ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-10-6901-2010 Relationships between mineral dust and cloud properties in the West African Sahel Klüser L. 1 2 Holzer-Popp T. 1 German Aerospace Center (DLR), German Remote Sensing Datacenter (DFD), Wessling, Germany University of Augsburg, Institute of Physics, Augsburg, Germany 26 07 2010 10 14 6901 6915 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/10/6901/2010/acp-10-6901-2010.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/6901/2010/acp-10-6901-2010.pdf

Aerosol cloud interactions are known to be of great importance to many parts of the climate system. Five years of observations from three different satellites (Aqua, ENVISAT and Meteosat Second Generation) are used to statistically analyse the relationship of mineral dust aerosol, separated from other aerosol species, with monsoon season cloud state in the West African Sahel domain. Additionally, observations of the Tropical Rainfall Measuring Mission are used for discrimination of dry and wet seasons. The aerosol-cloud-interactions are analysed separately by season and air mass in order to minimise spurious correlations with meteorological conditions. The detailed analysis uncovers different counteracting relationships of the mineral dust aerosol with the cloud state, which is also evident from an analysis of the spatial distribution patterns of cloud properties changes with dust activity. The aerosol-cloud relationships found from the analysis of this multiple year dataset are mainly consistent with the hypothesis of a suppression of convective activity, but also indications of lifetime enhancement and thus increased cloud cover and convective intensity are found in some subsets.

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