MODAPS PCR 20-013
| PCR Number | 20-013 |
|---|---|
| Date | 2020-07-07 |
| Initiator | Sudipta Sarkar |
| Abstract | PGE175 v6.2.0 -- 1. Split MxD09CMG1 into two files, MxD09CMG1 and MxD09CMB1 2. Updated M{OY}D09CM{AG}1.fs; 3. Wrote new M{OY}D09CMB1.fs and M{OY}D09CMB1.061.mcf |
| Problem Statement | The current operational PGE175, being used in C61 re-processing, produces MxD09CMG1files that are massive in size, of around 5.5GB. This large file size was creating issues in archiving and accessing these files through LAADS LVFS. |
| Description of Change | PGE175 V6.2.0 alleviates the problem of extremely large MxD09CMG1 files by breaking the datasets of former MxD09CMG1 files, across MxD09CMG1 and a newly introduced ESDT of MxD09CMB1. This results in slightly smaller MxD09CMG1 files along with some additional datasets stored in the MxD09CMB1 files |
| Products Affected | MODIS C6 1KM Land Surface Reflectance CMG products |
| Software Affected | PGE175 6.2.0 |
| Processing String to Receive the Change | Terra and Aqua Forward Processing. Terra and Aqua Forward Reprocessing. |
| Downstream Product Effects | None |
| Data Granules to be Used for Science Testing | A science test was carried out in AS 1778 to confirm all changes and was reviewed and approved by LDOPE and the concerned science team. |
| Justification | The former operational PGE175 (V6.1.3), that was used in C61 re-processing, produced MxD09CMG1files that are massive in size, of around 5.5GB per day. Given the large size of these files the MxD09CMG1 would often give problem, while trying to access them through LVFS. This was brought to the attention of the science team, who decided to reduce the size of the main ESDT, MxD09CMG1, by splitting some of the component datasets of that ESDT into a new ESDT (MxD09CMB1). With this, the MxD09CMG1 file sizes have now come down to around 3.3 GB per day. |
| Effective Date for Implementation of Change | As soon as possible in the leading edge of C61 re-processing as of drafting this PCR (07/07/2020) |
| Status | Major algorithm development completed. Chris Justice approved on 07/28/2020. Sadashiva Devadiga approved on 07/23/2020. Gang Ye approved on 07/27/2020. |
