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In January 2019, a problem was identified regarding the following data in the climate data store (CDS):
| CDS Dataset | ERA5 hourly data on pressure levels from 1979 to present |
|---|---|
| Parameters affected | U-component of wind, V-component of wind |
| Level | All pressure levels |
| Time periods affected | All ERA5 pressure-level winds of product type Reanalysis and Ensemble members |
Only exactly at the poles (i.e., where latitude is 90N or 90S), the values of the U and V components of the wind are far too low. Values are close to zero, rather than several m/s. At all other locations the winds are unaffected.
This problem is caused by the way these winds were determined from Vorticity and Divergence in spherical harmonics representation (the native model representation) when interpolated to a regular grid in the Climate Data Store.
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