Latitudinal distribution of aerosol black carbon and its mass fraction to composite aerosols over peninsular India during winter season

Abstract

During a land campaign to characterise the spatial distribution of aerosols over peninsular India during the winter season, extensive, collocated, and spatially resolved measurements of mass concentration of the composite aerosols (M T ) as well as that (M B ) of aerosol Black Carbon (BC) were made over different environments (coastal, industrial, urban, village, remote, semiarid) of the western peninsular India. High concentrations of BC, >2.5 μ g m −3 , were observed along the west coast, from ∼8°N up to 14.5°N, and moderate values (1.0 to 2.5 μ g m −3 ) over inland regions from 15 to 18°N. Latitudinally, BC concentration decreased from south to north, @∼160 ng m −3 for every degree increase in latitude. The spatial pattern of BC mass fraction differed from that of M B, with regions of high (8 to 16%) ratios spreading more interior, implying higher fractional load of BC at locations where the BC concentrations remain lower.