AIRPACT-3: air quality forecasting for the Pacific and Inland Northwest U.S. and nearby British Columbia

Since 2001, AIRPACT has provided daily forecasts of photochemical pollutants for the Pacific Northwest. The initial AIRPACT domain covered only the Puget Sound area; AIRPACT-2 expanded northward into Canada and southward into Oregon; AIRPACT-3 expands the domain further to cover Idaho, Oregon and Washington. AIRPACT began with use of the CALGRID photochemical model; AIRPACT-3 substitutes the CMAQ-CCTM photochemical and aerosol model.

In AIRPACT-3, 12-km MM5 forecast meteorology (from the UW mesoscale forecasting group) flows through the MCIP meteorological processor to a SMOKE-based emissions subsystem and to the CMAQ model. CMAQ-CCTM is run in parallel on multiple processors in a Linux system, with results being visualized using the PAVE tool for display on the project web site. Verification of model results is addressed through post-forecast processing of networked observations, for both air-quality and meteorological measures, for statistical analysis, and display of both statistical and graphical verification products via the project web site.

The AIRPACT-3 system design will be presented, with emphasis on the post-processing and verification system, and illustrated through presentation of aerosol results for Fall 2005.