Just when we thought we had enough to worry about, scientists noticed that the north magnetic pole was moving away from the true north pole into Siberia Despite recent political conflicts, it was not the location the magnetic pole was moving to that was the problem – it was the fact that geological history shows this is an indication the Earth’s magnetic poles are in the process of reversing themselves … and that could screw up something we’ve grown to love and consider indispensable – global positioning systems (GPS). At the same time, the south side of the planet discovered something scarily called the South Atlantic Anomaly – a huge area of Earth's inner Van Allen radiation belt that is messing with satellites and spacecraft by exposing them to higher-than-usual levels of radiation. All of this is also tied to the magnetic poles. Is it time to push Elon Musk to drop buying Twitter and build the [email protected] giant spaceship to Mars already?
“We have mapped changes in the Earth’s magnetic field over the past 9,000 years, and anomalies like the one in the South Atlantic are probably recurring phenomena linked to corresponding variations in the strength of the Earth’s magnetic field.”
A good scientist looks to see if an event happened before and determine what the results were. Andreas Nilsson, a geologist at Lund University, is a good scientist – she explains in the press release for a new study (Nilsson is the lead author) published in the journal Proceedings of the National Academy of Sciences (PNAS) that, while the weakening of the magnetic field in the South Atlantic is a bad thing because it’s happening very quickly and it is a good sign of magnetic polarity reversal, it’s happened before and we’re still here. Obviously, that’s not enough to stop us from worrying, so she digs deeper. And by that we mean physically digging.
To obtain data about how the Earth’s magnetic field has changed over time, researchers use burnt archaeological artefacts like clay pots, volcanic samples and sediment drill cores which preserve magnetic field data from the time they were heated to extremely high temperatures. After capturing the data from the samples and artifacts, Nilsson fed the data into a model and found that there was a magnetic field weaking similar to the South Atlantic Anomaly around 1600 BCE and lasted for 1,300 years. However, it did not cause a magnetic pole reversal – the last one of those occurred 42,000 years ago. The model showed that the magnetic field weakened dramatically over time – fortunately, there were no satellites in orbit back then -- before restrengthening and returning to a normal balanced state. Matching the model up to the timeline of the present South Atlantic Anomaly, the study reached a conclusion:
“We propose that the period around 600 BCE, characterized by a strongly asymmetric field, could provide an analog to the present-day field. The analogy implies that the South Atlantic Anomaly will likely disappear in next few hundred years, accompanied by a return to a more symmetric field configuration and possibly, a strengthening of the axial dipole field.”
So, satellites, planes and ships need to continue to avoid the South Atlantic Anomaly for a few more centuries, but we can rest comfortably knowing the magnetic poles aren’t in reversal and we won’t be suffering from a worldwide highly-charged particle bombardment by the Sun due to a weak magnetic field, causing disruption and potential destruction of the other thing we hold near and dear to our hearts – the Internet.
Does that make you feel any better? While not a guarantee, Nilsson’s model is a strong forecasting tool showing good times ahead … at least with the magnetic poles and magnetic field. So, you don’t have to be nice to Elon Musk … yet.