Contribution from Natural Sources of Aerosol Particles to PM in Canada Sunling Gong Scientific Team: Tianliang Zhao, David Lavoue, Richard Leaitch,

NARCM NCEP

Aerosol Mass Balance Aerosol Mass Balance         ij TRANSPORT ij SURFACE ij CLEARAIR ij DRY ij INCLOUD ij BELOWCLOUDS ttttt tt    Gong et al. 2003, JGR CAM: A Size Segregated Simulation of Atmospheric Aerosol Processes for Climate and Air Quality Models 1.Module Development

Source Functions Sea-saltSea-salt Soil dustSoil dust DMS - SulphateDMS - Sulphate BC/OCBC/OC  Bio-mass burning

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

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

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

Global Budgets for the 1980s Biomass Burning Fossil Fuels 3 Natural Sources 1 Savannas 1 Tropical forests 1 Boreal & temperate vegetation fires 2 Agricultural fires 1 Domestic fuels TOTAL _ B.C. (Tg year -1 ) P.O.M. (Tg year -1 ) Liousse et al. (1996), 2 Lavoué et al. (2000), 3 Cooke et al. (1999) Source Functions – Bio-Mass

Boreal Forest Fire Emissions, 1998 Source Functions – BC/OC

Black Carbon, Canada 30% Source Functions – BC/OC

90% Particulate Organic Carbon, Canada Source Functions – BC/OC

nM January Source Functions – DMS

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

Results – Dust Aerosols

Results – Soil Dust

POM Concentrations

Results – BC

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

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 %  g m -3

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

Other Natural Aerosols DMS (Oceanic & Land)  DMS+OH  SO 2  H 2 SO 4 Biogenic Emission  Secondary Organic Aerosol (SOA) Volcanoes  SO 2 and sulphate

Interannual Variations – Soil Dust

Black Carbon, Canada 30% Interannual Variations – Bio-Mass

90% Interannual Variations – Bio-Mass Particulate Organic Carbon, Canada

SURFACE OZONE ENHANCEMENTS CAUSED BY ANTHROPOGENIC EMISSIONS FROM DIFFERENT CONTINENTS GEOS-CHEM model, July 1997 North America Europe Asia Li et al. [2001]

Inter-continental Transport How much background level of ozone can be attributed to inter-continental transport in Canada? How much background level of PM in Canada can be attributed to inter-continental transport? What is the impact of economic developments in other continents to Canadian AQ?

Intercontinental transport and Climatic effects of Air Pollutants (ICAP) To conduct an assessment of long-range transport and impacts on the regional climate. (1) the role of anthropogenic emissions originating from outside North America in U.S. air quality and the global distribution of air pollutants; (2) the role of anthropogenic emissions from the U.S. and other developed countries in determining air quality in other regions; (3) the contributions of important source categories (e.g., biomass burning, utility sector, transportation sector) and their pollutant emissions (e.g., ozone and PM precursors, black carbon, methane) to regional air quality and climate.

Multiyear simulation – more scenarios – High and low contributions Large domain – including Sahara desert Comparison with observations Separate natural and anthropogenic simulations Multi-frame work and pollutants – GEM/AQ, AURAMS, …. – CO, O 3, BC/OC, …. Future Work

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

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