Future — Pole Shift

The cataclysmic pole shift hypothesis is the conjecture that there have been rapid shifts in the relative positions of the modern-day geographic locations of the poles and the axis of rotation of a planet. For the Earth, such a dynamic change could create calamities such as floods and tectonic events. This type of event would occur if the physical poles had been or would be suddenly shifted with respect to the underlying surface over a geologically short time frame. This hypothesis is almost always discussed in the context of Earth, but other bodies in the Solar System may have experienced axial reorientation during their existences.

Among the scientific community, there is no research that indicates a rapid change in the position of the rotational axis. There is evidence of precession and changes in axial tilt, but this change is on much longer time-scales and does not involve relative motion of the spin axis with respect to the planet. However, in what is known as true polar wander, the solid Earth can rotate with respect to a fixed spin axis. Research shows that during the last 200 million years a total true polar wander of some 30° has occurred, but that no super-rapid shifts in the Earth's pole were found during this period. A characteristic rate of true polar wander is 1° per million years or less. Between approximately 790 and 810 million years ago, when the supercontinent Rodinia existed, two geologically-rapid phases of true polar wander may have occurred. In each of these, the Earth rotated ~55°.

True polar wander

True polar wander, or the motion of the solid Earth with respect to a fixed spin axis that causes the spin axis to lie over a new geographic position, does occur. This is because of changes in mass distribution throughout the Earth that modify its moment of inertia tensor. The Earth consistently readjusts its orientation with respect to its spin axis such that its spin axis is parallel to the axis about which it has its greatest moment of inertia. This readjustment is very slow. In 2001, historical evidence for true polar wander was found in paleomagnetic data from granitic rocks from across North America. The data from these rocks conflict with the hypothesis of a cataclysmic true polar wander event. This evidence indicated that the geographical poles have not deviated by more than about 5° over the last 130 million years. More rapid past possible occurrences of true polar wander have been measured: from 790 to 810 million years ago, true polar wander of approximately 55° occurred twice.

Causes and effects

True polar wander can be caused by several mechanisms of redistributing mass and changing the moment of inertia tensor of the Earth:

  • Glacial cycles: redistribution of ice and water masses, and resultant deformation of the crust, changes the mass distribution around the Earth.
  • Perturbations of the topography of the core-mantle boundary, perhaps induced by differential core rotation and shift of its axial rotation vector, leading to CMB mass redistributions.
  • Mass redistributions in the mantle.

The orientation of the rotational axis itself could be changed by high-velocity impact of a massive asteroid or comet.

Rapid Pole Shift

There is the belief that the Earth will actually tilt on its axis, as stated in the readings of Edgar Cayce and numerous other psychics. Rather like the skin of an orange sliding round the fruit inside, the crust of the Earth is predicted to move accordingly. There is some evidence to support this: For example, the poles, over time, may make the planet "top heavy" with the accumulation of ice and thus, in conjunction with the natural wobble in the rotation of the Earth, combine with this to tip the axis over. Perhaps this would explain the Mammoths found in Siberia with frozen daisies in their mouths, plants that only grow in temperate climates. There are numerous legends from indigenous peoples around the world that tell of a time when either the sun stood still or 3 days of darkness (depending on which part of the planet they were on at the time) pointing towards the possibility this has happened before. Is it happening again?