HESS Hydrology and Earth System Sciences HESS Hydrol. Earth Syst. Sci. 1607-7938 Copernicus Publications Göttingen, Germany 10.5194/hess-19-389-2015 ERA-Interim/Land: a global land surface reanalysis data set Balsamo G. https://orcid.org/0000-0002-1745-3634 1 Albergel C. https://orcid.org/0000-0003-1095-2702 1 Beljaars A. 1 Boussetta S. 1 Brun E. 2 Cloke H. https://orcid.org/0000-0002-1472-868X 3 Dee D. 1 Dutra E. https://orcid.org/0000-0002-0643-2643 1 Muñoz-Sabater J. https://orcid.org/0000-0002-5997-290X 1 Pappenberger F. https://orcid.org/0000-0003-1766-2898 1 de Rosnay P. https://orcid.org/0000-0002-7374-3820 1 Stockdale T. 1 Vitart F. 1 European Centre for Medium-Range Weather Forecasts (ECMWF), Reading, UK Météo-France, Toulouse, France University of Reading, Reading, UK 21 01 2015 19 1 389 407 Copyright: © 2015 G. Balsamo et al. 2015 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://hess.copernicus.org/articles/19/389/2015/hess-19-389-2015.html The full text article is available as a PDF file from https://hess.copernicus.org/articles/19/389/2015/hess-19-389-2015.pdf

ERA-Interim/Land is a global land surface reanalysis data set covering the period 1979–2010. It describes the evolution of soil moisture, soil temperature and snowpack. ERA-Interim/Land is the result of a single 32-year simulation with the latest ECMWF (European Centre for Medium-Range Weather Forecasts) land surface model driven by meteorological forcing from the ERA-Interim atmospheric reanalysis and precipitation adjustments based on monthly GPCP v2.1 (Global Precipitation Climatology Project). The horizontal resolution is about 80 km and the time frequency is 3-hourly. ERA-Interim/Land includes a number of parameterization improvements in the land surface scheme with respect to the original ERA-Interim data set, which makes it more suitable for climate studies involving land water resources. The quality of ERA-Interim/Land is assessed by comparing with ground-based and remote sensing observations. In particular, estimates of soil moisture, snow depth, surface albedo, turbulent latent and sensible fluxes, and river discharges are verified against a large number of site measurements. ERA-Interim/Land provides a global integrated and coherent estimate of soil moisture and snow water equivalent, which can also be used for the initialization of numerical weather prediction and climate models.

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