ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-10-5999-2010 Geoengineering by stratospheric SO<sub>2</sub> injection: results from the Met Office HadGEM2 climate model and comparison with the Goddard Institute for Space Studies ModelE Jones A. 1 Haywood J. 1 Boucher O. 1 Kravitz B. 2 Robock A. 2 Met Office Hadley Centre, Exeter, UK Department of Environmental Sciences, Rutgers University, New Brunswick, NJ, USA 05 07 2010 10 13 5999 6006 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/10/5999/2010/acp-10-5999-2010.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/5999/2010/acp-10-5999-2010.pdf

We examine the response of the Met Office Hadley Centre's HadGEM2-AO climate model to simulated geoengineering by continuous injection of SO<sub>2</sub> into the lower stratosphere, and compare the results with those from the Goddard Institute for Space Studies ModelE. Despite the differences between the models, we find a broadly similar geographic distribution of the response to geoengineering in both models in terms of near-surface air temperature and mean June–August precipitation. The simulations also suggest that significant changes in regional climate would be experienced even if geoengineering was successful in maintaining global-mean temperature near current values, and both models indicate rapid warming if geoengineering is not sustained.

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