Science

MIT study asserts that there is little risk of Earth's geomagnetic field flipping in the near future

MIT study asserts that there i...
MIT graphic displaying a flip of the geomagnetic field
MIT graphic displaying a flip of the geomagnetic field
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MIT graphic displaying a flip of the geomagnetic field
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MIT graphic displaying a flip of the geomagnetic field

A new MIT studysuggests that there is little danger of Earth's geomagnetic fieldflipping in the near future. Previous research in the area hadpredicted an imminent flip (in geological terms) that would leave alllife on Earth temporarily un-shielded from a plethora of dangers posedby deep space phenomenon.

Generated from deepwithin our planet, Earth's geomagnetic field acts as a protectiveshield, guarding us from dangerous space weather and chargedparticles that would otherwise pose a dire threat to life on Earth.An analysis of rock samples has informed us that – seeminglyunpredictably throughout Earth's history – the geomagnetic fieldflips, leaving it temporarily unprotected.

During thistransitional period, which could endure for several thousand yearsbefore the field reasserts itself enough to regain its protectivequalities, we as a species would be exposed to a vast increase insolar radiation that could potentially cripple our technology andcreate severe genetic mutations.

The last recorded fliptook place roughly 780,000 years ago, and based on data collectedfrom the ground and in orbit has suggested that Earth's geomagneticfield has been in steady decline for roughly 200 years, leading someto predict that the field may flip again in around 2,000 years.

The new MIT-ledresearch may lead to a dramatic rethink of this model. The teambehind the research was able to accurately deduce the average fieldintensity for the past five million years based on an analysis ofvolcanic rock samples collected from the Galapagos Islands locatednear Earth's equator, and further samples extracted from Antarctica.

It was discovered thatthe strength of Earth's geomagnetic field during shielding periodshad an average intensity of 15 microtesla at the equator, and 30microtesla at the poles. The present day strength of the geomagneticfield has been measured at 30 microtesla at the equator and 60microtesla at the poles, placing it significantly above thehistorical average.

Scientists behind theresearch believe that previous studies in this area had suffered froma fatal flaw, which led to the more ominous predictions of animminent field flip. Prior work had misinterpreted how volcanic rocksrecorded the presence of magnetic fields. For the new study,scientists corrected the error, and for the first time collectedequatorial samples, allowing for a more accurate estimation of theaverage ancient field strength.

This means that eventhough Earth's geomagnetic field is steadily losing intensity, itwill still take around 1,000 years to dip to the newly-definedhistoric average. From this point, it is possible that the field maythen stabilize and maybe even increase in strength. Further studiesare required to better understand the complicated characteristics ofour planet's geomagnetic field, and the potential threat that areversal could pose.

A paper on thediscovery is available online in the Proceedings of the National Academy of Sciences.

Source:MIT

6 comments
Mel Tisdale
Are we sure that the magnetic poles, instead of flipping, with the associated decrease in shielding capability, actually meander around the globe to their new, reversed polarity positions? The instantaneous shielding would remain about the same, but the magnetic 'imprint' would be lessened due to the reduced amount of time spent in any one location as the poles moved. There was a paper some time back that discussed the 'rapid' movement of the magnetic north pole that we were (still are?) experiencing.
Embols
Maybe torxs(black holes) follow, same dilemma, with a sort of Coriolis!
Mirmillion
I wonder if they still have it wrong? Could it be that a geomagnetic force which is too high could cause pole reversal? Something twice the historical average would seem to be 180 degrees out of sync and could just as easily collapse as settle at the supposed average.
Douglas Bennett Rogers
It looks like protection at the magnetic poles would come mostly from the atmosphere, which is why we see the aurora.
Robert in Vancouver
No no no. The science is settled and the geomagnetic fields will flip. I'm sticking with the methodology that created the global warming religion - after scientists do some research and develop a theory, that means the science is settled and new research cannot be debated or accepted.
Bob
Why worry? A meteor or major volcanic eruption will probably happen as well. That is, if a more likely event such as war, famine or a major pandemic doesn't get us first.