| Two dry deposition schemes i.e., RADM and M3DRY in the MCIPv2.3 of the Models-3/CMAQ framework are analyzed to investigate the impact of dry deposition velocities on gaseous pollutant concentrations in Southeast Texas. The Southeast Texas areas of Houston-Galveston (HGA) and Beaumont-Port Arthur (BPA) have been designated as severe and moderate ozone non-attainment areas respectively. The dry deposition of O3 is controlled by the canopy resistance during the day-time hours in the urban and rural areas. During night-times, the dry deposition of O3 in urban regions is controlled by aerodynamic, as well as canopy resistance. Dry deposition velocities estimated by RADM do not exhibit strong diurnal variations and have similar magnitudes in both the urban and rural areas of the studied domain; predominantly due to the high stomatal resistance values in RADM. Daily average flux computed for O 3 by M3DRY is 1.5 times that computed by RADM for HGA and rural regions, and 1.8 times for BPA. (Abstract shortened by UMI.)... |
