Hydrology and Earth System Sciences Discussions www.hydrol-earth-syst-sci-discuss.net 1812-2108 1812-2116 6 2 2009 10.5194/hessd-6-2733-2009 http://www.hydrol-earth-syst-sci-discuss.net/6/2733/2009/ http://www.hydrol-earth-syst-sci-discuss.net/6/2733/2009/hessd-6-2733-2009.html http://www.hydrol-earth-syst-sci-discuss.net/6/2733/2009/hessd-6-2733-2009.pdf 2733 2750 2009-03-27 Assessment of soil moisture fields from imperfect climate models with uncertain satellite observations G. Schumann guy.schumann@bristol.ac.uk D. J. Lunt P. J. Valdes R. A. M. de Jeu K. Scipal P. D. Bates School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK Geological Sciences Division, British Antarctic Survey, Cambridge, CB3 0ET, UK Department of Hydrology and Geo-Environmental Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands Institute of Photogrammetry and Remote Sensing, Vienna University of Technology, 1040, Vienna, Austria We demonstrate that global satellite products can be used to evaluate climate model soil moisture predictions but conclusions should be drawn with care. The quality of a limited area climate model (LAM) was compared to a general circulation model (GCM) using soil moisture data from two different Earth observing satellites within a model validation scheme that copes with the presence of uncertain data. Results showed that in the face of imperfect models and data, it is difficult to investigate the quality of current land surface schemes in simulating hydrology accurately. 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