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Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss

https://arctichealth.org/en/permalink/ahliterature275999
Source
Geophysical Research Letters. 2008 Jun;35(11):1-6
Publication Type
Article
Date
Jun-2008
Author
Lawrence, DM
Slater, AG
Tomas, RA
Holland, MM
Deser, C
Source
Geophysical Research Letters. 2008 Jun;35(11):1-6
Date
Jun-2008
Language
English
Publication Type
Article
Keywords
Albedo
Arctic sea ice
Arctic warming
Land temperature
Permafrost
Abstract
Coupled climate models and recent observational evidence suggest that Arctic sea ice may undergo abrupt periods of loss during the next fifty years. Here, we evaluate how rapid sea ice loss affects terrestrial Arctic climate and ground thermal state in the Community Climate System Model. We find that simulated western Arctic land warming trends during rapid sea ice loss are 3.5 times greater than secular 21st century climate-change trends. The accelerated warming signal penetrates up to 1500 km inland and is apparent throughout most of the year, peaking in autumn. Idealized experiments using the Community Land Model, with improved permafrost dynamics, indicate that an accelerated warming period substantially increases ground heat accumulation. Enhanced heat accumulation leads to rapid degradation of warm permafrost and may increase the vulnerability of colder permafrost to degradation under continued warming. Taken together, these results imply a link between rapid sea ice loss and permafrost health.
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Aragonite undersaturation in the Arctic Ocean: Effects of ocean acidification and sea ice melt

https://arctichealth.org/en/permalink/ahliterature276001
Source
Science. 2009 Nov;326(5956):1098-1100
Publication Type
Article
Date
Nov-2009
Author
Yamamoto-Kawai, M
McLaughlin, FA
Carmack, EC
Nishino, S
Shimada, K
Author Affiliation
Department of Fisheries and Oceans, Institute of Ocean Sciences, Sidney, British Columbia
Source
Science. 2009 Nov;326(5956):1098-1100
Date
Nov-2009
Language
English
Publication Type
Article
Keywords
Aragonite
Arctic Ocean
Calcium Carbonate
Canada Basin
Carbon dioxide emissions
Sea ice melt
Abstract
The increase in anthropogenic carbon dioxide emissions and attendant increase in ocean acidification and sea ice melt act together to decrease the saturation state of calcium carbonate in the Canada Basin of the Arctic Ocean. In 2008, surface waters were undersaturated with respect to aragonite, a relatively soluble form of calcium carbonate found in plankton and invertebrates. Undersaturation was found to be a direct consequence of the recent extensive melting of sea ice in the Canada Basin. In addition, the retreat of the ice edge well past the shelf-break has produced conditions favorable to enhanced upwelling of subsurface, aragonite-undersaturated water onto the Arctic continental shelf. Undersaturation will affect both planktonic and benthic calcifying biota and therefore the composition of the Arctic ecosystem.
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Arctic climate change: Observed and modelled temperature and sea-ice variability

https://arctichealth.org/en/permalink/ahliterature276002
Source
Tellus. 2004 56(4):328-341
Publication Type
Article
Date
2004
  1 website  
Author
Johannessen, OM
Bengtsson, L
Miles, MW
Kuzmina, SI
Semenov, VA
Alekseev, GV
Nagurnyi, AP
Zakharov, VF
Bobylev, LP
Pettersson, LH
Hasselmann, K
Cattle, HP
Source
Tellus. 2004 56(4):328-341
Date
2004
Language
English
Publication Type
Article
Keywords
Arctic climate system
Greenhouse-gas forcing
Observational data
Predictions
Sea-ice variability
Abstract
Changes apparent in the arctic climate system in recent years require evaluation in a century-scale perspective in order to assess the Arctic's response to increasing anthropogenic greenhouse-gas forcing. Here, a new set of century and multidecadal-scale observational data of surface air temperature (SAT) and sea ice is used in combination with ECHAM4 and HadCM3 coupled atmosphere-ice-ocean global model simulations in order to better determine and understand arctic climate variability. We show that two pronounced twentieth-century warming events, both amplified in the Arctic, were linked to sea-ice variability. SAT observations and model simulations indicate that the nature of the arctic warming in the last two decades is distinct from the early twentieth-century warm period. It is suggested strongly that the earlier warming was natural internal climate-system variability, whereas the recent SAT changes are a response to anthropogenic forcing. The area of arctic sea ice is furthermore observed to have decreased ~8 x 105 km2 (7.4%) in the past quarter century, with record-low summer ice coverage in September 2002. A set of model predictions is used to quantify changes in the ice cover through the twenty-first century, with greater reductions expected in summer than winter. In summer, a predominantly sea-ice-free Arctic is predicted for the end of this century.
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Arctic Ocean sea ice drift origin derived from artificial radionuclides

https://arctichealth.org/en/permalink/ahliterature102087
Source
Science of the Total Environment. 2010 Jul;408(16):3349-3358
Publication Type
Article
Date
Jul-2010
Author
Cámara-Mor, P
Masqué, P
Garcia-Orellana, J
Cochran, JK
Mas, JL
Chamizo, E
Hanfland, C
Author Affiliation
Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain
Source
Science of the Total Environment. 2010 Jul;408(16):3349-3358
Date
Jul-2010
Language
English
Publication Type
Article
Keywords
Arctic Regions
Oceans and Seas
Radioisotopes--analysis
Sea ice
Abstract
Since the 1950s, nuclear weapon testing and releases from the nuclear industry have introduced anthropogenic radionuclides into the sea, and in many instances their ultimate fate are the bottom sediments. The Arctic Ocean is one of the most polluted in this respect, because, in addition to global fallout, it is impacted by regional fallout from nuclear weapon testing, and indirectly by releases from nuclear reprocessing facilities and nuclear accidents. Sea-ice formed in the shallow continental shelves incorporate sediments with variable concentrations of anthropogenic radionuclides that are transported through the Arctic Ocean and are finally released in the melting areas. In this work, we present the results of anthropogenic radionuclide analyses of sea-ice sediments (SIS) collected on five cruises from different Arctic regions and combine them with a database including prior measurements of these radionuclides in SIS. The distribution of (137)Cs and (239,240)Pu activities and the (240)Pu/(239)Pu atom ratio in SIS showed geographical differences, in agreement with the two main sea ice drift patterns derived from the mean field of sea-ice motion, the Transpolar Drift and Beaufort Gyre, with the Fram Strait as the main ablation area. A direct comparison of data measured in SIS samples against those reported for the potential source regions permits identification of the regions from which sea ice incorporates sediments. The (240)Pu/(239)Pu atom ratio in SIS may be used to discern the origin of sea ice from the Kara-Laptev Sea and the Alaskan shelf. However, if the (240)Pu/(239)Pu atom ratio is similar to global fallout, it does not provide a unique diagnostic indicator of the source area, and in such cases, the source of SIS can be constrained with a combination of the (137)Cs and (239,240)Pu activities. Therefore, these anthropogenic radionuclides can be used in many instances to determine the geographical source area of sea-ice.
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Arctic Ocean synthesis: analysis of climate change impacts in the Chukchi and Beaufort Seas with strategies for future research.

https://arctichealth.org/en/permalink/ahliterature297070
Source
184 p.
Publication Type
Report
Date
December 2008
................................................................................................................................ 3 PHYSICAL OCEANOGRAPHY ............................................................................................................. 6 CHEMICAL OCEANOGRAPHY.......................................................................................................... 18 SEA ICE
  1 document  
Author
Hopcroft, Russ
Bluhm, Bodil
Gradinger, Rolf
Author Affiliation
Institute of Marine Sciences, University of Alaska, Fairbanks
Source
184 p.
Date
December 2008
Language
English
Geographic Location
Russia
U.S.
Publication Type
Report
File Size
3882185
Keywords
Chukchi Sea
Beaufort Sea
Sea ice
Coastal erosion
Permafrost
Sea level
Marine wildlife
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Arctic sea ice decline: Faster than forecast

https://arctichealth.org/en/permalink/ahliterature276005
Source
Geophysical Research Letters. 2007 May;34(9):1-5
Publication Type
Article
Date
May-2007
Author
Stroeve, J
Holland, MM
Meier, W
Scambos, T
Serreze, M
Source
Geophysical Research Letters. 2007 May;34(9):1-5
Date
May-2007
Language
English
Publication Type
Article
Keywords
Arctic sea ice
GHG
Greenhouse gas loading
Models
Observations
Panel on Climate Change Fourth Assessment Report
Abstract
From 1953 to 2006, Arctic sea ice extent at the end of the melt season in September has declined sharply. All models participating in the Intergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4) show declining Arctic ice cover over this period. However, depending on the time window for analysis, none or very few individual model simulations show trends comparable to observations. If the multi-model ensemble mean time series provides a true representation of forced change by greenhouse gas (GHG) loading, 33-38% of the observed September trend from 1953-2006 is externally forced, growing to 47-57% from 1979-2006. Given evidence that as a group, the models underestimate the GHG response, the externally forced component may be larger. While both observed and modeled Antarctic winter trends are small, comparisons for summer are confounded by generally poor model performance.
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Arctic sea ice decline: Projected changes in timing and extent of sea ice in the Bering and Chukchi seas

https://arctichealth.org/en/permalink/ahliterature276006
Source
USGS Open-File Report 2010-1176. iv, 32 p.
Publication Type
Report
Date
2010
Arctic Sea Ice Decline: Projected Changes in Timing and Extent of Sea Ice in the Bering and Chukchi Seas U.S. Department of the Interior U.S. Geological Survey Open-File Report 2010–1176 Cover: Sea ice in the Chukchi Sea on July 9, 2010, in a region northwest of Barrow, Alaska that was
  1 document  
Author
Douglas, DC
Author Affiliation
U.S. Geological Survey
Source
USGS Open-File Report 2010-1176. iv, 32 p.
Date
2010
Language
English
Publication Type
Report
File Size
5008237
Keywords
Bering Sea
Chukchi Sea
GCMs
General circulation models
Satellite data
Sea ice
Abstract
The Arctic region is warming faster than most regions of the world due in part to increasing greenhouse gases and positive feedbacks associated with the loss of snow and ice cover. One consequence has been a rapid decline in Arctic sea ice over the past 3 decades—a decline that is projected to continue by state-of-the-art models. Many stakeholders are therefore interested in how global warming may change the timing and extent of sea ice Arctic-wide, and for specific regions. To inform the public and decision makers of anticipated environmental changes, scientists are striving to better understand how sea ice influences ecosystem structure, local weather, and global climate. Here, projected changes in the Bering and Chukchi Seas are examined because sea ice influences the presence of, or accessibility to, a variety of local resources of commercial and cultural value. In this study, 21st century sea ice conditions in the Bering and Chukchi Seas are based on projections by 18 general circulation models (GCMs) prepared for the fourth reporting period by the Intergovernmental Panel on Climate Change (IPCC) in 2007. Sea ice projections are analyzed for each of two IPCC greenhouse gas forcing scenarios: the A1B ‘business as usual’ scenario and the A2 scenario that is somewhat more aggressive in its CO2 emissions during the second half of the century. A large spread of uncertainty among projections by all 18 models was constrained by creating model subsets that excluded GCMs that poorly simulated the 1979–2008 satellite record of ice extent and seasonality.
At the end of the 21st century (2090–2099), median sea ice projections among all combinations of model ensemble and forcing scenario were qualitatively similar. June is projected to experience the least amount of sea ice loss among all months. For the Chukchi Sea, projections show extensive ice melt during July and ice-free conditions during August, September, and October by the end of the century, with high agreement among models. High agreement also accompanies projections that the Chukchi Sea will be completely ice covered during February, March, and April at the end of the century. Large uncertainties, however, are associated with the timing and amount of partial ice cover during the intervening periods of melt and freeze. For the Bering Sea, median March ice extent is projected to be about 25 percent less than the 1979–1988 average by mid-century and 60 percent less by the end of the century. The ice-free season in the Bering Sea is projected to increase from its contemporary average of 5.5 months to a median of about 8.5 months by the end of the century. A 3-month longer ice- free season in the Bering Sea is attained by a 1-month advance in melt and a 2-month delay in freeze, meaning the ice edge typically will pass through the Bering Strait in May and January at the end of the century rather than June and November as presently observed.
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Arctic sea ice response to atmospheric forcings with varying levels of anthropogenic warming and climate variability

https://arctichealth.org/en/permalink/ahliterature276007
Source
Geophysical Research Letters. 2010 Oct;37:1-6
Publication Type
Article
Date
Oct-2010
Author
Zhang, J
Steele, M
Schweiger1, A
Source
Geophysical Research Letters. 2010 Oct;37:1-6
Date
Oct-2010
Language
English
Publication Type
Article
Keywords
Arctic sea ice
Climate variability
Abstract
Numerical experiments are conducted to project arctic sea ice responses to varying levels of future anthropogenic warming and climate variability over 2010-2050. A summer ice-free Arctic Ocean is likely by the mid-2040s if arctic surface air temperature (SAT) increases 4°C by 2050 and climate variability is similar to the past relatively warm two decades. If such a SAT increase is reduced by one-half or if a future Arctic experiences a range of SAT fluctuation similar to the past five decades, a summer ice-free Arctic Ocean would be unlikely before 2050. If SAT increases 4°C by 2050, summer ice volume decreases to very low levels (10-37% of the 1978-2009 summer mean) as early as 2025 and remains low in the following years, while summer ice extent continues to fluctuate annually. Summer ice volume may be more sensitive to warming while summer ice extent more sensitive to climate variability. The rate of annual mean ice volume decrease relaxes approaching 2050. This is because, while increasing SAT increases summer ice melt, a thinner ice cover increases winter ice growth. A thinner ice cover also results in a reduced ice export, which helps to further slow ice volume loss. Because of enhanced winter ice growth, arctic winter ice extent remains nearly stable and therefore appears to be a less sensitive climate indicator.
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Arctic sea ice retreat in 2007 follows thinning trend

https://arctichealth.org/en/permalink/ahliterature276008
Source
Journal of Climate. 2009 Jan;22(1):165-176
Publication Type
Article
Date
Jan-2009
Author
Lindsay, RW
Zhang, J
Schweiger, A
Steele, M
Stern, H
Author Affiliation
Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, Washington
Source
Journal of Climate. 2009 Jan;22(1):165-176
Date
Jan-2009
Language
English
Publication Type
Article
Keywords
Arctic Ocean
Sea ice
Abstract
The minimum of Arctic sea ice extent in the summer of 2007 was unprecedented in the historical record. A coupled ice-ocean model is used to determine the state of the ice and ocean over the past 29 years to investigate the causes of this ice extent minimum within a historical perspective. It is found that even though the 2007 ice extent was strongly anomalous, the loss in total ice mass was not. Rather, the 2007 ice mass loss is largely consistent with a steady decrease in ice thickness that began in 1987. Since then, the simulated mean September ice thickness within the Arctic Ocean has declined from 3.7 to 2.6 m at a rate of -0.57 m/decade. Both the area coverage of thin ice at the beginning of the melt season and the total volume of ice lost in the summer have been steadily increasing. The combined impact of these two trends caused a large reduction in the September mean ice concentration in the Arctic Ocean. This created conditions during the summer of 2007 that allowed persistent winds to push the remaining ice from the Pacific side to the Atlantic side of the basin and more than usual into the Greenland Sea. This exposed large areas of open water, resulting in the record ice extent anomaly.
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Assessment of the potential health impacts of climate change in Alaska

https://arctichealth.org/en/permalink/ahliterature287905
Source
Bulletin. State of Alaska Epidemiology. Recommendations and Reports. 2018 Jan 8; 20(1)
Publication Type
Article
Date
2018
...........................................................................................................6 2.3.3 Weather Patterns ....................................................................................................6 2.3.4 Sea Ice ....................................................................................................................7 2.3.5 Glaciers
  1 document  
Author
Yoder, Sarah
Author Affiliation
Alaska Section of Epidemiology
Source
Bulletin. State of Alaska Epidemiology. Recommendations and Reports. 2018 Jan 8; 20(1)
Date
2018
Language
English
Geographic Location
U.S.
Publication Type
Article
Digital File Format
Text - PDF
Physical Holding
Alaska Medical Library
Keywords
Alaska
Climate change
Sea levels
Permafrost
Glaciers
Weather patterns
Sea ice
Temperature
Subsistence
Infectious disease
Sanitation
Health services
Abstract
Background: Over the past century, the air and water temperatures in Alaska have warmed considerably faster than in the rest of the United States. Because Alaska is the only Arctic state in the Nation, Alaskans are likely to face some climate change challenges that will be different than those encountered in other states. For example, permafrost currently underlies 80% of Alaska and provides a stable foundation for the physical infrastructure of many Alaska communities. As has already been seen in numerous villages, the groundcover that overlies permafrost is vulnerable to sinking or caving if the permafrost thaws, resulting in costly damage to physical infrastructure. The reliance on subsistence resources is another contrast to many other states. Many Alaskans depend upon subsistence harvests of fish and wildlife resources for food and to support their way of life. Some Alaskans report that the changing environment has already impacted their traditional practices. Many past efforts to characterize the potential impacts of climate change in Alaska have focused primarily on describing expected changes to the physical environment and the ecosystem, and less on describing how these changes, in addition to changes in animal and environmental health, could affect human health. Thus, a careful analysis of how climate change could affect the health of people living in Alaska is warranted. The Alaska Division of Public Health has conducted such an assessment using the Health Impact Assessment (HIA) framework; the assessment is based on the current National Climate Assessment (NCA) predictions for Alaska. The document is intended to provide a broad overview of the potential adverse human health impacts of climate change in Alaska and to present examples of adaptation strategies for communities to consider when planning their own response efforts. This document does not present a new model for climate change in Alaska, and it does not offer a critique of the NCA predictions for Alaska.
Documents

AssessmentofthePotentialHealthImpactsof.pdf

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78 records – page 1 of 8.