Scientists have long known that Arctic climate change is bad news for bears, but University of Washington researchers quantify just how bad it is in a study published today.
The study in The Cryosphere, a journal of the European Geosciences Union, is said to be the first to assess the impact of sea ice changes for 19 different populations of polar bears across the entire Arctic region, using the metrics that are most relevant to polar bear biology.
The analysis draws upon 35 years’ worth of satellite data showing daily sea-ice concentration in the Arctic. There’s a consistent trend toward earlier thawing in the spring, and later freezing in the winter. Between 1979 and 2014, the total number of ice-covered days declined at the rate of 7 to 19 days per decade. Over the course of 35 years, seven weeks of good sea-ice habitat were lost.