Impact of Asian Dust Storms on Downwind Regions as Simulated by the CAM/CARMA Dust Model

We developed a three-dimensional coupled microphysical/climate model based on the NCAR Community Atmospheres Model and the University of Colorado/NASA Community Aerosol and Radiation Model for Atmospheres. The model is used to investigate the sources, removal processes, transport and optical properties of Asian dust storms and their impact on downwind regions. The model simulations are conducted during the period of the ACE-Asia field experiment since considerable in situ data are available at that time. Our dust source function follows Ginoux et al. [2001]. We modified the source function by using the friction velocity instead of the 10-meter wind based on the wind erosion theory. Generally, we reproduce the particle size distributions retrieved by AERONET Sun photometers. The temporal and spatial patterns of aerosol optical depths agree well with the ground-based AERONET data and MODIS, TOMS AI satellite observations. We also find the Angstrom exponent and the single scattering albedo compare well to AERONET observations. The vertical profiles of dust are comparable to the ACE-Asia 2001 NIES-lidar observations in Beijing area.