Abstract
Dust storms have direct and indirect effects on the climate and the environment under their influence. During the last two decades, due to climate changes and land use changes in the west and southwest of Iran, dust storms with precipitation have been observed, which certainly greatly impact the cloud structure and subsequent precipitation in this region. This research aims to identify the origin of dust storms and investigate the effects of these storms on the physical structure of clouds in rainy conditions and unstable atmospheres in the study area. This research used thematic maps, the HYSPLIT model, and satellite images to identify the source of these types of storms. Also, SIVIRI sensor images and dust data from the CAMS global reanalysis EAC4 have been used to investigate the effects of dust on the cloud structure. Based on model tracking and satellite images, five regions, including the Nafud desert and Rub al-Khali in Saudi Arabia, desert regions of North East Africa, western regions of Syria, and western Iraq, were identified as the most important source of this phenomenon. Also, the effects of dust on cloud structure showed a strong positive correlation between the amount of dust and the parameters of optical depth and liquid water path, at a significant level of 95% in the sample of heavy rains. There is no significant correlation in the relationship between other parameters of cloud structure in the event of heavy precipitation. Also, the results showed no significant relationship between the amount of dust and cloud parameters in light rain. Identifying the source areas and routes of dust storms, as well as investigating the effects of dust on the structure of clouds, will improve our understanding of the mechanisms and effects of dust storms on the climate and environment of the region.