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For dates before this system check was introduced into ERA5 (i.e. for the period January 1979 to 18 February 2020), the two tables below give details when the analysed 10m wind components (the 10 metre U wind component and 10 metre V wind component) exceed 50 ms-1. The CDS API script below can be used to retrieve the "4v" 10m wind components, which don't usually suffer from this large wind problem.

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titleCDS API script to retrieve the "4v" 10m winds

The CDS API script below can be used to retrieve the "4v" 10m wind components from the ECMWF data archive, MARS. For more information on how to use this script, see How to download ERA5.

Code Block
#!/usr/bin/env python
import cdsapi
 
c = cdsapi.Client()
c.retrieve('reanalysis-era5-complete', {     # do not change this!
    'stream'  : 'oper',
    'type'    : '4v',
    'levtype' : 'sfc',
    'param'   : '165.128/166.128',
    'date'    : '1986-07-23',
    'time'    : '21',
    'step'    : '12',
    'grid'    : '0.25/0.25', # Latitude/longitude grid: east-west (longitude) and north-south resolution (latitude). Default: reduced Gaussian grid
    'format'  : 'grib', # Default: grib, supported netcdf.
}, 'outfile.grib')

For the temporal specification, the CDS uses the validity date and time, whereas MARS uses date, time and step. The 4v trajectories begin from 9 and 21 UTC and you should use the step is hourly steps from 1 to 12 hours. In the script above, the validity date/time is would be given by adding the step, 12 hours, to the time, 21 UTC. This yields a validity date/time of 1986-07-24 , at 9 UTC, which is the 12th event in the first table below, for the 10m U.

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