Analysis of A-Train Tropospheric NO2 and Aerosol Data
Pepijn Veefkind
OMI Tropospheric NO2 2005-2007Linear color scale from 0-1.3 1016 molecules/cm2
OMI Tropospheric NO2 2005-2007Linear color scale from 0-0.5 1016 molecules/cm2
Sources of NOx and Aerosol
Emission Source NOx Aerosol
Fossil Fuel Combustion x x
Biomass Burning x x
Desert Dust x
Sea Spray x
Lightning x
Biogenic x
Soils x
In Europe NOx is an important precursorfor ammonium nitrate particles
In Europe NOx is an important precursorfor ammonium nitrate particles
Total Emissions from of SOx and NOx in Europe for 1995
Data taken from Schaap et al.ACP 4, 857-874, 2004
OMI NO2 and MODIS AOT
Time period 2005-2007Gridded 1x1 degree
OMI Tropospheric NO2 MODIS AOT at 550 nm
West-EuropeEast EuropeMediterenean
Region Correlation Slope
West Europe 0.79 0.93 10-17
East Europe 0.58 1.68 10-17
Mediterenean -0.20 N/a
Total Emissions from of SOx and NOx in Europe for 1995
NOx SOx
Image from Schaap et al.ACP 4, 857-874, 2004In Eastern Europe more SOx is emitted per unit NOx,
leading to more aerosol mass per unit NOx and toa larger slope between the NO2 concentration and AOT
In Eastern Europe more SOx is emitted per unit NOx,leading to more aerosol mass per unit NOx and to
a larger slope between the NO2 concentration and AOT
Global Analysis
• OMI NO2 Domino Product monthly mean (regridded 1x1 degree)
• MODIS Aqua AOD at 550 nm monthly mean, (1x1 degree)
• Correlation calculated for 10x10 degree regions (max 100 points, at least 50 co-locations)
• Data is filtered for tropospheric NO2 larger than 5x1014 molec./cm2
• Data period 2005-2007
AOD
Trop. NO2
GOCART Model Data from the NASA GIOVANNI web site
Sulfate
Dust
Organic Carbon
MODIS Aqua
Correlation between NO2 and AOD
NW Europe E USA
Beijng E Coast Africa
Summary• High spatial resolution gridded data set of OMI
tropospheric NO2 data over Europe;
• Significant correlation between AOT and tropospheric NO2 is observed in both industrial and biomass burning regions.
• The slope between tropospheric NO2 and AOT is larger for East Europe as compared to West Europe, which may be explained by the difference of NOx and SO2 emissions;
• The combined analysis of AOD and tropospheric NO2
provide information on the aerosol sources.
Ground Based In-Situ Data
• LML Dutch air quality network, www.rivm.nl/lml• Regional, City and Street stations• Mean yearly value per station for 12:00 to 14:00 hrs
Comparison with the LML
Data from October 2004 to September 2005