10m zonal and meridonal wind over North and South Pole (90N/S) differ between CDS and CEDA

Dear All:

Recently while checking some ERA5 hourly data that are available from Climate Data Store and CEDA (UK), it appears that hourly 10m U and Vs over 90S and 90N for older data (shown to be the case for 1988) do not agree.

Has there been updates/reruns that could have caused such discrepancies?

As for now, I am taking the CDS data to be the “correct” one.

There may be other variables show such differences, but I have not checked.

Best Regards,

Steven Chan