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Mean rate/flux parameters in ERA5 (e.g. Table 4 for surface and single levels) provide similar information to accumulations (e.g. Table 3 for surface and single levels), except they are expressed as temporal averages, over the same processing periods, and so have units of "per second".
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Information on all ECMWF parameters (e.g. columns shortName and paramId) is available from the ECMWF parameter database.
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Parameters described as "invariants" below, are invariant in time.
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