1. Norwegian Polar Institute; Tromsø Norway
2. Department of Physics and Technology; University of Tromsø; Tromsø Norway
3. Department of Geosciences; University of Oslo; Oslo Norway
4. National Snow and Ice Data Center, CIRES; University of Colorado at Boulder; Boulder Colorado USA
5. Cryospheric Science Branch; NASA Goddard Space Flight Center; Greenbelt Maryland USA
6. Thayer School of Engineering; Dartmouth College; Hanover New Hampshire USA