A massive arctic thaw is unleashing carbon frozen for thousands of years

A sweeping new study reveals that as Arctic permafrost thaws, it is dramatically reshaping rivers and releasing vast amounts of ancient carbon that had been locked away for thousands of years. By analyzing decades of high-resolution data across northern Alaska, scientists found that runoff is increasing, rivers are carrying more dissolved carbon, and the thawing season is stretching further into the fall. This carbon eventually reaches the ocean, where some of it turns into carbon dioxide, inten...