The Earth is a magnet. Its dipole character from e results massive currents within the molten portion of its core. These currents, presumably by gravitational in driven i energy, induce, the manner of a self-sustaining dynamo, a global dipolar magnetic field with t a magnitude of rouehly g 0.7 gauss at the gne ti poles. Although the ancient Chinese were familiar with the polar alignment of magn...

Geomagnetic indices are basic data in Solar-Terrestrial physics, and for operational Space Weather activities. The International Service of Geomagnetic Indices (ISGI) is in charge of the derivation and dissemination of geomagnetic indices that are acknowledged by the International Association of Geomagnetism and Aeronomy (IAGA, an IUGG association). Institutes which are not part of ISGI started...

Assessment of the actual geomagnetic activity level from local magnetometer monitoring is of importance in earth sciences and exploration but also for different kinds of risk assessment with regard to electronics and electric power facilities. Wavelet based signal processing methods are applied to extract meaningful information from magnetic field time series in a noisy environment. Using a pro...