Investigating the Relationship Between Dust Storm Index and Some Climatic Parameters, Vegetation Index and Land Form Types (Yazd-Ardakan Plain)

Dust is one of the most important atmospheric phenomena, which has attracted the attention of many scientists as an emergent phenomenon. Current research has studied trend of the number of dust days and its relation to climatic parameters and vegetation index from 2005 to 2017 in the Yazd-Ardakan plain. The DSI was computed for the two meteorological stations at Yazd and Meybod. By classifying the two Landsat 7 and 8 satellite images, the land form/cover maps, including agricultural lands, urban, mantled pediments, covered pediment and erg have been prepared. The NDVI layer was then computed in two classes for the Landsat 7 and 8 satellites. The class area was calculated for all levels of the region and also within two buffers of 10 and 20 km at the center of stations Yazd and Meybod. The relationship between the climatic parameters, including annual average temperature, annual average precipitation and annual average relative humidity, was then calculated. Finally, the relationship between dust index and land form types, NDVI layer and climatic parameters has been investigated. The results showed that the relationship between the DSI and the erg type is direct, but there is an inverse relation with the mantled pediments, covered pediment and agricultural land. Based on the results obtained, urban lands have little effect on the dust storm index. By comparing the DSI with the NDVI, with the increase in the region's dust storm index, the NDVI values for all levels decreased. By comparing the DSI with the climatic parameters, with the decrease in annual average precipitation and relative humidity and the increase in annual average temperature, the dust Storm index increased.