Long-term Aerosol Monitoring at the Western Arabian Peninsula and Red Sea Coast

The Arabian Peninsula is one of the World’s largest dust source regions. It is also affected by natural and anthropogenic pollution of African, Asian, and European origin. As the Arabian Peninsula is highly under-sampled, we have since 2012 established and maintained aerosol monitoring sites at King Abdullah University of Science and Technology (KAUST), as well as in the North-Western part of the Arabian Peninsula, and the Red Sea coast. The sites incorporate the following instrumentation. Two CIMEL sun photometers operational since 2012 as a part of the NASA Aerosol Robotic NETwork (AERONET), providing aerosol optical depth (AOD) and aerosol parameters, reporting data to the NASA Goddard website (http://aeronet.gsfc.nasa.gov/cgi-bin/type_piece_of_map_opera_v2_new). The AOD distribution over the Red Sea is measured during KAUST Red Sea cruises using a hand-held sun photometer (Microtops II). The data are reported to the NASA Maritime Network (http://aeronet.gsfc.nasa.gov/new_web/maritime_aerosol_network.html). Vertical Distribution of aerosols is sampled using the Micro Pulse Lidar (MPL) operating as a part of the NASA MPLNET (http://kimura.gsfc.nasa.gov/site--‐page?site=Kaust). We measure aerosol deposition rates on a monthly basis using passive samplers in different several locations (KAUST, 2015-2023; Al Wajh Lagoon, 2021-2022; DUBA & Tabuk,2022 -2023) and conducted a mineralogical analysis of deposited aerosols by X-ray diffractometry (XRD) and measured particle size distributions using Mastersizer3000.

Our objective in this study is to conduct an in-depth analysis of the combined effects of natural and anthropogenic pollution on air quality, climate, and application of renewable energy across the Arabian Peninsula, providing a scientific foundation for model calibration in this region. Here we report on the data sets collected in 2012- 2023:

• KAUST campus site: Six dust deposition samplers, AERONET, MPL
• Al Wajh Lagoon site: Nine dust deposition samplers
• Duba site: Two dust deposition samplers
• Tabuk site: Two dust deposition samplers

In our group’s research at KAUST, these data sets, in combination with the available satellite observations, were integrated into the meteorology-chemistry-aerosol model, WRF-Chem, to quantify the aerosol environmental impacts and support environmental decision-making in the region.