Warm the Arctic, warm the planet

Warming up the Arctic invokes a number of positive feedbacks that will cause further warming. The reduction in sea ice reduces the polar albedo and instead of the ice reflecting sunlight back into space, the dark waters of the exposed ocean absorb it, warming the waters further, melting more ice and making it harder for it to refreeze. 1st-year ice rebounds in the winter won't make up the difference in this cycle.

Next up: warming the permafrost. This releases more CO2 to the atmosphere, as shown in an about-to-be-published study:

Arctic CO2 Fueling Fierce Global Warming Cycle

The European researchers, led by Ellen Dorrepaal of the University of Amsterdam, artificially warmed plots of natural peatlands in Abisko, in northern Sweden, by 1.0 C over an eight year time period. They found the plots released an extra 60 percent of CO2 in Spring and 52 percent in Summer over the entire period.

"Climate warming therefore accelerates respiration of the extensive, subsurface carbon reservoir in peatlands to a much larger extent than previously thought," the AFP news agency quoted the researchers as saying.

The study’s findings underscore the intense sensitivity of northern peatland carbon reservoirs to climate change, and the peril of a "positive feedback" cycle in which the CO2 released into the atmosphere fuels additional global warming.

OH Great.