MODAPS PCR VNP 25-009
| PCR Number | VNP 25-009 |
|---|---|
| Date | 2025-08-06 |
| Initiator | Carol Davidson |
| Abstract | PGE628 2.0.3 Revised PGE628 code to work with new x-cal factors and scale factor reference files for JPSS2, SNPP and JPSS1. This includes adding logic to the PGE to accept JPSS2 input/output ESDTs and SatelliteInstrument name. This update also includes new scale factor reference files, one for each VIIRS mission, which were provided by Eric Vermote. The new reference files are named: JPSS1_Scale_Factors_C2_v2.txt, JPSS2_Scale_Factors_C2_v2.txt and SNPP_Scale_Factors_C2_v2.txt. Please see attached VJ2-Crosscal.pptx for more information on this revision. |
| Problem Statement | Created a new version of VIIRS cross-calibrated L1B PGE628 using revisions provided by Eric Vermote. The changes added JPSS2 support, which included revisions to use a set of x-cal factors that incorporates the cross-calibration of JPSS2 with relationship to SNPP and JPSS1. This revision alaso changes the x-cal factors of SNPP and JPSS1 to be change from time-dependent to time-independent ones, which will be used for SNPP and JPSS1 C2 leading edge processing. New version prepared is PGE628 2.0.3. |
| Description of Change | Revised PGE628 code to work with new x-cal factors and scale factor reference files for JPSS2, SNPP and JPSS1. This includes adding logic to the PGE to accept JPSS2 input/output ESDTs and SatelliteInstrument name. This update also includes new scale factor reference files, one for each VIIRS mission, which were provided by Eric Vermote. The new reference files are named: JPSS1_Scale_Factors_C2_v2.txt, JPSS2_Scale_Factors_C2_v2.txt and SNPP_Scale_Factors_C2_v2.txt. Please see attached VJ2-Crosscal.pptx for more information on this revision. |
| Products Affected | VNP02CCMOD,VNP02CCIMG,VJ102CCMOD,VJ102CCIMG,VNP02CCMOD_NRT,VNP02CCIMG_NRT,VJ102CCMOD_NRT,VJ102CCIMG_NRT, VJ202CCMOD, VJ202CCIMG |
| Software Affected | PGE628 2.0.3 |
| Processing String to Receive the Change | S-NPP Forward Processing. J1 Forward Processing. J2 Forward Processing. J2 Reprocessing. NRT |
| Downstream Product Effects | All VIIRS land products |
| Data Granules to be Used for Science Testing | A science test was conducted of PGE628 2.0.3-0 on ops4 AS4078 using SNPP, JPSS1 and JPSS2 data and processed through L2 LSR and LSR CMG to support evaluation of CC L1B. The outputs were reviewed by Eric Vermote and LDOPE and all agreed that the new PGE628 could be used in leading edge processing for SNPP and JPSS1, and for C2 reprocessing/leading edge. |
| Justification | Initial version for use in JPSS2 C2 reprocessing chain, which will help align the data used to that in use in SNPP and JPSS1 with the implementation of the x-cal values. Please see attached powerpoint for summary of improvements CC L1B makes for JPSS2 L1B data. |
| Effective Date for Implementation of Change | PGE628 2.0.3 was put into use for C2 NPP and JPSS1 leading edge, both standard and NRT processing, starting 8/7/25. It was also put into the extended JPSS2 test archive, AS4014, start use 8/7/25, to allow for testing and review by both LDOPE and science team. LDOPE has reviewed data produced since the new version went in and confirmed the data is good. This PCR is to document the update and when it went into use. |
| Status | Sadashiva Devadiga approved 09/03/2025. Carol Davidson implemented 08/07/2025. |
