Impact of Sahara dust aerosols on regional climate over the Iberian Peninsula with RegCM4

Abstract

The objective of our study is to investigate the impact of dust aerosols and future changes on regional climate over the Iberian Peninsula, where dust events frequently occur because Sahara desert is very close. The climatic effects of dust aerosols are investigated using the last version of the Regional Climate Model system RegCM4 with a spatial resolution of 20 Km and 18 sigma vertical levels. In relation to the first simulation, initial and lateral boundary conditions are created using reanalysis data. In the second experiment, there is two simulations for the 2050 year with boundary conditions from the CCM3 global model, one containing concentration of dust aerosols and the other omitting dust. The effects of Sahara dust events on ground temperatures and precipitations are presented in this work. The results indicated that dust aerosols generally produced negative radiative forcing at the top of the atmosphere over most areas.