1. Universitat de València,Image Processing Laboratory (IPL),Burjassot-Paterna,Spain,46100
2. Massachusetts Institute of Technology,Department of Civil and Environmental Engineering,Cambridge,Massachusetts,USA
3. Université de Bordeaux,INRAE, UMR1391 ISPA,Villenave d'Ornon,France,F-33140
4. Microwaves and Radar Institute,German Aerospace Center (DLR),Wessling,Germany,82234
5. University of Cambridge,Department of Geography,Cambridge,UK,CB2 3EN