Factors Influencing Agreement between OMI-based Ozone and NO2 Products and Ground-based Instrumentation during DISCOVER-AQ (July 2011, Maryland): Site Variability and Meteorology
Abstract
The Pandora spectrophotometric column measurements of ozone and NO2 with OMI overpass comparisons are presented for 11 Maryland, USA, sites that operated in July 2011 in the DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) aircraft and ground campaign. In general, total ozone agreement between the Pandora and satellite is within 4%, with larger deviations present on very cloudy days. Both Pandora and OMI total ozone agree within a few percent of the integrated sonde total column ozones. In contrast, the TTOR tropospheric ozone column to 200 hPa, that is based on OMI and MLS differences, averages 20% offsets, usually too low, over Beltsville, 15 km from Washington, DC, and the Edgewood sampling site, 25 km northeast of Baltimore, where bay breeze is one factor enhancing lower tropospheric ozone. Site to site differences in NO2 column agreement are prominent, with the few rural sites displaying smaller offsets between OMI and Pandora. However, detailed examination of days with the largest discrepancies (greater than 30%) reveals that the ground NO2 measurement can be very sensitive to scattered clouds and low-lying aerosols. Implications for the use of satellite products by Air Quality decision-makers are discussed.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.A13N..05T
- Keywords:
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- 0345 ATMOSPHERIC COMPOSITION AND STRUCTURE / Pollution: urban and regional;
- 0368 ATMOSPHERIC COMPOSITION AND STRUCTURE / Troposphere: constituent transport and chemistry;
- 0394 ATMOSPHERIC COMPOSITION AND STRUCTURE / Instruments and techniques;
- 1640 GLOBAL CHANGE / Remote sensing