Challenges in Creating Trend Quality Data from Satellites

The Solar Backscatter Ultraviolet (SBUV) series consisting of some 8 separate instruments flown on NASA and NOAA satellites over a period of 40 years, plus 8 flights of a similar instrument on the Space Shuttle to calibrate the satellite instruments, represent perhaps one of the largest investments this nation has made in measuring long-term changes of an important atmospheric variables from space- in this case the stratospheric ozone column and its vertical distribution. The plan is to continue the ozone monitoring program using the Ozone Mapper and Profiling Suite (OMPS) of instruments on the NPP and NPOESS satellites. In this presentation I will discuss numerous issues and challenges that we had to face in creating an accurate time series from these data. As new instruments of better accuracy and scope get launched and as our capability to model the radiation measured by the satellite instruments improves they reveal issues that require updating the previous data record. Our experience suggests that this process must be repeated every 5 years to maintain and improve long-term accuracy and data consistency.