For data processed prior to 1 May 2002, MOD07_L2 is impacted by use of an incorrect look-up table (LUT) in the regression portion of the profile algorithm. This was resolved in PGE03 v3.2.0 (containing MOD_PR07 v3.10), which was implemented on 1 May 2002; therefore, a correction is in place for MOD07 data processed after that date.

Information provided by Rich Hucek NASA/Goddard Space Flight Center


For data processed prior to 1 May 2002, the MOD07_L2 water vapor profile and total water vapor products should be considered invalid for any retrieval location where the total precipitable water vapor exceeds 7.0 centimeters (especially obvious at times over the African Sahara). In addition, the total precipitable water vapor in these products has a wet bias on the order of 10-20%. This notice extends to all affected MODIS products including MOD05_L2, the MODIS Water Vapor product, which contains a copy of the infrared total precipitable water from MOD07_L2, and the Atmosphere Level 3 Daily, 8-day and Monthly gridded products (MOD08_D3, MOD08_E3 and MOD08_M3, respectively). The infrared water vapor algorithms have not been corrected in order to maintain consistency in this first year of MODIS Collection 3 products. Spatial and temporal gradients are believed to be representative and useful. Corrections are in place for data processed after 1 May 2002.

Information provided by Suzanne Wetzel Seemann, Liam Gumley, and Paul Menzel, University of Wisconsin


The total ozone at a granule level compare favorably with GOES-8 retrievals over North America. The total ozone retrievals globally compare favorably with EP-TOMS, however future improvements are possible in the Antarctic, where the regression database is sparsely populated.

Information provided by Liam Gumley, University of Wisconsin and Paul Hubanks, Code 913, NASA/Goddard Space Flight Center