Northwest Columbia Plateau PM10 Project Objectives 3 and 4: Characterization of Ambient PM10 Title: Measurement and Modeling of PM10 from Windblown Dust

of Research Findings In 2005, our efforts transitioned from work on the original CP3 windblown dust modeling system toward a new state-of-the-art system based upon the combination of the AIRPACT-3 automated air quality modeling system with the WEPS erosion modeling system. We also brought to a close, field work at the intensive windblown dust field site, and we continued to have a very active role related to PM2.5 issues associated with agricultural field burning. Results from an extensive set of revised modeling runs using the CALGRID/EMIT CP3 modeling system were published in the Journal of Geophysical Research in December, 2004, and this marked the conclusion of use of this system. During 2005, we began work on the implementation of the USDA Wind Erosion Prediction System (WEPS) model as part of our automated AIRPACT-3 regional air quality modeling system. AIRPACT-3 employs the MM5 numerical weather model with the EPA Community Multi-scale Air Quality (CMAQ) model to simulate detailed gas and particulate phase pollutant behavior for the Pacific Northwest ( http://www.airpact-3.wsu.edu/). Our goal is to employ WEPS to treat soil and land cover processes along with management practices to provide PM10 dust emissions for the AIRPACT-3 system. This combination will provide a basis for simulation of selected historical events, analysis of new management practices, and incorporation of dust as part of the forecast component of AIRPACT-3. In 2005, we developed a simple demonstration of windblown dust in AIRPACT-3 and we began to compile the appropriate land cover and soil data bases for incorporation of WEPS into AIRPACT-3. The ClearSky agricultural smoke forecast system was operated during the 2005 summer and fall burn season in eastern Washington, northern Idaho, and the Clearwater region of central Idaho. The system was evaluated for the 2004 burn season and results shows that the model was extremely sensitive to uncertainties in the modeled wind fields. Field measurements were conducted to obtain estimates of plume rise from agricultural field burns and also to obtain additional PM2.5 emissions information. Work was also begun on the development of an ensemble smoke dispersion forecast system where 17 different meteorological forecasts were used to drive the smoke dispersion model.