Numerical Simulation of a Severe Dust Storm over Ahvaz Using the HYSPLIT Model

Abstract

In this paper, numerical simulation of a severe dust storm over Ahvaz on 16–18 June 2016 was performed using the HYSPLIT. To that end, the HYSPLIT model has been configured for different model setups to determine the most desirable suite of parameters to represent the measured concentrations better. Among several model parameters, meteorological dataset (GDAS1.0 and GDAS0.5), friction velocity (P10F) and particle numbers (NumPar) were detected as the most influential parameters on the simulation results. Accordingly, with P10F = 0.6, NumPar = 5000, and GDAS1.0 configurations, the model has reproduced the most precise results, and the correlation coefficient between the measured and the simulated PM10 concentration was as high as 0.9. Since the threshold friction velocity influences the results significantly, it is suggested to calculate the P10F coefficient for each distinct dust storm meticulously. Once the best model parameters have been obtained, the HYSPLIT has been run for 33 possible sources separately to estimate the contribution from each sub-region to the levels of the measured PM10 concentration of Ahvaz during 16–18 June 2016. According to the results, central Iraq, northern Syria, western Iraq, and Al-Hawzieh/Al-Azim wetland account for 71, 19, 6, and 4%, respectively.