Statistical analysis of occurrence frequency of dust storms in Yazd province and its modeling based on climatic elements and vegetation cover

Introduction Dust storms as one of the environmental hazards of the arid regions of the globe, including the southern, southwestern, eastern and central parts of Iran, has caused many environmental problems that confirm the need for studying and crisis managing its in scientific and executive congresses. Therefore, the present study attempts to evaluate the effects of climate elements on temperature, precipitation, humidity, evapotranspiration and vegetation index on the frequency of dust storms in Yazd province during the period of 5 years (2009-2014).   Data and Methodology So, after determining the synoptic stations of the area, the dust data were extracted based on the code of the present weather phenomena and the values of the climatic elements. In the next step, their spatial zonation was determined through the interpolation method. Then, using the MODIS images, EVI index data were calculated according to the principle of time matching. Finally, a variety of simple and multiple regression models were fitted to estimate the occurrence frequency of dust, and the most appropriate relationships with higher preference values were reported.   Findings and Conclusions The results showed that there was a significant relationship between the total dust with evapotranspiration and relative humidity with a R square of 0.973 and 0.614 and the standard deviation of 24.104 and 92.477 at sig. level of 99% and 95%. Also, there is the maximum significant relation between external dust with evapotranspiration and relative humidity with a R square 0.968 and 0.621, and the standard deviation was estimated to be 0.173 and 75.427 at sig. level of 99% and 95%, respectively. Internal dusts with evapotranspiration and maximum temperature with a R square of 0.770 and 0.377 and standard deviation of 15.1751 and 64.22 have a significant relationship with sig. level of 95%. The results of the total, external and internal dust storms with climatic elements and vegetation cover showed a significant correlation with the R square of 0.994, 0.988 and 0.956 and the standard error of estimation of 18.13713, 24.2555551 and 10.49989 at sig. level of 99% and 95%, respectively, which indicates the systematic function of climatic elements and vegetation cover in the occurrence of dust.