The Earth’s liquid molten outer core, composed mainly of iron and nickel, generates an electromagnetic field extending from the north to the south pole, protecting the planet from harmful solar radiation.

Fluctuations in this magnetic field, caused by changes in solar wind and solar storms, affect geomagnetic field models essential for navigation in satellites, planes, ships, and cars.

Magnetic field models vary depending on data collected either on the Earth’s surface or from low Earth orbiting satellites.

While past research attributed differences in these models to space weather activity, a recent study published in the Journal of Geophysical Research: Space Physics reveals that modeling errors also contribute significantly to these discrepancies.

The University of Michigan research team analyzed six years of data from Earth’s magnetic field models and the Swarm mission’s satellites, finding that discrepancies occur even under low to moderate geomagnetic conditions, which prevail 98.1% of the time from 2014 to 2020, Phys.org reported.

These discrepancies, particularly pronounced in the polar regions, arise from the asymmetry between the magnetic fields of the northern and southern poles, contradicting the assumption of a symmetrical magnetic field.

This asymmetry, highlighted by differences in geomagnetic coordinates, complicates the creation of accurate magnetic field models.

The rapid changes in the polar magnetic fields over the past decade add further complexity to this task.

Understanding these model differences is crucial for improving geomagnetic field models and enhancing navigation accuracy for satellites and aviation.

The study underscores the importance of accounting for the Earth’s magnetic field asymmetry in future models to better navigate and understand the magnetosphere, ionosphere, and thermosphere.

Written by B.C. Begley