Micro pulse lidar observations of mineral dust layer in the lower troposphere over the southwest coast of Peninsular India during the Asian summer monsoon season

作者：Mishra Manoj Kumar; Rajeev K^*; Thampi Bijoy V; Parameswaran K; Nair Anish Kumar M

来源：Journal of Atmospheric and Solar-Terrestrial Physics, 2010, 72(17): 1251-1259.

DOI：10.1016/j.jastp.2010.08.012

• Aerosol transport
• Mineral dust
• Lidar
• Asian summer monsoon
• Indian region

A large aerosol plume with optical depth exceeding 0.7 engulfs most parts of the Arabian Sea during the Asian summer monsoon season. Based on Micro Pulse Lidar observations during the June-September period of 2008 and 2009, the present study depicts, for the first time, the existence of an elevated dust layer occurring very frequently in the altitude band of 1-3.5 km over the west coast of peninsular India with relatively large values of linear depolarization ratio (delta(L)). Large values of delta(L) indicate the dominance of significantly non-spherical aerosols. The aerosol optical depth of this layer (0.2) is comparable to that of the entire atmospheric column during dust-free days. Back-trajectory analysis clearly shows the advection of airmass from the arid regions of Arabia and the west Arabian Sea, through the altitude region centered around 3 km. This is in contrast to the airmass below 1 km originating from the pristine Indian Ocean region which contains relatively spherical aerosols of marine origin with delta(L) generally <0.05.

• 出版日期2010-11