File-level metadata anomaly in the GHRSST MODIS Terra L2P Sea Surface Temperature dataset
It has come to our attention that a large number of netCDF granules in the most recent version 2019.0 Terra L2P SST dataset (https://doi.org/10.5067/GHMDT-2PJ19) have an incorrect value in the file-level global metadata for the version. For the erroneous granules, the global metadata attribute “product_version” has a value of “2014.0” instead of “2019.0”.
We have investigated the source of this error and discovered an improper setting in the runtime software that caused granules to be stamped with the wrong version and other anomalies. Furthermore, we have tested several affected files in our archive and compared them to the version 2019.0 Level 2 MODIS Terra SST source files from the NASA Ocean Biology Processing Group. They compare exactly at the pixel level for the SST and quality flag variables where differences would be apparent between v2014.0 and v2019.0 data. The conclusion is that the current GHRSST Terra L2P SST time series data is v2019.0 even though most of the granules are identified as v2014.0.
The GHRSST Terra SST L2P time series will be reprocessed to correct the affected granules for years 2003 to 2019, with an estimated completion date by October 2021.