Delhi National Capital Region (NCR) of India is one of the most polluted regions in the world, yet only two ground-based monitoring sites under the AEROsol RObotic NETwork (AERONET) measuring Aerosol Optical Depth (AOD) are operational in this region. Here, we assessed the performance of Terra and Aqua MODIS collection 6.1 AOD product to understand their applicability for studying seasonal and spatial variations of AOD over Delhi-NCR. We compared Deep Blue AOD at 550 nm retrieved at 10 km resolution (DB_10K), and Dark Target AOD retrieved at 3 km (DT_3K) and 10 km (DT_10K) resolutions against AOD from these two AERONET sites (Gual Pahari and Amity University) during 2010–2019 keeping in mind the uncertainty range represented as expected error (EE) envelope [EE = ± (0.03 + 20% AOD_AERONET) for DB_10K, EE = ± (0.05 + 20% AOD_AERONET) and EE = ± (0.05 + 15% AOD_AERONET) for DT_3K and DT_10K respectively]. Our evaluation reveals the following statistics: correlation coefficients (R) of 0.44, 0.74, and 0.77 for DB_10K, DT_3K, and DT_10K AODs from TERRA and 0.7, 0.79, and 0.72 from AQUA, respectively and root mean square errors of 0.26, 0.01, and 0.17 for AODs from TERRA and 0.24, 0.20, and 0.24 for AODs from AQUA, respectively. Our results demonstrate better reliability of the DT AOD products relative to DB over urbanized areas in North India. Emission from industries, power plants, brick kilns, enhances aerosol loading after a light precipitation event.

印度的德里国家首都辖区（NCR）是世界上污染最严重的地区之一，但该地区仅在测量气溶胶光学深度（AOD）的气溶胶机器人网络（AERONET）下有两个地面监测站点。在这里，我们评估了Terra和Aqua MODIS collection 6.1 AOD产品的性能，以了解它们在研究德里NCR上AOD的季节性和空间变化方面的适用性。我们比较了以10 km分辨率（DB _10K）获得的550 nm深蓝色AOD和以3 km（DT _3K）和10 km（DT _10K）获得的Dark Target AOD）在2010-2019年期间针对这两个AERONET站点（瓜拉帕哈里大学和Amity大学）针对AOD的解决方案，同时请记住，对于DB _10K，不确定性范围表示为预期误差（EE）包络[EE =±（0.03 + 20％AOD _AERONET）DT _3K和DT _10K的EE =±（0.05 + 20％AOD_航空网）和EE =±（0.05 + 15％AOD_航空网）。我们的评估揭示了以下统计数据：DB _10K，DT _3K和DT _10K的相关系数（R）分别为0.44、0.74和0.77TERRA的AOD和AQUA的AOD分别为0.7、0.79和0.72，TERRA的AOD的均方根误差为0.26、0.01和0.17，AQUA的AOD的均方根误差分别为0.24、0.20和0.24。我们的结果表明，在印度北部城市地区，DT AOD产品相对于DB的可靠性更高。工业，发电厂，砖窑的排放增加了轻度降水事件后的气溶胶负荷。