Identifying trajectories and sources of dust events in Yazd province using HYSPLIT model and remote sensing data

Dust storm is one of the destructive weather phenomena that strongly affects regions with arid and semiarid climates like Yazd province. This phenomenon leads to many losses, including environmental, socio-economic, human health, climate and microclimate problems. Accurate spatial and temporal monitoring of dust can help identify the trajectories and sources of this atmospheric hazard and play a vital role in management and reduction of possible damages of storm. In the present study, three examples of dust storms that occurred in 2022 in Yazd province were analyzed. When the visibility is less than 3.5 km and one of the codes 06 to 09 or 30 to 35 is reported, it is considered as an effective dust storm. The lagrangian HYSPLIT model was used to identify the trajectories of dust transfer to Yazd province. The results of this model indicate that dust masses travel three main pathways to reach Yazd province: southwest, west-northwest, and northeast. In order to investigate the spatial distribution of dust and also to identify dust sources more accurately, the aerosol optical depth data based on remote sensing, the MOD04/MYD04_L2 product and also the MOD08_D3 product, were used. These images showed that the external sources of dust are the large deserts of Iraq, Syria, the Arabian Peninsula, and the desert of Turkmenistan, and the internal source of dust is the desert areas located in the provinces of Semnan, Isfahan in the northeast of Yazd province. In addition, the Gavkhoni wetland in the northwest of the study area acts as an intensifier of the dust transferred from the western borders of the country. Also, the results obtained from the satellite data and the HYSPLIT model are consistent with each other.