A new University of Washington study, with funding and satellite data from NASA and other agencies, finds a trend toward earlier sea ice melt in the spring and later ice growth in the fall across all 19 polar bear populations, which can negatively impact the feeding and breeding capabilities of the bears. The paper, to appear Sept. 14 in The Cryosphere, is the first to quantify the sea ice changes in each polar bear subpopulation across the entire Arctic region using metrics that are specifically relevant to polar bear biology.