Laser radar monitoring of tropospheric aerosols

Abstract

A bistatic laser radar (using a continuous wave argon ion laser) installed at the Indian Institute of Tropical Meteorology (IITM), Pune, for remote sounding of atmospheric aerosol characteristics has been briefly described. The day-to-day and height-time variations in the vertical distribution of aerosol number density (up to 3680 m AGL) have been studied by operating the radar on 6 clear days during nighttime in the month of April 1987. The results of study indicted the formation and redistribution of aerosol layer structure in the lower altitudes (up to 1800 m). Also, conspicuous differences in the height distribution of aerosol number density were notices between the post-sunset and pre-sunrise periods. The observed features have been explained on the basis of aerosol transport and diffusion processes occurring in the nocturnal urban atmosphere