In this video, adapted from KUAC-TV and the Geophysical Institute at the University of Alaska, Fairbanks, viewers learn how one-celled organisms in permafrost may be contributing to greenhouse gas levels and global warming.

This is a photo essay linked to a New York Times story about climate-related stressors on forests -- including mountain pine beetles, forest fires, forest clearance, and ice storms -- and the importance of protecting forests as an important carbon sink.

This article and slide show from the New York Times, features several scientists from the University of Alaska, Fairbanks, who study the effects of thawing permafrost in Alaska.