Nimbus7/TOMS March 1999 These data files are from the Nimbus-7/TOMS instrument launched on October 1978 which operated continuously for 14.5 years until TOMS failed on May 6, 1993. The orbit of Nimbus 7 was sun-synchronous with an original equator crossing time very near noon. Over the years of operation the equator crossing time drifted to 10:40 am. Complete global measurements were made of ozone every day except in regions not lit by the sun (polar winter). During approximately the first two years of operation TOMS was turned off one day in four in order to conserve power. Information files: NIMBUS7_USERGUIDE.PDF Contains details about the Nimbus7/TOMS science algorithms, data products and data file formats. PDF files can be read with Adobe Acrobat software, which may be obtained free from http://www.adobe.com Data availability: At this anonymous ftp site we offer Version 7 ozone, reflectivity, aerosol and uv data from the Nimbus7 TOMS. Additional subsets of data available at this site are shown below in the "Data files" directory paths. Images of ozone, aerosol, reflectivity and uv data are offered at the paths shown under "Image files". Version 7 ozone data, in the same ASCII format, are also available on CD-ROM from the Goddard DAAC http://daac.gsfc.nasa.gov/ Data files: data/aiYYYY (YYYY=1978-1993) data/ozYYYY data/reflYYYY data/uvYYYY data/monthly_averages data/overpass data/zonal_means Image files: images/global/yYYYY (YYYY=1978-1993) (ozone data) images/aerosol/yYYYY images/reflectivity/yYYYY images/uv/yYYYY For more information see the 1README text in the data and images subdirectories. If these data are downloaded and used in publication, please give proper credit to the NASA/GSFC TOMS Ozone Processing Team. For more information concerning the Nimbus 7 TOMS data files, contact Dr. Richard D. McPeters Code 916 NASA Goddard Space Flight Center Greenbelt, MD 20771 mcpeters@wrabbit.gsfc.nasa.gov