Introduction 


A new Climate Data Store (CDS) and a new Atmosphere Data Store (ADS) powered by a new state-of-the-art infrastructure, referred to as the Common Data Store (CDS) Engine, are soon to be launched. 

All layers of the CDS an ADS infrastructure are being modernised: the front-end web interface, the back-end software engine and the underlying cloud infrastructure hosting the service and core data repositories. 


What does this mean in practice to current CDS and ADS users?

User account:

ECMWF Single Sign-On (SSO) has been extended to all its platforms including the new CDS and ADS. SSO allows users to have access to multiple applications by signing in with only one account. It also has other important features in regard to simple management, security, ease of use, and seamlessness.

All users of the new CDS and new ADS will need an ECMWF account. If you do not yet have an ECMWF account, you may already register with ECMWF

As a consequence of the single sign-on implementation, your current CDS or ADS login credentials will not work on the new CDS or ADS infrastructure, regardless of whether you are currently using the CDS or ADS interactively (e.g. over the web interface) or programmatically (using the API service). A new UserID (ECMWF) and API key will be needed.

Your ECMWF account will only allow you to login to the new CDS/ADS, not onto the current CDS/ADS.

You cannot use your ECMWF account to log in onto the current CDS or current ADS. SSO does not apply to current CDS nor current ADS.



CDS/ADS Catalogue - data download over web interface: 

  • Before downloading any data from the new CDS or ADS infrastructure, users will have to accept datasets terms and conditions on the new system. Users' profiles including licensing information are not being transferred. In practical terms, this means for example that if you are downloading ERA5 data (web or API) from the current CDS, you will need to login to the new CDS and accept the terms and conditions for ERA5 (i.e. Licence to use Copernicus Products).

Additional information to come soon.


API Service - programmatic way of downloading data: 

  • A new version of the cdsapi package has been released. API users need to upgrade their CDS API (i.e pip install --upgrade cdsapi). Note that the new version of the cdsapi package works on both the current and new CDS. 
  • You will need to update your .cdsapirc file with your new credentials (key, URL) to be able to download data from the new CDS.
  • CDS API syntax is changed and some keys or parameter names may have also changed. To avoid requests failing, please use the "Show API request code" tool on the dataset Download Form on the new CDS to check you are using the correct syntax for your API request. 


CDS Toolbox, Viewers and Applications:

The CDS Toolbox will be discontinued and is not migrated to the new CDS infrastructure. Support will continue to be provided to CDS Toolbox users until the CDS Toolbox is shutdown in September 2024. ECMWF Support will however not be able to help with supporting users migrating their CDS Toolbox workflows on to another programming language/software.

As a consequence of the CDS Toolbox being discontinued, the Viewer tool for the following datasets in the CDS will also be discontinued. 

New tool packages will be made available (post new CDS launch) to provide software tools for weather and climate workflows that simplify data access, analysis, visualisation and much more. 


Feedback and reporting bugs/issues:

Please send your feedback and/or report any issue/bug you may have encountered while using the new CDS and ADS infrastructure by raising an enquiry ticket through our dedicated  Support Portal (ECMWF login required) - make sure you select "Yes" to the question Is this request related to CDS-beta/ADS-beta/CEMS-EW-beta? on the Support Portal request form - this will help the Support team with triaging enquiries more efficiently.


Good to know

  • The current CDS and ADS will be completely shutdown in September 2024. Should users still have API scripts pointing to the retired CDS and ADS systems, these will systematically break and no support will be provided. 


This document has been produced in the context of the Copernicus Atmosphere Monitoring Service (CAMS) and Copernicus Climate Change Service (C3S).

The activities leading to these results have been contracted by the European Centre for Medium-Range Weather Forecasts, operator of CAMS and C3S on behalf of the European Union (Delegation Agreement signed on 11/11/2014 and Contribution Agreement signed on 22/07/2021). All information in this document is provided "as is" and no guarantee or warranty is given that the information is fit for any particular purpose.

 The users thereof use the information at their sole risk and liability. For the avoidance of all doubt , the European Commission and the European Centre for Medium - Range Weather Forecasts have no liability in respect of this document, which is merely representing the author's view.


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