Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder

Climate Change Threatens Polar Bears

Global warming threatens collapse of most polar bear populations by end of century

A new U of T Scarborough-led study with CIRES coauthors finds that we can expect the collapse of most polar bear populations by the end of the century if global warming continues at the current pace.

The Nature Climate Change study is the first to offer timelines showing how Arctic sea ice loss will impact the ability of polar bears to reproduce and survive since they will have to endure longer periods without food.

“The challenge is that Arctic sea ice will keep disappearing as the world continues to warm,” says lead author Péter Molnár, an assistant professor in the Department of Biological Sciences at U of T Scarborough.

“This means polar bears everywhere will face longer periods without food, and this will affect their ability to reproduce, survive and persist as healthy populations.”   

Most of the polar bear diet consists of seals, which they can only catch on sea ice. But as the ice continues to melt the bears have less time to hunt, which means eating less, putting on less weight, and then fasting longer as a consequence. 

This press release was written by U of T Scarborough communications. Read the full story here.

CIRES is a partnership of NOAA and CU Boulder.


Péter K. Molnár
University of Toronto Scarborough, lead author
Jen Kay
CIRES fellow, coauthor
Don Campbell
U of T Scarborough Communciations