HR: 1340h
AN: A33A-0136    [Abstracts]
TI: First Global Maps of Stratospheric and Tropospheric NO$_{2}$ from OMI
AU: * Celarier, E A
EM: celarier@jwocky.gsfc.nasa.gov
AF: SGT, Inc., 7701 Greenbelt Rd Ste 400, Greenbelt, MD 20770 United States
AU: Bucsela, E J
EM: bucsela@redwind.gsfc.nasa.gov
AF: Goddard Earth Sciences Technology Center, University of Maryland Baltimore County 1000 Hilltop Circle, Baltimore, MD 21250 United States
AU: Wenig, M O
EM: wenig@hyperion.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 916.0, Greenbelt, MD 20771 United States
AU: Gleason, J F
EM: james.f.gleason@nasa.gov
AF: NASA Goddard Space Flight Center, Code 916.0, Greenbelt, MD 20771 United States
AU: Veefkind, J P
EM: veefkind@knmi.nl
AF: Royal Dutch Meteorological Institute, PO Box 201, De Bilt, NL 3730 AE Netherlands
AU: Boersma, K F
EM: boersma@knmi.nl
AF: Royal Dutch Meteorological Institute, PO Box 201, De Bilt, NL 3730 AE Netherlands
AB: The Ozone Monitoring Instrument (OMI) was launched successfully in July 2004, as one of four instruments on the EOS Aura satellite. OMI is an imaging spectrometer with a small pixel size (13km x 24km to 13km x 128km). The instrument's swath width and sun-synchronous orbit gives full global, high-resolution coverage every 24 hours. OMI-measured radiances are used to retrieve column densities of critical trace gases, including formaldehyde, BrO, SO$_{2}$ and NO$_{2}$. In addition, OMI measures aerosol optical properties and cloud fraction and height. We present the first results from the OMI operational NO$_{2}$ algorithm and demonstrate its ability to retrieve the tropospheric and stratospheric components of NO$_{2}$. The DOAS method is used to determine slant column densities, and initial air mass factors are used to give initial estimates of the vertical column densities. Vertical column densities from up to 15 consecutive orbits are collected, and a spatial filtering technique is applied to extract the synoptic-scale features characteristic of the stratospheric field. We take smaller-scale features to be evidence of tropospheric excess NO$_{2}$, and apply an air mass factor appropriate to polluted conditions, to obtain an improved retrieval of the NO$_{2}$ total vertical column density. We describe the assumptions underlying the algorithm in detail, and show global maps of NO$_{2}$ vertical column densities, based on the first operational data from OMI.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0340 Middle atmosphere--composition and chemistry
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting