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It should be noted that some reanalysis systems aim at describing how reanalysis uncertainties depend on the weather situation, and for instance in ERA5 this has been done by using a so-called ensemble data assimilation system. (For a description of ensemble data assimilation, see for instance the report on the system developed by ECMWF, https://www.ecmwf.int/en/elibrary/1012574969-ensemble-data-assimilations-ecmwf .) Unlike ERA5, the CARRA dataset has not been produced with such a system, so we will provide overall "static", not "weather dependent", uncertainties.
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