Abstract The existence of elevated aerosol layer is common over India during monsoon season. Though its sources are well explained through long-range transport, its formation and maintenance is not explained to date. The formation and maintenances of an elevated aerosol layer, starting from ∼2 km and extending up to ∼5.5 km noticed is explained using two nearby lidars located in peninsular India. Existence of a cleaner environment with low aerosol loading below 2 km is attributed to the wet scavenging and existence of no strong local source. The low level jet (LLJ) from Arabian Sea persisting between 2 and 3 km is the main mechanism suggesting strong role of dynamics in the formation of these elevated layers. Persistent strong shears existing between LLJ and tropical easterly jet during this season restrict the up-liftment of aerosols to the higher altitudes. Observed features are explained in the light of dynamics, meteorology and long-range transport.

中文翻译：

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动力学对印度东南半岛季风季节气溶胶层形成和维持的作用

摘要 季风季节，印度普遍存在气溶胶层升高。虽然它的来源可以通过远程传输得到很好的解释，但迄今为止还没有解释它的形成和维护。使用位于印度半岛附近的两个激光雷达解释了升高的气溶胶层的形成和维持，从约 2 公里开始并延伸到约 5.5 公里。低于 2 公里的低气溶胶负载的清洁环境的存在归因于湿清除和不存在强的局部源。来自阿拉伯海的低空急流 (LLJ) 持续 2 至 3 公里是主要机制，表明动力学在这些高架层的形成中起着重要作用。本季低空急流与热带东风急流之间存在的持续强切变限制了气溶胶向更高海拔的抬升。观察到的特征根据动力学、气象学和远程传输进行解释。