Vision And Project Concept
The project concept is based on integrating "bottom-up" approaches (emissions inventory driven regional climate modelling), with "top-down" constraints (source apportionment through multivariate modelling using in-situ measurements) to reduce uncertainties in understanding regional climate change impacts of carbonaceous aerosol (see Figure).
"Bottom-up" approaches use the development and deployment of an emissions inventory in atmospheric model simulations, which accounts for atmospheric transport, sinks and chemical conversion on regional scales. The outcome is an estimate of aerosol influence on climate variables like the radiation balance, temperature, and rainfall, which can be estimated by source type. Uncertainties in the magnitude and spatial distribution of emissions and in differences among models, contribute to uncertainties in the predicted effects.
"Top-down" approaches use in-situ measurements and receptor modelling, which exploits measurements of detailed chemical composition (mass, elements, ions, and organic and elemental carbon), sometimes in combination with emission composition, specific markers, satellite data, and trajectory ensembles. The outcome is the identification of the emission source types and their quantitative influence on carbonaceous aerosol concentrations.
In this project, a harmonization between these two approaches will be made to develop an emission inventory of carbonaceous aerosols for India, with bounded uncertainties. Information from both methods will be used to arrive at a rational understanding of sources which influence regional carbonaceous aerosol abundance over India. A suite of regional climate models, and some general circulation models will deploy the emission inventory to estimate carbonaceous aerosol effects on radiation, cloud properties, temperature, and rainfall over India.