By Donna Hauser, Harry Stern and Kristin Laidre
Americans often associate fall with football and raking leaves, but in the Arctic this season is about ice. Every year, floating sea ice in the Arctic thins and melts in spring and summer, then thickens and expands in fall and winter.
As climate change warms the Arctic, its sea ice cover is declining. This year scientists estimate that the Arctic sea ice minimum in late September covered 1.77 million square miles, tying the sixth lowest summertime minimum on record.
Footage captured by aerial drones as part of a narwhal research camp in Tremblay Sound, Nunavut, is giving biologists new insights into the behavior of one of the world's most mysterious whales.