1. Glaciology Group, College of Science; Swansea University; Swansea UK
2. Cryospheric Sciences Laboratory; NASA Goddard Space Flight Center; Greenbelt Maryland USA
3. Seismological Laboratory; California Institute of Technology; Pasadena California USA
4. Faculty of Natural and Applied Sciences, Department of Mathematics; Trinity Western University; Langley British Columbia Canada
5. Institute of Geography and Earth Sciences; Aberystwyth University; Aberystwyth UK
6. Geological Survey of Denmark and Greenland; Copenhagen Denmark
7. Department of Earth Sciences; Uppsala University; Uppsala Sweden