Οptical and microphysical properties of Saharan and Saudi Arabian desert based on AERONET data products

The study investigates possible differences between the Saharan and Saudi Arabian deserts' dust particles based on AERONET network. Our results shows that while particle depolarization ratio values at 440 nm were similar for both regions, the Saudi Arabian lidar ratio (at 440 nm) was determined to be 53 ± 7 sr, much lower than the Saharan lidar ratio at the same wavelength that was found equal to 66 ± 10 sr. Our findings are in consistent with earlier studies based on AERONET products but they do not agree with lidar observations. We found significantly larger lidar ratios at 440 nm both for Arabian dust (difference of 15 sr) and Saharan dust (difference of 13 sr) compared to lidar observations. These differences are smaller for 532 nm. Reliable conversion factors between aerosol optical thickness and column-integrated particle size distribution based on AERONET photometer observations are also for Saharan and Saudi Arabian dust particles.