Dust Detection and Mapping in Kermanshah Province Using MODIS Satellite Imagery

The aim of this study was to investigate the status of dust storms in Kermanshah province، Iran، using climatic and remote sensing data. Dusty days recorded at 12 meteorological stations were obtained and analyzed at monthly and yearly scales from 1990 to 2011 and then the relationship of visibility data (<1000m) with other climatic parameters including temperature، relative humidity، rainfall، maximum wind speed and direction were evaluated using multivariable linear regression. Also، two important dust events on 15/9/2008 and 5/7/2009 were selected and then MODIS level 1B satellite data was converted to brightness temperature data with MODIS conversion Toolkit and then three main dust indices including Ackerman، Miller and TDI were used to map dust distribution in the study area. Results showed that the number of dusty days with a visibility less than 1000 m reached 71، 53 and 112 days in Kermanshah، Islamabadgharb and Sarepolezahab stations، respectively. The maximum dusty days (20 days/year) occurred in Somar station in the west of the Kermanshah province، which is the nearest station to Iraq. According to the regression analysis، the visibility data had the highest relationship (R2>0. 77) with rainfall، wind direction and speed parameters. The results of MODIS dust mapping showed that the performance of dust indices differs from one event to another. According to dust classified maps and visibility data، the Ackerman index performed best، followed by TDI and Miller indices.