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Model levels: 1/to/137, which are described at https://www.ecmwf.int/en/forecasts/documentation-and-support/137-model-levels L137 model level definitions and ERA5: compute pressure and geopotential on model levels, geopotential height and geometric height. The model levels are hybrid pressure/sigma. For more information, see the documentation of the underlying model, ECMWF's IFS, CY41R2, Part III. Dynamics and numerical procedures, Chapter 2 Basic equations and discretisation.
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For complete details, please refer to How to acknowledge and cite a Climate Data Store (CDS) catalogue entry and the data published as part of it.
For ERA5 data in MARS,
If you have downloaded ERA5 data in MARS, using either the CDS API ('reanalysis-era5-complete' or 'reanalysis-era5.1-complete' or ') or via authorised direct access to MARS, please contact us.reanalysis-era5-complete-preliminary-back-extension'
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