HESS Hydrology and Earth System Sciences HESS Hydrol. Earth Syst. Sci. 1607-7938 Copernicus Publications Göttingen, Germany 10.5194/hess-13-259-2009 Matching ERS scatterometer based soil moisture patterns with simulations of a conceptual dual layer hydrologic model over Austria Parajka J. 1 3 Naeimi V. 2 Blöschl G. 1 Komma J. 1 Institute for Hydraulic and Water Resources Engineering, Vienna University of Technology, Austria Institute of Photogrammetry and Remote Sensing, Vienna University of Technology, Austria Institute of Hydrology, Slovak Academy of Sciences, Bratislava, Slovakia 23 02 2009 13 2 259 271 Copyright: © 2009 J. Parajka et al. 2009 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/13/259/2009/hess-13-259-2009.html The full text article is available as a PDF file from https://hess.copernicus.org/articles/13/259/2009/hess-13-259-2009.pdf

This study compares ERS scatterometer top soil moisture observations with simulations of a dual layer conceptual hydrologic model. The comparison is performed for 148 Austrian catchments in the period 1991–2000. On average, about 5 to 7 scatterometer images per month with a mean spatial coverage of about 37% are available. The results indicate that the agreement between the two top soil moisture estimates changes with the season and the weight given to the scatterometer in hydrologic model calibration. The hydrologic model generally simulates larger top soil moisture values than are observed by the scatterometer. The differences tend to be smaller for lower altitudes and the winter season. The average correlation between the two estimates is more than 0.5 in the period from July to October, and about 0.2 in the winter months, depending on the period and calibration setting. Using both ERS scatterometer based soil moisture and runoff for model calibration provides more robust model parameters than using either of these two sources of information.

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