TOP-DOWN CONSTRAINTS ON EMISSION INVENTORIES OF OZONE PRECURSORS

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TOP-DOWN CONSTRAINTS ON EMISSION INVENTORIES OF
OZONE PRECURSORS

Daniel Jacob Dorian Abbot Paul Palmer
Kelly Chance Thomas Kurosu
Randall Martin
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HOW DO WE EVALUATE AND IMPROVE BOTTOM-UP
INVENTORIES?
Surface NOX

• Global NOx Emissions (Tg N yr-1)
• Fossil Fuel (20-33)
• Biomass Burning (3-13) Soils (4-21)
• Here in Tg N yr-1 (based on)
• Fossil Fuel 24 (GEIA)
• Biomass Burning 6 (Logan/Duncan)
• Soils 5 (Yienger and Levy)

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TOP-DOWN INFORMATION FROM THE GOME SATELLITE
INSTRUMENT

• Operational since 1995
• Nadir-viewing solar backscatter instrument
  (237-794 nm)
• Low-elevation polar sun-synchronous orbit, 1030
  a.m. observation time
• Spatial resolution 320x40 km2, three cross-track
  scenes
• Complete global coverage in 3 days

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USE GOME MEASUREMENTS TO RETRIEVE NO2 COLUMNS TO
MAP NOx EMISSIONS
Retrieval Summary
Spectral Fit (423-451 nm)
GOME
Total Slant Column
Remove Stratosphere
Tropospheric Slant Column
Tropospheric NO2 column ENOx
Calculate AMF
Tropospheric Column
BOUNDARY LAYER
Martin et al., 2002
NO2
NO
NO/NO2 ? ? W ALTITUDE
lifetime hours
HNO3
Emission
NITROGEN OXIDES (NOx)
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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 SURFACE INVENTORY 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
Martin et al., 2003
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TOP-DOWN INFORMATION FROM GOME REDUCES ERROR IN
NOX EMISSION INVENTORY
Bottom-up error ?a Mean2.0
Top-down error ?t Mean2.0
Mean1.6
Martin et al., 2003
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OPTIMIZED SURFACE NOX EMISSIONS
37.7 Tg N yr-1
36.4 Tg N yr-1
Martin et al., 2003
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A POSTERIORI MINUS A PRIORI EMISSIONS
Martin et al., 2003
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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 (in progress using
GBEIS)
Abbot et al., 2003