Black carbon plays a much larger role in climate change than previously thought, according to a study published last week in the Journal of Geophysical Research. Soot, long known to be atmospherically destructive, is second only to carbon dioxide as the largest cause of climate change, and its heat trapping power is about twice the estimate made by  the Intergovernmental Panel on Climate Change in 2007. Rising from sources as varied as tailpipes and forest fires, the effect of soot on the atmosphere is broad and strong. "The more we study it, the more mechanisms people find," said a co-author of the study. Scientists calculated how much energy was being stored in the atmosphere due to black carbon, finding that the 1.1 extra watts per square meter of the earth's surface was second only to carbon dioxide's 1.56. The findings make soot reduction an attractive option for dealing with climate change, as black carbon washes quickly out of the atmosphere. For the full story, see http://e360.yale.edu/feature/carl_zimmer_black_carbon_and_global_warming_worse_than_thought/2611/.