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Nesting GEOS-CHEM with a regional air pollution model for Greece

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Maria Tombrou, Elissavet Bossioli, Anna Protonotariou,

Elena Flocas and Aggeliki Dandou

University of Athens

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Christos Giannakopoulos

National Observatory of Athens

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2ND GEOS-CHEM users Meeting

University of Athens

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What we Know

  • Critical factors for high levels of photochemical pollutants in the GAA:
    • poor ventilation
    • frequent appearance of the sea breeze
    • intense solar irradiation
    • intense anthropogenic activities

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  • The long range transport of ozone precursors, from the Western European continent over the Eastern Mediterranean, contributes significantly in high ozone concentrations.

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What we don’t know

  • It is unclear yet which mechanism contributes the most

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  • the reasons for underestimating ozone concentration during episodes

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2ND GEOS-CHEM users Meeting

University of Athens

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Emission inventory (point sources)�SO2 (moles/h)

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2ND GEOS-CHEM users Meeting

University of Athens

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Emission inventory (area anthropogenic)

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2ND GEOS-CHEM users Meeting

NOX (moles/h/4km2)

University of Athens

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Emission inventory (biogenic)

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2ND GEOS-CHEM users Meeting

Isoprene (kg/h/36km2) Terpenes (kg/h/36km2)

University of Athens

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Numerical experiments (MM5/UAM)

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  • Base case: only anthropogenic emissions

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  • Numerical experiments:
    • Biogenic emissions

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    • VOC’s speciation in urban areas and aged plumes

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    • Background O3 concentration levels

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    • Various sets of meteorological fields (different nesting, urban sector effects on the wind speed and diffusion coefficient, increase the depth of first layer)

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2ND GEOS-CHEM users Meeting

University of Athens

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Diurnal variation of O3 concentrations at a suburban station of Athens on 14.09.94

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2ND GEOS-CHEM users Meeting

University of Athens

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Diurnal variation of O3 �by GEOS – CHEM over Greece (1-6) 14.09.94 �

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2ND GEOS-CHEM users Meeting

FIG. 7 : Diurnal variation of O3 concentrations as calculated by

GEOS –CHEM over Greece (1-6) on 14.09.94.

FIG. 7 : Diurnal variation of O3 concentrations as calculated by

GEOS –CHEM over Greece (1-6) on 14.09.94.

FIG. 7 : Diurnal variation of O3 concentrations as calculated by

GEOS –CHEM over Greece (1-6) on 14.09.94.

FIG. 7 : Diurnal variation of O3 concentrations as calculated by

GEOS –CHEM over Greece (1-6) on 14.09.94.

FIG. 7 : Diurnal variation of O3 concentrations as calculated by

GEOS –CHEM over Greece (1-6) on 14.09.94.

FIG. 7 : Diurnal variation of O3 concentrations as calculated by

GEOS –CHEM over Greece (1-6) on 14.09.94.

University of Athens

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24.06.98

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2ND GEOS-CHEM users Meeting

surface

700mb

500mb

850mb

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24 6

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2ND GEOS-CHEM users Meeting

GEOS – CHEM results

24 6 98

University of Athens

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Concentrations of O3 (μgr/m3) �at 15:00LST�

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2ND GEOS-CHEM users Meeting

Boundary inflow from GEOS-CHEM

Boundary inflow constant

University of Athens

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Concentrations of O3 (μgr/m3) �at 15:00LST

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2ND GEOS-CHEM users Meeting

Boundary inflow from GEOS-CHEM

Boundary inflow constant

University of Athens

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Future work

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2ND GEOS-CHEM users Meeting

  • Develop the nesting capability for the Mediterranean region (1ox1o)

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  • Insert EMEP emissions over Europe and the new inventory of Greece (at the appropriate levels)

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  • Link GEOS-CHEM with CAMx; UAM

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  • Perform O3 sensitivity runs

University of Athens