North Atlantic Hydro-Magnetic Loop GMF data:Institute fur Geophysik, Zurich & NOAA see also: http://www.vukcevic.talktalk.net/NFC1.htm More charts can be found here: Graphs and Formulae
see also: http://www.vukcevic.talktalk.net/NFC1.htm More charts can be found here: Graphs and Formulae