Investigation of spatio-temporal changes of dust storms and its relation to climatic factors in Khuzestan Province Iran

Dust is one of the major crises in the Middle East. In recent years, the frequency and intensity of this crisis in the region has increased and this has increased the need to study this phenomenon. In this article, we have studied the temporal and spatial changes of the dust storm phenomenon in Iran, Khuzestan (south-west) in the period 2000 to 2018. For this purpose, ground dust data and horizontal visibility and (Aerosol Optical Depth( data of MODIS satellite have been used. The AOD Optical Visibility Index has been declining from 2003 to 2007 and then increasing again. In general, we can see a gradual but increasing trend in the AOD index in the study area, from an average of 0.35 at the beginning of the period to nearly 0.6 at the end of the period, which indicates the predominance of dust storms in the region. The relationship between dust and climatic parameters was also examined. In terms of external storms, precipitation had a significant (P <0.001) and negative effect. This means that on days when there is less rain, the horizontal visibility index decreases and more dust storms were formed. In terms of domestic storms, only the wind direction had a significant direct effect (P <0.05), which means that some directions had higher dust storm frequencies. Finally, it can be concluded that the trend of domestic and foreign dust storms is increasing. The frequency of their occurrence is also increasing and with the decrease of regional rainfall due to climate change, we should expect more severe storms in the near future. For this reason, it is necessary for the authorities to act as soon as possible in controlling the internal dust centers, and to provide the ground for controlling the regional centers through regional consultations.