The fate of thawing Arctic soils may have profound impacts far from the North pole, as more than a trillion tons of carbon are locked in frozen permafrost there. Eli Kintisch traveled to Cherskiy, Russia, and Barrow, Alaska, to investigate. Here he explains how the thawing soil is already affecting the way people store food and the likelihood of forest fire. He also profiles a scientist with a radical concept on preserving the permafrost to prevent release of a massive new carbon source.