On the Possibility of Instantaneous Shifts of the Poles (cont.)
By Flavio Barbiero
Phenomena which happen during a shift of the poles
Suppose the Earth has been hit by an asteroid and that the conditions to trigger a shift of the poles have been met. On the basis of the adjustments necessary to re-shape the equatorial bulge around the new axis of rotation, and the consequent re-establishment of the isostatic equilibrium of the crust, we can predict what kind of phenomena would happen on the surface.
Some areas of the Earth's crust would be driven to move upward, others downward. The up and down movements necessary to re-shape the bulge would be different from site to site. For a shift of 20o, for example, the movements would be of 7 or 8 hundred meters at the most. Very small, compared to the diameter of the Earth, but nonetheless of great consequence on the surface. We know that the mechanisms which maintain the isostatic equilibrium of the mantle are very effective; so there is no doubt that after a while the equilibrium would be re-established around the new axis of rotation, with poles and equator in different positions.
It is important to evaluate how long it would take for this to happen. We know that the layers of the crust, when subjected to a force over a certain limit, break suddenly, causing an earthquake. In the situation we have hypothesised, at the beginning only sea water would be displaced, with a gradual increase of the speed of rotation around the new axis. When the rotational speed reaches a certain critical value, sudden adjustments of the mantle would begin to happen and from that moment the process would be sharply accelerated and the reshaping of the bulge would be completed in a very short time.
How short? Weeks, days or hours? Impossible to say. A simulation with a mathematical model should give reliable results. The process of reshaping the equatorial bulge should follow a course of exponential type: after the initial sharp peak, it should decrease very quickly. Adjustment phenomena, however, are expected to continue for a long time, as the isostatic equilibrium is re-established more and more accurately.
Obviously, readjustments of that size of the equatorial bulge cannot happen without causing extensive fractures of the crust, which would provoke earthquakes of tremendous magnitude predictably stronger than the most devastating known today. A sudden burst of volcanic activity in all areas subjected to strain is also expected.
The beginning of adjustments of the crust would start not only earthquakes and volcanic activity. On the whole the oceans' water and the atmosphere follow the rotational movement of the Earth, but they are not tied to it. If the Earth should suddenly change the direction of its rotation, they would, at first, thanks to their inertia, keep up their previous motion, thus provoking a dreadful hurricane all over the continents, with violent winds and torrential rains. The continents would be swept by hurricane force winds, reaching speeds of hundreds of kilometres per hour. Only after a while the attrition with the Earth's surface would force them to follow the new movement.
The water of the oceans would play a much greater destructive role. We must expect wide fluctuation of sea level in many parts of the world, predictably in the order of hundreds of meters.
The same reasoning applies where the centre of Earth is concerned, consisting of a solid core, surrounded by a liquid layer of iron. This would at first continue in its motion, naturally undergoing strong attrition in the mantle boundary region, that would create turbulence which might have important effects. According to the latest theories, the liquid iron layer is the site of electrical currents, that are responsible for the earth's magnetic field. This turbulence could provoke perturbation in the magnetic field that might lead even to an inversion of the magnetic poles.
An important element in order to evaluate the climatic conditions following a shift of the poles, is the inclination (tilt) that the new axis of rotation will assume with respect to the ecliptic. This has a tremendous effect on the climate. According to the mechanism we have spelt out so far the axis of rotation that the Earth would acquire at the moment of impact should depend on the direction of the hit. However it is impossible to predict which would be the actual direction of the new axis once stabilised. It is certain that it would not be the same as the previous one, except for a fortuitous chance. Therefore, following a shift of the poles the course of the seasons would very likely be different.
For example, on the hypothesis that the axis of rotation is almost vertical with respect to the ecliptic, there would be an enormous growth of ice at high latitudes and altitudes, with subsequent lowering of sea level. On the other hand the climate would be much more stable then it is today, with very limited (or non-existent) seasonal climatic differences and an uninterrupted growth of vegetation. This would bring about the disruption of today's climatic barriers, with subsequent spreading of tropical species towards northern regions and vice-versa. There would also be the maximum possible development of ecological communities.
This appears to be the situation that existed in the Pleistocene era, when imposing zoological communities thrived at the very edge of the ice caps. And the phenomena which put an end to this situation appear to be the same we have described.
The 10th millennium B.C. appears to be critical under several aspects. It was precisely in that period that the Palaeolithic cultures, which had thrived for more then 30 millennia, all of a sudden disappeared. And all over the world, both in land and at sea, most of a megafauna that thrived for more than 100.000 years declined to extinction.
A geological era, the Pleistocene, came to an end, marked by a burst of volcanism, terrible earthquakes, witnessed by the collapse of the vaults in many European and American caves, and a dreadful hurricane all over the world. Even the magnetic field underwent serious challenges and nearly inverted. Not to speak about the climate which from then on went through a radical change.
12,000 years have elapsed since then, a period that is only twice the length of the historical period. We are the direct descendants of men who managed to survive those cataclysms. Is it possible that the memory of events of that kind has been completely cancelled in such a relatively short time? Myths and legends about an apocalyptic disaster, which marked the "beginning" of humankind - the "universal flood" - are common to almost all populations of the world. Some of those legends, starting from Plato's, report not only the same kind of phenomena we have described, but even the same date.
Is this only a mere coincidence or are they referring to the phenomena that put an end to the Pleistocene era only 12 thousand years ago? If we consider that a tiny asteroid can provoke an almost instantaneous shift of the poles, the second alternative looks definitely the most likely.