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The ERA5 (reference C3S, 2017) global climate reanalysis assimilates observations of different meteorological quantities across the globe into a numerical model of atmospheric dynamics. It produces a large variety of output quantities including precipitation. ERA5 output is available in the CDS by C3S (https://cds.climate.copernicus.eu/cdsapp#!datasets/dataset/reanalysis-era5-single-levels?tab=overview) in hourly intervals and as monthly means at 0.25° spatial resolution, starting in 1979.
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Copernicus Climate Change Service (C3S) (2017): ERA5: Fifth generation of ECMWF atmospheric reanalyses of the global climate. Copernicus Climate Change Service Climate Data Store (CDS), 21/12/2018. https://cds.climate.copernicus.eu/cdsapp#!/home
Fennig, K. et al (2017): Fundamental Climate Data Record of Microwave Imager Radiances, Edition 3, Satellite Application Facility on Climate Monitoring, https://doi.org/10.5676/EUM_SAF_CM/FCDR_MWI/V003.
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