Bridging the last few kilometers: Accounting for Subgrid mixing and spatial gradients in global aerosol models
DESCRIPTION: Global models are beginning to include processes that depend on detailed aerosol properties to better represent direct and indirect climate forcing. New aerosol representations include aerosol number, surface area, composition, and mixing state. However, since these properties are not given for emissions, the aerosol fields are not initialized correctly, nor is near-source evolution represented properly. Changes in aerosol properties occur over distances that are small compared to a global model grid box.
OUTCOMES: The goal of the project “Bridging the Last Few Kilometers” is representing critical, climate-relevant microphysical properties of aerosols for appropriate use in global models. The two partners in the project are the University of Illinois, working on modeling of aerosol evolution immediately after emission, and NASA-Goddard Institute for Space Studies, implementing aerosol microphysics in a global model and testing global sensitivities.