Institution: | Geophysical Institute, University of Copenhagen, Haraldsgade 6, DK-2200 Copenhagen N, Denmark,; Danish Meteorological Institute, Lyngbyvej 100, DK-2100 Copenhagen E, Denmark,; Electromagnetic Institute, Technical University of Denmark, DK-2800 Lyngby, Denmark;and British Antarctic Survey, High Cross Madingley Road, Cambridge CB3 0ET, England |