Author(s)

Bado Nébon^1,2*, Mamadou Simina Dramé², Saidou Moustapha Sall², Korgo Bruno¹, Demba Ndao Niang², Kieno P. Florent¹, Bathiebo Dieudonné Joseph¹

¹Laboratoire d’Energies Thermiques Renouvelables (LETRE), Université Ouaga I Pr Joseph KI ZERBO, Ouagadougou, Burkina Faso.
²Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon-Fongang, Université Cheikh Anta DIOP, Dakar, Sénégal.

This paper deals with the characterization of aerosols in the Sahelian zone, particularly in Burkina Faso based on MODIS observations and in situ measurements of the AERONET network on the Ouagadougou site (12.2°N, 1.4°W). Thus, a seasonal spatial distribution of aerosols made over the period from 2001 to 2016 gives a very great variability of aerosols in Burkina Faso, whose maxima are encountered in Spring, characterized by winds from the North East. This seasonality of aerosols is also shown by the annual cycles of optical, radiative and microphysical parameters measured by AERONET between 1999 and 2006. Moreover, an analysis of these parameters shows the prevalence of mineral dusts characterized by low values of the Angstrom coefficient (α_440-870 < 0.5) associated with the maxima of AOT with high intensity in March. These dusts are confirmed by their scattering nature (SSA > 0.9) and the cooling noticed in the bottom of atmosphere (BOA) and at the top of the atmosphere (TOA). Also, the climatology of the volume size distribution of aerosols shows a very great variability of particles in terms of size influenced by the thin and coarse pattern where most sizes are between 1 and 10 μm.

Aerosol, AERONET, MODIS, Microphysical and Optical Properties, Radiative Forcing

Nébon, B. , Dramé, M. , Sall, S. , Bruno, K. , Niang, D. , Florent, K. and Joseph, B. (2019) Intra-Seasonal and Annual Variation of Aerosols and Their Radiative Impact in the Sahelian Zone of Burkina Faso. Atmospheric and Climate Sciences, 9, 62-74. doi: 10.4236/acs.2019.91004.