Contribution from Natural Sources of Aerosol Particles to PM in Canada Task Force on Measurements and Modelling TFMM 6th Meeting, Zagreb, Croatia 4th – 7th April 2005 Contribution from Natural Sources of Aerosol Particles to PM in Canada Sunling Gong Meteorological Service of Canada Meteorological Service of Canada Environment Canada

Acknowledgement CWS – Canada Wide Standard for partial financial support of this project.

Natural Components

Sea-salt Soil dust BC/OC DMS - Sulphate Source Functions Bio-mass burning Biogenic SOA DMS - Sulphate

Source – Soil Dust Ideal Threshold Friction Velocity Marticorena and Bergametti [1995]

Source – Soil Dust Threshold Friction Velocity Roughness Marticorena and Bergametti [1995] Soil Moisture Fécan et al. [1999]

Source – Soil Dust Horizontal and Vertical Fluxes r < 20 mm Marticorena and Bergametti [1995]

Source – Soil Dust Parameters Needed Soil Features Meteorology Roughness Texture (size distribution) Composition Land use Meteorology Wind speed Soil moisture

Source – Sea-salt By two mechanisms: [Monahan et al. 1986, Gong 2004]

Source – Bio-Mass Burning B.C. (Tg year-1) P.O.M. (Tg year-1) Global Budgets for the 1980s Biomass Burning 5.96 50.4 Savannas1 Tropical forests1 Boreal & temperate vegetation fires2 Agricultural fires1 Domestic fuels1 2.17 1.93 0.33 0.53 1.00 15.5 16.6 5.9 3.1 9.3 Fossil Fuels3 5.10 9.4 Natural Sources1 _ 7.8 TOTAL 11.06 67.6 1Liousse et al. (1996), 2Lavoué et al. (2000), 3Cooke et al. (1999)

Source – BC/OC Boreal Forest Fire Emissions, 1998

Source – BC/OC Black Carbon, Canada 30% 20,000 40,000 60,000 80,000 20,000 40,000 60,000 80,000 100,000 120,000 140,000 160,000 180,000 200,000 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 BC (t) 30% Black Carbon, Canada

Source – BC/OC Particulate Organic Carbon, Canada 90% POC (t) 250,000 250,000 500,000 750,000 1,000,000 1,250,000 1,500,000 1,750,000 2,000,000 2,250,000 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 POC (t) 90% Particulate Organic Carbon, Canada

NARCM NCEP

Aerosol Mass Balance ¶c ¶c ¶c ¶c ¶c = + + + ¶ t ¶ t ¶ t ¶ t ¶ t ¶c ¶c ij ij ij ij ij = + + + ¶ t ¶ t ¶ t ¶ t ¶ t TRANSPORT SURFACE CLEAR AIR DRY ¶c ¶c ij ij + + ¶ t ¶ t IN - CLOUD BELOW - CLOUDS Gong et al. 2003, JGR CAM: A Size Segregated Simulation of Atmospheric Aerosol Processes for Climate and Air Quality Models 1. Module Development

Results 1998 – BC/OC from biomass only 2001 – spring with all sources

Results – Dust Aerosols

Results – Soil Dust

POM Concentrations

Results – BC

Surface concentration (ng.m-3) Results –OC Surface concentration (ng.m-3) Organic Matter Summertime Concentrations Column loading (ug.m-2) Canadian Fires, 1998

Sulphate - May 1998

Sulphate - Aug 1998

OC/Sulphate Ratio May 1998

OC/Sulphate Ratio Aug 1998

BC/Sulphate Ratio May 1998

BC/Sulphate Ratio Aug 1998

Results – Sea-salt % Sea-salt to PM in East Canada – 2001 Spring mg m-3

Results – Sea-salt % Sea-salt to PM in West Canada – 2001 Spring mg m-3

Other Natural Aerosols DMS (Oceanic & Land) DMS+OH  SO2  H2SO4 Biogenic Emission  Secondary Organic Aerosol (SOA) Volcanoes SO2 and sulphate

Interannual Variations – Soil Dust

Interannual Variations – Bio-Mass 20,000 40,000 60,000 80,000 100,000 120,000 140,000 160,000 180,000 200,000 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 BC (t) 30% Black Carbon, Canada

Interannual Variations – Bio-Mass 250,000 500,000 750,000 1,000,000 1,250,000 1,500,000 1,750,000 2,000,000 2,250,000 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 POC (t) 90% Particulate Organic Carbon, Canada

Future Work Multiyear simulation – more scenarios High and low contributions Large domain – including Sahara desert Comparison with observations Separate natural and anthropogenic simulations Multi-frame work GEM/AQ, AURAMS, ….

Summary - 1 A frame work for studying the contributions of natural aerosols to the background PM in Canada has been established. Seal-salt and bio-mass burning contribute substantially to the background PM depending on time and locations.

Natural contributions have a large interannual variations. Summary - 2 Natural contributions have a large interannual variations. More simulations should been done to characterize the variations of these contributions as well as other natural components.