Remote sensing of desert dust in Kuwait

Ground-based measurements of aerosol optical thickness (AOT) and water vapor were conducted in Kuwait City from September 1998 to December 1999. Time series plots of the 675 nm AOT (7-675) and water vapor measurements are presented along side the derived atmospheric turbidity (/?) and the Angstrom wavelength exponent (a). The values of AOT and the atmospheric turbidity were generally high throughout the year (r, j3 0.2). The values of AOT, p and wind speed were enhanced during the 6-month interval from March-August 1999, while those of a were the lowest. The contribution from the southern winds passing over the Arabian Gulf was least during this 6-month period, indicating that most of the aerosols particles during that interval were large dust particles. The time series plot of turbidity data set is separated into two components: one component represents days with background turbidity and the other represents days with high turbidity. Each component was analyzed separately in conjunction with various weather parameters, such as wind speed, direction and weather phenomena. We obtained 36 days with high values of turbidity (f3 0.44) during the study period. These high /3 values were mainly due to the movement of moderate to high speed winds blowing over the country from Iraqi desert in the north-west direction carrying mineral dust particles of various sizes. However, some of these days had high f3 values due to high concentrations of water vapor carried inland by wind passing over the Arabian Gulf