MODAPS PCR 15-018
| PCR Number | 15-018 |
|---|---|
| Date | 2015-05-15 |
| Initiator | Sudipta Sarkar |
| Abstract | PGE25/PGE25Q v6.0.27. Changed the exit code when no valid input files are found, so that the PGE does not go into RunErr. PGE26 v6.0.2. Correct the angle SDSs attribute. Add MOD_PRL3CRS process for coarse product M*D13A3C. PGE27 v6.0.5. Change perl script to handle the new long term 5year CMG DB ancillary of gap filling. PGE28 v6.0.0. Updated PGE28 to port to C6. Added the new Metadata files. PGE35 v6.0.19. Changed the exit code when no valid input files are found, so that the PGE does not go into RunErr; Update PGE35.pl to run BROWSE process if input M*D13A2 is available. |
| Problem Statement | - QA flags from products at 500m and 1km resolution were not consistent. - Most of angle SDS attributes are incorrect and not consistent with the data values. - Unexpected data gap seen in the CMG products. - Snow and Cloud QA flags, and VI reliability datasets were incorrect. |
| Description of Change | - Generates 16-day composite VI using two 8-day composite reflectance product (MxD09A1) in the 16-day period. - This Surface Reflectance Input is based on the Minimum Blue compositing approach used to generate the 8 day LSR product. - Product format is consistent with the C5 version of the product generated using the L2G daily surface reflectance product, except for the change to the Relative Azimuth angle SDS (Range changed from [-360 - 360] to [-180 - 180]. - Update to the Long term Global CMG Average Vegetation Index Product database used to fill the gaps in the CMG product suite. |
| Products Affected | MxD13A1, MxD13Q1, MxD13A2, MxD13A3, MxD13C1, MxD13C2 |
| Software Affected | PGE25/25Q v6.0.27; PGE26 v6.0.2; PGE27 v6.0.5; PGE28 v6.0.0; PGE35 v6.0.19 |
| Processing String to Receive the Change | Terra Reprocessing and Aqua Reprocessing |
| Downstream Product Effects | None. |
| Data Granules to be Used for Science Testing | Process two 16-day periods of Aqua and Terra MODIS using the C6 data and new CMG database file provided by the science team. Adjust production rules for the 16-day CMG Algorithm/Product to change the gap-filling database used for processing.2010-059 |
| Justification | Though there isn't any anomaly and inaccuracy in the science data (NDVI and EVI), incorrect QA flags, SDS attributes, and reliability datasets are inconsistent, making the product post processing with QA/Ranking inaccurate. Reprocessing of the entire suite of VI products is recommended with all of the implemented changes since introducing these changes midway in the C6 reprocessing could introduce temporal inconsistency in the dataset from the collection reprocessing and could introduce undesired trending in the long time series of the products. |
| Effective Date for Implementation of Change | Completed. |
| Status | Major algorithm development completed. Sadashiva Devadiga approved on 05/15/2015. Michael King approved on 05/26/2015. |
