAs. Long-chain ocean-transported PFCAs increased 2-4% per year and the increase in C 12-14 PFCAs in polar bears tended to level off since ∼2009. Emerging short-chain PFASs showed no temporal changes. Climate-related changes in feeding habits and food availability moderately affected PFAS trends. Our results indicate that PFAS concentrations in polar bears and arctic foxes are mainly affected by emissions.

Bringing Society to a Changing Polar Ocean: Polar Interdisciplinary Coordinated Education (ICE)

Science.gov (United States)

Schofield, O.

2015-12-01

Environmental changes in the Arctic and Antarctic appear to be accelerating and scientists are trying to understand both the patterns and the impacts of change. These changes will have profound impact on humanity and create a need for public education about these critical habitats. We have focused on a two-pronged strategy to increase public awareness as well as enable educators to discuss comfortably the implications of climate change. Our first focus is on entraining public support through the development of science documentaries about the science and people who conduct it. Antarctic Edge is a feature length award-winning documentary about climate change that has been released in May 2015 and has garnered interest in movie theatres and on social media stores (NetFlix, ITunes). This broad outreach is coupled with our group's interest assisting educators formally. The majority of current polar education is focused on direct educator engagement through personal research experiences that have impact on the participating educators' classrooms. Polar Interdisciplinary Coordinated Education (ICE) proposes to improve educator and student engagement in polar sciences through exposure to scientists and polar data. Through professional development and the creation of data tools, Polar ICE will reduce the logistical costs of bringing polar science to students in grades 6-16. We will provide opportunities to: 1) build capacity of polar scientists in communicating and engaging with diverse audiences; 2) create scalable, in-person and virtual opportunities for educators and students to engage with polar scientists and their research through data visualizations, data activities, educator workshops, webinars, and student research symposia; and 3) evaluate the outcomes of Polar ICE and contribute to our understanding of science education practices. We will use a blended learning approach to promote partnerships and cross-disciplinary sharing. This combined multi-pronged approach

Circumpolar measurements of speciated mercury, ozone and carbon monoxide in the boundary layer of the Arctic Ocean

Science.gov (United States)

Sommar, J.; Andersson, M. E.; Jacobi, H.-W.

2010-06-01

Using the Swedish icebreaker Oden as a platform, continuous measurements of airborne mercury (gaseous elemental mercury (Hg0), divalent gaseous mercury species HgIIX2(g) (acronym RGM) and mercury attached to particles (PHg)) and some long-lived trace gases (carbon monoxide CO and ozone O3) were performed over the North Atlantic and the Arctic Ocean. The measurements were performed for nearly three months (July-September 2005) during the Beringia 2005 expedition (from Göteborg, Sweden via the proper Northwest Passage to the Beringia region Alaska - Chukchi Penninsula - Wrangel Island and in-turn via a north-polar transect to Longyearbyen, Spitsbergen). The Beringia 2005 expedition was the first time that these species have been measured during summer over the Arctic Ocean going from 60° to 90° N. During the North Atlantic transect, concentration levels of Hg0, CO and O3 were measured comparable to typical levels for the ambient mid-hemispheric average. However, a rapid increase of Hg0 in air and surface water was observed when entering the ice-covered waters of the Canadian Arctic archipelago. Large parts of the measured waters were supersaturated with respect to Hg0, reflecting a strong disequilibrium. Heading through the sea ice of the Arctic Ocean, a fraction of the strong Hg0 pulse in the water was transferred with some time-delay into the air samples collected ~20 m above sea level. Several episodes of elevated Hg0 in air were encountered along the sea ice route with higher mean concentration (1.81±0.43 ng m-3) compared to the marine boundary layer over ice-free Arctic oceanic waters (1.55±0.21 ng m-3). In addition, the bulk of the variance in the temporal series of Hg0 concentrations was observed during July. The Oden Hg0 observations compare in this aspect very favourably with those at the coastal station Alert. Atmospheric boundary layer O3 mixing ratios decreased when initially sailing northward. In the Arctic, an O3 minimum around 15-20 ppbV was

Arctic Intermediate Water in the Nordic Seas, 1991-2009

Science.gov (United States)

Jeansson, Emil; Olsen, Are; Jutterström, Sara

2017-10-01

The evolution of the different types of Arctic Intermediate Water (AIW) in the Nordic Seas is evaluated and compared utilising hydro-chemical data from 1991 to 2009. It has been suggested that these waters are important components of the Norwegian Sea Arctic Intermediate Water (NSAIW), and of the dense overflows to the North Atlantic. Thus, it is important to understand how their properties and distribution vary with time. The AIWs from the Greenland and Iceland Seas, show different degrees of variability during the studied period; however, only the Greenland Sea Arctic Intermediate Water (GSAIW) shows an increasing temperature and salinity throughout the 2000s, which considerably changed the properties of this water mass. Optimum multiparameter (OMP) analysis was conducted to assess the sources of the NSAIW. The analysis shows that the Iceland Sea Arctic Intermediate Water (ISAIW) and the GSAIW both contribute to NSAIW, at different densities corresponding to their respective density range. This illustrates that they flow largely isopycnally from their source regions to the Norwegian Sea. The main source of the NSAIW, however, is the upper Polar Deep Water, which explains the lower concentrations of oxygen and chlorofluorocarbons, and higher salinity and nutrient concentrations of the NSAIW layer compared with the ISAIW and GSAIW. This shows how vital it is to include chemical tracers in any water mass analysis to correctly assess the sources of the water mass being studied.

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.

PolarTREC-Celebrating the Legacy of the IPY Through Researcher-Educator Partnerships

Science.gov (United States)

Timm, K.; Warburton, J.; Larson, A. M.

2009-12-01

Polar TREC-Teachers and Researchers Exploring and Collaborating, a three-year (2007-2009) NSF-funded program, has matched over 40 teachers with polar researchers working in multiple scientific disciplines for 2-8 week Teacher Research Experiences (TRE) in the Arctic and Antarctica during the IPY. PolarTREC contributes to the legacy of the IPY through the creation and dissemination of polar education resources, prolonged teacher-researcher relationships, and contributions to scholarly knowledge on the impacts of TRE's. Products developed during PolarTREC are helping to sustain the widespread interest and enthusiasm in the polar regions generated during the IPY. During their expeditions, participating teachers brought science and information about profound changes at the poles to school, community, and professional audiences through web-based communications, journals, discussion forums, multimedia, and live events. PolarTREC teachers constructed nearly 100 classroom lesson plans and activities as products of their experiences. Live events from the field attracted over 11,000 participants, primarily K-12 students. Although the field experience is central to the PolarTREC TRE Model, many participants cite the relationship they built with their teacher/researcher as one of the best outcomes. Through personal communications, presentations at professional conferences, and continued support of each other’s work through classroom visits or joint proposal development, teachers and researchers have maintained the mutually beneficial relationships established during the IPY. Participating scientists gained access to professional educators with expertise in translating research approaches and results into programs. The need for researchers to explain their research and “boil it down to the raw essence” helped many see how their work fits into a bigger picture, often helping them communicate outside their scientific discipline and to diverse public audiences. Teachers, on

Research Activity and Infrastructure of Korea Polar Research Institute: Current and Future Perspectives

Science.gov (United States)

Jin, D.; Kim, S.; Lee, H.

2011-12-01

The Korea Polar Research Institute (KOPRI) opened the Antarctic King Sejong research station in 1988 at the King George Island off the Antarctic Peninsula and started the polar research mainly in the fields of biology and geology with some atmosphere observations. To extend the view of polar research, the KOPRI opened the Arctic Dasan research station at Ny-Alesund, Spitsbergen Island in 2002 and has studied the rapid climate change diagnostics and some microbiological observation. The KOPRI is now expanding the Arctic research into Alaska and Canada under the international collaboration, and planning to outreach to Russia to monitor the change in permafrost and to understand its impact on global warming. To deepen the views of polar research including the ice covered oceans in both poles, the ice-breaking vessel, the ARAON of about 7000 ton, was launched recently and successfully finished the Arctic and Antarctic cruises for research activity on all perspectives of ocean sciences and support for the King Sejong station. The KOPRI is now building another Antarctic research station, called Jangbogo, at the Terra Nova Bay off the Ross Sea and plan to open the station at the March of 2014. By building the second Antarctic station together with the ARAON, the KOPRI will focus its research on understanding the rapid climate change in west Antarctica such as to monitor the calving of the Larsen Ice shelf, rapid melting of Pine Island Glacier, and upper atmosphere, to study the sea ice and ecosystem change in the Amundsen Sea and the role of the southern annular mode in the west Antarctic warming, upper atmosphere and climate change, to reconstruct paleoclimate records from ice and sediment cores.

Sea-ice indicators of polar bear habitat

Science.gov (United States)

Stern, Harry L.; Laidre, Kristin L.

2016-09-01

Nineteen subpopulations of polar bears (Ursus maritimus) are found throughout the circumpolar Arctic, and in all regions they depend on sea ice as a platform for traveling, hunting, and breeding. Therefore polar bear phenology - the cycle of biological events - is linked to the timing of sea-ice retreat in spring and advance in fall. We analyzed the dates of sea-ice retreat and advance in all 19 polar bear subpopulation regions from 1979 to 2014, using daily sea-ice concentration data from satellite passive microwave instruments. We define the dates of sea-ice retreat and advance in a region as the dates when the area of sea ice drops below a certain threshold (retreat) on its way to the summer minimum or rises above the threshold (advance) on its way to the winter maximum. The threshold is chosen to be halfway between the historical (1979-2014) mean September and mean March sea-ice areas. In all 19 regions there is a trend toward earlier sea-ice retreat and later sea-ice advance. Trends generally range from -3 to -9 days decade-1 in spring and from +3 to +9 days decade-1 in fall, with larger trends in the Barents Sea and central Arctic Basin. The trends are not sensitive to the threshold. We also calculated the number of days per year that the sea-ice area exceeded the threshold (termed ice-covered days) and the average sea-ice concentration from 1 June through 31 October. The number of ice-covered days is declining in all regions at the rate of -7 to -19 days decade-1, with larger trends in the Barents Sea and central Arctic Basin. The June-October sea-ice concentration is declining in all regions at rates ranging from -1 to -9 percent decade-1. These sea-ice metrics (or indicators of habitat change) were designed to be useful for management agencies and for comparative purposes among subpopulations. We recommend that the National Climate Assessment include the timing of sea-ice retreat and advance in future reports.

Arctic circulation regimes.

Science.gov (United States)

Proshutinsky, Andrey; Dukhovskoy, Dmitry; Timmermans, Mary-Louise; Krishfield, Richard; Bamber, Jonathan L

2015-10-13

Between 1948 and 1996, mean annual environmental parameters in the Arctic experienced a well-pronounced decadal variability with two basic circulation patterns: cyclonic and anticyclonic alternating at 5 to 7 year intervals. During cyclonic regimes, low sea-level atmospheric pressure (SLP) dominated over the Arctic Ocean driving sea ice and the upper ocean counterclockwise; the Arctic atmosphere was relatively warm and humid, and freshwater flux from the Arctic Ocean towards the subarctic seas was intensified. By contrast, during anticylonic circulation regimes, high SLP dominated driving sea ice and the upper ocean clockwise. Meanwhile, the atmosphere was cold and dry and the freshwater flux from the Arctic to the subarctic seas was reduced. Since 1997, however, the Arctic system has been under the influence of an anticyclonic circulation regime (17 years) with a set of environmental parameters that are atypical for this regime. We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from the Arctic Ocean and Greenland impact environmental conditions and interrupt their decadal variability. © 2015 The Authors.

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...... and influence policies relating to the Arctic. But each country’s approach is quite different, writes Aki Tonami....

Building on the International Polar Year: Discovering Interdisciplinary Data Through Federated Search

Directory of Open Access Journals (Sweden)

L Yarmey

2014-10-01

Full Text Available The legacy of the International Polar Year 2007–2008 (IPY includes advances in open data and meaningful progress towards interoperability of data, systems, and standards. Enabled by metadata brokering technologies and by the growing adoption of international metadata standards, federated data search welcomes diversity in Arctic data and recognizes the value of expertise in community data repositories. Federated search enables specialized data holdings to be discovered by broader audiences and complements the role of metadata registries such as the Global Change Master Directory, providing interoperability across the Arctic web-of-repositories.

Fifteenth Arctic and Marine Oilspill Program technical seminar

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

At a seminar focusing on Arctic and marine oil spills, papers were presented on the behavior and fate of spilled oil, assessment of oil spill damage and risk, spill response initiatives, research and experimentation in oil spills, spill contingency planning, remote sensing, oil spill countermeasures, in-situ burning, bioremediation, biological effects of spills, and shoreline cleanup. Separate abstracts have been prepared for 57 papers from this seminar.

A distributed atmosphere-sea ice-ocean observatory in the central Arctic Ocean: concept and first results

Science.gov (United States)

Hoppmann, Mario; Nicolaus, Marcel; Rabe, Benjamin; Wenzhöfer, Frank; Katlein, Christian; Scholz, Daniel; Valcic, Lovro

2017-04-01

To understand the current evolution of the Arctic Ocean towards a less extensive, thinner and younger sea ice cover is one of the biggest challenges in climate research. Especially the lack of simultaneous in-situ observations of sea ice, ocean and atmospheric properties leads to significant knowledge gaps in their complex interactions, and how the associated processes impact the polar marine ecosystem. Here we present a concept for the implementation of a long-term strategy to monitor the most essential climate- and ecosystem parameters in the central Arctic Ocean, year round and synchronously. The basis of this strategy is the development and enhancement of a number of innovative autonomous observational platforms, such as rugged weather stations, ice mass balance buoys, ice-tethered bio-optical buoys and upper ocean profilers. The deployment of those complementing platforms in a distributed network enables the simultaneous collection of physical and biogeochemical in-situ data on basin scales and year round, including the largely undersampled winter periods. A key advantage over other observatory systems is that the data is sent via satellite in near-real time, contributing to numerical weather predictions through the Global Telecommunication System (GTS) and to the International Arctic Buoy Programme (IABP). The first instruments were installed on ice floes in the Eurasian Basin in spring 2015 and 2016, yielding exceptional records of essential climate- and ecosystem-relevant parameters in one of the most inaccessible regions of this planet. Over the next 4 years, and including the observational periods of the Year of Polar Prediction (YOPP, 2017-2019) and the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC, 2020), the distributed observatory will be maintained by deployment of additional instruments in the central Arctic each year, benefitting from international logistical efforts.

Future scientific drilling in the Arctic Ocean: Key objectives, areas, and strategies

Science.gov (United States)

Stein, R.; Coakley, B.; Mikkelsen, N.; O'Regan, M.; Ruppel, C.

2012-04-01

Past, Present and Future Changes in Arctic Terrestrial and Marine Systems" (Kananaskis, Alberta/Canada, February 2012). During these workshops, key areas and key scientific themes as well as drilling and site-survey strategies were discussed. Major scientific themes for future Arctic drilling will include: - The Arctic Ocean during the transition from greenhouse to icehouse conditions and millennial scale climate changes; - Physical and chemical changes of the evolving Polar Ocean and Arctic gateways; - Impact of Pleistocene/Holocene warming and sea-level rise on upper continental slope and shelf gas hydrates and on shelf permafrost; - Land-ocean interactions; - Tectonic evolution and birth of the Arctic Ocean basin: Arctic ridges, sea floor spreading and global lithosphere processes. When thinking about future Arctic drilling, it should be clearly emphasized that for the precise planning of future Arctic Ocean drilling campaigns, including site selection, evaluation of proposed drill sites for safety and environmental protection, etc., comprehensive site survey data are needed first. This means that the development of a detailed site survey strategy is a major challenge for the coming years. Here, an overview of perspectives and plans for future Arctic Ocean drilling will be presented.

Genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears

OpenAIRE

Cahill, James A; Stirling, Ian; Kistler, Logan; Salamzade, Rauf; Ersmark, Erik; Fulton, Tara L; Stiller, Mathias; Green, Richard E; Shapiro, Beth

2015-01-01

© 2014 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd. Polar bears are an arctic, marine adapted species that is closely related to brown bears. Genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. However, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the Admiralty, Baranof and Chichagof islands (ABC islands) of Alaska. Here, we...

Analysis of ozone and nitric acid in spring and summer Arctic pollution using aircraft, ground-based, satellite observations and MOZART-4 model: source attribution and partitioning

Directory of Open Access Journals (Sweden)

C. Wespes

2012-01-01

Full Text Available In this paper, we analyze tropospheric O₃ together with HNO₃ during the POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport program, combining observations and model results. Aircraft observations from the NASA ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites and NOAA ARCPAC (Aerosol, Radiation and Cloud Processes affecting Arctic Climate campaigns during spring and summer of 2008 are used together with the Model for Ozone and Related Chemical Tracers, version 4 (MOZART-4 to assist in the interpretation of the observations in terms of the source attribution and transport of O₃ and HNO₃ into the Arctic (north of 60° N. The MOZART-4 simulations reproduce the aircraft observations generally well (within 15%, but some discrepancies in the model are identified and discussed. The observed correlation of O₃ with HNO₃ is exploited to evaluate the MOZART-4 model performance for different air mass types (fresh plumes, free troposphere and stratospheric-contaminated air masses.

Based on model simulations of O₃ and HNO₃ tagged by source type and region, we find that the anthropogenic pollution from the Northern Hemisphere is the dominant source of O₃ and HNO₃ in the Arctic at pressures greater than 400 hPa, and that the stratospheric influence is the principal contribution at pressures less 400 hPa. During the summer, intense Russian fire emissions contribute some amount to the tropospheric columns of both gases over the American sector of the Arctic. North American fire emissions (California and Canada also show an important impact on tropospheric ozone in the Arctic boundary layer.

Additional analysis of tropospheric O₃ measurements from ground-based FTIR and from the IASI satellite sounder made

PolarTREC-Teachers and Researchers Exploring and Collaborating: Science Education from the Poles to the World

Science.gov (United States)

Timm, K. M.; Warburton, J.; Owens, R.; Warnick, W. K.

2008-12-01

PolarTREC--Teachers and Researchers Exploring and Collaborating, a program of the Arctic Research Consortium of the U.S. (ARCUS), is a National Science Foundation (NSF)--funded International Polar Year (IPY) project in which K-12 educators participate in hands-on field experiences, working closely with IPY scientists as a pathway to improving science education. PolarTREC has developed a successful internet-based platform for teachers and researchers to interact and share their diverse experiences and expertise by creating interdisciplinary educational tools including online journals and forums, real-time Internet seminars, lesson plans, activities, audio, and other educational resources that address a broad range of scientific topics. These highly relevant, adaptable, and accessible resources are available to educators across the globe and have connected thousands of students and citizens to the excitement of polar science. By fostering the integration of research and education and infusing education with the thrill of discovery, PolarTREC will produce a legacy of long-term teacher-researcher collaborations and increased student knowledge of and interest in the polar regions well beyond the IPY time period. Educator and student feedback from preliminary evaluations has shown that PolarTREC's comprehensive program activities have many positive impacts on educators and their ability to teach science concepts and improve their teaching methods. Additionally, K-12 students polled in interest surveys showed significant changes in key areas including amount of time spent in school exploring research activities, importance of understanding science for future work, importance of understanding the polar regions as a person in today's world, as well as increased self-reported knowledge and interest in Science, Technology, Engineering, and Mathematics content areas. PolarTREC provides a tested approach and a clear route for researcher participation in the education community

Arctic sea ice melt leads to atmospheric new particle formation.

Science.gov (United States)

Dall Osto, M; Beddows, D C S; Tunved, P; Krejci, R; Ström, J; Hansson, H-C; Yoon, Y J; Park, Ki-Tae; Becagli, S; Udisti, R; Onasch, T; O Dowd, C D; Simó, R; Harrison, Roy M

2017-06-12

Atmospheric new particle formation (NPF) and growth significantly influences climate by supplying new seeds for cloud condensation and brightness. Currently, there is a lack of understanding of whether and how marine biota emissions affect aerosol-cloud-climate interactions in the Arctic. Here, the aerosol population was categorised via cluster analysis of aerosol size distributions taken at Mt Zeppelin (Svalbard) during a 11 year record. The daily temporal occurrence of NPF events likely caused by nucleation in the polar marine boundary layer was quantified annually as 18%, with a peak of 51% during summer months. Air mass trajectory analysis and atmospheric nitrogen and sulphur tracers link these frequent nucleation events to biogenic precursors released by open water and melting sea ice regions. The occurrence of such events across a full decade was anti-correlated with sea ice extent. New particles originating from open water and open pack ice increased the cloud condensation nuclei concentration background by at least ca. 20%, supporting a marine biosphere-climate link through sea ice melt and low altitude clouds that may have contributed to accelerate Arctic warming. Our results prompt a better representation of biogenic aerosol sources in Arctic climate models.

Rich Support for Heterogeneous Polar Data in RAMADDA

Science.gov (United States)

McWhirter, J.; Crosby, C. J.; Griffith, P. C.; Khalsa, S.; Lazzara, M. A.; Weber, W. J.

2013-12-01

Difficult to navigate environments, tenuous logistics, strange forms, deeply rooted cultures - these are all experiences shared by Polar scientist in the field as well as the developers of the underlying data management systems back in the office. Among the key data management challenges that Polar investigations present are the heterogeneity and complexity of data that are generated. Polar regions are intensely studied across many science domains through a variety of techniques - satellite and aircraft remote sensing, in-situ observation networks, modeling, sociological investigations, and extensive PI-driven field project data collection. While many data management efforts focus on large homogeneous collections of data targeting specific science domains (e.g., satellite, GPS, modeling), multi-disciplinary efforts that focus on Polar data need to be able to address a wide range of data formats, science domains and user communities. There is growing use of the RAMADDA (Repository for Archiving, Managing and Accessing Diverse Data) system to manage and provide services for Polar data. RAMADDA is a freely available extensible data repository framework that supports a wide range of data types and services to allow the creation, management, discovery and use of data and metadata. The broad range of capabilities provided by RAMADDA and its extensibility makes it well-suited as an archive solution for Polar data. RAMADDA can run in a number of diverse contexts - as a centralized archive, at local institutions, and can even run on an investigator's laptop in the field, providing in-situ metadata and data management services. We are actively developing archives and support for a number of Polar initiatives: - NASA-Arctic Boreal Vulnerability Experiment (ABoVE): ABoVE is a long-term multi-instrument field campaign that will make use of a wide range of data. We have developed an extensive ontology of program, project and site metadata in RAMADDA, in support of the ABo

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

OpenAIRE

Stephen J. Coulson

2015-01-01

Experience from the Antarctic indicates that the establishment of alien species may have significant negative effects on native flora and fauna in polar regions and is considered to be amongst the greatest threats to biodiversity. But, there have been few similar studies from the Arctic. Although the terrestrial invertebrate inventory of the Svalbard Archipelago is amongst the most complete for any region of the Arctic, no consideration has yet been made of alien terrestrial invertebrate spec...

Poles Apart: The “Bipolar” Pteropod Species Limacina helicina Is Genetically Distinct Between the Arctic and Antarctic Oceans

Science.gov (United States)

Bednarsek, Nina; Linse, Katrin; Nelson, R. John; Pakhomov, Evgeny; Seibel, Brad; Steinke, Dirk; Würzberg, Laura

2010-01-01

The shelled pteropod (sea butterfly) Limacina helicina is currently recognised as a species complex comprising two sub-species and at least five “forma”. However, at the species level it is considered to be bipolar, occurring in both the Arctic and Antarctic oceans. Due to its aragonite shell and polar distribution L. helicina is particularly vulnerable to ocean acidification. As a key indicator of the acidification process, and a major component of polar ecosystems, L. helicina has become a focus for acidification research. New observations that taxonomic groups may respond quite differently to acidification prompted us to reassess the taxonomic status of this important species. We found a 33.56% (±0.09) difference in cytochrome c oxidase subunit I (COI) gene sequences between L. helicina collected from the Arctic and Antarctic oceans. This degree of separation is sufficient for ordinal level taxonomic separation in other organisms and provides strong evidence for the Arctic and Antarctic populations of L. helicina differing at least at the species level. Recent research has highlighted substantial physiological differences between the poles for another supposedly bipolar pteropod species, Clione limacina. Given the large genetic divergence between Arctic and Antarctic L. helicina populations shown here, similarly large physiological differences may exist between the poles for the L. helicina species group. Therefore, in addition to indicating that L. helicina is in fact not bipolar, our study demonstrates the need for acidification research to take into account the possibility that the L. helicina species group may not respond in the same way to ocean acidification in Arctic and Antarctic ecosystems. PMID:20360985

Leveling the field: The role of training, safety programs, and knowledge management systems in fostering inclusive field settings

Science.gov (United States)

Starkweather, S.; Crain, R.; Derry, K. R.

2017-12-01

Knowledge is empowering in all settings, but plays an elevated role in empowering under-represented groups in field research. Field research, particularly polar field research, has deep roots in masculinized and colonial traditions, which can lead to high barriers for women and minorities (e.g. Carey et al., 2016). While recruitment of underrepresented groups into polar field research has improved through the efforts of organizations like the Association of Polar Early Career Scientists (APECS), the experiences and successes of these participants is often contingent on the availability of specialized training opportunities or the quality of explicitly documented information about how to survive Arctic conditions or how to establish successful measurement protocols in harsh environments. In Arctic field research, knowledge is often not explicitly documented or conveyed, but learned through "experience" or informally through ad hoc advice. The advancement of field training programs and knowledge management systems suggest two means for unleashing more explicit forms of knowledge about field work. Examples will be presented along with a case for how they level the playing field and improve the experience of field work for all participants.

The PLOT (Paleolimnological Transect) Project in the Russian Arctic

Science.gov (United States)

Gromig, R.; Andreev, A.; Baumer, M.; Bolshiyanov, D.; Fedorov, G.; Frolova, L.; Krastel, S.; Lebas, E.; Ludikova, A.; Melles, M.; Meyer, H.; Nazarova, L.; Pestryakova, L.; Savelieva, L.; Shumilovskikh, L.; Subetto, D.; Wagner, B.; Wennrich, V.

2017-12-01

The joint Russian- German project 'PLOT - Paleolimnological Transec' aims to recover lake sediment sequences along a >6000 km long longitudinal transect across the Eurasian Arctic in order to investigate the Late Quaternary climatic and environmental history. The climate history of the Arctic is of particular interest since it is the region, which is experiencing major impact of the current climate change. The project is funded for three years (2015-2018) by the Russian and German Ministries of Research. Since 2013 extensive fieldwork, including seismic surveys, coring, and hydrological investigations, was carried out at lakes Ladoga (NW Russia, pilot study), Bolshoye Shuchye (Polar Urals), Emanda (Verkhoyansk Range, field campaign planned for August 2017), Levinson-Lessing and Taymyr (Taymyr Peninsula). Fieldwork at lakes Bolshoye Shuchye, Levinson-Lessing and Taymyr was conducted in collaboration with the Russian-Norwegian CHASE (Climate History along the Arctic Seaboard of Eurasia) project. A major objective of the PLOT project was to recover preglacial sediments. A multiproxy approach was applied to the analytical work of all cores, including (bio-)geochemical, sedimentological, geophysical, and biological analyses. First data implies the presence of preglacial sediments in the cores from all lakes so far visited. Age-depth models, based on radiocarbon dating, OSL dating, paleomagnetic measurements, identification of cryptotephra, and varve counting (where applicable), are in progress. Climate variability in the records shall be compared to that recorded at Lake Eĺgygytgyn (NE Russia), which represents the master record for the Siberian Arctic. The outcome of the PLOT project will be a better understanding of the temporal and spatial variability and development of the Arctic climate. Here, we present the major results and first key interpretations of the PLOT project, along with an outlook on the future strategy and foci. First results from lakes Ladoga

Arctic Haze Analysis

Science.gov (United States)

Mei, Linlu; Xue, Yong

2013-04-01

The Arctic atmosphere is perturbed by nature/anthropogenic aerosol sources known as the Arctic haze, was firstly observed in 1956 by J. Murray Mitchell in Alaska (Mitchell, 1956). Pacyna and Shaw (1992) summarized that Arctic haze is a mixture of anthropogenic and natural pollutants from a variety of sources in different geographical areas at altitudes from 2 to 4 or 5 km while the source for layers of polluted air at altitudes below 2.5 km mainly comes from episodic transportation of anthropogenic sources situated closer to the Arctic. Arctic haze of low troposphere was found to be of a very strong seasonal variation characterized by a summer minimum and a winter maximum in Alaskan (Barrie, 1986; Shaw, 1995) and other Arctic region (Xie and Hopke, 1999). An anthropogenic factor dominated by together with metallic species like Pb, Zn, V, As, Sb, In, etc. and nature source such as sea salt factor consisting mainly of Cl, Na, and K (Xie and Hopke, 1999), dust containing Fe, Al and so on (Rahn et al.,1977). Black carbon and soot can also be included during summer time because of the mix of smoke from wildfires. The Arctic air mass is a unique meteorological feature of the troposphere characterized by sub-zero temperatures, little precipitation, stable stratification that prevents strong vertical mixing and low levels of solar radiations (Barrie, 1986), causing less pollutants was scavenged, the major revival pathway for particulates from the atmosphere in Arctic (Shaw, 1981, 1995; Heintzenberg and Larssen, 1983). Due to the special meteorological condition mentioned above, we can conclude that Eurasian is the main contributor of the Arctic pollutants and the strong transport into the Arctic from Eurasia during winter caused by the high pressure of the climatologically persistent Siberian high pressure region (Barrie, 1986). The paper intends to address the atmospheric characteristics of Arctic haze by comparing the clear day and haze day using different dataset

Human-induced Arctic moistening.

Science.gov (United States)

Min, Seung-Ki; Zhang, Xuebin; Zwiers, Francis

2008-04-25

The Arctic and northern subpolar regions are critical for climate change. Ice-albedo feedback amplifies warming in the Arctic, and fluctuations of regional fresh water inflow to the Arctic Ocean modulate the deep ocean circulation and thus exert a strong global influence. By comparing observations to simulations from 22 coupled climate models, we find influence from anthropogenic greenhouse gases and sulfate aerosols in the space-time pattern of precipitation change over high-latitude land areas north of 55 degrees N during the second half of the 20th century. The human-induced Arctic moistening is consistent with observed increases in Arctic river discharge and freshening of Arctic water masses. This result provides new evidence that human activity has contributed to Arctic hydrological change.

Driving Roles of Tropospheric and Stratospheric Thermal Anomalies in Intensification and Persistence of the Arctic Superstorm in 2012

Science.gov (United States)

Tao, Wei; Zhang, Jing; Fu, Yunfei; Zhang, Xiangdong

2017-10-01

Intense synoptic-scale storms have been more frequently observed over the Arctic during recent years. Specifically, a superstorm hit the Arctic Ocean in August 2012 and preceded a new record low Arctic sea ice extent. In this study, the major physical processes responsible for the storm's intensification and persistence are explored through a series of numerical modeling experiments with the Weather Research and Forecasting model. It is found that thermal anomalies in troposphere as well as lower stratosphere jointly lead to the development of this superstorm. Thermal contrast between the unusually warm Siberia and the relatively cold Arctic Ocean results in strong troposphere baroclinicity and upper level jet, which contribute to the storm intensification initially. On the other hand, Tropopause Polar Vortex (TPV) associated with the thermal anomaly in lower stratosphere further intensifies the upper level jet and accordingly contributes to a drastic intensification of the storm. Stacking with the enhanced surface low, TPV intensifies further, which sustains the storm to linger over the Arctic Ocean for an extended period.

From the field to classrooms: Scientists and educators collaborating to develop K-12 lessons on arctic carbon cycling and climate change that align with Next Generation Science Standards, and informal outreach programs that bring authentic data to informal audiences.

Science.gov (United States)

Brinker, R.; Cory, R. M.

2014-12-01

Next Generation Science Standards (NGSS) calls for students across grade levels to understand climate change and its impacts. To achieve this goal, the NSF-sponsored PolarTREC program paired an educator with scientists studying carbon cycling in the Arctic. The data collection and fieldwork performed by the team will form the basis of hands-on science learning in the classroom and will be incorporated into informal outreach sessions in the community. Over a 16-day period, the educator was stationed at Toolik Field Station in the High Arctic. (Toolik is run by the University of Alaska, Fairbanks, Institute of Arctic Biology.) She participated in a project that analyzed the effects of sunlight and microbial content on carbon production in Artic watersheds. Data collected will be used to introduce the following NGSS standards into the middle-school science curriculum: 1) Construct a scientific explanation based on evidence. 2) Develop a model to explain cycling of water. 3) Develop and use a model to describe phenomena. 4) Analyze and interpret data. 5) A change in one system causes and effect in other systems. Lessons can be telescoped to meet the needs of classrooms in higher or lower grades. Through these activities, students will learn strategies to model an aspect of carbon cycling, interpret authentic scientific data collected in the field, and conduct geoscience research on carbon cycling. Community outreach sessions are also an effective method to introduce and discuss the importance of geoscience education. Informal discussions of firsthand experience gained during fieldwork can help communicate to a lay audience the biological, physical, and chemical aspects of the arctic carbon cycle and the impacts of climate change on these features. Outreach methods will also include novel use of online tools to directly connect audiences with scientists in an effective and time-efficient manner.

The Arctic Turn

DEFF Research Database (Denmark)

Rahbek-Clemmensen, Jon

2018-01-01

In October 2006, representatives of the Arctic governments met in Salekhard in northern Siberia for the biennial Arctic Council ministerial meeting to discuss how the council could combat regional climate change, among other issues. While most capitals were represented by their foreign minister......, a few states – Canada, Denmark, and the United States – sent other representatives. There was nothing unusual about the absence of Per Stig Møller, the Danish foreign minister – a Danish foreign minister had only once attended an Arctic Council ministerial meeting (Arctic Council 2016). Møller......’s nonappearance did, however, betray the low status that Arctic affairs had in the halls of government in Copenhagen. Since the end of the Cold War, where Greenland had helped tie Denmark and the US closer together due to its geostrategically important position between North America and the Soviet Union, Arctic...

Methane emissions from a high arctic valley: findings and challenges

DEFF Research Database (Denmark)

Mastepanov, Mikhail; Sigsgaard, Charlotte; Ström, Lena

2008-01-01

Wet tundra ecosystems are well-known to be a significant source of atmospheric methane. With the predicted stronger effect of global climate change on arctic terrestrial ecosystems compared to lower-latitudes, there is a special obligation to study the natural diversity and the range of possible...... feedback effects on global climate that could arise from Arctic tundra ecosystems. One of the prime candidates for such a feedback mechanism is a potential change in the emissions of methane. Long-term datasets on methane emissions from high arctic sites are almost non-existing but badly needed...... for analyses of controls on interannual and seasonal variations in emissions. To help fill this gap we initiated a measurement program in a productive high arctic fen in the Zackenberg valley, NE Greenland. Methane flux measurements have been carried out at the same location since 1997. Compared...

ARCTIC «UPGRADE» OF V. V. PUTIN, PRESIDENT OF THE RUSSIAN FEDERATION

Directory of Open Access Journals (Sweden)

I. S. Zonn

2017-01-01

Full Text Available After establishment of the Soviet power the Arctic for seven decades had been in the focus of attention accomplishing the heroic, repressive, “educational”, economic, political and ideological functions. In 1930-1950 General Secretary of the Central Committee of the Bolshevik Communist Party I.V. Stalin created the first Soviet Arctic shield that included the economic and military strategic power, transport targeted to protection of entirety and security of the Soviet country. The Stalin’s large-scale project of Arctic development was made public in 1931 and was targeted to the enhanced protection of the polar waters by establishing the naval base on the Barents Sea. For implementation of this project the White Sea-Baltic canal was constructed. The Trust “Arktikugol” was established on the Spitsbergen Archipelago to supply coal to the Northern Navy Fleet. The sea expedition over the Northern Sea Route was also organized to prove the possibility of shipping along this route for one navigation season. Upon its successful completion the Chief Department “Sevmorput” was set up here. The epoch of airship construction was opened to explore the Arctic air expanses. Later on there were expeditions to the North Pole, deployment of army on the Chukotka Peninsula, new expeditions to high latitude terrains, construction of high-capacity icebreakers, aerodromes and military bases on the coast of the Arctic Ocean. Unfortunately, in the 1990s in the time of the Soviet Union breakup and perestroika many facilities of the Stalin’s Arctic Shield had been lost and ceased to exist.The early 21st century witnessed the second energetic and goal-oriented breakthrough into the Arctic region and establishment of the second Arctic Shield or bastion based on the key principles of the Soviet Arctic Shield or, in other words, its upgrade in the new conditions of the polycentric world, which is justly connected with the name of Russian President Putin

The Impact of Stratospheric Circulation Extremes on Minimum Arctic Sea Ice Extent

Science.gov (United States)

Smith, K. L.; Polvani, L. M.; Tremblay, B.

2017-12-01

The interannual variability of summertime Arctic sea ice extent (SIE) is anti-correlated with the leading mode of extratropical atmospheric variability in preceding winter, the Arctic Oscillation (AO). Given this relationship and the need for better seasonal predictions of Arctic SIE, we here examine the role of stratospheric circulation extremes and stratosphere-troposphere coupling in linking the AO and Arctic SIE variability. We show that extremes in the stratospheric circulation during the winter season, namely stratospheric sudden warming (SSW) and strong polar vortex (SPV) events, are associated with significant anomalies in sea ice concentration in the Bering Straight and the Sea of Okhotsk in winter, the Barents Sea in spring and along the Eurasian coastline in summer in both observations and a fully-coupled, stratosphere-resolving general circulation model. The accompanying figure shows the composite mean sea ice concentration anomalies from the Whole Atmosphere Community Climate Model (WACCM) for SSWs (N = 126, top row) and SPVs (N = 99, bottom row) for winter (a,d), spring (b,e) and summer (c,f). Consistent with previous work on the AO, we find that SSWs, which are followed by the negative phase of the AO at the surface, result in sea ice growth, whereas SPVs, which are followed by the positive phase of the AO at the surface, result in sea ice loss, although the dynamic and thermodynamic processes driving these sea ice anomalies in the three Arctic regions, noted above, are different. Our analysis suggests that the presence or absence of stratospheric circulation extremes in winter may play a non-trivial role in determining total September Arctic SIE when combined with other factors.

Health effects from long-range transported contaminants in Arctic top predators: An integrated review based on studies of polar bears and relevant model species.

Science.gov (United States)

Sonne, Christian

2010-07-01

The aim of this review is to provide a thorough overview of the health effects from the complexed biomagnified mixture of long-range transported industrial organochlorines (OCs), polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs) and mercury (Hg) on polar bear (Ursus maritimus) health. Multiple scientific studies of polar bears indicate negative relationships between exposure to these contaminants and health parameters; however, these are all of a correlative nature and do not represent true cause-and-effects. Therefore, information from controlled studies of farmed Norwegian Arctic foxes (Vulpes lagopus) and housed East and West Greenland sledge dogs (Canis familiaris) were included as supportive weight of evidence in the clarification of contaminant exposure and health effects in polar bears. The review showed that hormone and vitamin concentrations, liver, kidney and thyroid gland morphology as well as reproductive and immune systems of polar bears are likely to be influenced by contaminant exposure. Furthermore, exclusively based on polar bear contaminant studies, bone density reduction and neurochemical disruption and DNA hypomethylation of the brain stem seemed to occur. The range of tissue concentration, at which these alterations were observed in polar bears, were ca. 1-70,000 ng/g lw for OCs (blood plasma concentrations of some PCB metabolites even higher), ca. 1-1000 ng/g lw for PBDEs and for PFCs and Hg 114-3052 ng/g ww and 0.1-50 microg/g ww, respectively. Similar concentrations were found in farmed foxes and housed sledge dogs while the lack of dose response designs did not allow an estimation of threshold levels for oral exposure and accumulated tissue concentrations. Nor was it possible to pinpoint a specific group of contaminants being more important than others nor analyze their interactions. For East Greenland polar bears the corresponding daily SigmaOC and SigmaPBDE oral exposure was estimated to be 35 and 0.34 microg/kg body

Arctic potential - Could more structured view improve the understanding of Arctic business opportunities?

Science.gov (United States)

Hintsala, Henna; Niemelä, Sami; Tervonen, Pekka

2016-09-01

The increasing interest towards the Arctic has been witnessed during the past decades. However, the commonly shared definitions of the Arctic key concepts have not yet penetrated national and international arenas for political and economic decision making. The lack of jointly defined framework has made different analyses related to the Arctic quite limited considering the magnitude of economic potential embedded in Arctic. This paper is built on the key findings of two separate, yet connected projects carried out in the Oulu region, Finland. In this paper's approach, the Arctic context has been defined as a composition of three overlapping layers. The first layer is the phenomenological approach to define the Arctic region. The second layer is the strategy-level analysis to define different Arctic paths as well as a national level description of a roadmap to Arctic specialization. The third layer is the operationalization of the first two layers to define the Arctic business context and business opportunities. The studied case from Oulu region indicates that alternative futures for the Arctic competences and business activities are in resemblance with only two of the four identified strategic pathways. Introduction of other pathways to regional level actors as credible and attractive options would require additional, systematic efforts.

Squaring the Arctic Circle: connecting Arctic knowledge with societal needs

Science.gov (United States)

Wilkinson, J.

2017-12-01

Over the coming years the landscape of the Arctic will change substantially- environmentally, politically, and economically. Furthermore, Arctic change has the potential to significantly impact Arctic and non-Arctic countries alike. Thus, our science is in-demand by local communities, politicians, industry leaders and the public. During these times of transition it is essential that the links between science and society be strengthened further. Strong links between science and society is exactly what is needed for the development of better decision-making tools to support sustainable development, enable adaptation to climate change, provide the information necessary for improved management of assets and operations in the Arctic region, and and to inform scientific, economic, environmental and societal policies. By doing so tangible benefits will flow to Arctic societies, as well as for non-Arctic countries that will be significantly affected by climate change. Past experience has shown that the engagement with a broad range of stakeholders is not always an easy process. Consequently, we need to improve collaborative opportunities between scientists, indigenous/local communities, private sector, policy makers, NGOs, and other relevant stakeholders. The development of best practices in this area must build on the collective experiences of successful cross-sectorial programmes. Within this session we present some of the outreach work we have performed within the EU programme ICE-ARC, from community meetings in NW Greenland through to sessions at the United Nations Framework Convention on Climate Change COP Conferences, industry round tables, and an Arctic side event at the World Economic Forum in Davos.

Periodic analysis of solar activity and its link with the Arctic oscillation phenomenon

Energy Technology Data Exchange (ETDEWEB)

Qu, Weizheng; Li, Chun; Du, Ling; Huang, Fei [Ocean University of China, 14-1' -601, 2117 Jinshui Road, Qingdao 266100 (China); Li, Yanfang, E-mail: quweizhe@ouc.edu.cn [Yantai Institute of Coastal Zone Research Chinese Academy of Sciences (China)

2014-12-01

Based on spectrum analysis, we provide the arithmetic expressions of the quasi 11 yr cycle, 110 yr century cycle of relative sunspot numbers, and quasi 22 yr cycle of solar magnetic field polarity. Based on a comparative analysis of the monthly average geopotential height, geopotential height anomaly, and temperature anomaly of the northern hemisphere at locations with an air pressure of 500 HPa during the positive and negative phases of AO (Arctic Oscillation), one can see that the abnormal warming period in the Arctic region corresponds to the negative phase of AO, while the anomalous cold period corresponds to its positive phase. This shows that the abnormal change in the Arctic region is an important factor in determining the anomalies of AO. In accordance with the analysis performed using the successive filtering method, one can see that the AO phenomenon occurring in January shows a clear quasi 88 yr century cycle and quasi 22 yr decadal cycle, which are closely related to solar activities. The results of our comparative analysis show that there is a close inverse relationship between the solar activities (especially the solar magnetic field index changes) and the changes in the 22 yr cycle of the AO occurring in January, and that the two trends are basically opposite of each other. That is to say, in most cases after the solar magnetic index MI rises from the lowest value, the solar magnetic field turns from north to south, and the high-energy particle flow entering the Earth's magnetosphere increases to heat the polar atmosphere, thus causing the AO to drop from the highest value; after the solar magnetic index MI drops from the highest value, the solar magnetic field turns from south to north, and the solar high-energy particle flow passes through the top of the Earth's magnetosphere rather than entering it to heat the polar atmosphere. Thus the polar temperature drops, causing the AO to rise from the lowest value. In summary, the variance

Lidar measurements of ozone and aerosol distributions during the 1992 airborne Arctic stratospheric expedition

Science.gov (United States)

Browell, Edward V.; Butler, Carolyn F.; Fenn, Marta A.; Grant, William B.; Ismail, Syed; Carter, Arlen F.

1994-01-01

The NASA Langley airborne differential absorption lidar system was operated from the NASA Ames DC-8 aircraft during the 1992 Airborne Arctic Stratospheric Expedition to investigate the distribution of stratospheric aerosols and ozone (O3) across the Arctic vortex from January to March 1992. Aerosols from the Mt. Pinatubo eruption were found outside and inside the Arctic vortex with distinctly different scattering characteristics and spatial distributions in the two regions. The aerosol and O3 distributions clearly identified the edge of the vortex and provided additional information on vortex dynamics and transport processes. Few polar stratospheric clouds were observed during the AASE-2; however, those that were found had enhanced scattering and depolarization over the background Pinatubo aerosols. The distribution of aerosols inside the vortex exhibited relatively minor changes during the AASE-2. Ozone depletion inside the vortex as limited to less than or equal to 20 percent in the altitude region from 15-20 km.

Exceptional Air Mass Transport and Dynamical Drivers of an Extreme Wintertime Arctic Warm Event

Science.gov (United States)

Binder, Hanin; Boettcher, Maxi; Grams, Christian M.; Joos, Hanna; Pfahl, Stephan; Wernli, Heini

2017-12-01

At the turn of the years 2015/2016, maximum surface temperature in the Arctic reached record-high values, exceeding the melting point, which led to a strong reduction of the Arctic sea ice extent in the middle of the cold season. Here we show, using a Lagrangian method, that a combination of very different airstreams contributed to this event: (i) warm low-level air of subtropical origin, (ii) initially cold low-level air of polar origin heated by surface fluxes, and (iii) strongly descending air heated by adiabatic compression. The poleward transport of these warm airstreams occurred along an intense low-level jet between a series of cyclones and a quasi-stationary anticyclone. The complex 3-D configuration that enabled this transport was facilitated by continuous warm conveyor belt ascent into the upper part of the anticyclone. This study emphasizes the combined role of multiple transport processes and transient synoptic-scale dynamics for establishing an extreme Arctic warm event.

Arctic sea ice albedo from AVHRR

Science.gov (United States)

Lindsay, R. W.; Rothrock, D. A.

1994-01-01

The seasonal cycle of surface albedo of sea ice in the Arctic is estimated from measurements made with the Advanced Very High Resolution Radiometer (AVHRR) on the polar-orbiting satellites NOAA-10 and NOAA-11. The albedos of 145 200-km-square cells are analyzed. The cells are from March through September 1989 and include only those for which the sun is more than 10 deg above the horizon. Cloud masking is performed manually. Corrections are applied for instrument calibration, nonisotropic reflection, atmospheric interference, narrowband to broadband conversion, and normalization to a common solar zenith angle. The estimated albedos are relative, with the instrument gain set to give an albedo of 0.80 for ice floes in March and April. The mean values for the cloud-free portions of individual cells range from 0.18 to 0.91. Monthly averages of cells in the central Arctic range from 0.76 in April to 0.47 in August. The monthly averages of the within-cell standard deviations in the central Arctic are 0.04 in April and 0.06 in September. The surface albedo and surface temperature are correlated most strongly in March (R = -0.77) with little correlation in the summer. The monthly average lead fraction is determined from the mean potential open water, a scaled representation of the temperature or albedo between 0.0 (for ice) and 1.0 (for water); in the central Arctic it rises from an average 0.025 in the spring to 0.06 in September. Sparse data on aerosols, ozone, and water vapor in the atmospheric column contribute uncertainties to instantaneous, area-average albedos of 0.13, 0.04, and 0.08. Uncertainties in monthly average albedos are not this large. Contemporaneous estimation of these variables could reduce the uncertainty in the estimated albedo considerably. The poor calibration of AVHRR channels 1 and 2 is another large impediment to making accurate albedo estimates.

The ethological approach as a new way of investigating behavioural health in the Arctic.

Science.gov (United States)

Tafforin, Carole

2011-04-01

From an interdisciplinary perspective, the goal of our research in human ethology is to investigate the adaptive dynamics of small groups in isolation and confinement with a particular emphasis on unexplored environments, from circumpolar missions on earth to interplanetary missions in space. The ethological observations were designed to monitor the polar teams on the Subantarctic islands, the Antarctic continent and the Arctic Ocean. The working hypothesis viewed the periodic changes in the groups' organization as optimal behavioural strategies in extreme living and working conditions. The general methodological feature is a quantitative description of observable events based on the motor activity of individuals, interactions and communications among individuals and spatial mapping in collective areas. We observed group organization, group disorganization and group reorganization over extended time periods in the polar stations. Cultural grouping and gender-based individualities were observed as well. Focusing on the Tara Expedition in the Arctic, we observed variations in spatial indicators, including inter-individual positions, and in temporal indicators, like collective times, as behavioural strategies for preventing the monotony of social life. The ethological approach, using non-invasive techniques of observation, description and quantification of spontaneous human behaviour, offers an innovative and complementary tool for sociocultural approaches, enhancing the knowledge of contemporary circumpolar micro-societies. With the changing of environmental context, the Arctic natives would undertake changes in their group organization for maintaining their behavioural health. Such social adaptation could be investigated with this new approach in the field.

Arctic deep-water ferromanganese-oxide deposits reflect the unique characteristics of the Arctic Ocean

Science.gov (United States)

Hein, James; Konstantinova, Natalia; Mikesell, Mariah; Mizell, Kira; Fitzsimmons, Jessica N.; Lam, Phoebe; Jensen, Laramie T.; Xiang, Yang; Gartman, Amy; Cherkashov, Georgy; Hutchinson, Deborah; Till, Claire P.

2017-01-01

Little is known about marine mineral deposits in the Arctic Ocean, an ocean dominated by continental shelf and basins semi-closed to deep-water circulation. Here, we present data for ferromanganese crusts and nodules collected from the Amerasia Arctic Ocean in 2008, 2009, and 2012 (HLY0805, HLY0905, HLY1202). We determined mineral and chemical compositions of the crusts and nodules and the onset of their formation. Water column samples from the GEOTRACES program were analyzed for dissolved and particulate scandium concentrations, an element uniquely enriched in these deposits.The Arctic crusts and nodules are characterized by unique mineral and chemical compositions with atypically high growth rates, detrital contents, Fe/Mn ratios, and low Si/Al ratios, compared to deposits found elsewhere. High detritus reflects erosion of submarine outcrops and North America and Siberia cratons, transport by rivers and glaciers to the sea, and distribution by sea ice, brines, and currents. Uniquely high Fe/Mn ratios are attributed to expansive continental shelves, where diagenetic cycling releases Fe to bottom waters, and density flows transport shelf bottom water to the open Arctic Ocean. Low Mn contents reflect the lack of a mid-water oxygen minimum zone that would act as a reservoir for dissolved Mn. The potential host phases and sources for elements with uniquely high contents are discussed with an emphasis on scandium. Scandium sorption onto Fe oxyhydroxides and Sc-rich detritus account for atypically high scandium contents. The opening of Fram Strait in the Miocene and ventilation of the deep basins initiated Fe-Mn crust growth ∼15 Myr ago.

COLLABORATIVE RESEARCH: TOWARDS ADVANCED UNDERSTANDING AND PREDICTIVE CAPABILITY OF CLIMATE CHANGE IN THE ARCTIC USING A HIGH-RESOLUTION REGIONAL ARCTIC CLIMATE SYSTEM MODEL

Energy Technology Data Exchange (ETDEWEB)

Gutowski, William J.

2013-02-07

The motivation for this project was to advance the science of climate change and prediction in the Arctic region. Its primary goals were to (i) develop a state-of-the-art Regional Arctic Climate system Model (RACM) including high-resolution atmosphere, land, ocean, sea ice and land hydrology components and (ii) to perform extended numerical experiments using high performance computers to minimize uncertainties and fundamentally improve current predictions of climate change in the northern polar regions. These goals were realized first through evaluation studies of climate system components via one-way coupling experiments. Simulations were then used to examine the effects of advancements in climate component systems on their representation of main physics, time-mean fields and to understand variability signals at scales over many years. As such this research directly addressed some of the major science objectives of the BER Climate Change Research Division (CCRD) regarding the advancement of long-term climate prediction.

Temperature-induced recruitment pulses of Arctic dwarf shrub communities

Czech Academy of Sciences Publication Activity Database

Büntgen, Ulf; Hellmann, L.; Tegel, W.; Normand, S.; Myers-Smith, I.; Kirdyanov, A. V.; Nievergelt, D.; Schweingruber, F. H.

2015-01-01

Roč. 103, č. 2 (2015), s. 489-501 ISSN 0022-0477 R&D Projects: GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : recent climate-change * tree-line * environmental-change * forest limit * northern siberia * pinus-sylvestris * kola-peninsula * carbon-cycle * picea-abies * polar urals * Arctic tundra * cambial activity * climate change * dendroecology * dwarf shrubs * East Greenland * plant longevity * plant population and community dynamics * vegetation dynamics * wood anatomy Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 6.180, year: 2015

Attribution of polar warming to human influence

OpenAIRE

Gillett, NP; Stone, DA; Stott, PA; Nozawa, T; Karpechko, AY; Hegerl, GC; Wehner, MF; Jones, PD

2008-01-01

The polar regions have long been expected to warm strongly as a result of anthropogenic climate change, because of the positive feedbacks associated with melting ice and snow. Several studies have noted a rise in Arctic temperatures over recent decades, but have not formally attributed the changes to human influence, owing to sparse observations and large natural variability. Both warming and cooling trends have been observed in Antarctica, which the Intergovernmental Panel on Climate Change ...

The Arctic Observing Viewer: A Web-mapping Application for U.S. Arctic Observing Activities

Science.gov (United States)

Cody, R. P.; Manley, W. F.; Gaylord, A. G.; Kassin, A.; Villarreal, S.; Barba, M.; Dover, M.; Escarzaga, S. M.; Habermann, T.; Kozimor, J.; Score, R.; Tweedie, C. E.

2015-12-01

Although a great deal of progress has been made with various arctic observing efforts, it can be difficult to assess such progress when so many agencies, organizations, research groups and others are making such rapid progress over such a large expanse of the Arctic. To help meet the strategic needs of the U.S. SEARCH-AON program and facilitate the development of SAON and other related initiatives, the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org) has been developed. This web mapping application compiles detailed information pertaining to U.S. Arctic Observing efforts. Contributing partners include the U.S. NSF, USGS, ACADIS, ADIwg, AOOS, a2dc, AON, ARMAP, BAID, IASOA, INTERACT, and others. Over 7700 observation sites are currently in the AOV database and the application allows users to visualize, navigate, select, advance search, draw, print, and more. During 2015, the web mapping application has been enhanced by the addition of a query builder that allows users to create rich and complex queries. AOV is founded on principles of software and data interoperability and includes an emerging "Project" metadata standard, which uses ISO 19115-1 and compatible web services. Substantial efforts have focused on maintaining and centralizing all database information. In order to keep up with emerging technologies, the AOV data set has been structured and centralized within a relational database and the application front-end has been ported to HTML5 to enable mobile access. Other application enhancements include an embedded Apache Solr search platform which provides users with the capability to perform advance searches and an administration web based data management system that allows administrators to add, update, and delete information in real time. We encourage all collaborators to use AOV tools and services for their own purposes and to help us extend the impact of our efforts and ensure AOV complements other cyber-resources. Reinforcing dispersed but

The Experience of Barometric Drifter Application for Investigating the World Ocean Arctic Region

Directory of Open Access Journals (Sweden)

S.V. Motyzhev

2016-08-01

Full Text Available Efficiency of the problem solution to create a regionally-oriented data computing system for marine dynamics and ecosystem evolution modeling and forecasting (that should be capable for providing reliable information for managerial decision making, justifying future economic projects and adjusting the existing ones depends on development level of observational systems, environmental evolution, mathematical models and techniques for observational data assimilation. The analysis of the system as an observational segment of modern geo-informational technology allows us to draw a conclusion that the system of drifter observations is one of the most effective ones nowadays. Surface drifter network, continuously operating in the World Ocean, provides systematic operational data on the surface water circulation, thermal processes in the upper ocean and air pressure. Drifter data, acquired over the past 15 years, allowed one to improve and even change the existing concepts of patterns and mechanisms of regional climatic trend and hydrometeorological anomaly formation under effect of global processes in the Ocean – Atmosphere model (in the high latitudes as well. In the present paper the principle results of the analysis of expediency and feasibility of drifting systematic operative pressure field monitoring establishment in the near-surface atmosphere layer over the Arctic Ocean and the seas of the Russian Federation Arctic Zone have been considered. More than 30 drifters of BTC60/GPS/ice type, whose summarized lifetime as for June 2015 exceeded 6500 days, were deployed in the Arctic in 2012–2015. According to data acquired from the drifters, more than 155 000 air pressure readings were received. The most intensive drifter observations were carried out in two regions: in the Beaufort Sea – Canada Basin and in the Central Arctic. The results of experiments revealed that hardware-software solutions implemented in polar modifications of barometric

Approaching a Postcolonial Arctic

DEFF Research Database (Denmark)

Jensen, Lars

2016-01-01

This article explores different postcolonially configured approaches to the Arctic. It begins by considering the Arctic as a region, an entity, and how the customary political science informed approaches are delimited by their focus on understanding the Arctic as a region at the service...... of the contemporary neoliberal order. It moves on to explore how different parts of the Arctic are inscribed in a number of sub-Arctic nation-state binds, focusing mainly on Canada and Denmark. The article argues that the postcolonial can be understood as a prism or a methodology that asks pivotal questions to all...... approaches to the Arctic. Yet the postcolonial itself is characterised by limitations, not least in this context its lack of interest in the Arctic, and its bias towards conventional forms of representation in art. The article points to the need to develop a more integrated critique of colonial and neo...

The effect of sea ice loss on sea salt aerosol concentrations and the radiative balance in the Arctic

Directory of Open Access Journals (Sweden)

H. Struthers

2011-04-01

Full Text Available Understanding Arctic climate change requires knowledge of both the external and the local drivers of Arctic climate as well as local feedbacks within the system. An Arctic feedback mechanism relating changes in sea ice extent to an alteration of the emission of sea salt aerosol and the consequent change in radiative balance is examined. A set of idealized climate model simulations were performed to quantify the radiative effects of changes in sea salt aerosol emissions induced by prescribed changes in sea ice extent. The model was forced using sea ice concentrations consistent with present day conditions and projections of sea ice extent for 2100. Sea salt aerosol emissions increase in response to a decrease in sea ice, the model results showing an annual average increase in number emission over the polar cap (70–90° N of 86 × 10⁶ m⁻² s⁻¹ (mass emission increase of 23 μg m⁻² s⁻¹. This in turn leads to an increase in the natural aerosol optical depth of approximately 23%. In response to changes in aerosol optical depth, the natural component of the aerosol direct forcing over the Arctic polar cap is estimated to be between −0.2 and −0.4 W m⁻² for the summer months, which results in a negative feedback on the system. The model predicts that the change in first indirect aerosol effect (cloud albedo effect is approximately a factor of ten greater than the change in direct aerosol forcing although this result is highly uncertain due to the crude representation of Arctic clouds and aerosol-cloud interactions in the model. This study shows that both the natural aerosol direct and first indirect effects are strongly dependent on the surface albedo, highlighting the strong coupling between sea ice, aerosols, Arctic clouds and their radiative effects.

Scientific Drilling in the Arctic Ocean: A challenge for the next decades

Science.gov (United States)

Stein, R.; Coakley, B.

2009-04-01

Although major progress in Arctic Ocean research has been made during the last decades, the knowledge of its short- and long-term paleoceanographic and paleoclimatic history as well as its plate-tectonic evolution is much behind that from the other world's oceans. That means - despite the importance of the Arctic in the climate system - the data base we have from this area is still very weak, and large parts of the climate history have not been recovered at all in sedimentary sections. This lack of knowledge is mainly caused by the major technological/ logistic problems in reaching this permanently ice-covered region with normal research vessels and in retrieving long and undisturbed sediment cores. With the successful completion of IODP Expedition 302 ("Arctic Coring Expedition" - ACEX), the first Mission Specific Platform (MSP) expedition within the Integrated Ocean Drilling Program - IODP, a new era in Arctic research has begun. For the first time, a scientific drilling in the permanently ice-covered Arctic Ocean was carried out, penetrating about 430 meters of Quaternary, Neogene, Paleogene and Campanian sediment on the crest of Lomonosov Ridge close to the North Pole. The success of ACEX has certainly opened the door for further scientific drilling in the Arctic Ocean, and will frame the next round of questions to be answered from new drill holes to be taken during the next decades. In order to discuss and plan the future of scientific drilling in the Arctic Ocean, an international workshop was held at the Alfred Wegener Institute (AWI) in Bremerhaven/Germany, (Nov 03-05, 2008; convenors: Bernard Coakley/University of Alaska Fairbanks and Ruediger Stein/AWI Bremerhaven). About 95 scientists from Europe, US, Canada, Russia, Japan, and Korea, and observers from oil companies participated in the workshop. Funding of the workshop was provided by the Consortium for Ocean Leadership (US), the European Science Foundation, the Arctic Ocean Sciences Board, and the

Increasing nest predation will be insufficient to maintain polar bear body condition in the face of sea ice loss.

Science.gov (United States)

Dey, Cody J; Richardson, Evan; McGeachy, David; Iverson, Samuel A; Gilchrist, Hugh G; Semeniuk, Christina A D

2017-05-01

Climate change can influence interspecific interactions by differentially affecting species-specific phenology. In seasonal ice environments, there is evidence that polar bear predation of Arctic bird eggs is increasing because of earlier sea ice breakup, which forces polar bears into nearshore terrestrial environments where Arctic birds are nesting. Because polar bears can consume a large number of nests before becoming satiated, and because they can swim between island colonies, they could have dramatic influences on seabird and sea duck reproductive success. However, it is unclear whether nest foraging can provide an energetic benefit to polar bear populations, especially given the capacity of bird populations to redistribute in response to increasing predation pressure. In this study, we develop a spatially explicit agent-based model of the predator-prey relationship between polar bears and common eiders, a common and culturally important bird species for northern peoples. Our model is composed of two types of agents (polar bear agents and common eider hen agents) whose movements and decision heuristics are based on species-specific bioenergetic and behavioral ecological principles, and are influenced by historical and extrapolated sea ice conditions. Our model reproduces empirical findings that polar bear predation of bird nests is increasing and predicts an accelerating relationship between advancing ice breakup dates and the number of nests depredated. Despite increases in nest predation, our model predicts that polar bear body condition during the ice-free period will continue to decline. Finally, our model predicts that common eider nests will become more dispersed and will move closer to the mainland in response to increasing predation, possibly increasing their exposure to land-based predators and influencing the livelihood of local people that collect eider eggs and down. These results show that predator-prey interactions can have nonlinear responses to

PREFACE: Ocean and climate changes in polar and sub-polar environments: proceedings from the 2010 IODP-Canada/ECORD summer school

Science.gov (United States)

St-Onge, Guillaume; Veiga-Pires, Cristina; Solignac, Sandrine

2011-05-01

IODP logoECORD logo The European Consortium for Ocean Drilling Program (ECORD), the Canadian Consortium for Ocean Drilling (CCOD), the Network of the Universités du Québec (UQ), the Université du Québec à Montréal (UQAM) and GEOTOP sponsored, in 2010, a summer school entitled 'Ocean and climate changes in polar and sub-polar environments'. This summer school took place from 27 June to 12 July in Rimouski, Québec city and Montréal (Quebec, Canada) and was attended by nineteen students and postdoctoral fellows from seven countries: Canada, France, Germany, UK, Serbia, Portugal and the USA. Lectures, hands-on laboratory exercises and laboratory visits were conducted at the Institut des Sciences de la Mer de Rimouski (ISMER), Institut National de la Recherche Scientifique - Centre Eau Terre Environnement (INRS-ETE) and UQAM, in addition to two field trips and a short geological and geophysical cruise on board the R/V Coriolis II in the St Lawrence Estuary and Saguenay Fjord. During the summer school, more than twenty researchers gave lectures on the use of several paleoceanographic and geophysical techniques to reconstruct ocean and climate changes in polar and sub-polar environments. Some of these lectures are presented as short review papers in this volume. They are intended to portray a brief, but state-of-the-art overview of an array of techniques applied to Arctic and sub-Arctic environments, as well as the geological background information needed by the summer school participants to put the scientific expedition and fieldwork into context. The volume begins with a view on the great challenges and key issues to be addressed in the Arctic Ocean (Stein) in the forthcoming years and is followed by a review (O'Regan) on Late Cenozoic paleoceanography of the Central Arctic. The two subsequent papers (St-Onge et al and de Vernal et al) deal with the oceanographic, paleoceanographic and geological context of the Saguenay Fjord, and St Lawrence Estuary and Gulf

The Arctic

International Nuclear Information System (INIS)

Petersen, H.; Meltofte, H.; Rysgaard, S.; Rasch, M.; Jonasson, S.; Christensen, T.R.; Friborg, T.; Soegaard, H.; Pedersen, S.A.

2001-01-01

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

Global change effects on the long-term feeding ecology and contaminant exposures of East Greenland polar bears.

Science.gov (United States)

McKinney, Melissa A; Iverson, Sara J; Fisk, Aaron T; Sonne, Christian; Rigét, Frank F; Letcher, Robert J; Arts, Michael T; Born, Erik W; Rosing-Asvid, Aqqalu; Dietz, Rune

2013-08-01

Rapid climate changes are occurring in the Arctic, with substantial repercussions for arctic ecosystems. It is challenging to assess ecosystem changes in remote polar environments, but one successful approach has entailed monitoring the diets of upper trophic level consumers. Quantitative fatty acid signature analysis (QFASA) and fatty acid carbon isotope (δ(13) C-FA) patterns were used to assess diets of East Greenland (EG) polar bears (Ursus maritimus) (n = 310) over the past three decades. QFASA-generated diet estimates indicated that, on average, EG bears mainly consumed arctic ringed seals (47.5 ± 2.1%), migratory subarctic harp (30.6 ± 1.5%) and hooded (16.7 ± 1.3%) seals and rarely, if ever, consumed bearded seals, narwhals or walruses. Ringed seal consumption declined by 14%/decade over 28 years (90.1 ± 2.5% in 1984 to 33.9 ± 11.1% in 2011). Hooded seal consumption increased by 9.5%/decade (0.0 ± 0.0% in 1984 to 25.9 ± 9.1% in 2011). This increase may include harp seal, since hooded and harp seal FA signatures were not as well differentiated relative to other prey species. Declining δ(13) C-FA ratios supported shifts from more nearshore/benthic/ice-associated prey to more offshore/pelagic/open-water-associated prey, consistent with diet estimates. Increased hooded seal and decreased ringed seal consumption occurred during years when the North Atlantic Oscillation (NAO) was lower. Thus, periods with warmer temperatures and less sea ice were associated with more subarctic and less arctic seal species consumption. These changes in the relative abundance, accessibility, or distribution of arctic and subarctic marine mammals may have health consequences for EG polar bears. For example, the diet change resulted in consistently slower temporal declines in adipose levels of legacy persistent organic pollutants, as the subarctic seals have higher contaminant burdens than arctic seals. Overall, considerable changes are occurring in the EG

The Influence of Sea Ice on Arctic Low Cloud Properties and Radiative Effects

Science.gov (United States)

Taylor, Patrick C.

2015-01-01

The Arctic is one of the most climatically sensitive regions of the Earth. Climate models robustly project the Arctic to warm 2-3 times faster than the global mean surface temperature, termed polar warming amplification (PWA), but also display the widest range of surface temperature projections in this region. The response of the Arctic to increased CO2 modulates the response in tropical and extra-tropical regions through teleconnections in the atmospheric circulation. An increased frequency of extreme precipitation events in the northern mid-latitudes, for example, has been linked to the change in the background equator-to-pole temperature gradient implied by PWA. Understanding the Arctic climate system is therefore important for predicting global climate change. The ice albedo feedback is the primary mechanism driving PWA, however cloud and dynamical feedbacks significantly contribute. These feedback mechanisms, however, do not operate independently. How do clouds respond to variations in sea ice? This critical question is addressed by combining sea ice, cloud, and radiation observations from satellites, including CERES, CloudSAT, CALIPSO, MODIS, and microwave radiometers, to investigate sea ice-cloud interactions at the interannual timescale in the Arctic. Cloud characteristics are strongly tied to the atmospheric dynamic and thermodynamic state. Therefore, the sensitivity of Arctic cloud characteristics, vertical distribution and optical properties, to sea ice anomalies is computed within atmospheric dynamic and thermodynamic regimes. Results indicate that the cloud response to changes in sea ice concentration differs significantly between atmospheric state regimes. This suggests that (1) the atmospheric dynamic and thermodynamic characteristics and (2) the characteristics of the marginal ice zone are important for determining the seasonal forcing by cloud on sea ice variability.

Application of Visible/near Infrared derivative spectroscopy to Arctic paleoceanography

Science.gov (United States)

Ortiz, Joseph D.

2011-05-01

The lack of well-preserved carbonate in much of the Arctic marine environment dictates the need for alternative methods of paleoceanographic reconstruction. The broad variety of physical properties measurements makes them well suited for use in a variety of environments, but they provide unique opportunities when employed in the Arctic. Because Arctic sediment is introduced and reworked by a variety of mechanisms, the signature from multiple processes becomes intermixed with the sediment. Many of these processes operate in other ocean basins, while some function only in Polar Regions. A strategy to address this mixing problem is to employ spectrally-resolved physical properties measurements, or to use multiple methods in conjunction to generate multivariate data sets, which can differentiate concurrent processes. Data of this type is well suited to multivariate analysis techniques such as sample-based or variable-based, varimax-rotated, principle component analysis (VPCA). These are methods that decompose the data matrix to infer process from orthogonal functions. The method is applied to cores from the Chukchi sea to document that visible derivative spectroscopy provides a powerful means of reconstructing sediment provenance. In the Chukchi Sea, diffuse spectral reflectance provides a proxy to monitor variations in Holocene flow through the Bering Strait.

Application of Visible/near Infrared derivative spectroscopy to Arctic paleoceanography

International Nuclear Information System (INIS)

Ortiz, Joseph D

2011-01-01

The lack of well-preserved carbonate in much of the Arctic marine environment dictates the need for alternative methods of paleoceanographic reconstruction. The broad variety of physical properties measurements makes them well suited for use in a variety of environments, but they provide unique opportunities when employed in the Arctic. Because Arctic sediment is introduced and reworked by a variety of mechanisms, the signature from multiple processes becomes intermixed with the sediment. Many of these processes operate in other ocean basins, while some function only in Polar Regions. A strategy to address this mixing problem is to employ spectrally-resolved physical properties measurements, or to use multiple methods in conjunction to generate multivariate data sets, which can differentiate concurrent processes. Data of this type is well suited to multivariate analysis techniques such as sample-based or variable-based, varimax-rotated, principle component analysis (VPCA). These are methods that decompose the data matrix to infer process from orthogonal functions. The method is applied to cores from the Chukchi sea to document that visible derivative spectroscopy provides a powerful means of reconstructing sediment provenance. In the Chukchi Sea, diffuse spectral reflectance provides a proxy to monitor variations in Holocene flow through the Bering Strait.

A new high resolution tidal model in the arctic ocean

DEFF Research Database (Denmark)

Cancet, M.; Andersen, Ole Baltazar; Lyard, F.

The Arctic Ocean is a challenging region for tidal modeling, because of its complex and not well-documented bathymetry, together combined with the intermittent presence of sea ice and the fact that the in situ tidal observations are rather scarce at such high latitudes. As a consequence, the accu......The Arctic Ocean is a challenging region for tidal modeling, because of its complex and not well-documented bathymetry, together combined with the intermittent presence of sea ice and the fact that the in situ tidal observations are rather scarce at such high latitudes. As a consequence......, the accuracy of the global tidal models decreases by several centimeters in the Polar Regions. In particular, it has a large impact on the quality of the satellite altimeter sea surface heights in these regions (ERS1/2, Envisat, CryoSat-2, SARAL/AltiKa and the future Sentinel-3 mission). Better knowledge......-growing maritime and industrial activities in this region. NOVELTIS and DTU Space have developed a regional, high-resolution tidal atlas in the Arctic Ocean, in the framework of the CryoSat Plus for Ocean (CP4O) ESA project. In particular, this atlas benefits from the assimilation of the most complete satellite...

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

Sea-ice indicators of polar bear habitat

Directory of Open Access Journals (Sweden)

H. L. Stern

2016-09-01

Full Text Available Nineteen subpopulations of polar bears (Ursus maritimus are found throughout the circumpolar Arctic, and in all regions they depend on sea ice as a platform for traveling, hunting, and breeding. Therefore polar bear phenology – the cycle of biological events – is linked to the timing of sea-ice retreat in spring and advance in fall. We analyzed the dates of sea-ice retreat and advance in all 19 polar bear subpopulation regions from 1979 to 2014, using daily sea-ice concentration data from satellite passive microwave instruments. We define the dates of sea-ice retreat and advance in a region as the dates when the area of sea ice drops below a certain threshold (retreat on its way to the summer minimum or rises above the threshold (advance on its way to the winter maximum. The threshold is chosen to be halfway between the historical (1979–2014 mean September and mean March sea-ice areas. In all 19 regions there is a trend toward earlier sea-ice retreat and later sea-ice advance. Trends generally range from −3 to −9 days decade−1 in spring and from +3 to +9 days decade−1 in fall, with larger trends in the Barents Sea and central Arctic Basin. The trends are not sensitive to the threshold. We also calculated the number of days per year that the sea-ice area exceeded the threshold (termed ice-covered days and the average sea-ice concentration from 1 June through 31 October. The number of ice-covered days is declining in all regions at the rate of −7 to −19 days decade−1, with larger trends in the Barents Sea and central Arctic Basin. The June–October sea-ice concentration is declining in all regions at rates ranging from −1 to −9 percent decade−1. These sea-ice metrics (or indicators of habitat change were designed to be useful for management agencies and for comparative purposes among subpopulations. We recommend that the National Climate Assessment include the timing of sea-ice retreat and advance in

Three recent ice entrapments of Arctic cetaceans in West Greenland and the eastern Canadian High Arctic

Directory of Open Access Journals (Sweden)

MP Heide-Jørgensen

2002-07-01

Full Text Available Three ice entrapments of Monodontids have been reported in the western North Atlantic since 1993. Hunters in Disko Bay, West Greenland, discovered one in March 1994 that included about 150 narwhals (Monodon monoceros. The entrapment occurred during a sudden cold period which caused ice to form rapidly. The trapped whales were subject to hunting, but about 50 of the killed whales could not be retrieved in the ice. The whales were trapped in a small opening in the ice and because of that they would probably have succumbed even if not discovered by hunters. Two entrapments involving white whales or belugas (Delphinapterus leucas occurred in the eastern Canadian Arctic in May 1999; one in Lancaster Sound discovered by polar bear (Ursus maritimus researchers and one in Jones Sound discovered by hunters. The first included one bowhead whale (Balaena mysticetus and about 40 belugas that were being preyed upon by polar bears. The second involved at least 170 belugas, of which about 100 were killed by polar bears and 17 were taken by hunters. The entrapments in Disko Bay and Jones Sound both occurred in areas where entrapments have previously been reported, whereas the one in Lancaster Sound was in a new area.

PRIMARY PRODUCTIVITY - PHYTOPLANKTON, CHLOROPHYLL A CONCENTRATION, and others in Arctic Ocean from 1959-08-03 to 2011-10-21 (NCEI Accession 0161176)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Arctic Ocean net primary productivity (NPP) was assembled for 1959-2011 from existing databases and recent polar research cruises. At each NPP station, if available,...

Are we approaching an Arctic ozone hole

International Nuclear Information System (INIS)

Braathen, Geir

1999-01-01

Observations during the last decade in the Arctic areas mainly made by satellite, on the ground and by probes and sensors in the stratosphere are presented. Future perspectives are deducted from the results. Factors that may influence the ozone layer negatively are: Emission rate of ozone destroying compounds, the rapidly increasing use of some substitutes, increased concentrations of steam from aeroplanes and increased amount of methane, decreasing temperature in the stratosphere due to increasing amounts of climatic gases, large volcanic eruptions and altered timing for the polar whirl dissolution. It is concluded that the ozone reduction will be larger than observed at present in the next 10 to 20 years

Characteristics of colored dissolved organic matter (CDOM) in the Arctic outflow in Fram Strait: assessing the changes and fate of terrigenous CDOM in the Arctic Ocean

DEFF Research Database (Denmark)

Granskog, M.A.; Stedmon, Colin; Dodd, P.A.

2012-01-01

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...

An assessment of ten ocean reanalyses in the polar regions

Science.gov (United States)

Uotila, Petteri

2017-04-01

Ocean reanalysis (ORA) combines observations either statistically or with a hydrodynamical model, to reconstruct historical changes in the ocean. Global and regional ORA products are increasingly used in polar research, but their quality remains to be systematically assessed. To address this, the Polar ORA Intercomparison Project (PORA-IP) has been established following on from the ORA-IP project (Balmaseda et al. 2015, with other papers in a special issue of Climate Dynamics). The PORA-IP is constituted under the COST EOS initiative with plans to review reanalyses products in both the Arctic and Antarctic, and is endorsed by YOPP - the Year of Polar Prediction project. Currently, the PORA-IP team consists of 21 researchers from 15 institutes and universities. The ORA-IP products with polar physics, such as sea ice, have been updated where necessary and collected in a public database. In addition to model output, available observational polar climatologies are collected and used in the assessments. Due to the extensive variety of products, this database should become a valuable resource outside the PORA-IP community. For a comprehensive evaluation of the ten ORA products (CGLORSv5, ECDA3.1, GECCO2, Glorys2v4, GloSea5_GO5, MOVEG2i, ORAP5, SODA3.3.1, TOPAZ4 and UR025.4) in the Arctic and Southern Oceans several specific diagnostics are assessed. The PORA-IP diagnostics target the following topics: hydrography; heat, salinity and freshwater content; ocean transports and surface currents; mixed layer depth; sea-ice concentration and thickness; and snow thickness over sea ice. Based on these diagnostics, ORA product biases against observed data and their mutual spread are quantified, and possible reasons for discrepancies discussed. So far, we have identified product outliers and evaluated the multi-model mean. We have identified the importance of the atmospheric forcing, air-ocean coupling protocol and sea-ice data assimilation for the product performance. Moreover, we

Lessons learned in managing crowdsourced data in the Alaskan Arctic.

Science.gov (United States)

Mastracci, Diana

2017-04-01

There is perhaps no place in which the consequences of global climate change can be felt more acutely than the Arctic. However, due to lack of measurements at the high latitudes, validation processes are often problematic. Citizen science projects, co-designed together with Native communities at the interface of traditional knowledge and scientific research, could play a major role in climate change adaptation strategies by advancing knowledge of the Arctic system, strengthening inter-generational bonds and facilitating improved knowledge transfer. This presentation will present lessons learned from a pilot project in the Alaskan Arctic, in which innovative approaches were used to design climate change adaptation strategies to support young subsistence hunters in taking in-situ measurements whilst out on the sea-ice. Both the socio-cultural and hardware/software challenges presented in this presentation, could provide useful guidance for future programs that aim to integrate citizens' with scientific data in Arctic communities.

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

Science.gov (United States)

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

2011-12-01

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

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.)

Arctic wind energy

International Nuclear Information System (INIS)

Peltola, E.; Holttinen, H.; Marjaniemi, M.; Tammelin, B.

1998-01-01

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.)

Hygroscopicity and composition of Alaskan Arctic CCN during April 2008

Directory of Open Access Journals (Sweden)

R. H. Moore

2011-11-01

Full Text Available We present a comprehensive characterization of cloud condensation nuclei (CCN sampled in the Alaskan Arctic during the 2008 Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC project, a component of the POLARCAT and International Polar Year (IPY initiatives. Four distinct air mass types were sampled including a cleaner Arctic background and a relatively pristine sea ice boundary layer as well as biomass burning and anthropogenic pollution plumes. Despite differences in chemical composition, inferred aerosol hygroscopicities were fairly invariant and ranged from κ = 0.1–0.3 over the atmospherically-relevant range of water vapor supersaturations studied. Organic aerosols sampled were found to be well-oxygenated, consistent with long-range transport and aerosol aging processes. However, inferred hygroscopicities are less than would be predicted based on previous parameterizations of biogenic oxygenated organic aerosol, suggesting an upper limit on organic aerosol hygroscopicity above which κ is less sensitive to the O:C ratio. Most Arctic aerosols act as CCN above 0.1 % supersaturation, although the data suggest the presence of an externally-mixed, non-CCN-active mode comprising approximately 0–20% of the aerosol number. CCN closure was assessed using measured size distributions, bulk chemical composition, and assumed aerosol mixing states; CCN predictions tended toward overprediction, with the best agreement (±0–20 % obtained by assuming the aerosol to be externally-mixed with soluble organics. Closure also varied with CCN concentration, and the best agreement was found for CCN concentrations above 100 cm⁻³ with a 1.5- to 3-fold overprediction at lower concentrations.

Nuclear genomic sequences reveal that polar bears are an old and distinct bear lineage.

Science.gov (United States)

Hailer, Frank; Kutschera, Verena E; Hallström, Björn M; Klassert, Denise; Fain, Steven R; Leonard, Jennifer A; Arnason, Ulfur; Janke, Axel

2012-04-20

Recent studies have shown that the polar bear matriline (mitochondrial DNA) evolved from a brown bear lineage since the late Pleistocene, potentially indicating rapid speciation and adaption to arctic conditions. Here, we present a high-resolution data set from multiple independent loci across the nuclear genomes of a broad sample of polar, brown, and black bears. Bayesian coalescent analyses place polar bears outside the brown bear clade and date the divergence much earlier, in the middle Pleistocene, about 600 (338 to 934) thousand years ago. This provides more time for polar bear evolution and confirms previous suggestions that polar bears carry introgressed brown bear mitochondrial DNA due to past hybridization. Our results highlight that multilocus genomic analyses are crucial for an accurate understanding of evolutionary history.

ALGORITHMS AND PROGRAMS FOR STRONG GRAVITATIONAL LENSING IN KERR SPACE-TIME INCLUDING POLARIZATION

Energy Technology Data Exchange (ETDEWEB)

Chen, Bin; Maddumage, Prasad [Research Computing Center, Department of Scientific Computing, Florida State University, Tallahassee, FL 32306 (United States); Kantowski, Ronald; Dai, Xinyu; Baron, Eddie, E-mail: bchen3@fsu.edu [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)

2015-05-15

Active galactic nuclei (AGNs) and quasars are important astrophysical objects to understand. Recently, microlensing observations have constrained the size of the quasar X-ray emission region to be of the order of 10 gravitational radii of the central supermassive black hole. For distances within a few gravitational radii, light paths are strongly bent by the strong gravity field of the central black hole. If the central black hole has nonzero angular momentum (spin), then a photon’s polarization plane will be rotated by the gravitational Faraday effect. The observed X-ray flux and polarization will then be influenced significantly by the strong gravity field near the source. Consequently, linear gravitational lensing theory is inadequate for such extreme circumstances. We present simple algorithms computing the strong lensing effects of Kerr black holes, including the effects on polarization. Our algorithms are realized in a program “KERTAP” in two versions: MATLAB and Python. The key ingredients of KERTAP are a graphic user interface, a backward ray-tracing algorithm, a polarization propagator dealing with gravitational Faraday rotation, and algorithms computing observables such as flux magnification and polarization angles. Our algorithms can be easily realized in other programming languages such as FORTRAN, C, and C++. The MATLAB version of KERTAP is parallelized using the MATLAB Parallel Computing Toolbox and the Distributed Computing Server. The Python code was sped up using Cython and supports full implementation of MPI using the “mpi4py” package. As an example, we investigate the inclination angle dependence of the observed polarization and the strong lensing magnification of AGN X-ray emission. We conclude that it is possible to perform complex numerical-relativity related computations using interpreted languages such as MATLAB and Python.

ALGORITHMS AND PROGRAMS FOR STRONG GRAVITATIONAL LENSING IN KERR SPACE-TIME INCLUDING POLARIZATION

International Nuclear Information System (INIS)

Chen, Bin; Maddumage, Prasad; Kantowski, Ronald; Dai, Xinyu; Baron, Eddie

2015-01-01

Active galactic nuclei (AGNs) and quasars are important astrophysical objects to understand. Recently, microlensing observations have constrained the size of the quasar X-ray emission region to be of the order of 10 gravitational radii of the central supermassive black hole. For distances within a few gravitational radii, light paths are strongly bent by the strong gravity field of the central black hole. If the central black hole has nonzero angular momentum (spin), then a photon’s polarization plane will be rotated by the gravitational Faraday effect. The observed X-ray flux and polarization will then be influenced significantly by the strong gravity field near the source. Consequently, linear gravitational lensing theory is inadequate for such extreme circumstances. We present simple algorithms computing the strong lensing effects of Kerr black holes, including the effects on polarization. Our algorithms are realized in a program “KERTAP” in two versions: MATLAB and Python. The key ingredients of KERTAP are a graphic user interface, a backward ray-tracing algorithm, a polarization propagator dealing with gravitational Faraday rotation, and algorithms computing observables such as flux magnification and polarization angles. Our algorithms can be easily realized in other programming languages such as FORTRAN, C, and C++. The MATLAB version of KERTAP is parallelized using the MATLAB Parallel Computing Toolbox and the Distributed Computing Server. The Python code was sped up using Cython and supports full implementation of MPI using the “mpi4py” package. As an example, we investigate the inclination angle dependence of the observed polarization and the strong lensing magnification of AGN X-ray emission. We conclude that it is possible to perform complex numerical-relativity related computations using interpreted languages such as MATLAB and Python

Collaboration across the Arctic

DEFF Research Database (Denmark)

Huppert, Verena Gisela; Chuffart, Romain François R.

2017-01-01

The Arctic is witnessing the rise of a new paradigm caused by an increase in pan-Arctic collaborations which co-exist with the region’s traditional linkages with the South. Using an analysis of concrete examples of regional collaborations in the Arctic today in the fields of education, health...... and infrastructure, this paper questions whether pan-Arctic collaborations in the Arctic are more viable than North-South collaborations, and explores the reasons behind and the foreseeable consequences of such collaborations. It shows that the newly emerging East-West paradigm operates at the same time...... as the traditional North-South paradigm, with no signs of the East-West paradigm being more viable in the foreseeable future. However, pan-Arctic collaboration, both due to pragmatic reasons and an increased awareness of similarities, is likely to increase in the future. The increased regionalization process...

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

Directory of Open Access Journals (Sweden)

J. Lüers

2010-01-01

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

Resilience and risk: a demographic model to inform conservation planning for polar bears

Science.gov (United States)

Regehr, Eric V.; Wilson, Ryan R.; Rode, Karyn D.; Runge, Michael C.

2015-01-01

Climate change is having widespread ecological effects, including loss of Arctic sea ice. This has led to listing of the polar bear (Ursus maritimus) and other ice-dependent marine mammals under the U.S. Endangered Species Act (ESA). Methods are needed to evaluate the effects of climate change on population persistence to inform recovery planning for listed species. For polar bears, this includes understanding interactions between climate and secondary factors, such as subsistence harvest, which provide economic, nutritional, or cultural value to humans.

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.

Brominated flame retardants in the Arctic. An overview of spatial and temporal trends

Energy Technology Data Exchange (ETDEWEB)

Wit, C de [Institute of Applied Environmental Research, Stockholm (Sweden); Alaee, M; Muir, D [National Water Research Institute, Burlington, MA (United States)

2004-09-15

The Stockholm Convention on Persistent Organic Pollutants (POPs), which entered into force on May 17, 2004, includes wording that chemicals with the characteristics of POPs are those found in locations ''distant from sources'' and those for which ''monitoring data showing that long-range environmental transport of the chemical may have occurred''. Thus, the Arctic has become an important indicator region for assessment of persistence and bioaccumulation. The Arctic environment is well suited as a region in which to evaluate POPs. Some regions of thee Arctic, particularly the Barents Sea area north of Norway and western Russia are relatively close to source regions of POPs. Cold conditions favor persistence of POPs relative to temperate or tropical environments. The presence of fourth level carnivores (e.g. polar bears and seabirds), and storage of lipid as an energy source, make Arctic food webs vulnerable to bioaccumulative chemicals. Indigenous people in the Arctic utilizing a traditional diet, which is high in nutritionally beneficial fat, results in their elevated exposure to some POPs. The first indication that brominated flame retardants (BFRs) were reaching the Arctic was the detection by Jansson et al. of lower molecular weight polybrominated diphenyl ethers (PBDEs) in Svalbard Brunnichfs guillemots (130 ng/g lipid weight) and ringed seals (40 ng/g lw) collected in 1981. Whitefish collected from Lake Storvindeln in 1986, a pristine mountain lake in the Swedish mountains near Ammarnas, had {sigma}PBDE levels of 26 ng/g lw. Despite these early findings, only recently have the spatial and temporal trends of BFRs been studied in detail in the Arctic. The purpose of this paper is to review the new data on BFRs in the Arctic and assess whether this information supports the view that PBDEs and other BFRs of similar molecular weight are POPs and potential global pollutants. This review is based on a recent assessment of POPs in the Arctic combined with newer data

Brominated flame retardants in the Arctic. An overview of spatial and temporal trends

Energy Technology Data Exchange (ETDEWEB)

Wit, C. de [Institute of Applied Environmental Research, Stockholm (Sweden); Alaee, M.; Muir, D. [National Water Research Institute, Burlington, MA (United States)

2004-09-15

The Stockholm Convention on Persistent Organic Pollutants (POPs), which entered into force on May 17, 2004, includes wording that chemicals with the characteristics of POPs are those found in locations ''distant from sources'' and those for which ''monitoring data showing that long-range environmental transport of the chemical may have occurred''. Thus, the Arctic has become an important indicator region for assessment of persistence and bioaccumulation. The Arctic environment is well suited as a region in which to evaluate POPs. Some regions of thee Arctic, particularly the Barents Sea area north of Norway and western Russia are relatively close to source regions of POPs. Cold conditions favor persistence of POPs relative to temperate or tropical environments. The presence of fourth level carnivores (e.g. polar bears and seabirds), and storage of lipid as an energy source, make Arctic food webs vulnerable to bioaccumulative chemicals. Indigenous people in the Arctic utilizing a traditional diet, which is high in nutritionally beneficial fat, results in their elevated exposure to some POPs. The first indication that brominated flame retardants (BFRs) were reaching the Arctic was the detection by Jansson et al. of lower molecular weight polybrominated diphenyl ethers (PBDEs) in Svalbard Brunnichfs guillemots (130 ng/g lipid weight) and ringed seals (40 ng/g lw) collected in 1981. Whitefish collected from Lake Storvindeln in 1986, a pristine mountain lake in the Swedish mountains near Ammarnas, had {sigma}PBDE levels of 26 ng/g lw. Despite these early findings, only recently have the spatial and temporal trends of BFRs been studied in detail in the Arctic. The purpose of this paper is to review the new data on BFRs in the Arctic and assess whether this information supports the view that PBDEs and other BFRs of similar molecular weight are POPs and potential global pollutants. This review is based on a recent assessment of POPs

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

Science.gov (United States)

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

2015-01-01

Plastic, as a form of marine litter, is found in varying quantities and sizes around the globe from surface waters to deep-sea sediments. Identifying patterns of microplastic distribution will benefit an understanding of the scale of their potential effect on the environment and organisms. As sea ice extent is reducing in the Arctic, heightened shipping and fishing activity may increase marine pollution in the area. Microplastics may enter the region following ocean transport and local input, although baseline contamination measurements are still required. Here we present the first study of microplastics in Arctic waters, south and southwest of Svalbard, Norway. Microplastics were found in surface (top 16 cm) and sub-surface (6 m depth) samples using two independent techniques. Origins and pathways bringing microplastic to the Arctic remain unclear. Particle composition (95% fibres) suggests they may either result from the breakdown of larger items (transported over large distances by prevailing currents, or derived from local vessel activity), or input in sewage and wastewater from coastal areas. Concurrent observations of high zooplankton abundance suggest a high probability for marine biota to encounter microplastics and a potential for trophic interactions. Further research is required to understand the effects of microplastic-biota interaction within this productive environment. PMID:26446348

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

Science.gov (United States)

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

2015-10-01

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

Spatial and seasonal distribution of Arctic aerosols observed by the CALIOP satellite instrument (2006–2012

Directory of Open Access Journals (Sweden)

M. Di Pierro

2013-07-01

Full Text Available We use retrievals of aerosol extinction from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP onboard the CALIPSO satellite to examine the vertical, horizontal and temporal variability of tropospheric Arctic aerosols during the period 2006–2012. We develop an empirical method that takes into account the difference in sensitivity between daytime and nighttime retrievals over the Arctic. Comparisons of the retrieved aerosol extinction to in situ measurements at Barrow (Alaska and Alert (Canada show that CALIOP reproduces the observed seasonal cycle and magnitude of surface aerosols to within 25 %. In the free troposphere, we find that daytime CALIOP retrievals will only detect the strongest aerosol haze events, as demonstrated by a comparison to aircraft measurements obtained during NASA's ARCTAS mission during April 2008. This leads to a systematic underestimate of the column aerosol optical depth by a factor of 2–10. However, when the CALIOP sensitivity threshold is applied to aircraft observations, we find that CALIOP reproduces in situ observations to within 20% and captures the vertical profile of extinction over the Alaskan Arctic. Comparisons with the ground-based high spectral resolution lidar (HSRL at Eureka, Canada, show that CALIOP and HSRL capture the evolution of the aerosol backscatter vertical distribution from winter to spring, but a quantitative comparison is inconclusive as the retrieved HSRL backscatter appears to overestimate in situ observations by a factor of 2 at all altitudes. In the High Arctic (>70° N near the surface (−1, followed by a sharp decline and a minimum in May–September (1–4 Mm−1, thus providing the first pan-Arctic view of Arctic haze seasonality. The European and Asian Arctic sectors display the highest wintertime extinctions, while the Atlantic sector is the cleanest. Over the Low Arctic (60–70° N near the surface, CALIOP extinctions reach a maximum over land in summer due to

Polarized proton acceleration program at the AGS and RHIC

International Nuclear Information System (INIS)

Lee, Y.Y.

1995-01-01

Presented is an overview of the program for acceleration of polarized protons in the AGS and their injection into the RHIC collider. The problem of depolarizing resonances in strong focusing circulator accelerators is discussed. The intrinsic resonances are jumped over by the fast tune jump, and a partial Siberian Snake is used to compensate for over forty imperfection resonances in the AGS. Two sets of full Siberian Snake and spin rotators will be employed in RHIC

Aerosol indirect effects on the nighttime Arctic Ocean surface from thin, predominantly liquid clouds

Directory of Open Access Journals (Sweden)

L. M. Zamora

2017-06-01

Full Text Available Aerosol indirect effects have potentially large impacts on the Arctic Ocean surface energy budget, but model estimates of regional-scale aerosol indirect effects are highly uncertain and poorly validated by observations. Here we demonstrate a new way to quantitatively estimate aerosol indirect effects on a regional scale from remote sensing observations. In this study, we focus on nighttime, optically thin, predominantly liquid clouds. The method is based on differences in cloud physical and microphysical characteristics in carefully selected clean, average, and aerosol-impacted conditions. The cloud subset of focus covers just ∼ 5 % of cloudy Arctic Ocean regions, warming the Arctic Ocean surface by ∼ 1–1.4 W m−2 regionally during polar night. However, within this cloud subset, aerosol and cloud conditions can be determined with high confidence using CALIPSO and CloudSat data and model output. This cloud subset is generally susceptible to aerosols, with a polar nighttime estimated maximum regionally integrated indirect cooling effect of ∼ −0.11 W m−2 at the Arctic sea ice surface (∼ 8 % of the clean background cloud effect, excluding cloud fraction changes. Aerosol presence is related to reduced precipitation, cloud thickness, and radar reflectivity, and in some cases, an increased likelihood of cloud presence in the liquid phase. These observations are inconsistent with a glaciation indirect effect and are consistent with either a deactivation effect or less-efficient secondary ice formation related to smaller liquid cloud droplets. However, this cloud subset shows large differences in surface and meteorological forcing in shallow and higher-altitude clouds and between sea ice and open-ocean regions. For example, optically thin, predominantly liquid clouds are much more likely to overlay another cloud over the open ocean, which may reduce aerosol indirect effects on the surface. Also, shallow clouds over

Recent results of the STAR high-energy polarized proton-proton program at RHIC at BNL

International Nuclear Information System (INIS)

Surrow, Bernd

2007-01-01

The STAR experiment at the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is carrying out a spin physics program colliding transverse or longitudinal polarized proton beams at √(s) 200 - 500GeV to gain a deeper insight into the spin structure and dynamics of the proton. These studies provide fundamental tests of Quantum Chromodynamics (QCD).One of the main objectives of the STAR spin physics program is the determination of the polarized gluon distribution function through a measurement of the longitudinal double-spin asymmetry, ALL, for various processes. Recent results will be shown on the measurement of ALL for inclusive jet production, neutral pion production and charged pion production at √(s) = 200GeV. In addition to these measurements involving longitudinal polarized proton beams, the STAR collaboration has performed several important measurements employing transverse polarized proton beams. New results on the measurement of the transverse single-spin asymmetry, AN, for forward neutral pion production and the first measurement of AN for mid-rapidity di-jet production will be discussed

Arctic Security

DEFF Research Database (Denmark)

Wang, Nils

2013-01-01

The inclusion of China, India, Japan, Singapore and Italy as permanent observers in the Arctic Council has increased the international status of this forum significantly. This chapter aims to explain the background for the increased international interest in the Arctic region through an analysis...

Proceedings of the 26. Arctic and Marine Oilspill Program (AMOP) Technical Seminar

International Nuclear Information System (INIS)

2003-01-01

The papers presented at this Arctic and Marine Oilspill Program (AMOP) technical seminar reviewed the latest technologies that can be applied to the recovery and mitigation of marine oil spills. The very first seminar was held back in 1976 in response to public concerns regarding the potential for oil spills associated with offshore drilling in the Beaufort Sea in the Canadian Arctic. This twenty-sixth issue includes an appendix listing more than 1,200 AMOP papers from the first 25 years of the conference. Today, the AMOP conference has become international in nature and is the only surviving technical conference on oil spill science and technology in the world. While technical presentations about oil spills are the primary focus of the conference, many presentations also deal with other topics of interest, including contingency planning and legislation. In recent years, the conference has attracted about 200 people each year from 20 countries. The different sessions at this conference were entitled: (1) physical and chemical properties and behaviour of spilled oil, (2) activity updates and contingency planning, (3) detection, tracking and remote sensing, (4) biological effects of oil and hydrocarbons and oil biodegradation, (5) technical seminar on chemical spills with a special session on counter-terrorism, (6) technical seminar on chemical spills, (7) containment and recovery, (8) BIOSS, (9) in-situ burning and shoreline protection and cleanup, (10) oil spill treating agents, (11) spill modelling, and, (12) recent spill experiences. Several presentations described the process of oil in water interactions and were aimed at optimizing response functions, strategy development for marine oil spill response, equipment deployment, containment, recovery, and shoreline assessment. Several studies also presented new treatments for oil spills. Relevant papers and/or presentations were indexed separately for inclusion in the database

Evidence of recent changes in the ice regime of lakes in the Canadian High Arctic from spaceborne satellite observations

Science.gov (United States)

Surdu, Cristina M.; Duguay, Claude R.; Fernández Prieto, Diego

2016-05-01

Arctic lakes, through their ice cover phenology, are a key indicator of climatic changes that the high-latitude environment is experiencing. In the case of lakes in the Canadian Arctic Archipelago (CAA), many of which are ice covered more than 10 months per year, warmer temperatures could result in ice regime shifts. Within the dominant polar-desert environment, small local warmer areas have been identified. These relatively small regions - polar oases - with longer growing seasons and greater biological productivity and diversity are secluded from the surrounding barren polar desert. The ice regimes of 11 lakes located in both polar-desert and polar-oasis environments, with surface areas between 4 and 542 km2, many of unknown bathymetry, were documented. In order to investigate the response of ice cover of lakes in the CAA to climate conditions during recent years, a 15-year time series (1997-2011) of RADARSAT-1/2 ScanSAR Wide Swath, ASAR Wide Swath, and Landsat acquisitions were analyzed. Results show that melt onset occurred earlier for all observed lakes. With the exception of Lower Murray Lake, all lakes experienced earlier summer ice minimum and water-clear-of-ice (WCI) dates, with greater changes being observed for polar-oasis lakes (9-24 days earlier WCI dates for lakes located in polar oases and 2-20 days earlier WCI dates for polar-desert lakes). Additionally, results suggest that some lakes may be transitioning from a perennial/multiyear to a seasonal ice regime, with only a few lakes maintaining a multiyear ice cover on occasional years. Aside Lake Hazen and Murray Lakes, which preserved their ice cover during the summer of 2009, no residual ice was observed on any of the other lakes from 2007 to 2011.

Polar Bear Population Status in the Southern Beaufort Sea

Science.gov (United States)

Regehr, Eric V.; Amstrup, Steven C.; Stirling, Ian

2006-01-01

Polar bears depend entirely on sea ice for survival. In recent years, a warming climate has caused major changes in the Arctic sea ice environment, leading to concerns regarding the status of polar bear populations. Here we present findings from long-term studies of polar bears in the southern Beaufort Sea (SBS) region of the U.S. and Canada, which are relevant to these concerns. We applied open population capture-recapture models to data collected from 2001 to 2006, and estimated there were 1,526 (95% CI = 1,211; 1,841) polar bears in the SBS region in 2006. The number of polar bears in this region was previously estimated to be approximately 1,800. Because precision of earlier estimates was low, our current estimate of population size and the earlier ones cannot be statistically differentiated. For the 2001-06 period, the best fitting capture-recapture model provided estimates of total apparent survival of 0.43 for cubs of the year (COYs), and 0.92 for all polar bears older than COYs. Because the survival rates for older polar bears included multiple sex and age strata, they could not be compared to previous estimates. Survival rates for COYs, however, were significantly lower than estimates derived in earlier studies (P = 0.03). The lower survival of COYs was corroborated by a comparison of the number of COYs per adult female for periods before (1967-89) and after (1990-2006) the winter of 1989-90, when warming temperatures and altered atmospheric circulation caused an abrupt change in sea ice conditions in the Arctic basin. In the latter period, there were significantly more COYs per adult female in the spring (P = 0.02), and significantly fewer COYs per adult female in the autumn (P adult males captured from 1990 to 2006 were smaller than those captured before 1990. The smaller stature of males was especially notable because it corresponded with a higher mean age of adult males. Male polar bears continue to grow into their teens, and if adequately nourished

The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation

NARCIS (Netherlands)

Cózar, Andrés; Martí, Elisa; Duarte, Carlos M; García-de-Lomas, Juan; van Sebille, Erik|info:eu-repo/dai/nl/304831921; Ballatore, Thomas J; Eguíluz, Victor M; González-Gordillo, J Ignacio; Pedrotti, Maria L; Echevarría, Fidel; Troublè, Romain; Irigoien, Xabier

The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively

Drivers of 2016 record Arctic warmth assessed using climate simulations subjected to Factual and Counterfactual forcing

Directory of Open Access Journals (Sweden)

Lantao Sun

2018-03-01

Full Text Available A suite of historical atmospheric model simulations is described that uses a hierarchy of global boundary forcings designed to inform research on the detection and attribution of weather and climate-related extremes. In addition to experiments forced by actual variations in sea surface temperature, sea ice concentration, and atmospheric chemical composition (so-called Factual experiments; additional (Counterfactual experiments are conducted in which the boundary forcings are adjusted by removing estimates of long-term climate change. A third suite of experiments are identical to the Factual runs except that sea ice concentrations are set to climatological conditions (Clim-Polar experiments. These were used to investigate the cause for extremely warm Arctic surface temperature during 2016.Much of the magnitude of surface temperature anomalies averaged poleward of 65°N in 2016 (3.2 ± 0.6 °C above a 1980–89 reference is shown to have been forced by observed global boundary conditions. The Factual experiments reveal that at least three quarters of the magnitude of 2016 annual mean Arctic warmth was forced, with considerable sensitivity to assumptions of sea ice thickness change. Results also indicate that 30–40% of the overall forced Arctic warming signal in 2016 originated from drivers outside of the Arctic. Despite such remote effects, the experiments reveal that the extreme magnitude of the 2016 Arctic warmth could not have occurred without consideration of the Arctic sea ice loss. We find a near-zero probability for Arctic surface temperature to be as warm as occurred in 2016 under late-19th century boundary conditions, and also under 2016 boundary conditions that do not include the depleted Arctic sea ice. Results from the atmospheric model experiments are reconciled with coupled climate model simulations which lead to a conclusion that about 60% of the 2016 Arctic warmth was likely attributable to human-induced climate change

Recent results on polarizations and the present status of the Fermilab polarized beams

International Nuclear Information System (INIS)

Yokosawa, Akihiko.

1986-01-01

Experimental results are reviewed on polarization phenomena in nucleon-nucleon scattering at intermediate energies. The present status of S = 0 dibaryon resonances is presented. The status of the Fermilab polarized beam program is presented, including the construction of polarized beam, two polarimeters being installed in the experimental hall, and the experimental program

The freshwater balance of polar regions in transient simulations from 1500 to 2100 AD using a comprehensive coupled climate model

Energy Technology Data Exchange (ETDEWEB)

Lehner, Flavio; Raible, Christoph C.; Hofer, Dominik; Stocker, Thomas F. [University of Bern, Climate and Environmental Physics, Physics Institute, and Oeschger Centre for Climate Change Research, Bern (Switzerland)

2012-07-15

The ocean and sea ice in both polar regions are important reservoirs of freshwater within the climate system. While the response of these reservoirs to future climate change has been studied intensively, the sensitivity of the polar freshwater balance to natural forcing variations during preindustrial times has received less attention. Using an ensemble of transient simulations from 1500 to 2100 AD we put present-day and future states of the polar freshwater balance in the context of low frequency variability of the past five centuries. This is done by focusing on different multi-decadal periods of characteristic external forcing. In the Arctic, freshwater is shifted from the ocean to sea ice during the Maunder Minimum while the total amount of freshwater within the Arctic domain remains unchanged. In contrast, the subsequent Dalton Minimum does not leave an imprint on the slow-reacting reservoirs of the ocean and sea ice, but triggers a drop in the import of freshwater through the atmosphere. During the twentieth and twenty-first century the build-up of freshwater in the Arctic Ocean leads to a strengthening of the liquid export. The Arctic freshwater balance is shifted towards being a large source of freshwater to the North Atlantic ocean. The Antarctic freshwater cycle, on the other hand, appears to be insensitive to preindustrial variations in external forcing. In line with the rising temperature during the industrial era the freshwater budget becomes increasingly unbalanced and strengthens the high latitude's Southern Ocean as a source of liquid freshwater to lower latitude oceans. (orig.)

The major stratospheric final warming in 2016: dispersal of vortex air and termination of Arctic chemical ozone loss

Directory of Open Access Journals (Sweden)

G. L. Manney

2016-12-01

Full Text Available The 2015/16 Northern Hemisphere winter stratosphere appeared to have the greatest potential yet seen for record Arctic ozone loss. Temperatures in the Arctic lower stratosphere were at record lows from December 2015 through early February 2016, with an unprecedented period of temperatures below ice polar stratospheric cloud thresholds. Trace gas measurements from the Aura Microwave Limb Sounder (MLS show that exceptional denitrification and dehydration, as well as extensive chlorine activation, occurred throughout the polar vortex. Ozone decreases in 2015/16 began earlier and proceeded more rapidly than those in 2010/11, a winter that saw unprecedented Arctic ozone loss. However, on 5–6 March 2016 a major final sudden stratospheric warming ("major final warming", MFW began. By mid-March, the mid-stratospheric vortex split after being displaced far off the pole. The resulting offspring vortices decayed rapidly preceding the full breakdown of the vortex by early April. In the lower stratosphere, the period of temperatures low enough for chlorine activation ended nearly a month earlier than that in 2011 because of the MFW. Ozone loss rates were thus kept in check because there was less sunlight during the cold period. Although the winter mean volume of air in which chemical ozone loss could occur was as large as that in 2010/11, observed ozone values did not drop to the persistently low values reached in 2011.We use MLS trace gas measurements, as well as mixing and polar vortex diagnostics based on meteorological fields, to show how the timing and intensity of the MFW and its impact on transport and mixing halted chemical ozone loss. Our detailed characterization of the polar vortex breakdown includes investigations of individual offspring vortices and the origins and fate of air within them. Comparisons of mixing diagnostics with lower-stratospheric N2O and middle-stratospheric CO from MLS (long-lived tracers show rapid vortex erosion and

Surviving extreme polar winters by desiccation: clues from Arctic springtail (Onychiurus arcticus EST libraries

Directory of Open Access Journals (Sweden)

Kube Michael

2007-12-01

Full Text Available Abstract Background Ice, snow and temperatures of -14°C are conditions which most animals would find difficult, if not impossible, to survive in. However this exactly describes the Arctic winter, and the Arctic springtail Onychiurus arcticus regularly survives these extreme conditions and re-emerges in the spring. It is able to do this by reducing the amount of water in its body to almost zero: a process that is called "protective dehydration". The aim of this project was to generate clones and sequence data in the form of ESTs to provide a platform for the future molecular characterisation of the processes involved in protective dehydration. Results Five normalised libraries were produced from both desiccating and rehydrating populations of O. arcticus from stages that had previously been defined as potentially informative for molecular analyses. A total of 16,379 EST clones were generated and analysed using Blast and GO annotation. 40% of the clones produced significant matches against the Swissprot and trembl databases and these were further analysed using GO annotation. Extraction and analysis of GO annotations proved an extremely effective method for identifying generic processes associated with biochemical pathways, proving more efficient than solely analysing Blast data output. A number of genes were identified, which have previously been shown to be involved in water transport and desiccation such as members of the aquaporin family. Identification of these clones in specific libraries associated with desiccation validates the computational analysis by library rather than producing a global overview of all libraries combined. Conclusion This paper describes for the first time EST data from the arctic springtail (O. arcticus. This significantly enhances the number of Collembolan ESTs in the public databases, providing useful comparative data within this phylum. The use of GO annotation for analysis has facilitated the identification of a

Mercury in the Canadian Arctic terrestrial environment: an update.

Science.gov (United States)

Gamberg, Mary; Chételat, John; Poulain, Alexandre J; Zdanowicz, Christian; Zheng, Jiancheng

2015-03-15

Contaminants in the Canadian Arctic have been studied over the last twenty years under the guidance of the Northern Contaminants Program. This paper provides the current state of knowledge on mercury (Hg) in the Canadian Arctic terrestrial environment. Snow, ice, and soils on land are key reservoirs for atmospheric deposition and can become sources of Hg through the melting of terrestrial ice and snow and via soil erosion. In the Canadian Arctic, new data have been collected for snow and ice that provide more information on the net accumulation and storage of Hg in the cryosphere. Concentrations of total Hg (THg) in terrestrial snow are highly variable but on average, relatively low (Porcupine caribou herd vary among years but there has been no significant increase or decrease over the last two decades. Copyright © 2014 Elsevier B.V. All rights reserved.

Marine Mammals and Climate Change in the Pacific Arctic: Impacts & Resilience

Science.gov (United States)

Moore, S. E.

2014-12-01

Extreme reductions in Arctic sea ice extent and thickness have become a hallmark of climate change, but impacts to the marine ecosystem are poorly understood. As top predators, marine mammals must adapt to biological responses to physical forcing and thereby become sentinels to ecosystem variability and reorganization. Recent sea ice retreats have influenced the ecology of marine mammals in the Pacific Arctic sector. Walruses now often haul out by the thousands along the NW Alaska coast in late summer, and reports of harbor porpoise, humpback, fin and minke whales in the Chukchi Sea demonstrate that these temperate species routinely occur there. In 2010, satellite tagged bowhead whales from Atlantic and Pacific populations met in the Northwest Passage, an overlap thought precluded by sea ice since the Holocene. To forage effectively, baleen whales must target dense patches of zooplankton and small fishes. In the Pacific Arctic, bowhead and gray whales appear to be responding to enhanced prey availability delivered both by new production and advection pathways. Two programs, the Distributed Biological Observatory (DBO) and the Synthesis of Arctic Research (SOAR), include tracking of marine mammal and prey species' responses to ecosystem shifts associated with sea ice loss. Both programs provide an integrated-ecosystem baseline in support of the development of a web-based Marine Mammal Health Map, envisioned as a component of the U.S. Integrated Ocean Observing System (IOOS). An overarching goal is to identify ecological patterns for marine mammals in the 'new' Arctic, as a foundation for integrative research, local response and adaptive management.

Biodiversity, Distributions and Adaptations of Arctic Species in the Context of Environmental Change

Energy Technology Data Exchange (ETDEWEB)

Callaghan, Terry V. [Abisko Scientific Research Station, Abisko (Sweden); Bjoern, Lars Olof [Lund Univ. (Sweden). Dept. of Cell and Organism Biology; Chernov, Yuri [Russian Academy of Sciences, Moscow (Russian Federation). A.N. Severtsov Inst. of Evolutionary Morphology and Animal Ecology] (and others)

2004-11-01

The individual of a species is the basic unit which responds to climate and UV-B changes, and it responds over a wide range of time scales. The diversity of animal, plant and microbial species appears to be low in the Arctic, and decreases from the boreal forests to the polar deserts of the extreme North but primitive species are particularly abundant. This latitudinal decline is associated with an increase in superdominant species that occupy a wide range of habitats. Climate warming is expected to reduce the abundance and restrict the ranges of such species and to affect species at their northern range boundaries more than in the South: some Arctic animal and plant specialists could face extinction. Species most likely to expand into tundra are boreal species that currently exist as outlier populations in the Arctic. Many plant species have characteristics that allow them to survive short snow-free growing seasons, low solar angles, permafrost and low soil temperatures, low nutrient availability and physical disturbance. Many of these characteristics are likely to limit species' responses to climate warming, but mainly because of poor competitive ability compared with potential immigrant species. Terrestrial Arctic animals possess many adaptations that enable them to persist under a wide range of temperatures in the Arctic. Many escape unfavorable weather and resource shortage by winter dormancy or by migration. The biotic environment of Arctic animal species is relatively simple with few enemies, competitors, diseases, parasites and available food resources. Terrestrial Arctic animals are likely to be most vulnerable to warmer and drier summers, climatic changes that interfere with migration routes and staging areas, altered snow conditions and freeze-thaw cycles in winter, climate-induced disruption of the seasonal timing of reproduction and development, and influx of new competitors, predators, parasites and diseases. Arctic microorganisms are also well

A 21-Year Record of Arctic Sea Ice Extents and Their Regional, Seasonal, and Monthly Variability and Trends

Science.gov (United States)

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

2001-01-01

Satellite passive-microwave data have been used to calculate sea ice extents over the period 1979-1999 for the north polar sea ice cover as a whole and for each of nine regions. Over this 21-year time period, the trend in yearly average ice extents for the ice cover as a whole is -32,900 +/- 6,100 sq km/yr (-2.7 +/- 0.5 %/decade), indicating a reduction in sea ice coverage that has decelerated from the earlier reported value of -34,000 +/- 8,300 sq km/yr (-2.8 +/- 0.7 %/decade) for the period 1979-1996. Regionally, the reductions are greatest in the Arctic Ocean, the Kara and Barents Seas, and the Seas of Okhotsk and Japan, whereas seasonally, the reductions are greatest in summer, for which season the 1979-1999 trend in ice extents is -41,600 +/- 12,900 sq km/ yr (-4.9 +/- 1.5 %/decade). On a monthly basis, the reductions are greatest in July and September for the north polar ice cover as a whole, in September for the Arctic Ocean, in June and July for the Kara and Barents Seas, and in April for the Seas of Okhotsk and Japan. Only two of the nine regions show overall ice extent increases, those being the Bering Sea and the Gulf of St. Lawrence.For neither of these two regions is the increase statistically significant, whereas the 1079 - 1999 ice extent decreases are statistically significant at the 99% confidence level for the north polar region as a whole, the Arctic Ocean, the Seas of Okhotsk and Japan, and Hudson Bay.

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;