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With the aim to cover the large diurnal cycle of OLR, the daily CDR used all available satellite overpasses and exploits geostationary observations to model the diurnal variation between the HIRS observations. There are two different versions of the dataset due to a latency (about 6 to 9 months) in the release of the Gridded Satellite data (GridSat) CDR, used for the calibration of the final product. During the latency period a preliminary version is generated using the Geostationary Surface and Insolation Products (GSIP) instead of the GridSat. This preliminary dataset is considered as an Interim Climate Data Record (ICDR) and the final dataset is considered as the Thematic Climate Data Record (TCDR). For the preliminary dataset the word preliminary is included in the name of each product as presented below:
Final Version: olr-daily_v01r02_20200101_20201231.nc
Preliminary Version: olr-daily_v01r02-preliminary_20210101_20211231.nc
The preliminary data will be reprocessed as “final” once all the GridSat data are available.
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