National Public Radio: As they die and decompose, trees and soil in the Amazon rainforest have traditionally absorbed more carbon dioxide from the atmosphere than they’ve emitted. But it turns out that during a major drought in 2005, the Amazon put more carbon into the atmosphere than it soaked up. That worries scientists, who say that the Amazon’s role as a “carbon sink” that sucks global-warming carbon dioxide out of the atmosphere may be compromised. The Amazon is the largest rainforest in the …