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Updated: May 7, 2026
06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Electromagnetically driven westward drift and inner-core superrotation in Earth's core
Philip W Livermore1, Rainer Hollerbach, Andrew Jackson
1Schools of Earth and Environment and Mathematics, University of Leeds, Leeds, West Yorkshire LS2 9JT, United Kingdom.
Summary
A new 3D model links Earth's westward magnetic field drift to inner core superrotation. Changes in the magnetic field may drive inner core rotation and explain historical field drift directions.
Area of Science:
- Geophysics
- Earth Sciences
- Computational Modeling
Background:
- The Earth's magnetic field exhibits westward drift, and the inner core shows superrotation.
- Previous models have not fully explained the relationship between these phenomena.
Purpose of the Study:
- To investigate the link between Earth's magnetic field drift and inner core superrotation using a novel 3D numerical model.
- To explore the influence of core viscosity and magnetic field structure on geodynamic processes.
Main Methods:
- Developed a 3D numerical model of the Earth's core with significantly lower viscosity than previous models.
- Simulated the interaction of electromagnetic torques within the core.
- Analyzed the resulting fluid flow and inner core rotation.
Main Results:
- The model suggests a direct link between westward magnetic field drift and inner core superrotation.
- Axial electromagnetic torque influences core surface flow and imparts torque on the inner core.
- Variations in magnetic field structure can alter torque direction, potentially explaining historical field drift reversals.
Conclusions:
- Inner core superrotation's quasi-oscillatory behavior may be driven by decadal magnetic field changes.
- Periods of eastward magnetic field drift correlate with westward inner core rotation.
- A strong shear layer on the tangent cylinder may generate torsional waves within the core.
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