INVESTIGATION OF DUST SCHEMES IN THE MODEL WRF/CHEM

Introduction : In this study, the dust schemes implemented in the model WRF/Chem have been investigated for a severe dust storm as a case study over the Middle East. Materials and methods : There are three main dust schemes in the model WRF/Chem, which are named GOCART, AFWA, and UoC. All of these dust schemes use the same dust source function, based on a topographical method, which plays a crucial role in the simulation of dust emission from the ground. Results : The results of model for dust distribution are validated by the EUMETSAT MSG dust product, and furthermore the capabilities of the model are investigated by comparing the model output with the measured PM 10 concentrations of 3 air pollution monitoring stations. The AFWA dust scheme showed better capability in the simulation of dust behavior considering dust distribution. Although the GOCART dust scheme shows a remarkable coincidence between modeled and measured dust concentration, its results are with a considerable overestimation over the study domain. The UOC dust scheme, except Kerman station, shows a drastic underestimation in dust concentration as well as dust distribution. Conclusions : The results show appropriate estimates of dust distribution and its movement through east. The model WRF/Chem as a state of the art numerical model could be applied in the operational forecast systems for the hazardous