As part of our expansion of our product offerings based on ARCO (Analysis Ready Cloud Optimized) capabilities, we are pleased to announce direct tokenized access to ERA5 and ERA5-Land data cubes.
In our CDS catalogue of datasets, ERA5 hourly data on single levels and ERA5-Land hourly data entries now include a new “Analysis ready data” tab (alongside the existing Overview, Download, Documentation and Quality tabs) with instructions including code snippet showing how to open a Zarr store using xarray:
- ERA5 hourly data on single levels from 1940 to present - Analysis ready data
- ERA5-Land hourly data from 1950 to present - Analysis ready data
Please note that only a subset of the ERA5/ERA5-Land single-levels dataset is presently made available in analysis-ready, cloud-optimised (ARCO) Zarr stores. Requirements for additional parameters may be considered. Please raise your request with ECMWF Support here.
The ARCO/zarr data is a repackaged version of the original ERA5/ERA5-land data. Homogenisation conventions have been applied to the ERA5 source GRIB data to ensure consistency, usability, and alignment across chosen variables and time steps. The processed data were then written to an ARCO Zarr archive, enabling efficient cloud-optimised access and scalable data retrieval.
The ARCO/zarr data is provided in two chunking formats, geo-chunked and time-chunked to retrieve long time periods for a limited area (geo-chunked) or short time periods for large areas (time-chunked). The geo-chunked data is what powers the fast access to long time-series data via the download forms of the ERA5 hourly time-series data on single levels and the ERA5 Land hourly time-series data catalogue entries. A new Analysis ready data tab has also been added on the ERA5 and ERA5-Land time-series catalogue entries to show how to programmatically download the same data (as presented on the download tab of the ERA5/ERA5-Land time-series).
For general information about the ARCO data service and recommended usage please refer to the Analysis Ready Cloud Optimised Data Documentation.
Finally, please be aware that the Analysis-ready cloud-optimised (ARCO) data access is a beta service
Data Store Service administrators reserve the right to take the necessary actions at any moment, including closing access, to maintain the overall performance of the Data Store Service.
For any enquiries regarding this, please contact us.
ECMWF Support on behalf of the DSS team