This study investigates the spatiotemporal distribution of the major aerosol species (sulfate, organic matter, black carbon, dust, and sea salt) and their contributions to the total aerosol optical depth (AOD) over Egypt from 2010 to 2019 by using the Copernicus Atmosphere Monitoring Service (CAMS) reanalysis data. Dust was the major aerosol species, with an average contribution of 48% to the total AOD. The highest concentrations of dust were found in spring because of the significant impact of the Khamsin wind in carrying sand aerosols from deserts. The dispersion of dust aerosols is greatly influenced by topography. While lowlands, such as the Qattara Depression, accumulate sand aerosols from the surroundings, the mountainous highlands disrupt horizontal diffusion. El-Farafra and Siwa Oasis, which are close to the Qattara depression, had significant dust contributions to the total AOD. Because the Nile Delta, Suez Canal, and Nile River regions are densely populated and industrialized, organic matter and sulfate showed considerable contributions of 24% and 23%, respectively, to the total AOD. The highest concentrations of organic matter and sulfate were found in summer because of the high temperatures that accelerate photochemical reactions. While fossil fuels and biomass burning increase carbon emissions in cities such as Cairo and Tanta, shipping in the Suez Canal and natural gas flares in the eastern Mediterranean increase sulfate aerosols in cities such as Port Said, Suez, and Arish. Black carbon and sea salt were the minor aerosol species, with average contributions of 3% and 2%, respectively, to the total AOD.

中文翻译：

---

基于 10 年 CAMS 再分析数据的埃及主要气溶胶种类特征

本研究利用哥白尼大气监测，调查了 2010 年至 2019 年埃及主要气溶胶种类（硫酸盐、有机物、黑碳、灰尘和海盐）的时空分布及其对总气溶胶光学深度（AOD）的贡献服务 (CAMS) 再分析数据。粉尘是主要的气溶胶种类，平均占 AOD 总量的 48%。由于康辛风携带沙漠沙气溶胶的显着影响，春季灰尘浓度最高。粉尘气溶胶的扩散受地形影响很大。虽然卡塔拉洼地等低地积聚了周围的沙气溶胶，但山区高地却扰乱了水平扩散。靠近 Qattara 洼地的 El-Farafra 和 Siwa Oasis 对 AOD 总量有显着的尘埃贡献。由于尼罗河三角洲、苏伊士运河和尼罗河地区人口密集且工业化程度高，有机质和硫酸盐对总AOD的贡献率相当大，分别为24%和23%。由于高温加速了光化学反应，有机物和硫酸盐的浓度在夏季最高。虽然化石燃料和生物质燃烧增加了开罗和坦塔等城市的碳排放，但苏伊士运河的航运和地中海东部的天然气火炬增加了塞得港、苏伊士和阿里什等城市的硫酸盐气溶胶。黑碳和海盐是次要气溶胶种类，对 AOD 总量的平均贡献分别为 3% 和 2%。