1. Institute for Electromagnetic Sensing of the Environment (IREA) National Research Council Milan Italy
2. Institute of Atmospheric Sciences and Climate (ISAC) National Research Council Cagliari Italy
3. National Institute for Nuclear Physics (INFN) Cagliari Italy
4. Polar Scientific Ltd Appin UK
5. Department of Civil and Environmental Engineering Clarkson University Potsdam NY USA
6. Department of Applied Mathematics and Theoretical Physics University of Cambridge Cambridge UK
7. Applied Physics Laboratory, Civil and Environmental Engineering University of Washington Seattle WA USA