Characterizing and quantifying the effect of aerosol optical depth over North Indian plain during harvesting season

Abstract

This paper analyses the dynamics of AOD over north-western part of northern Indian plain during the harvesting season its effect on surface reaching solar radiation from 2001 to 2009 using MODIS level 2 atmospheric data set.The analysis carried out for post monsoon season during rice harvesting period and is based on 8 days composite AOD, Ozone, Water vapour, and surface pressure data.Spatial variability of AOD has been shown in 0.47 μm and 0.66 μm in order to grasp the idea of relative difference in occurrence of fine and coarse mode aerosol.Analysis of the particles under SEM-EDX collected through air sampling in the agricultural field in Punjab and Haryana during rice harvesting season shows released particles from the residue burning have 72% of O, 8% of C, 7% of Si, 2% Al, and 7% F in significant amount and barely less that equal to 1% of other elements such as Na, K, Ba, Mg, Fe, Ca, Ti, Zn, P, and Cl.NOAA-HYSPLIT back trajectory analysis shows these emitted smoke and aerosol plumes which transport a long distance through active wind system affect insolation amount at the surface.AOD levels between 2003 and 2007 were moderate to high in the western part of North Indian plain, with an average of 0.8-1.8 at 0.47 μm and 0.6-1.4 at 0.66 μm.Radiative forcing in this region during the study period vary pronouncedly amounting to -20 Wm-2 to 11Wm-2.