Applications of Models-3 in Coastal Areas of Canada M. Lepage, J.W. Boulton, X. Qiu and M. Gauthier RWDI AIR Inc. C. di Cenzo Environment Canada, P&YR 3rd Annual CMAS Models-3 Workshop October 18-20, 2004 Chapel Hill, NC

Modelling Domains (4-km)

Factors to be considered: Meteorological fields (MM5, MC2…) Emission inventory and modeling CMAQ Chemical mechanism (SAPRC-99, CB-IV & RADM2…) Grid resolution and domains Monitoring data and evaluation methods

Western Canada: MC2, SMOKE, CMAQ Modeled events: Aug ’01, Dec ‘02 4 km grid in MC2 (from UBC) Emission Inventories: 2000 (GVRD), 1995 (BC), 1999 (US), BEIS3 12 km, 4 km grids in CMAQ RADM2, SAPRC99

CMAQ Model Results

Pitt Meadows Modelled & Observed Time Histories Ozone, Aug. 9 – 20, 2001 ppb Day Better nighttime ozone ppb Day Nighttime ozone sensitive to grid resolution… Day ppb

Pitt Meadows NO 2 Day Under-prediction Ozone Good NO 2 Predictions Recent tests suggest better results with SAPRC99… ppb NO 2 Modelled & Observed Time Histories Ozone, Aug. 9 – 20, 2001 (cont’d)

CMAQ Model Results

Modeled & Observed Time Histories: PM2.5, Aug. 9 – 20, 2001 PM 2.5 (µg/m 3 ) No 2 (ppb) Precursor diurnal Pattern propagated to secondary PM p-nitrate (ug/m 3 ) Too strong diurnal circle

Eastern Canada: MM5, SMOKE, CMAQ Modeled events: Jul ’99, Aug ‘01 Emission Inventories: 1995 (EC), 1999 (US), BEIS3 36 km, 12 km, 4 km grids in CMAQ CB4, SAPRC99

Model Performance: Ozone Time Histories for Nearby, 4-km Resolution Urban (red) and Suburban (green) Monitoring Sites, Hamilton, Ontario Ozone Predicted (blue) nighttime ozone aligns better with the suburban monitoring site Daytime obs ozone the same at both sites

PM2.5 Sulfate dominated aerosol: precursor diurnal cycles not propagated. Model Performance: PM 2.5 Time Histories for Nearby, 4-km Resolution Urban (red) and Suburban (green) Monitoring Sites, Hamilton, Ontario

CMAQ Performance Hourly and daily Ozone predictions are overall reasonably good in western and eastern Canada, (sometimes poor at night) Kz(min) could be a contributing factor? Grid resolution is important for ozone predictions, especially at nighttime (NOx): higher resolution is better Meteorological inputs can be a major factor Chemical mechanism also plays a role

CMAQ Performance (cont’d) Daily mean PM predictions are reasonably good in western and eastern Canada Hourly values are generally poor, but somewhat better for Eastern Canada SOA module could be a contributing factor? Better biogenic emissions and temporal factors are needed, especially in western Canada due to biogenic SOA. Meteorological inputs can be a major factor Chemical mechanism also plays a role

MM5 or MC2 can produce the necessary meteorological inputs. However, there is uncertainty in PBL predictions relating to : Model grid resolution Geophysical fields Initial and boundary conditions Microphysics and convective parameterization schemes PBL and surface schemes ???

MC2 Sensitivity Study Sensitivity tests on 4 km and 2 km grid resolutions (13 runs) combining: 24km GEM output as initial fields ISBA surface scheme Kain-Fristch deep convective scheme Kong-Yau microphysics scheme Improved geophysics resolution Increased vertical grid resolution

MC2 Sensitivity Study: Preliminary Results

CONCLUSIONS Reasonably good performance for 1-hr and 24-hr ozone and 24-hour PM2.5 Better ozone diurnal pattern on 4 km grid than on 12 km grid Working on improvements to meteorological fields Problems with PM and SOA chemistry – now working with SAPRC99