Geographic and Magnetic Poles
The axis of the earth’s rotation rivets the earth’s geographic poles. On global maps, the north and south geographic poles pinpoint at the unison of lines of longitude. Earth’s geographic poles and magnetic poles lie at different places.
As all are the points on the earth, the northern magnetic pole is south of the north geographic pole (located on the polar ice cap) and currently positions near Bathurst Island north of Canada. The southern magnetic pole is displaced hundreds of miles far from the south geographic pole at the Antarctic continent.
Even though the axis of rotation fixes them, the geographic poles encounter a slight wobble like motions in a circular pattern that stints the poles approximately six meters per year. Axed on shifting polar ice, the North Pole, i.e. the geographic pole is technically specified as that point 90° N latitude, 0° longitude because all longitude lines converge at the poles. Any value of longitude can be swapped to indicate the same geographic point.
The South Pole, i.e. the geographic pole, is technically described as that point 90° S latitude, 0° longitude. Early explorers and scholars used satinets and took astronomical readings to calculate the geographic poles. Modern time explorers rely on global positioning system (GPS) coordinates to accurately measure the location of the geographic poles.
Earth’s magnetic field stretches over time, and gradually it completely reverses its polarity. There are pieces of evidence from the magnetic mineral orientations that suggest that- during the past 10 to 15 million years, reversals have occurred as often as at every quarter million years.
Even though the earth’s magnetic field undergoes a constant change (periods of strengthening and weakening), the last magnetic reversal happened approximately seven hundred fifty thousand years ago. So geophysicists state that the subsequent deterioration will not occur within the next few hundred or thousand years, the current alignment signifies that at the northern magnetic pole, a dip compass (a compass with a vertical swinging needle) arrows straight down. At the southern magnetic pole, the dip compass needle points straight up or at the pole.
The magnetic poles are deviating, i.e. not stationary. The north magnetic pole wanders or voyages about 10 kilometers per year. Since igneous rocks cool from the hot magma, the magnetic minerals align themselves with the magnetic polarity at the cooling time. These rocks conserve a history of magnetic reversals. And when they are discovered at equidistant banded patterns on one side of mid-ocean ridges, they offer paleomagnetic evidence of plate tectonics.
Navigators working with the magnetic compass measurements must make corrections for the distance between the geographic and magnetic poles as well as for the shifting of the magnetic poles. Additionally, the magnetic poles may encounter the displacements of 25 to 37 miles, i.e. 40 to 60 kilometers from their average location due to magnetic storms or other disturbances of the ionosphere and the earth’s magnetic field.
Angular rectifications for the difference between the geographic poles and their paralleling magnetic poles report as the magnetic declination. The figures for the magnetic declination fluctuates with the observer’s position.
The earth has two types of poles:
The two types of poles are geographic poles and magnetic poles. These two types of poles are near one another but do not locate in the same place.
The geographic poles are defined as poles of the earth and are the locations where the earth spins on its axis. These poles position at 90 degrees from the equator and positions in the Arctic Ocean. The geographic south pole positions on Antarctica.
The magnetic poles of the earth are the positions where the magnetic fields are the most powerful. They are close to the geographic poles but are not in the same location. The magnetic pole in the north positions slightly south of the geographic north pole. The magnetic pole in the south positions slightly north of the geographic south pole.
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