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Greenhouse gas mitigation can reduce sea-ice loss and increase polar bear persistence

https://arctichealth.org/en/permalink/ahliterature276032
Source
Nature. 2010 Dec;468:955-958
Publication Type
Article
Date
Dec-16-2010
Author
Amstrup, SC
DeWeaver, ET
Douglas, DC
Marcot, BG
Durner, GM
Bitz, CM
Bailey, DA
Source
Nature. 2010 Dec;468:955-958
Date
Dec-16-2010
Language
English
Publication Type
Article
Keywords
Arctic
Greenhouse gas emissions
Marine ecosystem
Polar bear
Sea ice
Tipping point
Abstract
On the basis of projected losses of their essential sea-ice habitats, a United States Geological Survey research team concluded in 2007 that two-thirds of the world's polar bears (Ursus maritimus) could disappear by mid-century if business-as-usual greenhouse gas emissions continue1. That projection, however, did not consider the possible benefits of greenhouse gas mitigation. A key question is whether temperature increases lead to proportional losses of sea-ice habitat, or whether sea-ice cover crosses a tipping point and irreversibly collapses when temperature reaches a critical threshold. Such a tipping point would mean future greenhouse gas mitigation would confer no conservation benefits to polar bears. Here we show, using a general circulation model, that substantially more sea-ice habitat would be retained if greenhouse gas rise is mitigated. We also show, with Bayesian network model outcomes, that increased habitat retention under greenhouse gas mitigation means that polar bears could persist throughout the century in greater numbers and more areas than in the business-as-usual case. Our general circulation model outcomes did not reveal thresholds leading to irreversible loss of ice; instead, a linear relationship between global mean surface air temperature and sea-ice habitat substantiated the hypothesis that sea-ice thermodynamics can overcome albedo feedbacks proposed to cause sea-ice tipping points. Our outcomes indicate that rapid summer ice losses in models and observations represent increased volatility of a thinning sea-ice cover, rather than tipping-point behaviour. Mitigation-driven Bayesian network outcomes show that previously predicted declines in polar bear distribution and numbers are not unavoidable. Because polar bears are sentinels of the Arctic marine ecosystem, and trends in their sea-ice habitats foreshadow future global changes, mitigating greenhouse gas emissions to improve polar bear status would have conservation benefits throughout and beyond the Arctic.
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Historical analysis of sea ice conditions in M'Clintock Channel and the Gulf of Boothia, Nunavut: Implications for ringed seal and polar bear habitat

https://arctichealth.org/en/permalink/ahliterature276033
Source
Arctic. 2004 Mar;57(1):1-14
Publication Type
Article
Date
Mar-2004
  1 website  
Author
Barber, DG
Iacozza, J
Source
Arctic. 2004 Mar;57(1):1-14
Date
Mar-2004
Language
English
Publication Type
Article
Keywords
Climate variability
Gulf of Boothia
M'Clintock Channel
Nunavut
Phoca hispida
Polar bear
Ringed seal habitat
Sea ice
Ursus maritimus
Abstract
Sea ice is an integral part of the marine ecosystem in the Arctic and important habitat for ringed seals and polar bears. To study changes in sea ice characteristics indicative of ringed seal habitat (and linked, through predator/prey relationships, to polar bear habitat), we examined historical changes in sea ice concentration and type within M'Clintock Channel and the Gulf of Boothia, two regions of the Canadian Arctic Archipelago, during 1980-2000. Results suggest large interannual variability in winter ice conditions over the 21-year study period. In M'Clintock Channel, first-year ice types dominated consistently, while in the Gulf of Boothia, thick ice types dominated in some years. For breakup and consolidation, the regional spatial patterns differed significantly, occurring in opposite directions (N-S vs. S-N) in the two regions. The dates showed considerable interannual variability in both regions, suggesting no clear pattern of either earlier breakup or later consolidation. Analysis of satellite data confirmed the results obtained from digital ice charts. Ringed seal habitat suitability indices (HSI) indicate that both regions contained primary, secondary, and tertiary HSI classes. No trends were evident in the secondary or tertiary classes, but changes in the primary class were evident in M'Clintock Channel over the five-year period 1997-2001. Dynamic and thermodynamic sea ice processes are important to ringed seal habitat (and ultimately, polar bear habitat) at regional and hemispheric scales in the current context of climate variability and change.
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The impact of climate change on the Russian Arctic and paths to solving the problem.

https://arctichealth.org/en/permalink/ahliterature297071
Source
WWF- Russia, Moscow. 2008. 28 p.
Publication Type
Report
Date
2008
5. Vulnerable Natural Boundary Zones 16 6. Polar bears and walruses 18 7. Reindeer 20 8. Commercial Fishing 22 9. Recommendations 24 Bibliography 26 Recommended Internet Sites 27 © Rommel Zulueta © W W F- R us si a / V la d im ir S er tu n © WWF-Russia / Dmitry Karelin
  1 document  
Author
Kokorin, A.O.
Karelin, D.V.
Stetsenko, A.V.
Source
WWF- Russia, Moscow. 2008. 28 p.
Date
2008
Language
English
Geographic Location
Russia
Publication Type
Report
File Size
6672766
Keywords
Climate change
Polar bears
Walruses
Reindeer
Commercial fishing
Abstract
This illustrated and compact brochure presents data on the impact of climate change in the Russian Arctic. The text compiles scientific observations, witness accounts from local residents, and data on current and foreseen damage due to climate change. Alas, the situation in the Arctic is alarming, and the forecasts are discouraging. This fact must be presented in a clear and unambiguous form, and delivered to the leaders of the major world powers, as well as to UN diplomats, currently conducting negotiations towards future reduction of greenhouse gases. Climate change, however, cannot be halted immediately – in the coming decades, both man and the ecosystem will require assistance. The goal of this pamphlet is to show to those in positions of power, in a demonstrative and scientifically sound manner, that it is time to act, particularly in Arctic regions. We must take concrete steps towards adaptation to climate change, and it will be far better and more affordable to take these steps in advance. This brochure was prepared under the auspices of the Artic Project of WWF-Russia, and contains summaries of information gathered within the project’s first year. We propose that this information be used as a basis for planning measures, aimed at adaptation to climate change in the Russian Arctic.
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Man and polar bear in Svalbard: a solvable ecological conflict?

https://arctichealth.org/en/permalink/ahliterature2902
Source
Pages 532-534 in R. Fortuine et al., eds. Circumpolar Health 96. Proceedings of the Tenth International Congress on Circumpolar Health, Anchorage, Alaska, 1996. Int J Circumpolar Health. 1998;57 Supp 1.
Publication Type
Article
Date
1998
Man and Polar Bear in Svalbard: A Solvable Ecological Conflict? T. Risholt1.2, E. Persen3.4, and O.I. Solem1 1 Longyearbyen Hospital, Longyearbyen, Norway 2 Department of Occupational and Environmental Medicine, Telemark Central Hospital, Skien, Norway 3 Environmental Officer, Governor of
  1 document  
Author
Risholt, T.
Persen, E.
Solem, O.I.
Author Affiliation
Longyearbyen Hospital, Norway
Source
Pages 532-534 in R. Fortuine et al., eds. Circumpolar Health 96. Proceedings of the Tenth International Congress on Circumpolar Health, Anchorage, Alaska, 1996. Int J Circumpolar Health. 1998;57 Supp 1.
Date
1998
Language
English
Geographic Location
Norway
Publication Type
Article
Digital File Format
Text - PDF
Physical Holding
University of Alaska Anchorage
Keywords
Injury prevention
Norway
Polar bear-human interaction
Svalbard
Abstract
The objective of this study is twofold. First, it is to assess the nature and magnitude of the polar bear-human conflict with respect to injuries to man and bear. Second, a major concern has been to minimize injurious interactions in order to safeguard the people who live and work in the Arctic, and, at the same time, secure the future of the polar bear in one of the last relatively unspoiled habitats on earth for big carnivores. From 1971 to 1995, approximately 80 bears were involved in serious bear-human interactions. Of these, 77 bears were killed and 3 escaped after having injured people. During the same period, 10 people were injured, 4 of them fatally, in 7 separate interactions, each involving a single bear. None of the victims carried an appropriate firearm. The circumstances leading up to the confrontations give strong reasons for supposing that the majority of the attacks were predatory in nature. Seven of the injured, including the four who were killed, sustained bites to the head and neck. Correct use of firearms could probably have prevented all the fatalities. However, the keeping and use of firearms caused two accidental deaths in the same period. We conclude that alertness, the absence of attractants (food, garbage), and appropriate bear repellents to secure field camps are important items in preventing conflicts and should always be available. However, as a last but indispensable resort, a firearm (rifle or shotgun) carried by an experienced user is the only safe precaution for avoiding injuries in polar bear country. Killing a bear on the rare occasions when humans are in danger presents no threat to the bear population. With regard to physical injury to people, the problem is a minor one. Bears have a dual impact on everyday life in the Svalbard settlements. While there is some anxiety related to the presence of bears, the polar bear is a source of breathtaking adventure highly valued by both residents and visitors.
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Peroxisome proliferator-activate receptors (PPARs) in polar bear (Ursus maritimus) as a target for environmental pollutants

https://arctichealth.org/en/permalink/ahliterature297157
Source
Universitetet i Bergen.
Publication Type
Dissertation
Date
2014
Author
Berg, Mari Katrine
Source
Universitetet i Bergen.
Date
2014
Language
English
Publication Type
Dissertation
Keywords
Arctic
Polar bear
Pollutants
Abstract
Environmental pollutants with metabolic disrupting abilities are present in the Arctic. Particularly high levels of pollutants have been found in the apex predator of the Arctic marine food web, the polar bear. This species is dependent on a highly regulated metabolic system as it undergoes a distinct feasting and fasting regime due to seasonal variation in availability of food. Key regulators in consumption and storage of energy are the peroxisome proliferator-activated receptors (PPARs, NR1C), members of the nuclear receptor superfamily.
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Report of the Eighth Meeting of the U.S.-Russia Polar Bear Commission, November 17-18, 2016, Anchorage, Alaska.

https://arctichealth.org/en/permalink/ahliterature296456
Source
U.S.-Russia Polar Bear Commission.
Publication Type
Conference/Meeting Material
Date
2016
1 Report of the Eighth Meeting of the U.S.-Russia Polar Bear Commission November 17-18, 2016 Anchorage, Alaska The eighth meeting of the U.S.-Russia Polar Bear Commission (hereafter, "Commission") took place November 14-18, 2016 in Anchorage, Alaska, USA. The Commission meeting was
  1 document  
Source
U.S.-Russia Polar Bear Commission.
Date
2016
Language
English
Geographic Location
Russia
U.S.
Publication Type
Conference/Meeting Material
File Size
297288
Keywords
Polar bears
Climate change
Conservation
Sunsistence
Alaska Natives
Chukotka Autonomous Region
Documents

2016_Commission_Report_FINAL_signed.pdf

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Report to the US-Russia Polar Bear Commission: developed by the Scientific Working Group, May 2010.

https://arctichealth.org/en/permalink/ahliterature296753
Source
The Commission.
Publication Type
Report
Date
2010
1 Report to the US-Russia Polar Bear Commission: developed by the Scientific Working Group May 2010 PART 1: Harvest Management I. Background a. Bilateral Agreement and establishment of a Scientific Working Group The bilateral “Agreement between the United States and the
  1 document  
Source
The Commission.
Date
2010
Language
English
Geographic Location
Russia
U.S.
Publication Type
Report
File Size
1444023
Keywords
Polar bear
Harvest management
Alaska
Chukotka
Conservation
Sea ice
Climate change
Documents

SWG_Report_2010_ENG.pdf

Read PDF Online Download PDF
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A step-change in the date of sea-ice breakup in western Hudson Bay

https://arctichealth.org/en/permalink/ahliterature275997
Source
Arctic. 2010 Jun;63(2);155-164
Publication Type
Article
Date
Jun-2010
  1 website  
Author
Scott, JBT
Marshall, GJ
Source
Arctic. 2010 Jun;63(2);155-164
Date
Jun-2010
Language
English
Publication Type
Article
Keywords
Breakup
Climate change
Hudson Bay
Polar bear
Sea ice
Abstract
Over the last four decades there has been a trend to earlier summer breakup of the sea ice in western Hudson Bay, Canada. As this sea ice is critical for the polar bears that use it for hunting, the earlier breakup is believed to be a factor in the declining health of the regional polar bear population. Analysis of the change to earlier breakup using passive microwave satellite data is problematic because of currently unquantifiable systematic errors between different satellites. Analysis using Canadian sea-ice charts from 1971 to 2008 shows that the change to earlier breakup is best represented by a 12-day step. This step occurs from 1988 to 1989 with no significant trend before or after the step. Although not as great as the three-week gradual change suggested by previous studies, this change is still significant. An increase in regional southwesterly winds during the first three weeks of June and a corresponding increase in surface temperature are shown to be likely contributing factors to this earlier breakup. It remains to be seen whether these changes in atmospheric circulation might be ascribed to human actions or simply to natural climate variability.
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The vitamin A content and toxicity of bear and seal liver.

https://arctichealth.org/en/permalink/ahliterature293740
Source
Biochem. J., 37:166-168.
Publication Type
Article
Date
1943
Author
Rodahl, K.
Source
Biochem. J., 37:166-168.
Date
1943
Publication Type
Article
Keywords
Vitamin A
Hypervitaminosis
Polar bear
Seal
Notes
Cited in: Fortuine, Robert. 1968. The Health of the Eskimos: a bibliography 1857-1967. Dartmouth College Libraries. Citation number 989.
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9 records – page 1 of 1.