Randall Martin

1
Evaluating NOx Emission Inventories in North
America and Beyond
Randall Martin Aaron Van Donkelaar
Yongtao Hu Armistead Russell
Chris Sioris Kelly Chance
Tom Ryerson
Jack Dibb
Bill Brune
Ron Cohen
UC Berkeley
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Cloud-filtered Tropospheric NO2 Columns Observed
from the SCIAMACHY Satellite Instrument (Data ?
ICARTT)
May-Oct 2004
detection limit
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EMIS Emissions Mapping Integration
ScienceOptimize North American NOx Emissions
SCIAMACHY NO2 Columns
NOx Emissions (SMOKE/G.Tech)
Aug 2004
May-Oct 2004
A priori emissions (SMOKE/Russell)
1011 molec N cm-2 s-1
1015 molecules cm-2
GEOS-CHEM
CMAQ
Error weighting
Top-Down Emissions
A posteriori emissions
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North American NOx Emissions (May
October)Largest Change in Northeastern US Coast
GEOS-CHEM (NAPAP Scaled to 1998)
SCIAMACHY (2004)
SCIAMACHY - NAPAP
1011 atoms N cm-2 s-1
1011 atoms N cm-2 s-1
1011 atoms N cm-2 s-1
r2 0.85
7.6 Tg N
0.8 Tg N
8.4 Tg N
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Evaluate Top-Down and Bottom-Up NOx
InventoriesConduct GEOS-CHEM Simulation For Each
InventorySampled GEOS-CHEM Along Flight Tracks
Simulation with SCIAMACHY Original NOx Emission
Inventory
?NOx (ppbv)
?HNO3 (ppbv)
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P-3 Measurements Support Top-Down InventoryDC-8
Measurements Inconclusive
New England
New England Gulf
Remote
In Situ
GEOS-CHEM (Top-Down)
GEOS-CHEM (Bottom-up)
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Major Discrepancy in NOx Emissions from Megacities
48 Tg N
May-Oct 2004
48 - 38 Tg N
GEIA 1998
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SCIAMACHY Shows Elevated NOx Export from North
America
SCIAMACHY NO2 (1015 molec cm-2)
May-Oct 2004
GEOS-CHEM NO2 (1015 molec cm-2)
May-Oct 2004
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Explained by Model Bias in Upper Tropospheric NOx
West of -60 degrees lon, land
East of -60 degrees lon, ocean
GEOS-CHEM NO2 Cohen NO2
GEOS-CHEM low by factor of 2 in column
GEOS-CHEM low by 7.5 in column
GEOS-CHEM NO Brune NO
Errorbars Show 17th and 83rd percentiles