Using Space-based Observations to Improve Model Calculations of Transboundary Pollution Transport

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Using Space-based Observations to Improve Model
Calculations of Transboundary Pollution Transport

Randall Martin Aaron Van Donkelaar
Daniel Jacob Dorian Abbot
Kelly Chance Chris Sioris
Arlene Fiore
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Transport Pattern on High-Ozone Days
90th percentile O3 concentrations for summers
1991-1995 and mean 850hPa winds on days when O3
gt 90th percentile
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Top-down Information from the GOME Satellite
Instrument

• Launched in 1995
• Spatial resolution 320x40 km2
• Complete global coverage in 3 days

Spectral Fit (UV/Vis)
Total HCHO NO2 Slant Column
Remove Stratosphere
Tropospheric NO2 Slant Column
Calculate AMF
Tropospheric HCHO NO2 Column
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Tropospheric NO2 and HCHO Closely Related to
Surface NOx and VOC Emissions
Tropospheric NO2 column ENOx Tropospheric HCHO
column EVOC
Boundary Layer
CO
NO2
NO
HCHO
hours
NO/NO2 ? ? W ALTITUDE
OH
HO2
hours
VOC
hours
HNO3
Emission
Emission
Nitrogen Oxides (NOx)
Volatile Organic Compounds (VOC)
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GOME HCHO COLUMNS SHOW SEASONAL VOC EMISSIONS
GOME GEOS-CHEM (GEIA)
GOME GEOS-CHEM (GEIA)
MAR
JUL
APR
AUG
MAY
SEP
JUN
OCT
-0.5 0 1016
molec cm-2 2.0 2.5

Agreement in general pattern, regional
discrepancies point to need for improving
GEOS-CHEM isoprene emissions
Abbot et al., 2003
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GOME Tropospheric NO2
GEOS-CHEM Tropospheric NO2
r0.75 bias 5
Martin et al., 2003
1015 molecules cm-2
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STRATEGY OPTIMIZE INVENTORIES USING A PRIORI
BOTTOM-UP AND GOME TOP-DOWN INFORMATION
Top-down emissions
A priori emissions
A posteriori emissions
Top-down errors
A priori errors
GOME
GEOS-CHEM
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Investigate Discrepancies with Bottom-up
Inventories
AUG 2002
Martin et al., 2003
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Surface ozone concentrations are sensitive to the
ratio of NOx emissions to VOC emissions
(ppbv)
NOx-Saturated
NOx-Sensitive
Sillman and He, 2002
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Tropospheric HCHO/NO2 Column Ratio Is an
Indicator of the Sensitivity of Afternoon Surface
Ozone to NOx and VOC Emissions in a Well-mixed
EnvironmentGEOS-CHEM Model Calculation For
Polluted Regions, Mar-Nov
NOx Saturated
NOx Sensitive
Martin et al., 2004
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GOME Satellite Observations of Ozone-NOx-VOC
Sensitivity
Martin et al., 2004
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SCIAMACHY Provides Much Finer Spatial Resolution
(30 km x 60 km)
OMI (13 km x 24 km) Will Be Launched in June
AUG 2002
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MODIS Optical Depth for July 2002
Aaron Van Donkelaar