MODAPS PCR 21-019

PCR Number 21-019
Date 2021-07-13
Initiator Sudipta Sarkar
Abstract PGE36 6.1.5, PGE37 6.1.5, PGE38 6.1.5

Added the FATAL ERROR output to log files and to exit the A2 processes when "Days_8_sum" from A1 files exceeds the standard number of days of 8 (5 or 6 for the last 8-day of the year). Similarly, output FATAL ERROR to log files and to exit the A3 processes when "Days_ann_sum" from A1 files exceeds 365 or 366.

Problem Statement On a number of occasions, the daily intermediate update files, needed, for the generation of the 8-day and annual products, would overshoot a given 8-day boundary and assimilate more days than 8 (8-day product) or 365/366 (annual product). This would lead to incorrect estimations of parameters in the 8-day products as well as in the annual product.
Description of Change In order to prevent such erroneous estimation of the science parameters, caused by the incorrect, out-of-sequence running of the daily update process, a check was added to the 8-day and the annual processes to throw a fatal error and exit, when the number of days, counted by the daily update process, was found to be more than 8 or 365/366 respectively.
Products Affected Gap-filled and regular C61 MxD17A1H* (daily-intermediate), MxD17A2H* (8-day), and MxD17A3H* (annual) products.
Software Affected PGE36 6.1.5; PGE37 6.1.5; PGE38 6.1.5
Processing String to Receive the Change Terra and Aqua Forward Processing. Terra and Aqua Reprocessing.
Downstream Product Effects None
Data Granules to be Used for Science Testing Science test was skipped, and unit tests were performed by LDOPE and STIG, as the changes were not pervasive and does not affect the science retrieval.
Justification The included change, to allow the 8-day and the annual process (PGE37/PGE38) to exit with fatal error, was needed to prevent overestimation of different science parameters, because of possible overshooting of the daily update process.
Effective Date for Implementation of Change PGE36/37/38 (V6.1.5) were inducted for C61 re-processing and forward processing, since 05/05/2020 (DOY 2020125).
Status Major algorithm development completed. Sadashiva Devadiga approved on 07/13/2021. Gang Ye approved on 07/14/2021.