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Vorde
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Why do the magnetic poles line up (relatively speaking) with the poles of Earth's rotation?
OK - simplistically: the rotation of the core causes the field - imagine a system where the core rotates on an axis that is not the same as that for the overall rotation of the Earth... how would this happen?
Basically, the flows creating the dynamo effect are coupled to the Earth's rotation.
geo101 said:One important consideration is that at any given time (i.e., an instantaneous snapshot) the rotation and magnetic poles do not align. Take the present day field, for example, the poles do not align. If, however, you average over a period of time then the average magnetic poles will align with the rotation poles. How much time to average over depends on the availability and distribution (in space and time) of the data, but when all things are good several thousand years is enough time.
It would be pretty unusual for the angle between the rotational axis and the magnetic dipole to be close to 90deg though
I agree that this doesn't sounds not unreasonable, but what is the actual status of this statement? Conviction, Axiom? Hypothesis? Theory? Any true observations that would support it?
Ten degrees is pretty dang close, though. If the orientations of the rotation and magnetic axes were uncorrelated and random (which they aren't), the expected value of the misalignment would be 60 degrees.geo101 said:One important consideration is that at any given time (i.e., an instantaneous snapshot) the rotation and magnetic poles do not align. Take the present day field, for example, the poles do not align.
geo101 said:It does pass through 90 degrees during polarity reversals and some excursions.
This supported by a range of geomagnetic and paleomagnetic data. If you want to learn more look at http://magician.ucsd.edu/Essentials/WebBookse93.html#x109-18000014.5 from the http://magician.ucsd.edu/Essentials/index.html (a very good paleomagnetism book for those who are interested). The references in the chapter are good pointers for some more recent studies.
One of the primary assumptions in many paleomagnetic studies is that the magnetic field, when averaged over sufficient time, averages to that of a GAD (Geocentric Axial Dipole) field.
Bold mine. Doesn't this suggest that the status is "assumption"?
D H said:Ten degrees is pretty dang close, though...
Are we about to see some huge paradigm shifts?
Magnetic poles are the two points on the surface of the Earth where the planet's magnetic field is the strongest. These poles are known as the North Magnetic Pole and the South Magnetic Pole.
The Earth's magnetic poles have a strong influence on the planet's rotation. The magnetic field helps to stabilize the Earth's rotation and keeps it aligned with the Sun, which is essential for maintaining a habitable climate.
The magnetic poles are constantly moving, but they do not shift drastically. However, they do undergo small changes over time, and the North Magnetic Pole has been known to shift more rapidly in recent years.
No, the Earth's rotation is not perfectly aligned with the magnetic poles. This is because the Earth's magnetic field changes and shifts over time, causing the magnetic poles to move. Additionally, the Earth's rotation is also affected by other factors such as the gravitational pull of the Sun and Moon.
Scientists use various instruments such as magnetometers and satellite data to measure the alignment of the Earth's rotation with the magnetic poles. These tools allow scientists to track changes in the magnetic field and monitor the movement of the magnetic poles.