One of the objectives of the National Polar-orbiting Operational Environmental Satellite System (NPOESS) program is to continue the long-term data set of total column ozone measurements from the Total Ozone Mapping Spectromenter (TOMS) systems while providing the increased accuracy and precision required by the NPOESS Integrated Program Office (IPO). In developing an Ozone Mapping and Profiler Suite (OMPS) sensor-algorithm system to meet the NPOESS requirements, we systematically analyzed the performance of the TOMS system and determined that it provided a strong starting point for the design of the OMPS system. In fact, our analysis showed that modern TOMS systems meet the NPOESS accuracy requirements for retrievals below 475 Dobson Units (DU). However, the NPOESS precision requirements are met only for retrievals below 225 DU. In order to meet the NPOESS accuracy and, particularly, precision requirements for all total column ozone amounts, we identified areas where improvements in the heritage design lead to the improved performance needed for the OMPS system. Simulations performed using the OMPS system design confirm that the algorithm enhancements, coupled with improvements contained in the OMPS sensor, provide performance that meets the NPOESS IPO requirements.
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