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There have been a significant number of changes to the model namelists and initial data format compared to OpenIFS 43r3. It is recommended that users do not attempt to use OpenIFS 43r3 namelists with OpenIFS 48r1 but should obtain new obtain new experiment data and matching namelists suitable for model cycle 48r1.Further due to the implementation of the multi-layer snow scheme and other updates, the format of the initial experiment data used for OpenIFS 48r1 is different from that used in OpenIFS 43r3.
The recommended way to obtain initial experiment data for forecast experiments with OpenIFS is to use the OpenIFS Data Hub. For any data requests that are currently not served by the Data Hub please contact OpenIFS support by emailing openifs-support@ecmwf.int.
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