Mystery of the great glaciations

Our planet Earth keeps a lot of mysteries and secrets awaiting their Columbus. One of them is the mystery of the great glaciations that took place in the history of our planet. For some reason, in the polar regions and on the tops of high mountains, huge masses of ice began to accumulate, moving, crushing rocks and mountains in their path, crushing the hardest rocks.

Our planet Earth keeps a lot of mysteries and secrets awaiting their Columbus. One of them is the mystery of the great glaciations that took place in the history of our planet

The great glaciation of the Earth began about 500 thousand years ago and lasted for many millennia. The ice then retreated, then again approached. In Europe there were, apparently, four glacial epochs, between which relatively warm periods took place. The complete retreat of the ice occurred only about 20-25 thousand years ago. But in some areas of the North the ice lingered even longer. According to modern scientific data, solid masses of ice covered one fifth of the earth's surface. Under a thick layer of ice was the whole of Northern Europe up to Northern France and central Germany. East of the glacier descended the Dnieper and Don. The ice covered North America to about 380 north latitude. Modern glaciers can not go to any comparison with the ancient great glaciation of our planet. They occupy 1/30 of the earth's surface. Thus, the great glaciation was a truly planetary phenomenon.

Some researchers have tried to link the riddle of the great glaciations with cosmic processes. For example, it was suggested that in the region of the solar orbit there is a small transparent nebula into which the Sun could plunge while moving around the galactic center. This led to a decrease in the amount of solar heat entering the Earth, and caused a decrease in temperature. However, astronomical observations did not confirm this hypothesis.

Other scientists have suggested that the decrease in temperature on Earth could be caused by fluctuations in thermal solar radiation. However, long-term observations of our Sun show that the magnitude of its thermal radiation remains almost constant. Other attempts to solve the riddles of the onset of the great glaciations with a change in the tilt of the Earth's axis, the distance of the Earth from the Sun, etc. are also inconclusive.

The most reasonable can be considered the hypothesis of great glaciations, which is explained by geological changes that took place on our planet. Changes in the terrestrial relief, the formation and disappearance of high mountains, changes in the directions of sea currents, as well as the strong eruptions of volcanoes with the release into the atmosphere of a huge amount of volcanic dust that absorbs part of the solar heat could have a significant impact on the climate of our planet.

Significant impact on the climate of Europe and North America could have fluctuations in the intensity of the Gulf Stream, whose power is unusually large. Suffice it to say that every second it carries 26 million cubic meters of water, which is about 20 times higher than the flow of water of all rivers of the globe. The heat brought by this flow accounts for about 45% of the total heat balance of the Arctic Ocean. If the Gulf Stream ceased to exist, then a significant part of Europe would be icebound. Therefore, a natural question arises could the temporary disappearance of the Gulf Stream cause the great glaciations of Europe? But why could the Gulf Stream disappear?

It is well known that in the history of our planet more than once there have been the lowering and raising of various parts of the earth's crust. The study of the ocean depths showed that at the bottom of them there are many submerged mountain ranges. These include the North Atlantic Ridge in the Atlantic Ocean. Currently, all these ridges continue to dive. It is possible that in ancient times in their place there were continents, now descended to the bottom of the ocean.

In particular, some very interesting information was found indicating that the North Atlantic ridge did once rise above the surface of the ocean. But if the disappearance of the North Atlantic Ridge in the depths of the ocean really took place, when was it? It was established that about 35 thousand years ago there was a noticeable increase in the Gulf Stream. In addition, it was discovered that another breakthrough of the warm waters of the Gulf Stream into the Kara Sea occurred about 1012 thousand years ago. This period coincides with the estimated date of immersion of the North Atlantic Ridge.

Many scientists connect the riddle of the great glaciations of the Earth with these events. Land areas appearing from the seabed in the Atlantic Ocean blocked the path to the north to warm sea currents. As a result, a strong cooling began in the polar regions, and powerful ice cover was approaching the territory of Europe and North America. When the land sank to the bottom of the ocean, the Gulf Stream again got free access to the northern areas. The released current carried warmth to the ice-bound shores and the ice receded!

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