Scientists soundscaped Earth’s magnetic reversal 780K years ago

Earth spins, shifts, and now… flips?

Our planet’s gymnastics routine continues underneath our feet nearly every day, but researchers at the Helmholtz Centre for Geosciences in Germany recently mapped what they say is one of the most “drastic events in the evolution of Earth’s magnetic field” — the Matuyama-Brunhes reversal, which took place 780,000 years ago.

The magnetic field, which extends up into the atmosphere, is generated by a layer of ever-shifting liquid metals underneath Earth’s surface. It protects the planet’s inhabitants from extreme cosmic and solar radiation, but it has also been harnessed in various technological projects.

Using ice cores, sediment samples and marine specimens, the team constructed a model of the field pre-flip, and animated the reversal. Three violins, three cellos and a synthesizer make up the sonic side of the project, mirroring the lurching veer that happens as the fields are in flux.

Though the sound is almost pleasant at first, the reversal sees a sudden shift in tone, leading to what the team called a “disharmonic cacophony.”

Several years back, scientists tracking the planet’s geomagnetic fields began to notice some oddities, sparking panic among the general population. The abnormalities occurred mostly in the South Atlantic.

A magnetic switch of this size would have consequences, but primarily because society and technology are inextricable. GPS interference, power grid interruptions, and satellite failures are several of the most pressing issues that humanity would face.

“Based on similarities with the recreated anomalies, we predict that the South Atlantic Anomaly will probably disappear within the next 300 years, and that Earth is not heading towards a polarity reversal”, said Andreas Nilsson, a geologist at Lund University, in a study on a potential field reversal.

Since the 1830s, the intensity of Earth’s magnetic field has diminished by 10 percent, but according to experts at the United States Geological Survey (USGS), paleomagnetic studies show that during a reversal, it decreases by up to 90 percent.

“A reduced intensity in the magnetic field does not necessarily mean that a reversal is about to occur. Moreover, the decrease in intensity is not a dramatic departure from normal,” added the USGS. “For all we know, the field may actually get stronger at some point in the not-so-distant future.”

“Understanding these extreme events is important for their occurrence in the future, space climate predictions, and assessing the effects on the environment and on the Earth system,” said Sanja Panovska, a researcher from the Helmholtz Center for Geosciences.