1. Modeling BC Sources and Sinks - research plan Charles Q. Jia and Sunling Gong University of Toronto and Environment Canada @ 1 st annual NETCARE workshop

2. Outline Objective and approach GEM-MACH Canadian Aerosol Module (CAM) An example: Arctic BC seasonal variation

3. Objective and Approach 1.To enhance the capacity of GEM-MACH in forecasting BC in the Arctic incorporating the science from NETCARE to better represent BC processes in the CAM (e.g. BC aging) using the measurement data from NETCARE to validate the model 2.To better understand the sources and sinks of BC in the Arctic region using the enhanced GEM-MACH focusing on relative contributions of various sources (e.g. natural vs. anthropogenic) and long- range transport

4. GEM: Global Environmental Multi-scale Model – An operational numerical weather forecasting model – Developed by Meteorological Service of Canada (MSC) [Cote et al., 1998; Yeh et al., 2002]. MACH: Two air quality modules (ADOM and CAM) – The Acid Deposition and Oxidants Model (ADOM) is an integrated gas-phase chemistry module [Venkatram et al., 1988]. – The Canadian Aerosol Module (CAM) simulates physical and chemical processes of size-resolved aerosol in the atmosphere [Gong et al., 2003] GEM-MACH Global Environmental Multiscale Modeling Air Quality and CHemistry

5. GEM-MACH Structure SMOKE Regional Data Canada & US Gas Phase Chemistry CAM Canadian Aerosol Module GEM Meteorology Transport Emission InterfaceChemistry Interface Global Emissions

6. Canadian Aerosol Module (CAM) Simulates physical and chemical processes of aerosols in the atmosphere [Gong et al., 2003] Emissions, in-cloud and below-cloud scavenging, dry deposition, coagulation, condensation, nucleation et al. Size-resolved: 12 particle size bins (0.01 to 41 μm in diameter) Multi-component: 5 species (BC, OC, sulphate, sea salt, soil dust)

7. An example: importance of depositional processes in seasonal variation of the Arctic BC (Huang L. et al., JGR, V115, D17207, 2010)

8. Seasonal Variation of the Arctic BC Model Simulation vs. Observation (surface BC) 8 BC (pptm) Obs. (Sharma et al., 2006) 11-model predictions [Shindell et al., 2008] Barrow Zeppelin Alert Red- IMPROVE site at Barrow (1996-1998)

9. 9 Enhanced In-cloud Scavenging Parameterization Original (empirical) [Giorgi and Chameides, 1986] Enhanced F – GEM cloud cover P – GEM precipitation

10. Effects of Enhanced Parameterization of In-cloud Scavenging 10 Correlation Coefficient, R beforeafter Alert0.490.91 Barrow-0.510.58 Zeppelin-0.130.77 Observations at Zeppelin: Eleftheriadis et al., 2009

11. 11 Enhanced below-cloud scavenging parameterization Original Valid when Re < 0.1 Enhanced, (any Re) Re – [Feng, 2007]

12. 12 Effects of Enhanced Parameterization of Below-cloud Scavenging Correlation Coefficient, R before after Alert 0.910.95 Barrow 0.580.50 Zeppelin 0.770.81

13. Thanks!