Summary

Description

The second release of Version 003 OMI/Aura Level-2 Total Column Ozone Data Product OMDOAO3 is now available ( http://disc.gsfc.nasa.gov/Aura/OMI/omdoao3_v003.shtml ) from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for the public access. The data was processed in late 2011 using Algorithm or PGE version 1.2.3 and released in March 2012. OMI provides two total column ozone products based on two different algorithms. This level-2 global total column ozone product at the pixel resolution (13x24 km at nadir), is based on the Differential Absorption Spectroscopy (DOAS) fitting technique that essentially uses the OMI visible radiance values between 331.1 and 336.1 nm. In addition to the total ozone column this product also contains some auxiliary derived and ancillary input parameters e.g. ozone slant column density, ozone ghost column density, air mass factor, scene reflectivity, radiance over the DOAS fit window, root mean square of DAOS fit, cloud fraction, cloud radiance, cloud pressure, terrain height, geolocation, viewing angles and quality flags. (The shortname for this Level-2 OMI total column ozone product is OMDOAO3) The lead scientist for this product is Dr. J. Pepijn Veefkind (Veefkind@knmi.nl). OMDOAO3 product files are stored in Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (approx 53 minutes) and is roughly 10.978 MB in size. There are approximately 14 orbits per day thus the total data volume is approximately 150 GB/day. A list of tools for browsing and extracting data from these files can be found at: http://disc.gsfc.nasa.gov/Aura/tools.shtml A 'Readme' document containing brief algorithm description and known data quality related issues and file spec are provided by the OMDOAO3 Algorithm lead (see http://disc.gsfc.nasa.gov/Aura/OMI/omdoao3_v003.shtml).