# Release of an additional ERA5 back extension for 1940-1958 **URL:** \ **Category:** C3S - Announcements\ **Tags:** c3s, era5\ **Created:** [3 March 2023 10:05 UTC](https://forum.ecmwf.int/t/release-of-an-additional-era5-back-extension-for-1940-1958/834 "2023-03-03T10:05:28Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Anabelle](https://forum.ecmwf.int/user_avatar/forum.ecmwf.int/anabelle/32/360_2.png) [@Anabelle](https://forum.ecmwf.int/u/Anabelle)\ **Post date:** [3 March 2023 10:05 UTC](https://forum.ecmwf.int/t/release-of-an-additional-era5-back-extension-for-1940-1958/834/1 "2023-03-03T10:05:28Z")
We are delighted to inform our users that the Copernicus Climate Change Service (C3S) at ECMWF has released today, Tuesday 7th March 2023, the final version of the ERA5 back extension data covering the period 1940-1958 on the Climate Data Store (CDS) - see [The family of ERA5 datasets](https://confluence.ecmwf.int/x/icrLCg "https://confluence.ecmwf.int/x/icrLCg"). ERA5 1940-present continues to be extended forward in time, with daily updates being made available 5 days behind real time. To download the ERA5 data including back extension period to 1940, please follow our guidelines on [How to download ERA5](https://confluence.ecmwf.int/display/CKB/How+to+download+ERA5) Our extensive [ERA5 Documentation](https://confluence.ecmwf.int/display/CKB/ERA5%3A+data+documentation) has also been updated. If you have any questions or feedback about the above, please [contact us](https://climate.copernicus.eu/help-and-support). Regards, ECMWF Support