Black carbon and atmospheric feedbacks

摘要

Black carbon, often referred to as soot, is emitted during the incomplete combustion of fossil fuels, biofuels or wood. In contrast to other particulates emitted into the atmosphere by human activities, black carbon absorbs sunlight efficiently. This absorption leads to local heating of the atmosphere, warming the planet. Black carbon has received particular interest recently in the context of changes in climate policy. It remains in the atmosphere for only a few days, so cutting black-carbon emissions may be a viable way to reduce global warming over the next few decades, alongside measures to mitigate changes in the emissions of carbon dioxide. Such actions need to be supported by a good understanding and prediction of the climate role of black carbon. Writing in the Journal of Climate, Sand et al. report climate simulations that provide insights into these issues. The results highlight challenges for upcoming international initiatives aimed at better understanding how the climate responds to changes in the composition of the atmosphere.