This data product contains TOMS/Nimbus-7 UV-B Erythemal Local Noon Irradiance Daily L3 Global 1x1.25 deg Lat/Lon Grid Version 8 data in ASCII format. 

The Total Ozone Mapping Spectrometer (TOMS) Version 8 Daily Gridded Data consist of daily, global coverage of total column ozone, aerosol index, Lambertian effective reflectivity(Rayleigh corrected) and surface UV-B Erythemal irradiances. 

Four TOMS ... instruments have been successfully flown on the following satellites: Nimbus-7 (Nov. 1978 - May 1993), Meteor-3 (Aug. 1991 - Dec. 1994), Earth Probe (July 1996 - current), and ADEOS (Sep. 1996 - June 1997).

Earth Probe, Meteor-3 and Nimbus-7 data are currently reprocessed using the Version-8 algorithm (http://toms.gsfc.nasa.gov/version8/v8toms_atbd.pdf) . These Version-8 data are archived at NASA Goddard Earth Sciences Data and Information Services Center (GES DISC).

The total ozone, aerosol index, reflectivity data and UV-B Erythemal irradiances are mapped to a global grid of size 180 x 288 with a Lat/Lon resolution of 1.00 x 1.25 degrees. These data are also stored in the EOS Version of Hierarchical Data Format (HDF-EOS). HDF was developed by the National Center for Supercomputer Applications (NCSA) at the University of Illinois at Urbana-Champaign.

The GES DISC maintains an online Web-based system (Giovanni) for previewing the data, subsetting in ASCII format, and downloading the data and images. The URL for Giovanni is http://giovanni.gsfc.nasa.gov/.

The Level-2 data at instrument resolution(approx 50km x 50km pixel at nadir, in HDF5 EOS format) are also available from the GES DISC. 

For more information regarding TOMS or other DAAC data sets please visit the GES DISC Home Page at http://disc.sci.gsfc.nasa.gov/acdisc/ , or contact the DISC Help Desk at: 

GES DISC Help Desk
NASA Goddard Space Flight Center
Code 610.2
Greenbelt, MD 20771

gsfc-help-disc@lists.nasa.gov

TOMS data are produced by the Laboratory for Atmospheres at NASA Goddard Space Flight Center (Code 613). The Version-8 Algorithm Theoretical Basis Document (ATBD) is available from the TOMS site http://toms.gsfc.nasa.gov/version8/v8toms_atbd.pdf

For detailed information about the TOMS instrument, data, and ozone see the TOMS official Home Page at: http://toms.gsfc.nasa.gov/.