Changes in Earth’s inner core will not have dramatic effect on magnetic field

A new study published in Nature Geoscience suggests that the rotation of Earth’s inner core might be slowing down. This conclusion is based on measurements of seismic waves studied by the authors at Peking University in China. This study also suggests that it may be an indication of a 70-year cycle of the core’s spin speeding up, slowing down, and changing direction. Why the inner core rotation changes is still an ongoing study.

But what does this mean for Earth’s magnetic field?

Dr Amoré Nel, Applied Geomagnetic Researcher at the South African National Space Agency (SANSA), says the Earth’s protective magnetic field is generated by its outer liquid core by a process called the ‘dynamo effect’. “This process would not be majorly affected by the change in rotation of the inner core and could at most contribute to some fluctuations in the magnetic field which is dynamic in nature.”

Computer simulation of Earth’s magnetic field.

The SANSA Hermanus Site has been monitoring and measuring the Earth’s magnetic field for over 80 years.

Daleen Fouche