Document Type : Research Paper
Authors
1
Ph.D. in Climatology, Lorestan University, Khorramabad, Iran
2
Associate Professor, Department of Climatology, Lorestan University, Iran
3
Meteorological Expert of East Azarbaijan, Tabriz
4
Assistant Professor, Department of Climatology, Lorestan University, Khorramabad, Iran
Abstract
Dust storms are one of the environmental problems that affect human health, air quality and the economies of the countries of the world on a large scale. The purpose of this study is the identification of the source of dust entering the east of Iran and tracking its route. Initially, using horizontal visibility data, satellite imagery, Dust Aerosol Index related to the OMPS, and AOD, the dust storms detected from 2000 until 2018 were examined. Then, the pressure data, wind direction, wind speed, geopotential heights and jet streams at various atmospheric levels were obtained from the European Meteorological Center (ECMWF) with a spatial resolution of 0.25 * 0.25. Finally, the HYSPLTE model was used to determine the origin of the storm formation. The results showed that 46.67% of the region's dust storms were local, 33.33% were transmitted, and 20% occurred concurrently. The satellite studies of the transmitted dust storms showed that they formed in southern Iraq and central Saudi Arabia and then moved to the studied area, which was compared with the results of the model. Synoptic studies also showed the synoptic origin of the storms and their being structured by northern winds, where jet streams and polar jet streams converge to provide favorable conditions for dust storms. The study of the storms formed at the site indicated that severe storms in the area could be due to the pressure gradient, cyclones and jet stream interference in the area.
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