Clouds to Hasten Global Temperature Rise
The direction of the cloud feedback has long been a source of uncetainty in projections of future temperature change, but a new study by Texas A&M scientist Andrew Dessler shows that as global temperatures rise, clouds will lead to further warming, acting as a positive feedback. The study, published in Science, looked at radiation data from the top of the atmosphere over the last decade coupled with climate data from NASA’s Modern Era Retrospective-Analysis for Research and Applications (MERRA) and the European Center for Medium-Range Weather Forecasts (ECMWF). Using these data, Dessler found that clouds will likely amplify warmth by trapping outgoing infrared radiation. This effect will be greater than any cooling that would occur as a result of clouds reflecting incoming solar radiation back to space. This study hold significance since previously the role of clouds in enhancing or reducing global warming was uncertain—climate skeptics often claim that clouds will act as a negative feedback and limit warming by reducing the albedo of the earth.