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2012 Arctic Report Card Tracking recent environmental changes. Martin Jeffries 1 , J. E. Overland 2 , J. A. Richter-Menge 3 , and N. N. Soreide 2
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2012 Arctic Report Card Tracking recent environmental changes Martin Jeffries1, J. E. Overland2, J. A. Richter-Menge3, and N. N. Soreide2 1 Office of Naval Research & University of Alaska Fairbanks, Arlington, VA2 NOAA Pacific Marine Environmental Laboratory, Seattle, WA, USA3 US Army Corps of Engineers, Cold Regions Research and Engineering Laboratory
Arctic Report Card 2012 • Sponsored by the Arctic Research Program in the NOAA Climate Program Office • 6th annual update of the Arctic Report Card (first published in 2006) • 20 essays developed by 141 authors from 15 different countries • Independent peer-review organized by the Arctic Monitoring and Assessment Programme (AMAP) of the international Arctic Council
Headlines http://www.arctic.noaa.gov/reportcartd/
Highlights http://www.arctic.noaa.gov/reportcartd/
Video http://www.arctic.noaa.gov/reportcartd/
Detailed Essays http://www.arctic.noaa.gov/reportcartd/
Arctic Report Card 2012 What’s New in 2012?
Record-setting changesoccurring repeatedly & faster than expected Record low June snow extent in North America and Eurasia Record low Arctic sea ice extent & thickness Record losses of Greenland ice sheet
Greenland ice sheet loss Record-setting surface melting, ice area and volume losses. Standardized Melt Index (SMI) Area-averaged albedo (Jun-Aug) Reflectivity Melt Rare July melt event impacted 97% of surface area Loss of ice sheet mass Melt Area Jul 8, 2012 Jul 12, 2012
Sea ice extent The continued decline in sea ice is indicative of a shift to a new state of reduced sea ice coverage The minimum Arctic sea ice extent in 2012 was nearly half the values seen from 1979-2000. September 16, 2012
Sea ice thickness January 1987 Older, thicker sea ice continues to be replaced by younger, thinner sea ice Older, thicker sea ice shown in white January 2012 http://www.climatewatch.noaa.gov/article/2012/arctic-sea-ice-getting-thinner-younger
Snow extent June snow extent in the northern hemisphere set record lows repeatedly in the past 5 years in N America and Eurasia. June 1971-2000 June 2012 Impacts the length of the growing season, the timing and dynamics of spring river runoff, the ground thermal regime, and wildlife population dynamics. June snow extent has decreased faster (-17.6 % /decade) than September sea ice extent (-13% /decade)
Changes in Arctic marine ecosystem Massive plankton blooms under thinning ice pack. New habitat for algae in “melt holes” in sea ice Whale population impacts are uncertain. With sea ice declining, gray whales are remaining in the Arctic longer Under-ice phytoplankton bloom “… profound, continuing changes in the Arctic marine ecosystem” Shifts in primary and secondary production have direct impacts on benthic communities Seabirds , indicators of changing marine conditions, are showing changes in diet, foraging behavior and survival rates.
Land Tundra, adjacent to the expanding ocean open in summer, is seeing an increase in biomass, greenness, length of growing season and summer warmth. Permafrost temperatures Permafrost temperature below the tundra land surface is increasing partially due to greater summer warmth following the earlier retreat of the snow cover in spring
Land Melting permafrost impacts infrastructure, river runoff, vegetation, growing season, turndra fires 16
Land animals Strong regional variation in caribou and reindeer populations. Lemming (small rodent) population density decreasing, may be influenced by snow characteristics Arctic fox population linked to lemming (food) abundance and northward territorial expansion of the larger Red fox.
Arctic Report Card 2012www.arctic.noaa.gov/reportcard Record low June snow extent in North America and Eurasia Record low June snow extent in North America and Eurasia Record low Arctic sea ice extent & thickness Record losses of Greenland ice sheet Record losses of Greenland ice sheet Multiple, record-breaking and recurring changes provide strong evidence that the Arctic system is entering a new state