A Simulated Climatology of North African Dust and its Impact on Meteorological Parameters Using WRF-CHEM Model

The climatic effects of dust outbreaks in North Africa have been simulated using the weather research and forecasting model coupled with chemistry module (WRF-CHEM). This work presents the second simulation (climate dust simulation) of a series of simulations (first was climate simulation (2m Temperature and Precipitation) and the third will be aerosols climate simulation) with WRF-CHEM model over a large domain covering most of the African continent. The Ozone Monitoring Instrument (OMI) absorbing Aerosol Index (AI) is used to indicate the presence of elevated absorbing aerosol (such as desert dust) in the earth's atmosphere. For the distribution of dust concentration, the WRF-CHEM model captured the distribution of dust concentration over the studied area according to the OMI absorbing aerosol index AI. For the impact of dust on the meteorological parameters we got the seasonal differences (DUSTRUN-NODUST) for 2m temperature, precipitation, outgoing longwave radiation (OLR), and cloud fraction, the climate simulation including dust generally reduces the precipitation in the normal rainfall band over North Africa, as well as overall seasons due to the dusty case, OLR is reduced over the mostly cloudy North Africa region, while the cloud fraction shows decreases across North Africa and the Atlantic with an increase to the east, and the differences in T2m varied from season to season. The increase in precipitation is associated with increased convection in that region due to the heating of the air column by dust particles, as well as produces more cooling at the cloud top.