Pre-operational Evaluation of JPSS-1 Science Algorithms and Data Products

The Joint Polar Satellite System (JPSS) program anticipates the launch of the JPSS-1 (J1) satellite in 2017.  The J1 and follow-on satellites will host an array of instruments including the Visible Infrared Imaging Radiometer Suite (VIIRS), the Cross-track Infrared Sounder (CrIS), the Advanced Technology Microwave Sounder (ATMS), and the Ozone Mapping and Profiler Suite (OMPS).  These instruments are similar to the instruments currently operating on the Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite.  The J1 satellite will produce baseline products and new additional products as a direct result of the instrument upgrades (e.g. CrIS & OMPS) and science improvements.  In preparation for the J1 launch, the JPSS Program at the Center for Satellite Applications and Research (JSTAR) has developed plans for J1 science algorithm development, calibration and validation (cal/val), schedules and deliverables, and infrastructure for routing J1 science product algorithms into operations.  The JSTAR team has coordinated with the Test Data Working Group (TDWG) and formulated desired test data sets for VIIRS, OMPS, CrIS and ATMS instruments to facilitate J1 algorithm development and testing. The data sets included J1 proxy data generated from the Suomi-NPP and the J1 Thermal Vacuum Chamber (TVAC) instrument measurements.  All of the Sensor and Environmental Data Record (SDR/EDR) teams have used these data sets for pre-launch characterization of the J1 science algorithms and associated SDR and proxy-EDR products.  The JSTAR team has also conducted and coordinated VIIRS J1 instrument waiver telecons. A total of 13 J1-VIIRS instrument waivers and associated impacts on the VIIRS SDR and EDR products have been evaluated through deliberations with the SDR/EDR teams, VIIRS instrument team members, user agencies, and stake holders.  Algorithm upgrades to mitigate certain instrument waivers and test data sets needed for evaluation have been identified and realized through coordination with the TDWG. This paper provides an overview of these efforts and the accomplishments. As an example, the use of OMPS43 test data set to develop and test the OMPS J1 SDR algorithm and the use of VIIRS-FPX test data to develop, test, and evaluate the VIIRS SDR algorithm to work for aggregation zones 21 and 21/26 are discussed. In essence, the test data sets have helped to refine and deliver the J1 algorithm code accounting for instrument upgrades and mitigations to certain instrument waivers.

The JSTAR team also coordinated science product verification support as part of the Block 2.0 ground system transition and operational readiness review (ORR).  The objective is to ensure that science products are not impacted through Block 1.2/2.0 ground project transition.   As part of this support, live S-NPP science data products as well as J1 proxy data products generated from Block 1.2 and Block 2.0 systems have been verified for science product integrity during Operations-Based Site Acceptance Test (OBSAT) and LG2 tests (Level 3, Ground Project/Segment Acceptance Test). Although the SDR/EDR teams reported minor glitches with data push protocols to STAR and issues related to minor radiance and geo-location differences due to look-up-table changes, science evaluation of SDR/EDR products displayed close agreement indicating that science results are not impacted on Block 1.2/2.0 Suomi-NPP/J1 product transition. Further post-LG2 follow-up plans and coordination are planned with the JPSS Algorithm Management Program, TDWG, and the Interface Data Processing Segment teams to receive J1 spacecraft TVAC data sets through the ground system to ensure first order format checking and analysis. This paper presents these evaluations as part of pre-operational demonstration for the J1 satellite.  Future plans of post-launch validation are also discussed in anticipation for a successful J1 launch.