The second Release of Collection 003 of OMI/Aura Global Gridded Nitrogen Dioxide Product 'OMNO2G' is now available, from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC). http://disc.sci.gsfc.nasa.gov/Aura/data-holdings/OMI/omno2g_v003.shtml

(The shortname for this Level-2G Global Gridded Nitrogen Dioxide Product is OMNO2G_V003) 
     
Nitrogen dioxide is an important chemical species in both the
stratosphere, where it plays a key role in ozone chemistry, and in the
troposphere, where it is a precursor to ozone production. In the
troposphere, it is produced in various combustion processes and in
lightning and is an indicator of poor air quality.

The algorithm leads for the NO2 products OMNO2 and OMNO2G are NASA OMI
scientist Dr. Nickolay Krotkov and KNMI Scientist Dr. Pepijn Veefkind.
            
OMNO2G data product is a special Level-2 Gridded Product where pixel
level data are binned into 0.25x0.25 degree global grids. It contains
the data for all L2 scenes that have observation time betweeen UTC
times of 00:00:00 and 23:59:59.9999. All data pixels that fall in a
grid box are saved Without Averaging. Scientist can apply data
filtering scheme of their choice and create new gridded products. The
GES DISC developed interactive tool Giovanni ( http://giovanni.gsfc.nasa.gov/ ) 
provides on-line web based capabilities to browse and explore these data.

The OMNO2G data product contains almost all parameters that are
contained in OMNO2 product. OMNO2G data are stored in EOS Hierarchical
Data Format (HDF-EOS5). Each file contains data from the day lit
portion of the orbit (~14 orbits).  The average file size for the
OMNO2G data product is about 115 Mbytes.
     

Data Category Parameters:
      
The OMNO2G data file consists of a Grid Data Object which contains
complete information for each pixel binned into a grid.
      
      NO2 Parameters (and STD):
      Column Amount NO2, Column Amount NO2 Statosphere, 
      Column Amount NO2 Troposphere, Slant Column Amount NO2, Atmospheric Mass Factors,---
      
      Ancillary Data: Cloud Fraction (and STD), Cloud Pressure (and
      STD), Cloud Radiance Fraction Terrain Pressure, Terrain
      Reflectivity
                
      Quality Flags: VCD Quality Flags, Ground Pixel QualityFlags,
      Measurement QualityFlags Processing QualityFlags, Fit Quality
      Flags, Root Mean Square Error Of Fit

      Time and Geolocation Data: Time, Latitude, Longitude Solar
      Zenith Angle, Viewing Zenith Angle, Relative Azimuth Angle Line
      Number, Scene Number, Number Of Candidate Scenes