From Truth Out: http://www.truth-out.org/climate-change-alaska-and-hawaii-roadmaps-federal-adaptation-policies/1316196527
by: Christine Shearer, Truthout
Monday 10 October 2011
Alaska and Hawaii, the newest states of the United States, represent some of its most extreme climates: Alaska in the remote Arctic and Hawaii in the tropics. Both are being affected by the increasing concentration of heat-absorbing greenhouse gases as the steady cold of Alaska and the warmth of Hawaii represent delicate ecosystems whose balance can be radically affected by subtle shifts in climate.
Average temperatures in the Arctic are warming about twice as fast as the global average, while Hawaii's surface temperatures are increasing at half the global average, although this varies by elevation (temperatures at higher elevations are above the global average). The disparate effects taking place on these states offer us a window into adaptation policies that could benefit the United States as a whole.
Alaska
The stable cold of the Arctic plays an important role in balancing the overall energy of the earth. Its ice reflects most of the sun's rays back to space, while its subsurface provides the cold, saline-rich waters that help drive ocean circulation patterns.
The overall cooling effect, however, is being compromised by global warming. Glaciers are melting, and the newly exposed water absorbs more heat, increasing the amount of warm air over the pole. This warm air, in turn, is changing atmospheric wind patterns, disrupting the normally tight loop of the polar vortex and allowing cold Arctic air to spill south. Research suggests this "warm Arctic/cold continents" pattern was a large factor in the heavy snows experienced in parts of the Northern Hemisphere, including the United States, in the winters of 2009 and 2010, aggravated by moisture from El Niño.
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