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As a result, for the months July, August, September and October 2024, the final ERA5 product is (and will be) different from ERA5T (the preliminary version of ERA5 made available about 5 days after real time). The differences are mostly limited to the Alps and mainly to surface parameters (in particular snow depth and 2m temperature and 2m dewpoint temperature). However, all the resulting reanalysis fields do differ slightly over the whole globe but these differences should be within their range of uncertainty (which is estimated by the ensemble spread and which can be large for some parameters). On the Climate Data Store (CDS), the initial (ERA5T) fields have been/will be overwritten, i.e., for these months, access to the original CDS ERA5T product will not be possible after it has been overwritten.
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