Analysis of the effect of climatic parameters on the number of dusty days in Ghazvin province

The purpose of this study is to evaluate the effect of climate change on the occurrence of dust in Ghazvin province. In order to study climate fluctuations, average rainfall parameters, relative humidity, potential evapotranspiration, temperature, relative humidity, average wind speed and wind speeds greater than 6 m / s in the period 2006-2016 were considered and the number of dusty days was extracted according to the dust phenomenon codes (06 to 09, 30 to 35, and 98)and calculated on a monthly, seasonal and annual scales. The trend of changes in climatic parameters and the number of dusty days were investigated using Mann-Kendall test and the relationship them between was investigated using Pearson correlation coefficient. The results showed that wind speeds of more than 6 m / s in most study scales had a significant decreasing trend (Z> -1.96). A similar trend was observed for mean air temperature and potential evapotranspiration in October. The trend of changes in dusty days was shown to be significant for internal events in summer and for extranal events in spring. However, no significant changes were observed in other parameters. The results also showed that local dusty days with a slope of 0.08 and days with extenal scource dust with a slope of 0.68 in the statistical period have increased. Pearson correlation analysis showed that there was a strong and significant relationship between the increase in mean maximum temperature with the number of days with local dust in winter and also between the average speed of spring surface winds with the number of dusty days during this period (r=0.67; p-value≤ 0.0.5).