|Rapid Change (This Past Year)|
|Atmosphere (D): Higher temperatures in the Arctic and unusually lower temperatures in
some low latitude regions are linked to global shifts in atmospheric
Sea Ice (C-): A shift in the Arctic Ocean system since 2007 is indicated by the decline in ice age and summer extent, and the warmer, fresher upper ocean.
Hydrology (C): Continued dramatic loss of ice sheet and glacier mass, reduced snow extent and duration, and increasing permafrost temperatures are linked to higher Arctic air temperatures.
Moderate Change (This Past Year)
Marine Ecosystems (C+): Since 1998, biological productivity at the base of the food chain has increased by 20%. Polar bears and walrus continue to lose habitat in Alaskan waters.
Terrestrial Ecosystems (B-): Increased “greenness” of tundra vegetation in Eurasia and North America linked to increase in open water and warmer land temperatures in coastal regions.