Description of upgrade

The porting of CAMS IFS cycle 47r3 from the Cray to the Atos HPC, the new ECMWF High-Performance Computing facility in Bologna, is a purely technical change. The test system currently running on the Atos HPC is using the same IFS cycle, 47r3, as the current operational system. 

The test data is expected to be scientifically equivalent to the operational products; small numerical differences may however be expected due to the system running on a different supercomputer. Test data should not be used for any operational purposes. 

The switch-over of the operational forecast production from the current Cray HPC to the new Atos HPC is currently scheduled for 18 October 2022. The 12UTC analysis and forecast model cycle will be the first cycle available on that day.

Further information and advice regarding the upgrade can be obtained through the ECMWF Support Portal.

Technical content

Users should not see any technical differences between the Atos CAMS data and products and current operational ones produced on our Cray systems in Reading. Users can continue using their existing software packages to decode the Atos IFS Cycle 47r3 CAMS data.  See Implementation of IFS cycle 47r3 for more details on last CAMS update and SW requirements.

Atos IFS Cycle 47r3 test data and products

Please see Accessing CAMS 47r3 test data.