ADS Service disruption ENDED on 11 November 2022

UPDATE on 14 Nov 2022

We are delighted to inform our users that the DHS Move completed on 11 November 2022.

This means that access to all ADS data served from MARS tapes is fully restored.

UPDATE on 03 Nov 2022

The DHS-Move is expected to complete in the week commencing 7 Nov 2022.

While ADS data served from MARS tapes is gradually coming back online, users should not be attempting to retrieve such data until a further announcement is made, as results may be inconsistent.

The Support team can only provide limited support until access to the archive is fully restored.


As of 23 March, the Climate Data Store (CDS) and Atmosphere Data Store (ADS) are the first two user facing services operationally supported from our new Data Centre in Bologna. Following that successful migration, we would like to update you on the next steps in the transition to the Bologna Data Centre.

Following successful tests earlier this year (dry-runs of 5 April 2022, 26-28 April 2022 and 28 June-5 July), the ECMWF Data Handling System (DHS) Move, causing 28 days of reduced MARS (Meteorological Archival and Retrieval System) and ECFS (ECMWF's File Storage system (ECFS) service) service, is due to start on 8th September 2022

This degradation of the service may impact some of our Atmosphere Data Store (ADS) data users. This is because some of the data made available from the ADS are served from tapes in the ECMWF MARS system.

ADS data users should expect that the following ADS datasets served from MARS tapes and the following CDS datasets served from MARS tapes will not be accessible during the DHS moveUsers may still submit ADS data requests which will remain in the queue until data access is resumed.


> Click here to see the list of affected ADS datasets (MARS external, shown in Red) 


The information above is based on current expectations. For more details and to get notified about further updates and changes, please “Watch” our dedicated confluence space. We recommend our users to "Watch" this announcement page also.


Thank you for your patience during this significant migration to our new data centre which will enable exciting scientific developments and an overall better service to all ECMWF users.


ECMWF Support