19 November, 2012

Turn down the heat: why a 4°C warmer world must be avoided

Authors

Hans Joachim Schellnhuber, William Hare, Olivia Serdeczny, Sophie Adams, Dim Coumou, Katja Frieler, Maria Martin, Ilona M. Otto, Mahé Perrette, Alexander Robinson, Marcia Rocha, Michiel Schaeffer, Jacob Schewe, Xiaoxi Wang, Lila Warszawski.

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This report provides a snapshot of recent scientific literature and new analyses of likely impacts and risks that would be associated with a 4°C warming within this century. It is a rigorous attempt to outline a range of risks, focusing on developing countries and especially the poor.

A 4°C world would be one of unprecedented heat waves, severe drought, and major floods in many regions, with serious impacts on ecosystems and associated services. But with action, a 4°C world can be avoided and we can likely hold warming below 2°C.

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