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bpeden99 t1_jdljdlg wrote

The Earth's magnetic field has been consistent in its dynamics over time, which is obvious. Can we still expect a flip in the future?


GeoGeoGeoGeo OP t1_jdlyu56 wrote


Over what duration of time? It's currently reducing in strength which has been interpreted by some as to be a reduction in strength from an anomalous high back to a more typical strength. Meanwhile there have also been long intervals of time with no reversals. These are known as superchrons, such as the cretaceous normal superchron which was an episode of stable polarity with little or no reversals lasting upwards of 37 million years. So long as the mantle and outter core keep thermally / chemicaly convecting we should expect the Earth's geodynamo to operate. This includes the possibility of excursions and reversals.


bpeden99 t1_jdlzf66 wrote

Magnetic north has been constantly and slowly changing since forever. They repaint airport runways because of that. I was under the impression it will violently flip eventually?


GeoGeoGeoGeo OP t1_jdm0dou wrote

It will never violently flip, that's just not how reversals or excursions occur. Reversals typically take anywhere between 4 and 9 thousand years to flip with the latest reversal taking 22 thousand years to reverse:

The magnetic pole wanders all the time. It's the intensity via gradual weakening that indicates an excursion or reversal.


bpeden99 t1_jdm0pjb wrote

I'm not sure about wanders, it's pretty consistent in moving north and northwest. But I understand the flip better, thank you