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C. Rüdiger, J.C. Calvet, T. Holmes, R. De Jeu, W. Wagner, A. Chanzy, J. Wigneron:
"Soil moisture observations from space - An analysis of existing data sets";
Poster: Catchment-scale Hydrological Modelling & Data Assimilation International Workshop (CAHMDA-III Workshop), Melbourne, Australia; 2008-01-09 - 2008-01-11.

This paper introduces two analyses undertaken in preparation for the work leading up to
the assimilation of SMOS observations into the SVAT model ISBA at Météo France. First,
inconsistencies between bare soil observations from MODIS and the vegetation data base used in
the forward model to retrieve soil moisture from SMOS are presented. Second, a comparison study
of different instruments providing surface soil moisture information (AMSR-E and ERS-Scat) is
undertaken with the reanalysis soil moisture predictions over France from the model suite SIM
(SAFRAN-ISBA-MODCOU) of Météo France. The results obtained from the first analysis show,
that the bare soil fractions of certain vegetation types are subjected to biases and low correlations,
which in practice would result in differences between the observed and modelled soil moisture
content, thus limiting the SMOS retrieval algorithm. The second analysis shows that a good
correlation exists between AMSR-E (VUA), ERS-Scat, and SIM for low altitudes and low-tomoderate
vegetation cover, with a reduction in the correlation in higher altitudes.