ACCURACY OF TOTAL OZONE RETRIEVAL FROM NOAA SBUTJ 2 MEASUREMENTS - IMPACT OF INSTRUMENT PERFORMANCE/

The National Oceanic and Atmospheric Administration/National Environme ntal Satellite Data and Information Service (NOAA/NESDIS) has been col lecting and evaluating the solar backscattered ultraviolet (SBUV/2) in strument data from NOAA 9 and NOAA 11 spacecraft since March 1985. Ove r 5 years (March 1985 to October 1990) of NOAA 9 (version 5.0) and ove r 4 years (January 1989 to June 1993) of NOAA 11 (version 6.0) reproce ssed data are now available to the scientific community to study geoph ysical phenomena involving ozone. This paper examines the impact of th e instrument performance on total ozone retrieval from the two instrum ents. We estimate that at the end of October 1990 the total postlaunch error for NOAA 9 due to instrument alone is -2.2%. A significant frac tion of this error (-1.9%) is due to diffuser degradation which is not accounted for in the version 5 reprocessing. The estimate for NOAA 11 total postlaunch instrument error, at the end of June 1993, is -0.4%.