Earths magnetic field?

Question

Ever since the compass was invented, navigators have noticed that the direction indicated by the needle changes slightly each year. Over the last century, both the north and south magnetic poles have been drifting north (that is, toward the geographic north pole, which itself wanders somewhat, but let's not make this more complicated than it already is). The north magnetic pole historically has moved at a rate of about ten kilometers per year, but has lately accelerated, heading toward Russia at four times that rate.


ANyone have any clues or good support evidence into when this would occur?

Sorry i ment to ask that the poles would shift, ie drastic change to earths axis!

Answer 1

Yes, wandering of the magnetic poles is not unusual.

When will the poles reverse? Unfortunately, there is much hype about this being presented lately due to 2012 disinformation and the fact that uneducated and gullable persons can be made to believe in almost anything that they don't understand. The internet is proving to be as much a detriment to education as a tool. A quick review of past reversals will show that they are in no way related to precession. The last reversal was the Brunhes-Matuyama reversal approximately 780,000 years ago.

A reversal of the poles is NOT imminent.

Some fanatical persons manipulate the figures to presume an impending reversal but such is not the actual case. Earth's field strength has been dropping in the last 150 years but it is still ABOVE the 2,000 year average. IF THE DROP CONTINUES AT PRESENT PACE, a reversal may be anticipated between 3000 and 4000 AD.

There is no reason, however, to anticipate such a continued decline.

An instantaneous measurement of it, or several measurements of it across the span of decades or centuries, is not sufficient to extrapolate an overall trend in the field strength. It has gone up and down in the past with no apparent rhyme or reason.

What if a pole reversal DID happen? There is no evidence of biological extinctions as a result of pole reversal. Items relying on electricity and electromagnetics (e.g. radio, satellite communications) may be vulnerable to technological disruptions.

Choose your science websites wisely.

Answer 2

Actually, the magnetic poles have changed quite a bit in the past, and evidence from lava flows suggest that the poles reverse every 250,000 years or so (not on a fixed schedule; that number is just an average).

To the best of my knowledge, the mechanism that causes pole reversal is not understood. We also are unable to predict when the next one might happen.

I have to disagree with a previous post about the effect of a pole reversal being limited to compasses. Many animals are sensitive to magnetic fields. It's possible that migratory birds, for example, use the magnetic field to find their way.

Also, if the field is minimal while it's reversing (which could be), then it won't be protecting us from the solar wind during that time. The atmosphere will protect us here on the ground, but there would be serious radiation damage to spacecraft in earth orbit.

Answer 3

the sector is equivalent to that of a bar magnet, yet this similarity is superficial. The magnetic container of a bar magnet, or the different variety of everlasting magnet, is created by making use of the coordinated spins of electrons and nuclei interior iron atoms. The Earth's middle, besides the shown fact that, is warmer than 1043 ok, the Curie component temperature at which the orientations of spins interior iron exchange into randomized. Such randomization reasons the substance to lose its magnetic container. hence the Earth's magnetic container is led to not by making use of magnetized iron deposits, yet greater often than not by making use of electric currents interior the liquid outer middle (because it spins, electrons tend to stay at the back of, hence producing a small contemporary). yet another function that distinguishes the Earth magnetically from a bar magnet is its magnetosphere. At large distances from the planet, this dominates the exterior magnetic container. electric currents brought on interior the ionosphere additionally generate magnetic fields. this variety of container is often generated close to the place the ambience is closest to the sunlight, inflicting daily adjustments which could deflect floor magnetic fields by making use of as much as a minimum of one degree.

Answer 4

poles shifting has nothing to do with the earths axis. a shift of the magnetic poles would have really no effect on life at all, besides compasses not working.

the magnetic poles have shifted several times in earths past. it will do it again someday, its not going to hurt us at all.

Answer 5

since plate tectonics move,changing the stucture of the planet, it might have to do with changing the poles of the earth. Like Everest grows a bit each year having it's summit higher.

Answer 6

True what he says... but how are you sure its 10 km each year? o.o

Answer 7

no, but I've got a cool video that can answer some of your questions
http://video.google.com/url?docid=3902466783636795302&esrc=sr1&ev=v&len=3357&q=earth's%2Binvisible%2Bshield&srcurl=http%3A%2F%2Fvideo.google.com%2Fvideoplay%3Fdocid%3D3902466783636795302&vidurl=%2Fvideoplay%3Fdocid%3D3902466783636795302%26q%3Dearth%2527s%2Binvisible%2Bshield%26total%3D7%26start%3D0%26num%3D10%26so%3D0%26type%3Dsearch%26plindex%3D0&usg=AL29H20m81UZTUHKzczJxri7JDSwtpeRyA

I'm assuming 300 years