1. Division of Hydrologic Sciences; Desert Research Institute; Reno Nevada USA
2. Center for Ice and Climate, Niels Bohr Institute; University of Copenhagen; Copenhagen Denmark
3. Department of Physics; Curtin University; Perth Australia
4. British Antarctic Survey; Madingley Road, High Cross, Cambridge, Cambridgeshire United Kingdom
5. Alfred-Wegener-Institut für Polar- und Meeresforschung; Bremerhaven Germany