Ozone Mapping and Profiler Suite Limb Profiler Calibration and Validation
The Ozone Mapping and Profiler Suite (OMPS) is a suite of instruments on the Suomi National Polar-orbiting Partnership (S-NPP) satellite that primarily measures Ozone in the atmosphere. It has 3 instruments associated with it, the Nadir Mapper, Nadir Profiler, and Limb Profiler. The Limb Profiler (LP) measures limb scattered radiances over both visible and ultraviolet wavelengths. In an effort to try to further calibrate and validate OMPS-LP ozone measurements, comparisons were made with measurements from the Microwave Limb Sounder (MLS) instrument on the Earth Observing System Aura (EOS Aura) satellite. MLS has been taking measurements since 2004, compared to OMPS having only been taking measurements since 2012, so MLS was viewed as the “standard” to compare to in this project. Comparisons were made on both daily and monthly bases for the entire lifetime of OMPS, and two different comparison methods were done: Zonal Means (both Daily and Monthly) and Collocation (Daily only).
For the Zonal Means, both data sets were averaged longitudinally to create the zonal mean, along with a 2 degree latitude bin to make the data easier to work with. From there, the OMPS data was splinned to bring it down to the resolution of the MLS data. Once this was done, the two data sets could be compared 1 to 1 to create residual maps and bias maps. This was done for every day that both instruments took sufficient data and as a monthly average. Correlations were made from the resulting maps.
For the Collocation comparisons, for any given day, all instances where both satellites viewed any 1 degree by 1 degree latitude-longitude bin within a half hour of each other was taken into account. From here, the same splinning process was done on the OMPS data to bring it to MLS resolution for the entire OMPS vertical extent. Residual maps and distributions were made from the resulting differences, and correlations were made.
See the attached poster (presented at the 2017 American Meteorological Society Meeting by Steven Buckner) for more detail