Monitoring of Transatlantic Long Range Transport of Tropospheric NO2

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Monitoring of TransatlanticLong Range Transport
of Tropospheric NO2 Observation and Simulation

• Bas Mijling
• Bart Dils
• Ronald van der A
• Ruud Dirksen

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• Part 1
• Observation

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Observation LRT with satellites

• Why tropospheric NO2?
• Relatively easy to measure
• Relation with tropospheric O3
• Why OMI?
• Daily global coverage high resolution
• Why Atlantic region?
• Predominant westerly winds transport air
  pollutants from East US to West Europe

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Basic mechanism of long range transport
East Asian outflowof tropospheric NO2observed
by OMI26 May 2007
1. Rapid uplift
2. Fast horizontal transport
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Shielding effects of clouds
Surf. albedo 0.02
Cloud at 800 hPa
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Event I Transatlantic NO2 transport
2-12-2005
3-12-2005
5-12-2005
4-12-2005
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Event II Transatlantic NO2 transport
22-12-2005
23-12-2005
25-12-2005
24-12-2005
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Event III Backflow from Europe
6-2-2007
7-2-2007
9-2-2007
8-2-2007
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Event IV Forest fires on the Canaries
29-7-2007
30-7-2007
1-8-2007
31-7-2007
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Data quality OMI collection 3

• Level 0-1 Improved dark current correction
• Level 1-2 Averaged solar irradiance spectrum

Collection 2
Collection 3

• Improved signal to noise ratio (noise floor now
  at 0.2 1015 molec/cm2)
• No cross-track gradient (no artifacts at
  overlapping tracks)
• Still some striping problem (to be corrected for
  with filter)

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• Part 2
• Observation Simulation

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OMI observation / FLEXPART simulation
Flexpart, 14 Jan 2007
OMI, 14 Jan 2007
OMI less sensitive to NO2 in lower troposphere
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OMI observation / FLEXPART simulation
Flexpart, 6 Jan 2007
OMI, 6 Jan 2007
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http//www.temis.nl/lrt

• Height dependency
• Frequency (seasonality)
• Quantify transport

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Future activities

• Reprocessing OMI data using collection 3
• Implementation destriping filter
• New data-format (HDF5 instead of ASCII)
• Other areas (East Asia, South Africa, )
• Other satellite instruments (GOME-2)
• Quantifying transport
• Correlation with background stations

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Thank you for your attention!
www.temis.nl/lrt
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