Why is the magnetic field getting weaker?

Answer 1

Thats a very good question, My theory is that the motion of the molten iron core is slowing. It has been proven that a spinning molten iron mass can generate a strong magnetic field. The earths core is a big blob of molten iron, courtesy of a large meteor that struck the earth millions of years ago which may i also add, gave birth to our moon. All this while the earth was still in its loosely packed formative years.

It sounds to me like the core is slowing after all these millions of years. The gauss level has dropped significantly over the past decade, and they predict that at the present loss rate, the magnetosphere will cease to exist. If that happens, the protection it offered us will also vanish and the solar wind will basically scrub our atmosphere away.. and we will wind up like mars...

Answer 2

I just wrote an essay about magnetic fields!

The Earth's magnetic field (any planet's magnetic field for that matter) is very complex. Just summarizing the basics, in the presence of a magnetic field, circulation of magnetic material will create an electric current. In Earth's case, this circulation is a result of convection in Earth's molten iron outer core. This electric current, since it is also rotating acts to perpetuate the magnetic field. (How the magnetic field started in the first place is still iffy.)

But the Earth's magnetic field is not constant. Scientist can study the paleomagnetic field by looking at rocks that formed a long time ago because when a rock cools from a magma state, the crystals in the rock align with the magnetic field and stay in that alignment until the rock melts again. Some controversial data from an ancient lava flow in Oregon suggests there was a period 16 million years ago when the magnetic pole could shift up to 6 degrees (latitude or longitude) in a single day.

More well documented is that the magnetic pole occasionally flips completely by shrinking from it's current state to zero, then growing in the opposite direction. This seems to happen in very irregular time intervals ranging from 5 thousand years to 50 million years. (The Sun is the only other celestial body we have been able to document such pole reversals in, mainly because the Sun has reversals regularly in 11 year intervals.)

Currently measurements indicate that the magnetic field is growing weaker and slowly drifting to the west (presently the magnetic north pole is near hudson bay and not at all aligned with Earth's rotational axis.)

The short of it all is that there could be innumerable reasons for the magnetic field weakening and science is not prepared to say anything definitive. Only as recently as 1995 did scientist even manage to construct a computer simulation of Earth's magnetic field, it's greatest accomplishment was that it managed to flip on its own similar to what Earth's field does on occasion. Follow-up and secondary studies are still underway, and no one is prepared to account for the small changes we are seeing today.

Answer 3

It appears to be part of the process of magnetic reversal, which is something that happens to the Earth on average every 250,000 years (and happened last 750,000 years ago). The magnetic field weakens so that parts of the Earth's surface show no appreciable magnetic field at all (a compass wouldn't work there). These areas become larger. At some point in the process the magnetic field reverses, and the geographical south pole becomes the magnetic north pole. At this point the magnetic field begins to strengthen and starts the cycle again.

As to why it happens, I think the correct answer is that nobody knows, although some people are beginning to think it is to do with sub-atomic processes going on in the Earth's core.

Answer 4

no longer for a "short-term" terraformation (tens of hundreds of years). An Earth-like ecosystem might itself take care of an floor existence from cosmic radiation - the lack of a magnetic field might grow to be severe only over the years by way of fact the photograph voltaic wind and cosmic rays stripped the ambience away, as is concept to have actual exceeded off in Mars's historical past. As has been reported above, the magnetic field situation is probable a rounding errors in the value of terraformation, and entirely irrelevant over the years frames as super as any previous human civilization has existed.

Answer 5

scientists believe that every once in a while the earths magnetic field shuts down and then restarts reversed (north = south). They do not have any real idea as to why this happens but they theorize that this could have been the cause of several mass extinctions.

Answer 6

I won't goof about this one:

Some researchers say that the polarity of the magnetic poles of the earth have change positions every few thousand years or so.
I saw it once on Discovery Channel, look it up.

Answer 7

Because the field is bigger and bigger in the external path. So the energy is deal to big area. The field become weaker.

Answer 8

Second law of theromdynamics all things lead to greater entropy (more disorder) also the Rapture and the end of the world is coming.

Answer 9

because its transferring magnetic energy to one of the objects? Not sure!

Answer 10

Because the world is slowly slowly start to spin slower.