1. Lamont-Doherty Earth Observatory; Columbia University; Palisades New York USA
2. British Antarctic Survey; Cambridge UK
3. School of Geographical Sciences; University of Bristol; Bristol UK
4. Bundesanstalt für Geowissenschaften und Rohstoffe (BGR); Geozentrum Hannover; Hannover Germany
5. Center for the Remote Sensing of Ice Sheets; Kansas University; Lawrence Kansas USA
6. U.S. Geological Survey; Denver Federal Center; Denver Colorado USA