1. Department of Earth Sciences ETH Zurich Zurich Switzerland
2. Department of Geology and Geophysics University of Utah Salt Lake City UT USA
3. Laboratory of Hydraulics, Hydrology and Glaciology ETH Zurich Zurich Switzerland
4. Institute of Geodesy and Photogrammetry ETH Zurich Zurich Switzerland
5. BSF‐Swissphoto Regensdorf‐Watt Switzerland