|What's new in 2015?
Maximum sea ice extent on 25 February was 15 days earlier than average and the lowest value on record (1979-present). Minimum ice extent in September was the 4th lowest on record. Sea ice continues to be younger and thinner: in February and March 2015 there was twice as much first-year ice as there was 30 years ago.
Changes in sea ice alone are having profound effects on the marine ecosystem (fishes, walruses, primary production) and sea surface temperatures.
|Air temperatures in all seasons between October 2014 and September 2015 exceeded 3°C above average over broad areas of the Arctic, while the annual average air temperature (+1.3°) over land was the highest since 1900.||The 2nd lowest June snow cover extent on land continued a decrease that dates back to 1979, while river discharge from the great rivers of Eurasia and North America has increased during that time.||Melting occurred over more than 50% of the Greenland Ice Sheet for the first time since the exceptional melting of 2012, and glaciers terminating in the ocean showed an increase in ice velocity and decrease in area.|
|Walruses are negatively affected by loss of sea ice habitat but positively affected by reduced hunting pressure, while sea ice loss and rising temperatures in the Barents Sea are causing a poleward shift in fish communities.||Widespread positive sea surface temperature and primary production anomalies occurred throughout the Arctic Ocean and adjacent seas as sea ice retreated in summer 2015.||Terrestrial vegetation productivity and above-ground biomass have been decreasing since 2011.|