The geomagnetic field - a tool for exploring the Earth's interior – Niels Bohr Institute - University of Copenhagen

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The geomagnetic field - a tool for exploring the Earth's interior

Inaugural Lecture: Adjoined professor Nils Olsen

Niels Bohr Institute

The launch of the Ørsted satellite almost 10 years ago marked the beginning of a new era in the exploration of the Earth's magnetic field from space. Data of unprecedented resolution and spatial coverage have been collected by Ørsted and follow-on missions. These observations provide valuable information about the interior of our planet as well as its environment.

The observed magnetic field contains, however, a superposition of contributions from different sources: the core field caused by the geodynamo in the Earth's interior, magnetized rocks in the Earth's crust, electric currents in the ionosphere, magnetosphere and oceans and by currents induced in the Earth by time-varying external fields powered by the sun. The scientific challenge is to separate these contributions and to interpret the signatures of the different processes they represent.

The lecture is devoted to the various steps needed to explore the geomagnetic field from space: from the measurements taken by satellites to data processing and interpretation of the results. Emphasis is placed on studies of the core magnetic field when it undergoes particularly rapid time changes.

Earth and Planetary Physics is host for a reception after the lecture.