The Bowhead has survived a lot.  Could it survive a 15 C rise in the Arctic? 
 On the Bowhead, or Greenland Right Whale see also Thin Ice and Hunters and hunted.
 See Richard Betts here. The signs are already bad for Walruses. See: Walruses Suffer Substantial Losses as Sea Ice Erodes
P.S. (added Oct 5): Could Gray whales be one of the species to move into Arctic waters in place of the Bowheads (assuming there to be sufficient food available for them in the newly warming waters)? In Watching whales watching us, Charles Siebert reports the biologist Steven Swartz saying, "they’re expanding their feeding grounds all along their migration route and in the north, and some are even staying in Arctic water over the winter..."
P.P.S (added Oct 6): 'Arctic seas turn to acid, putting vital food chain at risk.'