Abstract |
The dry deposition module of the Regional Acid Deposition Model (RADM) is used to compute the dry deposition velocities (downward flux divided by concentration at a specified height) for SO2, SO4(2-), O3, and HNO3, among others. With its computerized landuse map, the module can provide estimates of the deposition velocities for a given set of meteorological and surface conditions that are representative of an area located anywhere in the contiguous United States and nearby locations. As part of the project, the module has been modified to accept data on meteorological and surface conditions observed at measurement stations rather than use inputs computed with RADM. The purpose of these modifications was to make site-specific estimates of dry deposition velocities, and compare these with results from the site-specific inferential technique that has been developed at the Atmospheric Turbulence and Diffusion Division of NOAA's Air Resources Laboratory. Goals of the comparisons include estimating the relative uncertainties of the two techniques, suggesting improvements, and examining the ability of the modified module to provide estimates of dry deposition for expanded areas around the measurement sites. |