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Mikhail Ovtchinnikov Pacific Northwest National Laboratory P.O. Box 999/K9-24 Richland, WA 99352 email: Mikhail.Ovtchinnikov@pnl.gov The effect of clouds on aerosol distribution is important but quantitatively poorly understood and crudely represented in regional and global models. Our objectives are to improve understanding of aerosol processing by clouds and to transfer this knowledge into parameterizations suitable for large-scale models. Aerosol transformations will be studied using the Cloud and Aerosol Interactive Model (CLAIM), which combines a three-dimensional large eddy simulation framework with a new comprehensive representation of aerosol and cloud processes based on a two-dimensional (dry and total volumes) particle size distribution function. This approach, while computationally intensive, provides a benchmark that consistently tracks evolution of aerosol subjected to micro and macrophysical processes including particle transport, sedimentation, activation/resuspension, condensation/evaporation, collision/coalescence, aqueous chemistry, and in- and below-cloud scavenging. The dependency of cloud processing on aerosol composition will be further studied in a Lagrangian parcel model, where multiple distributions of inorganic and organic aerosols will be simulated along the trajectories generated by the CLAIM. Both models will be thoroughly evaluated in case studies based on Atmospheric Science Program field campaigns. In addition to testing the fidelity of the model predictions, our simulations will contribute to designing sampling strategies and improving. [back to ASP ST Membership] |