Dust Optical and Microphysical Properties of Saharan and Saudi Arabian Deserts Distributed in Europe Based on AERONET Data Products

This study investigates the spatial distribution of optical and microphysical dust properties in Europe and possible differences between the Saharan and Saudi Arabian deserts’ dust particles based on the AERONET network. Data were collected within the period from 2001 to 2018 from 16 different stations. Pure dust conditions were identified. 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, which was found to be 66 ± 10 sr. Particle depolarization ratio values at 440 nm were similar for both regions. Although our findings are consistent with earlier studies based on AERONET products, 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 at 532 nm. Differences at both 440 and 532 nm between AERONET and lidar observations were on the order of 5 sr for Arabian dust and even smaller (order of 2 sr) for Saharan dust.