High-quality observations have been obtained from a number of magnetic satellites, complementing the ground available data for the last decade. We present here the issues regarding observatory and satellite data, in order to show how these modern measurements have brought new insights in understanding the Earth's magnetic field. It is only when combined with ground-based data that satellite measurements can provide additional opportunities for studies ranging from core flow, mantle conductivity and lithospheric composition to the dynamics of the ionospheric and magnetospheric currents. Therefore, in this paper a case is presented for the necessity of continuous monitoring of geomagnetic field from ground and space. This contribution is mainly based on some recent work and publications we are co-authoring.
Geomagnetic field, secular variation, secular acceleration, satellite measurements
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