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For a list of fields (parameters) in ERA-Interim and for downloading data see the ECMWF dataserver. Note that while ERA-Interim "runs" in near real time, data is published with a few moths months delay.
Note that we are aware of several quality issues with ERA-Interim data.
Please refer to the ERA-Interim daily retrieval efficiency documentation for best practices in retrieving ERA-Interim data.
Further documentation
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