This announcement is to inform our users of the Essential climate variables for assessment of climate variability from 1979 to present data.
Following an issue identified in ERA5T, which is used to generate the last three months of this dataset, the dataset was recently back-updated for September, October, November 2021. For details on the issue in ERA5T, please refer to our announcement on the user forum.
Update on 02/02/2022: Dataset now also back-updated for December 2021.
In practical terms, this means that if you have accessed Essential climate variables for assessment of climate variability from 1979 to present data for the period 1 September 2021 to 31 December 2021, we recommend that you download the data again.
As you may know, the Essential climate variables for assessment of climate variability from 1979 to present dataset is used as the basis to produce the C3S monthly climate bulletin.
The difference between the old and new datasets mainly affects Central Asia, is largest for soil moisture, but also affect, e.g., 2m temperature. For these variables, but other regions and for other variables and for aggregated statistics covered in the Climate Bulletin the difference is smaller than their respective typical error, and as such there is no further impact of the issue on the information or the numbers given in the Climate Bulletin.
All graphics and data-files shown in the bulletins for September to December have been updated and replaced for consistency with the underlying dataset.
Full details on this issue are available in the dataset documentation.
We apologize for the inconvenience this may cause.
If you have any questions, you may of course contact us.
ECMWF Support