Arctic carbon tipping point reached?

The Arctic tundra is now releasing more carbon dioxide into the atmosphere than it stores. Host Carolyn Beeler speaks with Twila Moon, deputy director of science at the National Snow and Ice Data Center. She is the lead editor of this year’s Arctic Report Card, released yesterday, which shows how rising temperatures are forcing the Arctic’s plants, wildlife and the people that depend on them to rapidly adapt to a warmer, wetter and less certain world.