MODAPS PCR VNP 25-008
| PCR Number | VNP 25-008 |
|---|---|
| Date | 2025-06-02 |
| Initiator | Carol Davidson |
| Abstract | PGE665 2.0.0, PGE613 2.0.1, 2.0.5, 2.0.7 Official C2 version of VIIRS MAIAC, VNP19A1, VNP19A2, VJ119A1, VJ119A2, and VCD19A3. The VIIRS code is based on the MODIS MAIAC but with specific VIIRS adjustments, including use of new rotated SIN tiles. Initial set of dump input files come from test archive AS4041 per direction from MAIAC science team. Processing started with PGE613 v2.0.1, then starting day 5/18/12 we went to PGE613 2.0.5, with a change from SCF to improve AOD retrieval at some rare cases. Then starting 7/1/19, we went to PGE613 2.0.7 which has SCF change AOD retrieval ONLY if src is biased high by clouds. PGE613 2.0.7 also has some changes to the bounding coordinate values for v00 and v17 tiles. PGE613 v2.0.7 is to be used for processing the v00, v17, some v01 and some v16 tiles for the full mission, starting with NPP and going through to the leading edge. |
| Problem Statement | Initial C2 version of VIIRS MAIAC, which consists of PGE665/Gridded Pre-MAIAC, and PGE613/MAIAC. Processing started on ops3, AS5200, start data day 01/19/12 with NPP data and then both NPP and JPSS1 data to be used from data day 1/5/18 onward. Processing was paused when we had completed data year 2012 so LDOPE could do a review. Once reviewed, processing resumed. Outputs will consist of NPP, JPSS1, and NPP+JPSS1 combined output products. |
| Description of Change | Official C2 version of VIIRS MAIAC, VNP19A1, VNP19A2, VJ119A1, VJ119A2, and VCD19A3. The VIIRS code is based on the MODIS MAIAC but with specific VIIRS adjustments, including use of new rotated SIN tiles. Initial set of dump input files come from test archive AS4041 per direction from MAIAC science team. Processing started with PGE613 v2.0.1, then starting day 5/18/12 we went to PGE613 2.0.5, with a change from SCF to improve AOD retrieval at some rare cases. Then starting 7/1/19, we went to PGE613 2.0.7 which has SCF change AOD retrieval ONLY if src is biased high by clouds. PGE613 2.0.7 also has some changes to the bounding coordinate values for v00 and v17 tiles. PGE613 v2.0.7 is to be used for processing the v00, v17, some v01 and some v16 tiles for the full mission, starting with NPP and going through to the leading edge. |
| Products Affected | VNP19A1, VNP19A2, VJ119A1, VJ119A2, and VCD19A3 |
| Software Affected | PGE665 2.0.0, PGE613 2.0.1, 2.0.5, 2.0.7 |
| Processing String to Receive the Change | S-NPP Forward Processing. S-NPP Reprocessing. J1 Forward Processing. J1 Reprocessing. |
| Downstream Product Effects | All VIIRS land products |
| Data Granules to be Used for Science Testing | Prior to starting processing with PGE613 2.0.1, a science test was conducted using PGE665 and PGE613 in AS4041 and results reviewed by LDOPE and the MAIAC science team. For move of PGE613 to v2.0.5, no science test was done, but for PGE613 v2.0.7, numerous tests were done including several checks with LP DAAC to confirm the polar tile products would ingest correctly to their system. |
| Justification | For continuity of the MAIAC product from MODIS to VIIRS |
| Effective Date for Implementation of Change | PGE665 2.0.0 and PGE613 2.0.1 were put into use in C2 reprocessing on 2/4/2025 with data start of 1/19/12. PGE613 2.0.5 was installed on 2/24/25 and started use with 5/18/2012. PGE613 2.0.7 was installed on 5/29/25 and data start use was 7/1/2019. Polar Tile processing will use PGE613 v2.0.7 starting from 1/19/12. |
| Status | Sadashiva Devadiga approved 06/03/2025. Sudipta Sarkar implemented 06/02/2025. |
