Abstract Since the past two decades, high aerosol loading is being observed over the Indian mainland. It becomes necessary to continuously monitor and understand the distribution of aerosol loading over the Indian landmass, as it might have serious health and climatic implications. Whereas there have been extensive studies reporting seasonal distribution and trends of columnar aerosol amounts over the Indian region using data from ground based as well as space borne measurements, in-depth studies on the aerosol vertical profile distribution and in particular, seasonal trends are still lacking. This paper demonstrates the seasonal variability of aerosol vertical structure over the Indian mainland using decadal daily datasets (2009–2018) from CALIOP Lidar (onboard NASA-CNES's CALIPSO satellite) augmented by the variability in columnar AOD from MODIS (onboard NASA's AQUA and TERRA platforms). The changing aerosol amounts in both vertical and total column levels have also been presented. Over Indian landmass, we could find statistically significant increasing trends in aerosol extinction within lower altitude levels during all the seasons. The trends in the vertical distribution of aerosols are also compared with respect to trends in AOD derived from MODIS (Aqua/Terra). Additionally, we have also examined the seasonal variability and trends of aerosol extinction over five selected cities (based on pollution and population levels) of the country.

中文翻译：

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印度大陆气溶胶垂直分布的星载观测（2009-2018）

摘要 自过去二十年以来，在印度大陆上一直观察到高气溶胶载荷。有必要持续监测和了解印度陆地上气溶胶载荷的分布，因为它可能对健康和气候产生严重影响。虽然已经使用来自地面和空间测量的数据报告了印度地区柱状气溶胶量的季节性分布和趋势，但对气溶胶垂直剖面分布的深入研究，特别是季节性趋势仍然缺乏. 本文使用 CALIOP 激光雷达（NASA-CNES 机载）的十年日数据集（2009-2018）展示了印度大陆气溶胶垂直结构的季节性变化。s CALIPSO 卫星）通过来自 MODIS（在 NASA 的 AQUA 和 TERRA 平台上）的柱状 AOD 的可变性增强。还介绍了垂直和总柱水平中气溶胶量的变化。在印度陆地上，我们可以发现所有季节在较低海拔水平内气溶胶灭绝的统计显着增加趋势。气溶胶垂直分布的趋势也与源自 MODIS (Aqua/Terra) 的 AOD 趋势进行了比较。此外，我们还研究了该国五个选定城市（基于污染和人口水平）的季节性变化和气溶胶灭绝趋势。我们可以发现，在所有季节，在较低海拔高度范围内，气溶胶消光率都有统计学上显着的增加趋势。气溶胶垂直分布的趋势也与源自 MODIS (Aqua/Terra) 的 AOD 趋势进行了比较。此外，我们还研究了该国五个选定城市（基于污染和人口水平）的季节性变化和气溶胶灭绝趋势。我们可以发现，在所有季节，在较低海拔高度范围内，气溶胶消光率都有统计学上显着的增加趋势。气溶胶垂直分布的趋势也与源自 MODIS (Aqua/Terra) 的 AOD 趋势进行了比较。此外，我们还研究了该国五个选定城市（基于污染和人口水平）的季节性变化和气溶胶灭绝趋势。