Aerosol Science and Engineering

, Volume 3, Issue 4, pp 132–149 | Cite as

Influence of Atmospheric Dynamic Factors on Dust Aerosol Mobilization Over West Africa: Simulations from WRF-Chem

  • A. OluleyeEmail author
  • A. Folorunsho
Original Paper


Air pollution modeling has proved to be an effective tool in the description of atmospheric processes including pollutants source identification, transport, and dissipation on a regional scale where data are relatively sparse. This work employs the Weather Research Forecast with Chemistry option (WRF-Chem) coupled model to describe the dynamic atmospheric factors responsible for the dust diversion through very unusual path in the West African region on the 20th March, 2010. The simulation process was carried out between 15th and 25th March, 2010 to capture the dust activities during this unusual dust occurrence. Modeled aerosol optical depth (AOD) calculated by integration of aerosol extinction coefficient (Qext) on the vertical column was compared with observations from AERONET ground sun photometers at wavelength 440 nm. The results showed very strong correlation between the observed and the modeled AOD. Root-mean-square error (RMSE) of 0.46, 0.35, 0.37, and 3.09 over Banizoumbou, Dakar and IER_Cinzana, and Ilorin stations respectively, was obtained. Higher RMSE over Ilorin showed a restraint in capturing the AOD over Ilorin. A significant weakening of the Tropical Easterly Jet (TEJ) on the 19th March coupled with an abrupt wind regime change from easterly to westerly on the 20th day of the month at the African Easterly Jet (AEJ) level was seen to play an important role in the diversion of dust into the region. In addition, the development of stronger vertical wind shear within the troposphere atmospheric layer played a crucial role in the development and unusual transport of dust into the West African region during this period. This study provides concrete evidences of atmospheric processes influencing the transport of the Saharan dust, from the source region to other parts of West Africa.


Aerosol dust West Africa Atmospheric modeling WRF-Chem 



We had like to thank NCEP/NCAR for the free access to the precipitable water data provided by NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their website at, and also the Environmental Systems Science Centre for providing free access to the MSG-SEVIRI image used in this study. We also appreciate the AERONET team for proper calibration and maintenance of the freely assessed data available from The European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim data, Copernicus Climate Change Service (C3S) was accessed from


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Copyright information

© Institute of Earth Environment, Chinese Academy Sciences 2019

Authors and Affiliations

  1. 1.Department of Meteorology and Climate ScienceFederal University of TechnologyAkureNigeria

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