1. Department of Geophysics; University Centre in Svalbard; Longyearbyen Norway
2. Birkeland Centre for Space Science, Department of Physics and Technology; University of Bergen; Bergen Norway
3. British Antarctic Survey; Cambridge UK
4. National Centers for Environmental Information; Boulder Colorado USA
5. Institute of Physics of the Earth; Moscow Russia
6. SOA Key Laboratory for Polar Science; Polar Research Institute of China; Shanghai China
7. The Johns Hopkins University Applied Physics Laboratory; Laurel Maryland USA