Future Change In Magnetic Polarity Of Earth

[gumboot]

I’ve recently read this statement:

//The Earth’s North/South poles flip polarity on a semi-frequent basis, having done so more than 20 times during the past 5 million years. This means that with the next flip, all compasses will be pointing South rather than North.//

Now that’s all very well, but my question is how will this affect devices which have specific North/South poles. Will electric motors be affected by the switch in polarity? I would have thought this would have a major effect on the population and wouldn’t simply necessitate painting the other end of a compass needle red.

I'd be grateful for any insight into this.

[Old_Geezer]

It's not going to effect your magnets.
It's just the Earth flipping pole position.
But things like compasses would point to where is now south rather than where is now north.

[Hypognosis]

The earth's magnetic pole has "wandered", to a measurable extent ever since map makers first started being concerned with a grid for position reference purposes. The reference grid is arbitrary and more about clear communication than correctness about where compasses say north is. Hence your Ordnance Survey map shows a small chart of how to relate magnetic north, true north and grid north. With it is a comment about how many degrees and whether eastwards or westwards, magnetic north is expected to drift in the next five years.

When the pole-flip does occur, it may take decades to fully reverse and there may be years of annoying random wandering in the interim. We have satellites and GPS now so serious users of navigation equipment will not likely be affected. Some ramblers, in serious wilderness settings may get into difficulty when their phone battery goes flat but they'll soon adapt to using sun and stars for alternative directional guidance.

Migratory birds might be badly affected but it is only weakly proved that they are dependent on sensing earth's magnetic field, so take that with a pinch of salt.

[mibn2cweus]

Electric motors rely on their own permanent and induced magnetic fields that are not significantly affected by the overall much weaker and widely spread magnetic field generated within the Earth. Only devices which depend directly and solely on the Earth's magnetic field would be affected by alterations in its alignment.

[mibn2cweus]

Smartphones have software which uses current geomagnetic declination maps along with gps and base station triangulation to work out where true north is.

http://britgeopeople.blogspot.com/2013/11/how-do-smartphones-work-out-what.html

[gumboot]

Thank you all for the information.