ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-12-10887-2012 Sea-spray geoengineering in the HadGEM2-ES earth-system model: radiative impact and climate response Jones A. 1 Haywood J. M. 1 2 Met Office Hadley Centre, Exeter, UK College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK 16 11 2012 12 22 10887 10898 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/12/10887/2012/acp-12-10887-2012.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/12/10887/2012/acp-12-10887-2012.pdf

The radiative impact and climate effects of geoengineering using sea-spray aerosols have been investigated in the HadGEM2-ES Earth system model using a fully prognostic treatment of the sea-spray aerosols and also including their direct radiative effect. Two different emission patterns were considered, one to maximise the direct effect in clear skies, the other to maximise the indirect effects of the sea-spray on low clouds; in both cases the emissions were limited to 10% of the ocean area. While the direct effect was found to be significant, the indirect effects on clouds were much more effective in reducing global mean temperature as well as having less of an impact on global mean precipitation per unit temperature reduction. The impact on the distribution of precipitation was found to be similar in character, but less in degree, to that simulated by a previous study using a much simpler treatment of this geoengineering process.

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