Direct Aerosol Radiative Forcing Over Three Different Environments

Abstract

In the present report, we have utilised the inversion products of AERONET to study the aerosol optical properties and to estimate their direct adiative forcings over three different environments (Re Union, Nainital and Pune). Derived aerosol optical properties over all stations showed significant temporal (seasonal) and spatial variation. These properties have been used in SBDART model for the assesment of direct aerosol radiative forcing. The estimated averaged radiative forcings at top of the atmosphere are-2 ± 1,-7 ± 4 and-8 ± 2 Wm-2 , and the surface aerosol radiative forcings are-6 ± 3,-18 ±14 and-36 ± 8 Wm-2 over Re Union, Nainital and Pune respectively. Subsequntly the atmospheric forcings are 3 ± 2, 11 ± 11 and 28 ± 7 Wm-2 over Re Union, Nainital and Pune respectively. Moreover, we found that higher the aerosol loading or aerosol optical depth the more aerosol radiative forcing. The estimated atmospheric aerosol radiative forcing will heats the lower atmosphere and leads modification of the thermal structure of the atmosphere. Hence, our study emphasized the importance of optical properties of aerosols in the estimation of direct aerosol radiative forcing.