Sources and optical properties of Black Carbon (BC) aerosols from India and China: Constraints by field observations

Project leader


Funding source

Formas - The Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning

Project Details

Start date: 01/01/2016
End date: 31/12/2019
Funding: 3000000 SEK


Black carbon (BC) containing aerosols filling the atmosphere of S and E Asia cause severe effects on both climate and the quality of the air people breathe, yet scientific uncertainties abound for BC including a factor of two lower estimate of BC climate forcing by models compared to field observations. We hypothesize that this serious offset stems from large uncertainties in BC emission inventories and possibly in current parameterization of the optical properties of aged BC aerosols. We propose to capitalize on unique access to a network of sites both in Indian and Chinese megacities and in downwind ocean island receptor observatories to provide observation-based constraints on emission sources and optical properties of the BC in the actual atmosphere. Combined microscale-14C, 13C and molecular markers will provide quantitative apportionment between different fossil and biomass combustion sources. Inverse estimates of BC emission fluxes (Gt/yr) for India and China will be constrained by coupling receptor time series BC/CO with a dispersion model and better constrained EI for CO. The refractive light absorption enhancement by coatings of ambient BC will be explored by a decoating procedure. Observationally-constrained BC sources, emissions and optical properties will aid both air quality and climate models. The source apportionment of BC from India and China will be communicated to stakeholders in Sweden and in Asia to support effective mitigation policies.

Last updated on 2017-07-08 at 11:13