ACPD Atmospheric Chemistry and Physics Discussions ACPD Atmos. Chem. Phys. Discuss. 1680-7375 Göttingen, Germany 10.5194/acpd-10-3053-2010 Impacts of dust on West African climate during 2005 and 2006 Camara M. 1 4 Jenkins G. 2 Konare A. 3 Département de Physique, Université de Ziguinchor, BP 523, Ziguinchor, Senegal Physics and astronomy department, Howard University, DC, 20059, USA Université de Cocody, Abidjan 22, BP 582, Côte d'Ivoire Laboratoire de Physique de l'atmosphère – SF, BP 5085 Dakar-Fann, Senegal 05 02 2010 10 2 3053 3086 Copyright: © 2010 M. Camara et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/preprints/10/3053/2010/acpd-10-3053-2010.html The full text article is available as a PDF file from https://acp.copernicus.org/preprints/10/3053/2010/acpd-10-3053-2010.pdf

The aim of this study is to understand the impacts of Saharan dust outbreaks on West African climate using a 3-dimensional, hydrostatic, sigma vertical coordinate regional climate model (RegCM). We performed a simulation with the non aerosol version of the model (control case) followed by another simulation using the desert dust module (dust case) implemented in RegCM which includes emission, transport, gravitational settling, wet and dry removal and calculation of dust optical properties for 2005 and 2006. Dynamic and thermodynamic parameters obtained from both versions of the model are intercompared and validated with NCEP/NCAR reanalysis, African Monsoon Multidisciplinary Analysis (AMMA) program data and the Global Precipitation Climatology Project (GPCP) rainfall products. The spatial and temporal distribution of the Aerosol optical depth derived from the desert dust run is compared to available observed aerosol data such as the Aerosol Robotic Network (AERONET) program and satellites data. <br><br> Using radiosounding data and RegCM outputs, a case study of a strong dust outbreak showed the presence of a stable environment at Dakar, Sal and Nouadhibou stations.

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