1. Estellus; Paris France
2. LERMA; Observatoire de Paris; Paris France
3. Water Center; Columbia University; New York New York USA
4. Institute for Geophysics and Meteorology, University of Cologne; Cologne Germany
5. Department of Computer Science, Electrical and Space Engineering; LTU; Lulea Sweden
6. Global Environmental Measurements and Modeling; Chalmers University of Technology; Gothenburg Sweden
7. Earth Observation Projects Department; ESA, ESTEC; Noordwijk Netherlands