Modeling Aerosols and Clouds with the Global Environmental Multiscale Air Quality (GEM-AQ) Model

Iziomon, M.G. and Lohmann, U., Department of Physics and Atmospheric Science, Dalhousie University
Fourteenth Atmospheric Radiation Measurement (ARM) Science Team Meeting

The Global Environmental Multiscale (GEM) model is an integrated forecasting and data assimilation system developed by the Meteorological Service of Canada and adapted for air quality (AQ) studies within the framework of the Multiscale Air Quality Network (MAQNET). The model has a variable resolution capability and a semi-implicit semi-Lagrangian time discretization scheme. It has a hydrostatic-pressure-type hybrid vertical coordinate with 28 levels and model top at 10 mb. The physics package in the model includes turbulent vertical diffusion, deep convection and condensation processes, while the aerosol representation is based on the Canadian aerosol module (Gong et al., 2003). At present, the model has 37 advected gas phase species as well as 12 size bins sea salt and sulfate aerosols, with an ongoing effort to include carbonaceous aerosols. Here, we present and substantiate preliminary global uniform (4X4) model results for aerosols and clouds, with a particular reference to aerosol photochemistry, aerosol size and spatial distribution, as well as continental and maritime cloud properties. We discuss the implications of these results for the different ARM sites. Reference: Gong, S. L., L.A. Barrie, J.-P. Blanchet, K. von Salzen, U. Lohmann, G. Lesins, L. Spacek, L.M. Zhang, E. Girard, H. Lin, R. Leaitch, H. Leighton, P. Chlek and P. Huang, Canadian Aerosol Module: A Size Segregated Simulation of Atmospheric Aerosol Processes for Climate and Air Quality Models: 1. Module Development, J. Geophys. Res., 108, doi: 10.1029/2001JD002002, 2003.

Note: This is the poster abstract presented at the meeting; an extended version was not provided by the author(s).