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ERA-20C assimilates observations of surface pressure and surface marine winds only. It is an outcome of the ERA-CLIM project.
The ERA-20C analysed surface parameters that are only available 6-hourly are those that are produced by the land-surface analysis scheme. Separate from the 4D-Var assimilation, the land-surface analysis scheme runs every 6 hours and only produces one temporal estimate at the centre of each 6-hour window. These 6-hourly parameters are:
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Currently there are no known issues with ERA-20C.
Data access
Data is archived at ECMWF and available for download from ECMWF data services.
References
Poli, P., H. Hersbach, D.P. Dee, P. Berrisford, A.J. Simmons, F. Vitart, P. Laloyaux, D.G. Tan, C. Peubey, J. Thépaut, Y. Trémolet, E.V. Hólm, M. Bonavita, L. Isaksen, and M. Fisher. ERA-20C: An Atmospheric Reanalysis of the Twentieth Century, Journal of Climate, 2016, 29:11, 4083-4097, Doi: 10.1175/JCLI-D-15-0556.1
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