MODAPS PCR 22-008
| PCR Number | 22-008 |
|---|---|
| Date | 2022-07-11 |
| Initiator | Sudipta Sarkar on behalf of P.I. Alexei Lyapustin |
| Abstract | PGE113 6.1.20 -- Only major changes have been shown here for brevity: 1. Change the "dayback" period to 180 days |
| Problem Statement | The PGE113 was not being able to resume the processing of the polar tiles once the inputs for those picked up in the following year spring or summer. It was not looking further back to pick up the prior year coefficient files. It was also not checking on the status of the upstream PGE165 correctly and was going to RunOk even when the upstream PGE165 showed NoRun status. |
| Description of Change | The PGE113 loader module (LM) was changed to look back for a longer period, to be able to pick up the last set of correctly produced coefficient files, across seasonal and large instrument outage periods. The LM was also updated to look for correct minimal set of inputs from upstream PGE165. |
| Products Affected | Daily C61 L3 Tiled MAIAC products, MCD19A1, MCD19A2, and MCD19A3D |
| Software Affected | PGE113 6.1.20 |
| Processing String to Receive the Change | Terra and Aqua Forward Processing. Terra and Aqua Reprocessing. NRT |
| Downstream Product Effects | None. |
| Data Granules to be Used for Science Testing | The PGE113 LM change was successfully tested through MODIS INT instance tests and was also verified through random spot checks, across different tiles, once the change was provisionally put in to resume the processing. A formal science test could not be carried out due to the difficulties associated with syncing accurately all the global set of intermediate files to a separate test instance. |
| Justification | The C61 reprocessing of MAIAC was leaving sporadic gaps across different high latitude tiles, because of inability to accurately assess the status of upstream gridded L1B process and not being able to look back for a sufficient period to fetch the last set of correct coefficient files. |
| Effective Date for Implementation of Change | The changes to the PGE113 LM was put in to resume the MAIAC reprocessing, starting PGE_StartTime of 2000-12-16 and from 06/25/2022 onwards. |
| Status | Major algorithm development completed. Sadashiva Devadiga approved 07/015/2022. Sudipta Sarkar approved 07/15/2022. |
