What is the effect of a geomagnetic reversal?

Answer 1

this is a really good answer that i found on a different sight. :

An impending magnetic, or pole, reversal was one of the hot topics of

the 80's when the book "Pole Shift" by John White was a best seller

and it was thought that it might happen any time now.

As with most prophesies around the end of the twentieth century, the

sense of impending doom has lessened and the pole shift "warning" has

been downgraded to a pole shift "watch"

But this is one of those things that are very probably going to happen

at some point "soon" in the earth's history....it's just that mankind

has a very small view of the overall earth clock, and to the earth,

"soon" could mean anytime in the next 100,000 years, so don't hold

your breath. Scientists currently tell us that pole shifts occur, on

average, once every 500,000 years. The last pole shift was 780,000

years ago so we are overdue for one (just as we are overdue for a big

asteroid strike, and for a super volcano eruption....just hope they

don't all happen at once!)

The planet's geologic record has very clear evidence that pole shifts

have occurred many times in the past and there is no doubt that they

will occur again. ( The phenomenon referred to here as a "pole shift"

is not the shifting of the crust by thousands of miles, but rather,

changes in the magnetic field of the planet. Some unscrupulous writers

in the 70s and 80s tried to imply that the continents were going to

start sliding about like melting ice on a hot plate, but that's not

current scientific thinking.)

However, its not all good news. Until recently, it was thought that

pole shifts were a gradual process. But recent evidence from studying

the alignment of iron particles in lava flows found one case where the

Earth's magnetic field shifted 80 degrees in 13 days.

What would a pole shift do to life on Earth?

Compasses would obviously be effected as would all navigational

instruments which depend on them. So shipping, air-flight and all GPS

equipment, including satellites, would be off-line until we figured

out how to cope with the reversal. Global trade would be brought

quickly to a standstill, and the winners would probably turn out to be

those that remembered how to navigate in the old ways, such as nomadic

people and sea-farers on old sailing ships

Migratory birds, fish and animals would become confused. This might

lead to them wandering far from current feeding and breeding grounds,

into areas not suitable for them, and could quite easily be concieved

as leading to mass extinctions, habitat destruction and loss of life,

both animal and human.

While this latter theory is controversial, scientists have already

shown that insects can actually be killed as a result of fluctuations

in magnetic fields around them, and the same experimenters have shown

similar, though smaller, effects in humans, leaving them dazed and

confused. If you consider the number of humans involved in operating

machinery that would be life-threatening in the case of faulty

operation, you can see that global effects would probably be large.

In addition large scale fluctuations in magnetic fields would knock

out power suppliers, and all electro-magnetic communication could

concievably be disrupted for long periods of time.

A rapid magnetic reversal would include very large scale fluctuations

in the Earth's magnetic field, which extends out 60,000 km from the

surface of the planet. It is also thought by many doomsayers that a

diminished magnetic field which shields us from energetic particles

emitted continuously by the sun would leave us vulnerable to the

harmful effects of magnetic storms spawned by solar flares and sun

spots. This would probably be hazardous to our health :)

BUT the magnetic field does not protect the earth from solar flares.

It simply

guides the ions of the solar wind to the polar regions, where their

energetic collisions with the upper atmosphere produce the luminous

plasma

known as the Northern and Southern Lights (Aurora Borealis and Aurora

Australis). It is the earth's atmosphere that actually prevents the

solar

wind from reaching the surface, and that is independent of the

magnetic field.

It is thought by some geologists that a rapid switch in the magnetic

field could lead to stresses in rock strata and lead to major

earthquakes and volcanic eruptions, with the possible scenario of the

"Ring of Fire" all going off at once and sending the world into

nuclear winter.

So, if you consider a world with no TV, radio, telephones (fixed or

mobile), computers, shop-tills, no planes,no ships, no radar, no air

traffic control, where weapons of mass destruction were likely to go

off without human intervention, and nuclear subs suddenly started

spontaneously exploding while aged power stations lost all their

regulatory barriers, you'll get an idea of the possibilities. Think of

all the disasters they were warning about for the so called "Millenium

Bug" in 2000, then imagine them all actually happening.

Then imagine the earth shaking, hot ash falling on your head, a tidal

wave approaching, and a migratory herd of Wildebeest turning up on

your doorstep.

As for the UN....they'd pass a resolution against it, but it would

happen anyway. But what else is new?

Hope that answers your question

Answer 2

During a geomagnetic reversal, the Earth's magnetic field weakens and changes direction. This can lead to disruptions in navigation systems, animal migration patterns, and satellite operations. However, these events occur over thousands of years and are not likely to have immediate catastrophic effects on life on Earth.