Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Atmos. Chem. Phys., 17, 11467-11490, 2017
https://doi.org/10.5194/acp-17-11467-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
27 Sep 2017
Physical and chemical properties of deposited airborne particulates over the Arabian Red Sea coastal plain
Johann P. Engelbrecht1,2, Georgiy Stenchikov1, P. Jish Prakash1, Traci Lersch3, Anatolii Anisimov1, and Illia Shevchenko1 1King Abdullah University of Science and Technology (KAUST), Physical Science and Engineering Division (PSE), Thuwal, 23955-6900, Saudi Arabia
2Desert Research Institute (DRI), Reno, Nevada 89512-1095, USA
3RJ Lee Group Inc., Monroeville, Pennsylvania 15146, USA
Abstract. Mineral dust is the most abundant aerosol, having a profound impact on the global energy budget. This research continues our previous studies performed on surface soils in the Arabian Peninsula, focusing on the mineralogical, physical and chemical composition of dust deposits from the atmosphere at the Arabian Red Sea coast. For this purpose, aerosols deposited from the atmosphere are collected during 2015 at six sites on the campus of the King Abdullah University of Science and Technology (KAUST) situated on the Red Sea coastal plain of Saudi Arabia and subjected to the same chemical and mineralogical analysis we conducted on soil samples. Frisbee deposition samplers with foam inserts were used to collect dust and other deposits, for the period December 2014 to December 2015. The average deposition rate measured at KAUST for this period was 14 g m−2 per month, with lowest values in winter and increased deposition rates in August to October. The particle size distributions provide assessments of  < 10 and  < 2.5 µm dust deposition rates, and it is suggested that these represent proxies for PM10 (coarse) and PM2. 5 (fine) particle size fractions in the dust deposits.

X-ray diffraction (XRD) analysis of a subset of samples confirms variable amounts of quartz, feldspars, micas, and halite, with lesser amounts of gypsum, calcite, dolomite, hematite, and amphibole. Freeze-dried samples were re-suspended onto the Teflon® filters for elemental analysis by X-ray fluorescence (XRF), while splits from each sample were analyzed for water-soluble cations and anions by ion chromatography. The dust deposits along the Red Sea coast are considered to be a mixture of dust emissions from local soils and soils imported from distal dust sources. Airborne mineral concentrations are greatest at or close to dust sources, compared to those through medium- and long-range transport. It is not possible to identify the exact origin of deposition samples from the mineralogical and chemical results alone. These aerosol data are the first of their kind from the Red Sea region. They will help assess their potential nutrient input into the Red Sea, as well the impact on human health, industry, and solar panel efficiency. These data will also support dust modeling in this important dust belt source area by better quantifying dust mass balance and optical properties of airborne dust particles.


Citation: Engelbrecht, J. P., Stenchikov, G., Prakash, P. J., Lersch, T., Anisimov, A., and Shevchenko, I.: Physical and chemical properties of deposited airborne particulates over the Arabian Red Sea coastal plain, Atmos. Chem. Phys., 17, 11467-11490, https://doi.org/10.5194/acp-17-11467-2017, 2017.
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Short summary
Desert dust has a profound impact on peoples health, visibility, damage to equipment, and global climate. This research is on dust from the Arabian Peninsula and aims at collecting and analyzing mineralogical, physical, and chemical composition of dust deposits from the atmosphere at the KAUST campus along the Red Sea in Saudi Arabia. The results will be used to assess the input of nutrients to the Red Sea, and will support dust modeling in the Middle East.
Desert dust has a profound impact on peoples health, visibility, damage to equipment, and global...
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