"If the world goes about its business at the usual rate, all of the ice is likely to melt in the Arctic every summer by 2050—less than 40 years from now. Polar bears will be gone."

this will possibly happen much sooner.

"Wieslaw Maslowski of the Naval Postgraduate School has “projected a (virtually) ice-free fall by 2016 (+/- 3 yrs).” Contrary to some reporting, that projection has been unchanged for years, though Maslowski is in the process of creating a more sophisticated model that he expects “will improve prediction of sea ice melt,” as he explained to me recently."

"In September, National Snow and Ice Data Center’s director Mark Serreze said, “The volume of ice left in the Arctic likely reached the lowest ever level this month” and “I stand by my previous statements that the Arctic summer sea ice cover is in a death spiral. It’s not going to recover.”"

http://thinkprogress.org/romm/2011/05/19/208088/arctic-sea-ice-volume-death-spiral/

http://www.youtube.com/watch?v=DmMYATGma64

Rate of ice cover melt will be able to be better kept track of now that full Arctic maps of ice thickness have been generated monthly and will likely continue. This will enable total volume of ice to be watched as it varies through the seasons.

Searching 'Arctic methane release 2011' gives a listing of articles depicting a glimpse of understanding of a very grave situation facing Nature and life on Earth

Technically shielding the poles from incoming radiation should be considered because the risks are off the scale if nothing is done to try and keep the Earth alive..

Politically it's a race against time to alter the course of history really going uphill against human nature and environs.