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What is magnetic pole reversal exactly? In 1962, a man named Hess was trying to prove sea floor spreading theory. Huge mountains were found in the middle of the ocean (biggest in the world in some parts), and his theory was that basalt lava came up there and cooled, and later pushed the outer basalt layers further apart like in this picture:
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I'm getting to a point, don't worry. In this theory, the newest rock would be right where it forms at the crack and the oldest rock would be furthest away from the crack. At the time, it was difficult to test the age of a rock through drilling and such, so another method had to be formed.

Layers of rock with relative distances from the crack were oriented different ways to become magnets. While the lava cools, the rock orients itself towards the magnetic north. Well, turns out the magnetism of the poles CHANGE over the course of around 2000 years. In other words, magnetic north is sometimes north and other times south depending on the period of the earth's history.

Nobody knows why the magnetic north switches sides every 2000 years or so, but this was used like the rings in a tree to determine the age of rocks away and near the crack which supported Hess's theory that we use today. We've been so used to magnetic north for so long, it hasn't crossed our minds to think it hasn't always been that way. In fact, we are long overdue for a magnetic reversal. It has been 6000 years since the last one.

Scientists suggest that the magnetic reversal is happening now! Over the last decade, the magnetism has reduced by 10%, and at this rate, magnetism will be nonexistant within 90 years or so. Who cares right? Well there has been a very noticeable trend of extinctions and evolutions associated with these magnetic reversals. Half-way when the magnetism is 0 on its way to reversal, there won't be anything to block the sun's rays, and the UV rate will be incredibly high. This is why, they think, that the ozone layer is being depleted slowly.

Throughout written human history, we haven't had one of these occur in so long that we dont' know what to expect. Could this magnetic reversal trigger the extinction of some species? Or even more ingreguing, could this trigger the evolution of species? Is evolution possible, and is this the missing piece of the puzzle?

If the world should blow itself up,the last audible voice would be an expert saying it can't be done

This post was edited by Hawkeye on Nov 14, 2002.

Hmmmmmm from what I've read, they haven't really found much effect of it in the fossils, etc. from the other instances.

Since the liquid outer core of earth, mostly iron, moving around is the basis of the electrical magnetic that creates our magnet, I'm wondering if the shape of earth itself may have a bit to do with it.

Now that the ice age has melted off....earth is kinda reforming itself from the kinda pear shaped southern bottom heavy shape she's been in.

We are essentially a gyro-whipping around out here....and one that is not a perfect sphere. We get tipped at certain times, get us a bit of a wobble going on. Got Quasars out there affecting our axis, the moon and sun pulling on us, the solar wind kinda thin then thick at times pushing and forming our atmosphere and magnetic field. And we can't know, yet, the changes happening in their neighborhoods that effect them. Lol.....giving us a tail, too, which (play on words here) hasta be kinda a drag at times.

Our core isn't even a nice round sphere...kinda elliptisoid.

Granted, it is a frightingly fast change of nature by all accounts..

Insects and animals that use the poles for direction and distance....will adapt I bettcha.

We are seeing more ummmmmmmm action in plates and volcanoes etc. A planet in a aging spurt??

quis custodiet ipsos custodes?

Just an interesting note: due to the pole switching, what we actually see as north on a compass is magnetic south. And the magnetic south is 17 degrees off true north.

One species that would be affected by a pole switch is homing pigeons. They actually navigate by magnetism. If the poles reversed, they would all end up in the wrong place.
On the other hand, a pole switch might be a subtle, drawn-out process, so evolution would have a chance to gradually change homing pigeons to deal with new circumstances.

No doubt there would be other, similar cases. But if the poles change rapidly, then it is possible that the dramatic change in environment would be catastrophic.

Not to mention the effects on compass-makers.

you can come to terms and realize, you're the only one who cannot forgive yourself -Pearl Jam

Not to mention the effects on compass-makers.

You don't have to worry about them. They are going to have a great time fixing everyone's compasses. Just like the Y2K bug fixes before the new millenuim, every compass-maker will make a lot of money fixing the MPR bug (Magnetic Pole Reversal bug) :) by switching the labels from N to S, and from S to N and so on.

Love is blind, but marriage is a real eye opener.

They are going to have a great time fixing everyone's compasses.

Exactly. I have no doubt that they will earn a great deal of money.

Sheesh. One would think that I said that compass makers would become extinct.

you can come to terms and realize, you're the only one who cannot forgive yourself -Pearl Jam

No doubt there would be other, similar cases. But if the poles change rapidly, then it is possible that the dramatic change in environment would be catastrophic.

You're wrong. A rapid change would be less catastrophic - the fact is the change will not be rapid - the change is already occuring.

It is possible to measure areas in the southern hemisphere with magnetic properties that are north aligned and similaraly in the northern hemisphere southerly aligned magnetic areas. There are in effect areas of magnetic anomoly on each hemisphere. These areas are growing and increasing in number. Eventually their strength will be such that there will in effect be several magnetic poles (compass manufacturers aren't going to be able to do shizz about that). The switch will take just as long to finish with areas gradually becoming all south - or all north - and the anomolous areas disappearing. All this could take a thousand years or so.

Over this period protection from charged solar particles will be negligable - currently the aurora at the poles are caused by these particles being funneled by the magnetic influence of the earth to these areas and then producing light as they ionise the atmosphere. There will in fact be numerous aurora at each of the unstable magnetic poles.

Thanks for this very visual explanation.

There are in effect areas of magnetic anomoly on each hemisphere

What is the nature of such anomalies? Do they center around a given point or is a whole area acting as a magentic pole?

Eventually their strength will be such that there will in effect be several magnetic poles

How far would that effect be noticable? Isn't their strength negligible compared to the "real" pole, unless you're standing very close to such an area?

These areas are growing and increasing in number.

How must I imagine standing on the outer edges of such an area? Do they have sharp edges anyway?

Sorry for all these questions. I'm curious.

'Yeah, That's what Jesus would do. Jesus would bomb Afghanistan. Yeah.' - snowlion

What is the nature of such anomalies? Do they center around a given point or is a whole area acting as a magentic pole?

Imagine a contour map - magnetic strength and orientation can be visualised using these contours. In a normal alignment the northern and southern poles would be the strongest orientiented to magnetic south and north (obviously). Over time the 'border' between north and south along the magnetic equator becomes less clear - the countours become curved such that southerly aligned areas move north and vice versa. Now imagine areas that curve so much that they form a completely seperately aligned area within a hemisphere. You would have an anomly within one of the hemispheres. The effect of which is to negate the aggregate magnetic field - hence the magnetic field appears weaker.

How far would that effect be noticable? Isn't their strength negligible compared to the "real" pole, unless you're standing very close to such an area?

You would have aurora at each of these poles - hence it would be very noticeable. There would no longer be a real pole as the aggregrate magnetic force would no longer have a strong alignment.

How must I imagine standing on the outer edges of such an area? Do they have sharp edges anyway?

It would be gradual - you would not have an area of exceedingly high northern alignment sitting in the middle of an area of exceedingly high southernly alignment - naturally would would expect them to interface as they would interact.

The idea of the contour map made it clear. Thanks for explaining!

'Yeah, That's what Jesus would do. Jesus would bomb Afghanistan. Yeah.' - snowlion

Since we, have no effect upon the movements of the Globe, Earth.
Seeing the Earth in empty space, floating being effected only by the Sun & Moon...Its magnetic movements, which are unseen & not seen as edges or as lines but a force, picture the Earth as a ball of water floating in space & the Sun a ball of Fire. Floating in space, effecting the waterball & its movements, its magnetic core, yet understanding still, nothing on the planet has effect on these forces at all, While the Sun itself, changing Its magnetic poles, It seems - "the whole solar system" is a free moving topsy turvsy, functioning Storm, "if you will" While spinning round...its insides also are free moveing parts of this whole wheel or "Solar System" (Which by the way has no name, or if so, please let me know.)
What & where could we see or find the center...edge...fixed..or moving to another point?...but in the understanding the effect of the Suns reversal on the Earth's Core.? And the reasoning behind the Event.