Assessment of NUCAPS S-NPP CrIS/ATMS Sounding Products Using Reference and Conventional Radiosondes

The Suomi-NPP was launched in October 2011 to serve as the risk-reduction mission between the previous NOAA polar series and the future JPSS satellites. The sounding instruments onboard the Suomi-NPP) include  the Cross-track Infrared Sounder (CrIS) and the Advanced Technology Microwave Sounder (ATMS), comprising a synergistic system that is designed to retrieve  atmospheric vertical temperature and water vapor profiles with the vertical resolution similar to  the EUMETSAT MetOp-A and -B Infrared Atmospheric Sounding Interferometer (IASI) and the NASA-EOS Aqua Atmospheric Infrared Sounder (AIRS).

In this work, the NOAA Unique Combined Atmospheric Processing System (NUCAPS) CrIS/ATMS sounding products from Suomi-NPP are assessed using reference and conventional radiosonde observations. Reference radiosondes are those processed using software developed in coordination with the GCOS Reference Upper Air Network (GRUAN).  These includes subsets of  JPSS-funded satellite synchronized radiosondes launched at  U.S. DOE Atmospheric Radiation Measurements (ARM) sites and in special field campaigns such as NOAA Aerosols and Ocean  Expeditions (AEROSE), CalWater 2015 ARM Cloud Aerosol Precipitation Experiment (ACAPEX) over the north Pacific Ocean and the 2016 El Nino Rapid Response Experiment (ENRR). Conventional RAOBs on the other hand are typically launched twice a day at about 850 sites globally and are used for numerical weather prediction (NWP) assimilation and forecasting. Conventional and Reference RAOBs are complementary in support of the JPSS sounding EDR calibration/validation (cal/val), and respectively serve as anchors for compiling multiple satellite product collocations  in the NOAA  Products Validation System (NPROVS) and its expansion NPROVS+. Validation uncertainties arising from temporal and spatial mismatch between RAOB launch and satellite overpass, potential RAOB accuracy issues, and inconsistencies in radiosonde versus satellite product vertical resolution inconsistencies are included in discussions.  Inter-satellite product comparison versus the radiosondes and new procedures to integrate the GRUAN reference radiosonde uncertainty in cal/val are also presented.