Geomagnetic Jerks: Rapid Core Field Variations and Core Dynamics

• Published in: Space science reviews Vol. 155; no. 1-4; pp. 147 - 175
• Main Authors: Mandea, Mioara, Holme, Richard, Pais, Alexandra, Pinheiro, Katia, Jackson, Andrew, Verbanac, Giuliana
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Dordrecht Springer Netherlands 01.08.2010; Springer; Springer Nature B.V; Springer Verlag
• Subjects: Aerospace Technology and Astronautics; Artificial satellites; Astrophysics and Astroparticles; Data analysis; Earth, ocean, space; Exact sciences and technology; Geomagnetic field; Geophysics; Magnetic fields; Physics; Physics and Astronomy; Planetology; Sciences of the Universe; Space Exploration and Astronautics; Space Sciences (including Extraterrestrial Physics; Time series; Core field; Geomagnetic jerks; Secular variation; Core flows; Sudden variation; Dynamics; Correlations; Space remote sensing; Geomagnetic field; Regional scope; Time series; Secular variations; Satellite observation; Fast variation; Observables; Time variation
• ISSN: 0038-6308; 1572-9672
• DOI: 10.1007/s11214-010-9663-x

The secular variation of the core field is generally characterized by smooth variations, sometimes interrupted by abrupt changes, named geomagnetic jerks. The origin of these events, observed and investigated for over three decades, is still not fully understood. Many fundamental features of geomagnetic jerks have been the subject of debate, including their origin internal or external to the Earth, their occurrence dates, their duration and their global or regional character. Specific tools have been developed to detect them in geomagnetic field or secular variation time series. Recently, their investigation has been advanced by the availability of a decade of high-quality satellite measurements. Moreover, advances in the modelling of the core field and its variations have brought new perspectives on the fluid motion at the top of the core, and opened new avenues in our search for the origin of geomagnetic jerks. Correlations have been proposed between geomagnetic jerks and some other geophysical observables, indicating the substantial interest in this topic in our scientific community. This paper summarizes the recent advances in our understanding and interpretation of geomagnetic jerks.