Environmental Erosion Research Journal

1- Introduction
Dust storms are prominent atmospheric phenomena involving the uplift of large volumes of dust particles from desert and arid surfaces into the atmosphere. The transport and dispersion of these particles over long distances are largely governed by prevailing meteorological conditions. This study investigates the dynamic and climatic drivers of dust storms in southwestern Iran. The research area includes selected synoptic stations located in the provinces of Khuzestan, Bushehr, Fars, and Kohgiluyeh and Boyer-Ahmad.
To analyze the spatiotemporal patterns of dust storms, hourly meteorological data, including sea level pressure, wind direction and speed, temperature, and relative humidity, were obtained from national synoptic stations and analyzed using statistical and synoptic-dynamic methods. In addition, reanalysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF) for the period 1985–2019 were employed to extract variables such as sea level pressure, geopotential height, zonal and meridional wind components, vertical velocity, streamlines, surface incoming shortwave radiation, and boundary layer height. Aerosol Optical Depth (AOD) data for the same period were acquired from the MODIS satellite platform.
Iran’s location within the global dry and semi-arid belt, coupled with its proximity to arid neighboring countries such as Saudi Arabia, Iraq, and Syria, regions characterized by limited vegetation cover, has led to the development of vast desert areas highly prone to dust emissions. These conditions, driven by low precipitation and high temperatures, create an environment conducive to frequent dust activity. Recurrent droughts, along with atmospheric turbulence and strong winds, further intensify dust uplift, particularly in southwestern Iran. Additionally, unsustainable land use practices and ongoing environmental degradation both within Iran and across its borders have contributed to the increasing frequency and severity of dust storms in the region.
Although numerous studies have investigated dust phenomena in Iran, and several have examined the mechanisms underlying dust storms in the western and southwestern regions, a comprehensive analysis of the dominant dynamic processes and regional atmospheric circulation patterns driving dust storm formation in southwestern Iran remains lacking. This study aims to address this gap by analyzing the regional atmospheric circulation and identifying the key dynamic and climatic mechanisms that contribute to the development and intensification of dust storms in the area.
2- Results
Trend analysis using the Mann-Kendall test revealed a statistically significant increase in the annual frequency of dust storms at most meteorological stations in southwestern Iran, with the exception of Dezful Airport, Omidiyeh Airport, Bushehr Coastal Shiraz, and Velar Airport in Bushehr. Sen’s slope estimator further confirmed significant upward trends at the 95% confidence level in stations such as Bostan, Abadan, Bandar Mahshahr, Omidiyeh, Aghajari, Dogonbadan, Khark Island, Zarghan, and Fasa. Notably, Dezful Airport and Bushehr Airport showed increases at the 95% and 99% confidence levels, respectively. Seasonal analysis for the period 1985–2019 also indicated consistent upward trends in dust storm occurrences across most stations and during all seasons.
3- Discussion & Conclusions
Synoptic and dynamic analyses revealed the presence of persistent low-pressure systems over Iran, Iraq, and Saudi Arabia during dust storm events, significantly influencing the weather patterns in southwestern Iran. Prominent low-pressure centers were identified at both the 850 hPa and 500 hPa atmospheric levels over Iran. Additionally, a jet stream core with wind speeds ranging from 40 to 60 m/s was observed at the 200 hPa level, facilitating the transport of dust from Iraq into southwestern Iran.
Dynamic analysis revealed significant vorticity at the 500 hPa level during dust storm events, indicating atmospheric rotational patterns conducive to dust uplift and long-range transport. MODIS satellite imagery, supported by HYSPLIT trajectory modeling, identified the primary sources of dust in Iraq, Sudan, and Saudi Arabia, with dust plumes intensifying while traveling toward southwestern Iran.
Examination of boundary layer dynamics showed that dust events were accompanied by an increase in boundary layer height, which strongly correlated with elevated AOD in the region. Additionally, analysis of surface-level incoming shortwave radiation demonstrated a marked decrease during dust storms, with higher dust concentrations causing more substantial reductions in solar radiation reaching the Earth's surface.
Overall, this study advances the understanding of the dynamic and climatic factors driving dust storm formation in southwestern Iran, providing valuable insights for improving forecasting and mitigating the environmental and health impacts of dust events in the region.