A New Homogenized Gridded Total Ozone Mapper Data Set

Total column ozone data from the Nimbus-7's Total Ozone Mapping Spectrometer, AURA's Ozone Monitoring Instrument (OMI), and NPP's Ozone Mapping and Profiler Suite (OPMS) Nadir Profiler instruments have been newly reprocessed with the Version 9 ozone retrieval algorithm. The results of the new datasets show that the agreement with the SBUV-type instruments and the Dobson/Brewer ground-based network are biased approximately 2% high. We propose to normalize the mapper data to the SBUV record thus correcting for absolute bias as well as scan position bias (another 1-2%) and any anomalous trends. The SBUV Merged Ozone Data (MOD) is the reference ozone trend data set spanning from 1979 to the present. The agreement of MOD to the ground-station network is on the order of +/- 1% with no bias. The corrected data set would be a 1x1 degree daily map. Correcting the mapper data to this type of accuracy would improve our understanding of the ozone layer. The potential applications of this product are: a more accurate overpass data set, a more accurate estimation of the size and depth of the Antarctic ozone hole, better trends for specific site locations and less errors during times of high aerosol loading. This method of correction will also be applied to Earth-Probe and Meteor-3 TOMS in the future to possibly allow those data to be used in ozone trend studies.