Extended Abstract (108K)J5.9
MM5 cloud prediction and its impact on CMAQ modeling in Southern Ontario
Xin Qiu, Rowan Williams Davies & Irwin Inc., Guelph, ON, Canada; and M. Lepage
A regional air quality modeling study was done for a typical summer smog episode that occurred in Northeast of United States and Southern Ontario in July 13-17, 1999. The MM5/SMOKE/CMAQ modeling system was used for this study. Sensitivity tests indicated that the MM5 cloud prediction can significantly impact the photochemical processes, therefore affecting the ground ozone and fine particulate matter levels significantly. The photolysis rates in CMAQ require cloud correction factors through MCIP which is tightly linked to the MM5 cloud prediction . However, appropriate cloud predictions in MM5 rely on the selection of a cumulus parameterization and microphysics condensation scheme that correspond to the MM5 model resolutions, the weather conditions being modeled and the other correlated physics options.
Joint Session 5, Atmospheric Chemistry (Joint with the Fourth Symp. Urban Environment, 12th Joint Conf. on the Applications of Air Pollution Meteorology with A&WMA, and 25th Conf. Agricultural & Forest Meterology; Cosponsored by the AMS STAC Committee on Atmospheric Chemistry)
Thursday, 23 May 2002, 1:30 PM-4:59 PM
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