The study aimed at using Moderate Resolution Imaging Spectroradiometer (MODIS-Terra) to investigate long-term spatial and temporal aerosol variations over Zambia during 2000–2020. Based on data availability, ground truthing for MODIS-Terra was done over Mongu in western Zambia using Aerosol Robotic Network (AERONET) data for 2001–2009. The correlation coefficient between MODIS-Terra and AERONET is 0.42 and statistically significant at 95% confidence level. The aerosol optical depth at 550nm (AOD₅₅₀) and Angstrom exponent (AE_470-870) annual mean spatial distribution indicates high and moderate to low patterns explaining distinct features of aerosol loadings from different areas over Zambia. Generally, the AOD₅₅₀ and AE_470-870 spatial gradient values increase from southern to northern Zambia explaining fine mode particles mainly produced by local intensive anthropogenic and urban/small and large-scale industrial emission activities in the cities. Seasonal climatology reveals that highest AOD₅₅₀ is observed during SON, followed by JJA, DJF, with the lowest recorded during MAM. It is also observed from AE_470-870 that fine particles are prominent during JJA and SON. The insignificant decreasing (increasing) trend of AOD₅₅₀ is revealed over Mwinilunga, Misamfu, Mfuwe, Choma, and Kabwe (Mongu). Further results showed that fire hotspot density intensifies over central parts of Africa, including Zambia from June to November. Moreover, the 5-day air mass back trajectory analysis suggests that aerosol sources over Zambia are associated with short- and long-distance ranges from East Africa, Congo Basin, Madagascar, and Atlantic and Indian oceans with diverse transport pathways in different seasons. These findings may help enhance a better understanding of climatic effects and atmospheric aerosol sources in Zambia.

该研究旨在使用中分辨率成像光谱仪 (MODIS-Terra) 调查 2000-2020 年期间赞比亚上空的长期时空气溶胶变化。根据数据可用性，使用气溶胶机器人网络 (AERONET) 2001-2009 年的数据在赞比亚西部的蒙古完成了 MODIS-Terra 的地面实况。MODIS-Terra 和 AERONET 之间的相关系数为 0.42，在 95% 的置信水平下具有统计显着性。550 nm 处的气溶胶光学深度 (AOD ₅₅₀ ) 和埃指数 (AE _470-870 ) 年平均空间分布表明高、中到低模式，解释了来自赞比亚不同地区的气溶胶负载的不同特征。一般来说，AOD ₅₅₀和 AE _470-870空间梯度值从赞比亚南部到北部增加，解释了主要由当地密集的人为和城市/小型和大型工业排放活动产生的细模式粒子。季节性气候学显示，在 SON 期间观察到的AOD 最高₅₅₀，其次是 JJA、DJF，在 MAM 期间记录到的最低。从 AE _470-870还观察到细颗粒在 JJA 和 SON 期间很突出。AOD ₅₅₀下降（上升）趋势不明显在 Mwinilunga、Misamfu、Mfuwe、Choma 和 Kabwe（蒙古）上被揭示。进一步的结果表明，从 6 月到 11 月，包括赞比亚在内的非洲中部地区的火灾热点密度加剧。此外，为期5天的气团反向轨迹分析表明，赞比亚上空的气溶胶源与东非、刚果盆地、马达加斯加以及大西洋和印度洋的短距离和长距离范围有关，不同季节具有不同的运输途径。这些发现可能有助于更好地了解赞比亚的气候影响和大气气溶胶来源。