GEM-MACH Global The Canadian Global Air Quality Modeling/Forecasting System Dr. Sunling Gong Science and Technology Branch January 16-17, 2012
Page 2 – October 9, 2015 Outline Introduction to Canadian AQ forecasting system: GEM-MACH; System structure; Three major components; emissions, gases and aerosols; Summary of applications.
Page 3 – October 9, 2015 "Multiscale" Examples: Three GEM Grid Configurations global regional limited area
Page 4 – October 9, 2015 GEM-MACH - Structure SMOKE Regional Data Canada & US Gas Phase Chemistry CAM Canadian Aerosol Module ISORROPIA Equilibrium Scheme GEM Meteorology Transport Emission InterfaceChemistry Interface Global Emissions
Page 5 – October 9, 2015 Global Emissions
Page 6 – October 9, 2015 NA anthropogenic 42 km, hourly CAN wildfires 0.4 deg, hourly EU anthropogenic SA/EA anthropogenic 0.4 deg, hourly/monthly Implementation of Regional Gridded Emissions
Page 7 – October 9, 2015 GEM-MACH emission pre-processor Combination of: - global emission inventories from EDGAR/MOZART (“background”) - continental/regional emissions from different sources (“AQ study domains”) - Current global emission maps: - biomass burning, industrial, biogenic [EDGAR] (1) - fossil fuel [Cooke, 1999] (2) - biomass burning [Liousse, 1996] (2) Current regional emission maps: - Canadian wildfires (1)+(2) - boreal and temperate vegetation fires (1)+(2) - Canada and United States [AURAMS] (1)+(2) - Asian anthropogenic, biomass burning [ACE-Asia & INTEX B] (1)+(2) (1) Gases, SO4, NO3; (2) BC, OC
Page 8 – October 9, 2015 North American Emissions AREA (gridded emissions) Inventories - CAN US MEX 1999 Area emissions files contains - on road (cars, trucks, motorcycles,...) - off road (boat, train, construction vehicles, aircraft...) - other types (agriculture, industries,...) Major points sources (none gridded emissions) - more than major points sources - stack height > 30 m for Canada - stack height > 35 m for US
Page 9 – October 9, 2015 INTEX-B Area - Asia
Page 10 – October 9, 2015 Global BC/OM emissions Boreal and temperate wildland fires Fossil fuel use
Page 11 – October 9, 2015 [Gong 2004, Monahan et al. 1986] Emissions of Pollutants and Precursors – sea-salt
Page 12 – October 9, 2015 Marticorena and Bergametti [1995] Emissions of Pollutants and Precursors – soil dust Ideal Threshold Friction Velocity
Page 13 – October 9, 2015 Roughness Roughness Marticorena and Bergametti [1995] Soil Moisture Soil Moisture Fécan et al. [1999] Emissions of Pollutants and Precursors – soil dust Threshold Friction Velocity
Page 14 – October 9, 2015 r < 20 m Marticorena and Bergametti [1995] Emissions of Pollutants and Precursors – soil dust Horizontal and Vertical Fluxes
Page 15 – October 9, 2015 Gas Phase Chemistry
Page 16 – October 9, 2015 Gas-Phase Chemistry, SOA formation (ADOM-II Mechanism, Odum or Jiang SOA approach, Vectorized Young&Boris Algorithm) Inorganic gas-phase processes usually included (Troposphere): NO 2 - NO - O 3 cycle. NO 3 - N 2 O 5 - HNO 3 reactions (NO x Termination) OH - HO 2 - H 2 O 2 cycle (including H 2 O path!) HONO, HNO 3, HNO 4 formation and cycling SO 2, CO oxidation by OH A look at some of these reactions: Gas-phase chemistry mechanisms
Page 17 – October 9, 2015 Aerosols Dynamics
Page 18 – October 9, 2015 Aerosol Size Representations Flexible model structure Multi-components Simulations Physically based size distribution Numeric diffusion for particle growth Computational intensive (large bin no.) Flexible model structure Computationally fast Accuracy dependent on the form of the mode distribution functions Pre-defined size distributions
Page 19 – October 9, 2015 Clear Sky Dynamics Gas H 2 SO 4
Page 20 – October 9, 2015 Dry Deposition Land Use Category [EDC DAAC, 1 1 km] 15 Surface Types ADOM Scheme SO2 [Padro et al 1991] Gases Two-layer Scheme Dry dep. for surface layer Sedimentation for all layers [Zhang et al., 2000] Particles Dry Deposition and Sedimentation
Page 21 – October 9, 2015 Wet Processes
Page 22 – October 9, 2015 Key Features Major smog components: CO, O3, SO2, NOx, NOy, PAN PM (aerosol) components: Sulphate, Black carbon, Organic Carbon, Soil dust, Sea-salt and Nitrate PM2.5 and PM10 AOD – aerosol optical depth
Page 23 – October 9, 2015 Real Time Forecasts
Page 24 – October 9, 2015 GEM Version –DM v –PHY v 4.5 Vertical 58 layers up to 0.1 hPa Horizontal resolution 2 2 Time step – 30 min Year: 2010 GEM Configurations
Page 25 – October 9, 2015 CUACE/Dust Data Assimilation SDS Observations lidar Ground Obs. Satellite FY-2c Gong and Zhang 2007, ACP Dust Aerosol Assimilation
Page 26 – October 9, 2015 Comparisons of CUACE/Dust forecasting results for 10 April 2006 with and without data assimilation. The symbols of “S”, “$”, “§”, “&” indicate floating dust, blowing dust, SDS, severe SDS, respectively, obtained from surface meteorological stations of CMA SDS Assimilation Results
Page 27 – October 9, 2015 Five Day Forecasts Results Online to be downloaded: –Gases: CO, O 3, SO 2 –Aerosol Species PM 10, PM 2.5 Sulphate PM 10 & PM 2.5 Soil Dust PM 10 & PM 2.5 More offline results available
Page 28 – October 9, 2015 Types of Results online Surface and 850 hPa concentrations; Cross section at three longitudes to track the vertical transports along the Pacific; Point vertical profiles to compare with station observations.
Page 29 – October 9, 2015 O3O3 O3O3
Page 30 – October 9, 2015 Dust
Page 31 – October 9, 2015 Vertical profiles
Page 32 – October 9, 2015 Near North America Middle Pacific Near East Asia
Page 33 – October 9, 2015 Data Fusion on O3 Simulations D. Tarasick
Page 34 – October 9, 2015 Data Fusion on O3 Simulations D. Tarasick
Page 35 – October 9, 2015 O 3 Reduction due to 20% Cuts in NOx and VOC in Asia (annual average)
Page 36 – October 9, 2015 Future Work
Page 37 – October 9, 2015 GEM-MACH Global Futures Evaluations against observations: surface, satellites; Interfaced with regional GEM-MACH to provide boundary and initial conditions; Data assimilation capacity for a better forecast; More......
Page 38 – October 9, 2015 Thanks!