Measurement report: quantifying source contribution of fossil fuels and biomass-burning black carbon aerosol in the southeastern margin of the Tibetan Plateau

Abstract. Anthropogenic emissions of black carbon (BC) aerosol are transported from Southeast Asia to the southwestern Tibetan Plateau (TP) during pre-monsoon; however, quantities BC different anthropogenic sources and transport mechanisms still not well constrained because there have been no high-time-resolution source apportionments. Intensive measurements were taken in a channel for pollutants southeastern margin TP pre-monsoon investigate influences fossil fuels biomass burning on BC. A receptor model that coupled multi-wavelength absorption with species concentrations was used retrieve site-specific Ångström exponents (AAEs) mass cross sections (MACs) An “aethalometer model” those values showed had larger contribution than (BCbiomass=57 % versus BCfossil=43 %). The potential function indicated BCbiomass site northeastern India northern Burma. Weather Research Forecasting chemistry (WRF-Chem) 40 originated Asia, while high BCfossil southwest sampling site. radiative transfer average atmospheric direct effect (DRE) +4.6 ± 2.4 W m−2, +2.5 1.8 m−2 +2.1 0.9 BCfossil. DRE produced heating rates 0.07 0.05 0.06 0.02 K d−1, respectively. This study provides insights into over influence cross-border transportation biomass-burning pre-monsoon.