Catherine Ottlé
Sylvie Mascle-LeHégarat
10 Avenue de l'Europe
78140 Vélizy
Tél : 33 1 39 25 49 12
Fax: 33 1 39 25 49 22
Email :

The group "Study of continental interfaces" at CETP, which will be involved in the work is composed of 4 researchers and 4 PHD students. It is specialized in the study of the land-atmosphere interactions for hydrology and agronomy studies. It has two main research activities related with the proposal subject. They are based on the synergistic use of optical, thermal infrared and microwave remote sensing data to infer atmospheric and surface parameters. In this domain, different researches have been done these last ten years to improve land surface temperature retrievals from thermal infrared data : development of algorithms correcting the atmospheric effects, interpretation of angular variations of radiative temperature and use of dual incidence measurements to separate vegetation and soil contributions. These works have been published in international journals and presented in different scientific meetings.

Since the last ten years, we are involved in scientific programs in radar microwave and optical remote sensing and developed methodologies to account such data for the temporal follows up of energetic and hydric soil budgets. Modelisations of the electromagnetic diffusion by crop canopies in the microwave domain as well as modelisation of the radiative transfer in the thermal infrared have been developed to improve the retrieval of surface and vegetation parameters from space like soil moisture and vegetation indexes. We have also a good experience in using these data in SVAT models coupled with distributed hydrological models or with rainfall-runoff models.

The following key personal will be involved in CETP's contribution to the proposal :

Catherine Ottlé : Research scientist in the CNRS since 1985. She received the M.S and Ph.D. degrees in Physics from the University of Paris, Paris, France, in 1981 and 1983 respectively.
Her resarch interests include the applications of remote sensing to the study of the land surface processes for hydrology and vegetation monitoring at local and regional scales. In particular, she is working on the development of SVAT modelisations for remote sensing data assimilation and on large scale hydrology on the occasion of her participation to Hapex-Mobilhy and Alpilles-ReSeDA programs and to ERS-ESA pilot projects. These activities are done in close collaboration with other Public Research Institutes or Organisations, aerospace companies and industry of the added value in remote sensing. She is also involved in thermal infrared remote sensing research activities : modelling of radiative transfer in the atmosphere, atmospheric and emissivity correction methods, land and sea surface temperature determination.

Sylvie Mascle-LeHégarat : Junior lecturer at Versailles-Saint-Quentin University. She graduated from the Ecole Nationale Superieure des Telecommunications (ENST), Paris, France, in 1993, and received the PhD degree in Signal and Image from ENST in 1996. She is specialized in imagery processing (SAR and optical data) and data fusion. Her research interests are the identification of land cover structures as well as functional entities for the retrieval of hydrological parameters. She currently works on surface soil moisture estimation at watershed scale from combination of multispectral SAR series and thermal infrared images and on the assimilation of these data in hydrological models.

Le Hegarat-Mascle, S., I. Bloch, D. Vidal-Madjar, 1997, Application of Dempster-Shafer Evidence Theory to Unsupervised Classification in Multisource Remote Sensing, IEEE Transactions on Geoscience And Remote Sensing, vol.35, no.4.

Le Hegarat-Mascle, S., D. Vidal-Madjar, O. Taconet, M. Zribi, 1997, Application of Shannon Information Theory to a Comparison between L and C band SIR-C Polarimetric Data versus Incidence Angle, Remote Sensing of Environment, vol.60, no.2,.

Le Hegarat-Mascle, S., D. Vidal-Madjar, P. Olivier, 1996, Application of Simulated Annealing to SAR Image Clustering and Classification Problem, International Journal of Remote Sensing, vol.17, no.9.

Ottlé, C. , D. Vidal-Madjar, A.L. Cognard, C. Loumagne, M. Normand, 1996,Use of vegetation and soil variables inferred from radar and optical remote sensing in hydrological modelling, Scaling-up hydrological variables using remote sensing, John Wiley & Sons Ed., pp.221-235.

François, C. and C. Ottlé, 1996, Atmospheric corrections in the thermal infrared : Global and water vapour dependent Split-Window algorithms. Application on ATSR data, IEEE Trans. Geosci. Remote Sen., 34, 2, 457-470.

François, C. , C. Ottlé and L. Prévot, 1997, Analytical parameterization of canopy directional emissivity and canopy directional radiance in the thermal infrared. Application on the retrieval of soil and foliage temperatures using two directional measurements. Part 1 : Theory, Int. J. Remote Sensing, 18,12, 2587-2621.

Role in the SMOS mission:

Algorithm development for Soil moisture retrieval and assimilation procedures in the surface schemes of hydrological models validation of the algorithms on the experimental river basins .