What happens if there is an ice age. Interesting facts about the ice age. Are we standing on the edge of the end of the world

Although it may be difficult to understand, our planet is constantly changing. Continents are constantly shifting and colliding with each other. Volcanoes erupt, glaciers expand and retreat, and life must keep pace with all of these changes that are taking place.

Throughout its existence, in different periods that lasted millions of years, the Earth was covered with a kilometer-long polar ice sheet and mountain glaciers. The subject of this list will be ice ages, characterized by very cold climates and ice that extends as far as the eye can see.

What is an ice age?
Believe it or not, the definition of an ice age is not as straightforward as some might think. Of course, we can characterize it as a period when global temperatures were much colder than they are today, and when both hemispheres were covered in a sheet of ice that stretched thousands of miles to the equator.

However, the problem with this definition is that it describes any ice age from today's point of view and does not, in fact, take into account the entire planetary history. Who can say that today we do not live in conditions of lower than average temperatures? In this case, we are actually in an ice age right now. Only a few scientists who have devoted their lives to the study of such phenomena can confirm this. Yes, we are indeed living in an ice age, and we will see this in a minute.

A better definition of an ice age would be that it is a long period of time when the planet's atmosphere and surface are cold, leading to the presence of polar ice sheets and mountain glaciers. This can last for several million years, during which there are also periods of glaciation, characterized by ice cover and the growth of glaciers on the surface of the planet, as well as interglacial periods - intervals lasting several thousand years, when the ice retreats and becomes warmer. In other words, what we know as the "last ice age" is, in fact, one such glacial stage, part of the larger Pleistocene ice age, and we are currently in an interglacial period known as the Holocene, which began around 11,700 years ago.

What causes an ice age?
At first glance, the ice age looks like some kind of global warming in reverse. This is true to a certain extent, but there are several other factors that can initiate and contribute to the beginning of the ice age. It is important to note that the study of ice ages began not so long ago, and our understanding of this process is not yet complete. However, there is some scientific consensus on several factors that contribute to the onset of the Ice Age.

One such obvious factor is the level of greenhouse gases in the atmosphere. There is evidence that the concentration of these gases in the air rises and falls along with the retreat and growth of ice sheets. But some argue that these gases do not necessarily set off every ice age and only affect its severity.

Another key factor that plays an important role is the tectonic plates. Geological records indicate a correlation between the position of the continents and the onset of the Ice Age. This means that in a certain position, the continents can interfere with the so-called Global Ocean Conveyor - a global system of currents that carry cold water from the poles to the equator and vice versa.

Continents can also be right on top of the pole, like Antarctica is today, or cause polar waters to be completely or partially surrounded by land, like the Arctic Ocean. Both of these factors contribute to ice formation. Continents can also gather around the equator, blocking ocean currents, leading to an ice age.

This is exactly what happened during the Cryogenic period, when the supercontinent Rodinia covered most of the equator. Some experts even say that the Himalayas played an important role in the current ice age. After these mountains began to form about 70 million years ago, they contributed to the increase in precipitation on the planet, which in turn led to a steady decrease in CO2 in the air.

Finally, we have the orbits in which the Earth moves. It also partially explains the periods of glaciation and interglacial periods during any particular ice age. The Earth experiences a series of periodic changes during its circular motion around the Sun, which are called Milankovitch Cycles. The first of these cycles is the Earth's eccentricity, which is characterized by the shape of our planet's orbit around the Sun.

Every 100,000 years or so, the Earth's orbit becomes more or less elliptical, which means it will receive more or less sunlight. The second of these cycles is the tilt of the planet's axis, which on average changes by a few degrees every 41,000 years. This tilt affects the seasons on Earth and the difference in solar radiation received by the poles and the equator. Thirdly, we have the Earth's precession, which is expressed as a wobble as the Earth rotates on its axis. This happens about every 23,000 years and results in Northern Hemisphere winter when the Earth is farthest from the Sun and summer when it is closest to the Sun. If this happens, the difference in severity between seasons will be greater than today. In addition to these major factors, we can also sometimes suffer from a lack of sunspots, large meteorite impacts, massive volcanic eruptions, or nuclear wars that could potentially start an ice age, among other things.

Why do they go on for so long?
We know that ice ages usually last millions of years. The reason for this can be explained by a phenomenon known as albedo. This is the reflectivity of the Earth's surface when it comes to shortwave radiation from the Sun. In other words, the more of our planet's surface covered in white ice and snow, the more solar radiation is reflected back into space, and the colder it gets on Earth. This results in even more ice and even more reflectivity in a positive feedback loop that lasts millions of years. This is one of the reasons why it is so important that the Greenland ice stays where it is. Because if it doesn't, the reflectivity of the island will decrease, leading to an increase in global temperature.

However, the ice ages eventually end, and so do their glacial periods. As the air gets colder, it can no longer hold as much moisture as it used to, which in turn results in less snowfall and an inability to expand or even maintain ice caps. As a result, a cycle of negative feedback begins, which marks the beginning of the interglacial period.

By this logic, a theory was proposed in 1956 suggesting that the Arctic Ocean, which was not covered by ice, would cause more snowfall at higher latitudes, above and below the Arctic Circle. This snow can be so abundant that it does not melt during the summer months, increasing the Earth's albedo and decreasing the overall temperature. Over time, this will allow ice to form at lower latitudes and mid-latitudes, a push that starts the glaciation process.

But how do we know that the ice age really was?
The reason people started thinking about ice ages was, in the first place, some huge boulders that ended up in the middle of an empty area with no explanation as to how they got there. The study of glaciation began in the mid-18th century, when the Swiss engineer and geographer Pierre Martel began to document the chaotically scattered mountain formations within the Alpine valley and below the glacier. The locals told him that these huge boulders were pushed by a glacier that once extended much further up the mountain.

Over the decades, other similar cases were documented around the world, which became the basis for the theory of ice ages. Since then, other forms of evidence have been taken into account. Geological features, including previously mentioned rocks containing glacial deposits, carved valleys such as fjords, glacial lakes, and various other forms of rugged land surface. The problem with them is that they are difficult to date, and subsequent glaciations can distort or even completely erase previous geological formations.

More accurate data comes from paleontology - the study of fossils. Although not without some shortcomings and inaccuracies, paleontology speaks of the history of ice ages, showing us the distribution of cold-adapted organisms that once lived at lower latitudes, and organisms that normally thrive in warmer climates, which either declined closer to the equator, or they completely disappeared.

However, the most accurate evidence comes from isotopes. Differences in isotope ratios between fossils, sediments, and ocean sediments can tell a lot about the environment in which they formed. Speaking of the current ice age, we also have access to ice cores from Antarctica and Greenland, which are the most reliable form of evidence to date. When formulating their theories and predictions, scientists rely on a combination of them where possible.

Great Ice Ages
At the moment, scientists are confident that during the long history of the Earth there were five major ice ages. The first of these, known as the Huronian glaciation, occurred about 2.4 billion years ago and lasted about 300 million years, is considered the longest. The Cryogenic Ice Age occurred about 720 million years ago and continued until 630 million years ago. This period is considered the most severe. The third massive glaciation occurred about 450 million years ago and lasted about 30 million years. It is known as the Ando-Saharan Ice Age and caused the second largest mass extinction in Earth's history after the so-called Great Dying. Lasting for 100 million years, the Karoo Ice Age occurred between 360 and 260 million years ago and was triggered by the appearance of land plants, the remains of which we now use as fossil fuels.

Finally, we have the Pleistocene Ice Age, also known as the Pliocene-Quaternary glaciation. It began approximately 2.58 million years ago, and since then there have been several periods of glaciation and interglacial periods with a difference of approximately 40,000 to 100,000 years. However, over the past 250,000 years, the climate has changed more frequently and dramatically, with the previous interglacial interrupted by numerous cold spells lasting several centuries. The current interglacial period, which began approximately 11,000 years ago, is atypical due to the relatively stable climate that has existed up to that point. It is safe to say that people would not have been able to farm and reach the current level of civilization, if not for this unusual period of temperature stability.

Witchcraft
"I'm sorry, what?" We know what you thought when you saw this title on our list. But now we'll explain everything...

For several centuries, beginning around 1300 and ending around 1850, the world experienced a period known as the Little Ice Age. For global temperatures to drop, especially in the Northern Hemisphere, causing mountain glaciers to grow, rivers to freeze, and crops to die, several factors were required. In the middle of the 17th century in Switzerland, several villages were completely destroyed due to invading glaciers, and in 1622 even the southern part of the Bosphorus around Istanbul completely froze. Things got worse in 1645 and continued to do so for the next 75 years, during a period known to scientists today as the Maunder Low.

During this time, there were few sunspots on the sun. These spots are areas on the surface of the Sun where temperatures are much cooler. They are caused by the concentration of magnetic fluxes in our star. On their own, these patches are likely to help cool the Earth's temperature, but they are surrounded by very bright regions known as faculae. The faculae have a much higher radiation power, which far exceeds the weakness of the glow caused by sunspots. Thus, a sun without spots actually has a lower level of radiation than usual. During the 17th century, it is estimated that the Sun dimmed by 0.2 percent, which partly explains this Little Ice Age. During this time, more than 17 volcanic eruptions occurred in the world, which further weakened the sun's rays.

The economic hardships caused by this centuries-old cold period had an incredible psychological impact on people. Frequent crop losses and firewood shortages led to serious cases of mass hysteria erupting in Salem, Massachusetts. In the winter of 1692, twenty people, fourteen of whom were women, were hanged on charges of being witches and responsible for all the misfortunes of the rest. Five others, two of whom were children, later died in prison, where they were placed on the same charge. Due to adverse weather in places like Africa, even today people sometimes accuse each other of being witches.

Earth is a snowball
The first ice age on Earth was also the longest. As we mentioned earlier, it lasted as much as 300 million years. Known as the Huronian glaciation, this incredibly long and cold period began about 2.4 billion years ago, at a time when only single-celled organisms existed on Earth. The landscape looked very different than it does today, even before the ice covered everything around. However, a series of events took place that eventually led to an apocalyptic event of global proportions, as a result of which most of the planet was covered in thick ice. Before the Huronian glaciation, anaerobic organisms that did not need oxygen predominated on Earth. Oxygen was, in fact, poisonous to them and an extremely rare element in the air, it only made up 0.02% of the atmosphere. But at some point, another form of life arose - cyanobacteria.

This tiny bacterium was the first to ever use photosynthesis as a way of feeding. The by-product of this process is oxygen. As these tiny creatures thrived in the oceans, they released millions and millions of tons of oxygen, raising its concentration in the atmosphere to 21% and causing the extinction of all anaerobic life. This event is called the Great Oxygen Event. The air was also filled with methane, and in contact with oxygen, it turned into CO2 and water. However, methane is 25 times more efficient as a greenhouse gas than CO2, which means that this transformation caused global temperatures to drop, which in turn triggered the Huronian glaciation and the first mass extinction on Earth. Sometimes volcanoes added extra CO2 to the air, leading to interglacial periods.

Baked Alaska
If its name isn't clear enough, the Cryogenic Ice Age was the coldest period in Earth's long history. Today it is also the subject of many scientific disputes. One of the topics of discussion is the question of whether the Earth was completely covered in ice, or whether there was a line of open water along the equator - the Snowball or Snowball Earth theory, as some call these two scenarios. The cryogenic period lasted from about 720 to 635 million years ago and can be divided into two major glaciation events known as the Startan (720-680 million years) and Marinoan (approximately 650 to 635 million years). It is important to note that multicellular life did not exist at this point, and some believe that the Snowball Earth scenario catalyzed its evolution during the so-called Cambrian Explosion.

A particularly interesting study was published back in 2009, focusing in particular on the Marinoan glaciation. According to the analysis, the Earth's atmosphere was relatively warm and its surface was covered with a thick layer of ice. This is possible only if the planet is completely or almost completely covered in ice. This phenomenon has been compared to Baked Alaska, where the ice cream does not melt immediately after being placed in the oven. It turns out that there were a lot of greenhouse gases in the composition of the atmosphere, but contrary to expectations, this did not prevent and was in no way connected with the ice age. These gases were present in such large quantities due to the increased volcanic activity that followed the breakup of the Rodinia supercontinent. This prolonged volcanic activity is believed to have helped kickstart the Ice Age.

However, the scientific community warns that something similar could happen again if the atmosphere reflects too much of the sun's rays into space. One such period could be triggered by a massive volcanic eruption, a nuclear war, or our future attempts to mitigate the effects of global warming by spraying too much sulfate aerosols into the atmosphere.

Flood myths
When the glacial ice began to melt about 14,500 years ago, water did not flow into the ocean in the same way across the Earth. In some places, such as North America, huge glacial lakes have begun to form. These lakes appear as a result of an obstacle in the way of water in the form of an ice wall or glacial deposits. In 1600 years, Lake Agassiz covered an area of ​​440,000 sq. km - more than any lake that exists today. It was formed in North Dakota, Minnesota, Manitoba, Saskatchewan and Ontario. When the dam finally broke, fresh water poured into the Arctic Ocean through the Mackenzie River valley.

This large influx of fresh water weakened the ocean current by 30%, plunging the planet into a 1,200-year ice age known as the Early Dryas. It is assumed that this unfortunate turn of events led to the destruction of the Clovis culture and the North American megafauna. Records also show that this cold period ended abruptly around 11,500 years ago, with temperatures in Greenland rising to -7 degrees Celsius in just ten years.

During the Early Dryas, the ice of the glaciers replenished, and when the planet began to warm up again, Lake Agassiz appeared. However, this time it connected with an equally large lake known as Ojibway. Shortly after their merger, another breakthrough occurred, but this time into Hudson Bay. Another cold period that occurred 8,200 years ago is known as the 8.2 kiloyear event.

Although low temperatures lasted only 150 years, this event allowed sea levels to rise by 4 meters. Interestingly, historians have been able to link the origins of many flood myths around the world to this time period. This sudden rise in sea levels also caused the Mediterranean to carve its way through the Bosphorus and flood the Black Sea, which at the time was only a freshwater lake.

martian ice age
Ice ages beyond our control are natural phenomena that happen not only on Earth. Like our planet, Mars also experiences periodic changes in orbit and axial tilt. But unlike Earth, where an ice age means the growth of polar ice caps, Mars is experiencing a different process. Since its axis is tilted more than Earth's and the poles receive more sunlight, the Martian Ice Age means that the polar ice caps are actually retreating and the mid-latitude glaciers are expanding. This process stops during interglacial periods.

Over the past 370,000 years, Mars has been slowly emerging from its ice age and entering an interglacial period. Scientists estimate that approximately 87,115 cubic kilometers of ice accumulates at the poles, most of which accumulates in the Northern Hemisphere. Computer models have also shown that Mars can become completely covered in ice during a glaciation. However, these studies are in their early stages, and given the fact that we are still far from fully understanding Earth's own ice ages, we cannot expect to know everything that happens on Mars. However, this study may prove useful given our future plans for the Red Planet. It also helps us a lot on Earth. "Mars serves as a simplistic laboratory for testing climate models and scenarios, without the oceans and biology, which we can then use to better understand Earth systems," said planetary scientist Isaac Smith.

Prior to this, scientists for decades predicted the imminent onset of global warming on Earth, due to industrial human activity, and assured that "there would be no winter." Today, the situation seems to have changed dramatically. Some scientists believe that a new ice age is beginning on Earth.

This sensational theory belongs to an oceanologist from Japan - Mototake Nakamura. According to him, starting from 2015, the Earth will begin to cool. His point of view is also supported by a Russian scientist, Khababullo Abdusammatov from the Pulkovo Observatory. Recall that the last decade was the warmest for the entire time of meteorological observations, i.e. since 1850.

Scientists believe that already in 2015 there will be a decrease in solar activity, which will lead to climate change and its cooling. The temperature of the ocean will decrease, the amount of ice will increase, and the overall temperature will drop significantly.

Cooling will reach its maximum in 2055. From this moment, a new ice age will begin, which will last 2 centuries. Scientists have not specified how severe the icing will be.

There is a positive point in all this, it seems that polar bears are no longer threatened with extinction)

Let's try to figure it all out.

1 Ice Ages can last hundreds of millions of years. The climate at this time is colder, continental glaciers are formed.

For example:

Paleozoic Ice Age - 460-230 Ma
Cenozoic Ice Age - 65 million years ago - present.

It turns out that in the period between: 230 million years ago and 65 million years ago, it was much warmer than now, and we live in the Cenozoic Ice Age today. Well, we figured out the eras.

2 The temperature during the ice age is not uniform, but also changes. Ice ages can be distinguished within an ice age.

glacial period(from Wikipedia) - a periodically repeating stage in the geological history of the Earth lasting several million years, during which, against the background of a general relative cooling of the climate, repeated sharp growths of continental ice sheets - ice ages occur. These epochs, in turn, alternate with relative warmings - epochs of glaciation reduction (interglacials).

Those. we get a nesting doll, and inside the cold ice age, there are even colder segments, when the glacier covers the continents from above - ice ages.

We live in the Quaternary Ice Age. But thank God during the interglacial.

The last ice age (Vistula glaciation) began ca. 110 thousand years ago and ended around 9700-9600 BC. e. And this is not so long ago! 26-20 thousand years ago, the volume of ice was at its maximum. Therefore, in principle, there will definitely be another glaciation, the only question is when exactly.

Map of the Earth 18 thousand years ago. As you can see, the glacier covered Scandinavia, Great Britain and Canada. Note also the fact that the level of the ocean has dropped and many parts of the earth's surface have risen out of the water, now under water.

The same card, only for Russia.

Perhaps the scientists are right, and we will be able to observe with our own eyes how new lands protrude from under the water, and the glacier takes the northern territories for itself.

Come to think of it, the weather has been pretty stormy lately. Snow fell in Egypt, Libya, Syria and Israel for the first time in 120 years. There was even snow in tropical Vietnam. In the USA for the first time in 100 years, and the temperature dropped to a record -50 degrees Celsius. And all this against the backdrop of positive temperatures in Moscow.

The main thing is to prepare well for the ice age. Buy a site in the southern latitudes, away from big cities (there are always full of hungry people during natural disasters). Make an underground bunker there with food supplies for years, buy weapons for self-defense and prepare for life in the style of Survival horror))

The last ice age brought about the appearance of the woolly mammoth and a huge increase in the area of ​​glaciers. But it was only one of many that have cooled the Earth throughout its 4.5 billion years of history.

So, how often does the planet go through ice ages, and when should we expect the next one?

The main periods of glaciation in the history of the planet

The answer to the first question depends on whether you mean the big glaciations or the small ones that occur during these long periods. Throughout history, the Earth has experienced five major glaciations, some of them lasting hundreds of millions of years. In fact, even now, the Earth is going through a large period of glaciation, and this explains why it has polar ice.

The five main ice ages are the Huronian (2.4–2.1 billion years ago), the Cryogenian glaciation (720–635 million years ago), the Andean-Saharan (450–420 million years ago), and the late Paleozoic glaciation (335–260 million years ago) and Quaternary (2.7 million years ago to present).

These major periods of glaciation may alternate between smaller ice ages and warm periods (interglacials). At the beginning of the Quaternary glaciation (2.7-1 million years ago), these cold ice ages occurred every 41,000 years. However, in the last 800,000 years, significant ice ages have occurred less frequently, about every 100,000 years.

How does the 100,000 year cycle work?

Ice sheets grow for about 90,000 years and then begin to melt during the 10,000 year warm period. Then the process is repeated.

Given that the last ice age ended about 11,700 years ago, perhaps it's time for another one to begin?

Scientists believe that we should be experiencing another ice age right now. However, there are two factors associated with the Earth's orbit that influence the formation of warm and cold periods. Considering how much carbon dioxide we emit into the atmosphere, the next ice age won't start for at least another 100,000 years.

What causes an ice age?

The hypothesis put forward by the Serbian astronomer Milyutin Milanković explains why there are cycles of ice and interglacial periods on Earth.

As the planet revolves around the Sun, the amount of light it receives from it is affected by three factors: its inclination (which ranges from 24.5 to 22.1 degrees in a cycle of 41,000 years), its eccentricity (changing the shape of the orbit around of the Sun, which fluctuates from a near circle to an oval shape) and its wobble (one complete wobble occurs every 19-23 thousand years).

In 1976, a landmark paper in the journal Science presented evidence that these three orbital parameters explained the planet's glacial cycles.

Milankovitch's theory is that orbital cycles are predictable and very consistent in a planet's history. If the Earth is going through an ice age, then it will be covered in more or less ice, depending on these orbital cycles. But if the Earth is too warm, no change will occur, at least in regards to the growing amount of ice.

What can affect the warming of the planet?

The first gas that comes to mind is carbon dioxide. Over the past 800,000 years, carbon dioxide levels have fluctuated between 170 and 280 parts per million (meaning that out of 1 million air molecules, 280 are carbon dioxide molecules). A seemingly insignificant difference of 100 parts per million leads to the appearance of glacial and interglacial periods. But carbon dioxide levels are much higher today than they were in past fluctuations. In May 2016, carbon dioxide levels over Antarctica reached 400 parts per million.

The earth has warmed up so much before. For example, during the time of the dinosaurs, the air temperature was even higher than now. But the problem is that in the modern world it is growing at a record pace, because we have released too much carbon dioxide into the atmosphere in a short time. In addition, given that emission rates are not declining to date, it can be concluded that the situation is unlikely to change in the near future.

The consequences of warming

The warming caused by the presence of this carbon dioxide will have big consequences, because even a small increase in the average temperature of the Earth can lead to drastic changes. For example, the Earth was on average only 5 degrees Celsius colder during the last ice age than it is today, but this has led to a significant change in regional temperature, the disappearance of a huge part of the flora and fauna, and the appearance of new species.

If global warming causes all of the ice sheets in Greenland and Antarctica to melt, ocean levels will rise by 60 meters compared to today.

What causes great ice ages?

The factors that caused long periods of glaciation, such as the Quaternary, are not as well understood by scientists. But one idea is that a massive drop in carbon dioxide levels could lead to cooler temperatures.

So, for example, according to the uplift and weathering hypothesis, when plate tectonics leads to the growth of mountain ranges, new unprotected rock appears on the surface. It is easily weathered and disintegrates when it enters the oceans. Marine organisms use these rocks to create their shells. Over time, stones and shells take carbon dioxide from the atmosphere and its level drops significantly, which leads to a period of glaciation.

last ice age

During this era, 35% of the land was under the ice cover (compared to 10% at present).

The last ice age was not just a natural disaster. It is impossible to understand the life of planet Earth without considering these periods. In the intervals between them (known as interglacial periods), life flourished, but then once again the ice inexorably approached and brought death, but life did not completely disappear. Each ice age was marked by the struggle for the survival of different species, global climate changes occurred, and in the last of them a new species appeared, which became (over time) dominant on Earth: it was man.
ice ages
Ice ages are geological periods characterized by a strong cooling of the Earth, during which vast expanses of the earth's surface were covered with ice, a high level of humidity was observed and, of course, exceptional cold, as well as the lowest sea level known to modern science. There is no generally accepted theory regarding the causes of the onset of the ice age, however, since the 17th century, various explanations have been proposed. According to current opinion, this phenomenon was not caused by one cause, but was the result of the influence of three factors.

Changes in the composition of the atmosphere - a different ratio of carbon dioxide (carbon dioxide) and methane - caused a sharp drop in temperature. This is similar to what we now call global warming, but on a much larger scale.

The movements of the continents, caused by cyclical changes in the orbit of the Earth around the Sun, and in addition, a change in the angle of inclination of the planet's axis relative to the Sun, also had an impact.

The earth received less solar heat, it cooled, which led to glaciation.
The earth has experienced several ice ages. The largest glaciation occurred 950-600 million years ago in the Precambrian era. Then in the Miocene epoch - 15 million years ago.

The traces of glaciation that can be observed at the present time represent the legacy of the last two million years and belong to the Quaternary period. This period is best studied by scientists and is divided into four periods: Günz, Mindel (Mindel), Ries (Rise) and Würm. The latter corresponds to the last ice age.

last ice age
The Wurm stage of glaciation began approximately 100,000 years ago, reached its maximum after 18 thousand years, and began to decline after 8 thousand years. During this time, the thickness of the ice reached 350-400 km and covered a third of the land above sea level, in other words, three times more space than now. Based on the amount of ice that currently covers the planet, one can get some idea of ​​the area of ​​glaciation during that period: today glaciers occupy 14.8 million km2, or about 10% of the earth's surface, and during the ice age they covered an area of ​​44 .4 million km2, which is 30% of the Earth's surface.

Northern Canada was estimated to have covered 13.3 million km2 of ice, while 147.25 km2 is now under ice. The same difference is observed in Scandinavia: 6.7 million km2 in that period compared to 3910 km2 today.

The ice age began simultaneously in both hemispheres, although in the North the ice spread to more extensive areas. In Europe, the glacier captured most of the British Isles, northern Germany and Poland, and in North America, where the Wurm glaciation is called the "Wisconsin glacial stage", a layer of ice that descended from the North Pole covered all of Canada and spread south of the Great Lakes. Like the lakes in Patagonia and the Alps, they were formed on the site of recesses left after the melting of the ice mass.

The sea level dropped by almost 120 m, as a result of which large expanses that are currently covered with sea water were exposed. The significance of this fact is enormous, since large-scale human and animal migrations became possible: hominids were able to make the transition from Siberia to Alaska and move from continental Europe to England. It is possible that during the interglacial periods, the two largest ice massifs on Earth - Antarctica and Greenland - have undergone little change over the course of history.

At the peak of glaciation, the indicators of the average temperature drop varied significantly depending on the locality: 100 ° C - in Alaska, 60 ° C - in England, 20 ° C - in the tropics and remained practically unchanged at the equator. Conducted studies of the last glaciations in North America and Europe, which occurred during the Pleistocene era, gave the same results in this geological region within the last two (approximately) million years.

The last 100,000 years are of particular importance for understanding the evolution of mankind. Ice ages have become a severe test for the inhabitants of the Earth. After the end of the next glaciation, they again had to adapt, learn to survive. When the climate became warmer, the sea level rose, new forests and plants appeared, the land rose, freed from the pressure of the ice shell.

The hominids turned out to have the most natural data to adapt to the changed conditions. They were able to move to areas with the most food resources, where the slow process of their evolution began.
Not expensive to buy children's shoes in bulk in Moscow

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1.8 million years ago began the Quaternary (anthropogenic) period of the geological history of the earth, which continues to this day.

River basins expanded. There was a rapid development of the fauna of mammals, especially mastodons (which would later become extinct, like many other ancient animal species), ungulates and higher monkeys. In this geological period of the history of the earth, a person appears (hence the word anthropogenic in the name of this geological period).

The Quaternary period is marked by a sharp change in climate throughout the European part of Russia. From a warm and humid Mediterranean, it turned into a temperate cold, and then into a cold Arctic one. This led to glaciation. Ice accumulated on the Scandinavian Peninsula, in Finland, on the Kola Peninsula and spread to the south.

The Oksky glacier, with its southern edge, also covered the territory of the modern Kashirsky region, including our region. The first glaciation was the coldest; woody vegetation in the Oka region disappeared almost completely. The glacier did not last long. The first Quaternary glaciation reached the Oka valley, which is why it received the name “Oksky glaciation”. The glacier left moraine deposits dominated by boulders of local sedimentary rocks.

But such favorable conditions were again replaced by a glacier. The glaciation was on a planetary scale. The grandiose Dnieper glaciation began. The thickness of the Scandinavian ice sheet reached 4 kilometers. The glacier moved across the Baltic to Western Europe and the European part of Russia. The boundaries of the languages ​​of the Dnieper glaciation passed in the area of ​​modern Dnepropetrovsk and almost reached Volgograd.

mammoth fauna

The climate warmed up again and became Mediterranean. In place of the glaciers, heat-loving and moisture-loving vegetation spread: oak, beech, hornbeam and yew, as well as linden, alder, birch, spruce and pine, hazel. In the marshes grew ferns, characteristic of modern South America. The restructuring of the river system and the formation of Quaternary terraces in the river valleys began. This period was called the interglacial Oxo-Dnieper age.

The Oka served as a kind of barrier to the advancement of ice fields. According to scientists, the right bank of the Oka, i.e. our region has not turned into a continuous icy desert. Here were fields of ice, interspersed with intervals of melted hills, between which rivers flowed from melt water and lakes accumulated.

Ice flows of the Dnieper glaciation brought glacial boulders from Finland and Karelia to our region.

The valleys of the old rivers were filled with mid-moraine and fluvioglacial deposits. It warmed up again, and the glacier began to melt. Streams of melt water rushed south along the channels of new rivers. During this period, the third terraces are formed in the river valleys. Large lakes formed in the depressions. The climate was moderately cold.

In our region, forest-steppe vegetation dominated with a predominance of coniferous and birch forests and large areas of steppes covered with wormwood, quinoa, grasses and herbs.

The interstadial epoch was short. The glacier returned to the Moscow region again, but did not reach the Oka, stopping not far from the southern outskirts of modern Moscow. Therefore, this third glaciation was called Moscow. Some tongues of the glacier reached the Oka valley, but they did not reach the territory of the modern Kashirsky region. The climate was severe, and the landscape of our region becomes close to the steppe tundra. Forests are almost disappearing and their place is taken by steppes.

A new warming has come. The rivers deepened their valleys again. The second terraces of the rivers were formed, the hydrography of the Moscow region changed. It was during that period that the modern valley and basin of the Volga, which flows into the Caspian Sea, was formed. The Oka, and with it our river B. Smedva and its tributaries, entered the Volga river basin.

This interglacial period in terms of climate went through stages from continentally temperate (close to modern) to warm, with a Mediterranean climate. In our region, birch, pine and spruce dominated at first, and then heat-loving oaks, beeches and hornbeams turned green again. In the swamps, the water lily grew, which today you will find only in Laos, Cambodia or Vietnam. At the end of the interglacial period, birch-coniferous forests again dominated.

This idyll was spoiled by the Valdai glaciation. Ice from the Scandinavian Peninsula again rushed to the south. This time the glacier did not reach the Moscow region, but changed our climate to subarctic. For many hundreds of kilometers, including the territory of the present Kashirsky district and the rural settlement of Znamenskoye, the steppe-tundra stretches, with dried grass and rare shrubs, dwarf birches and polar willows. These conditions were ideal for the mammoth fauna and for primitive man, who then already lived on the borders of the glacier.

During the last Valdai glaciation, the first river terraces formed. The hydrography of our region has finally taken shape.

Traces of glacial epochs are often found in the Kashirsky region, but they are difficult to identify. Of course, large stone boulders are traces of the glacial activity of the Dnieper glaciation. They were brought by ice from Scandinavia, Finland and from the Kola Peninsula. The most ancient traces of the glacier are moraine or boulder loam, which is a random mixture of clay, sand, brown stones.

The third group of glacial rocks are sands resulting from the destruction of moraine layers by water. These are sands with large pebbles and stones, and the sands are homogeneous. They can be observed on the Oka. These include the Belopesotsky sands. Often found in the valleys of rivers, streams, in ravines, layers of flint and limestone gravel are traces of the bed of ancient rivers and streams.

With new warming, the geological epoch of the Holocene began (it began 11,400 years ago), which continues to this day. The modern river floodplains were finally formed. The mammoth fauna died out, and forests appeared in place of the tundra (at first, spruce, then birch, and later mixed). The flora and fauna of our region has acquired the features of modern - the one that we see today. At the same time, the left and right banks of the Oka are still very different in their forest cover. If mixed forests and many open areas prevail on the right bank, then continuous coniferous forests dominate on the left bank - these are traces of glacial and interglacial climate changes. On our bank of the Oka, the glacier left fewer traces, and our climate was somewhat milder than on the left bank of the Oka.

Geological processes continue today. The earth's crust in the Moscow region over the past 5 thousand years has been rising only slightly, at a rate of 10 cm per century. The modern alluvium of the Oka and other rivers of our region is being formed. What this will lead to after millions of years, we can only guess, because, having briefly become acquainted with the geological history of our region, we can safely repeat the Russian proverb: "Man proposes, but God disposes." This saying is especially relevant, after we have seen in this chapter that human history is a grain of sand in the history of our planet.

GLACIAL PERIOD

In the distant, distant times, where Leningrad, Moscow, Kyiv are now, everything was different. Dense forests grew along the banks of ancient rivers, and shaggy mammoths with bent tusks, huge furry rhinoceroses, tigers and bears much larger than today roamed there.

Gradually, these places became colder and colder. Far in the north, so much snow fell every year that entire mountains of it accumulated - larger than the present Urals. The snow caked up, turned into ice, then slowly began to spread, spreading in all directions.

Ice mountains have moved over the ancient forests. Cold, evil winds blew from these mountains, trees froze and animals fled from the cold to the south. And the icy mountains crawled further south, twisting the rocks along the way and moving whole hills of earth and stones in front of them. They crawled to the place where Moscow now stands, and crawled even further, to the warm southern countries. They reached the hot Volga steppe and stopped.

Here, finally, the sun overpowered them: the glaciers began to melt. Huge rivers flowed from them. And the ice receded, melted, and the masses of stones, sand and clay that the glaciers brought, remained lying in the southern steppes.

More than once, terrible ice mountains approached from the north. Have you seen the cobblestone pavement? Such small stones are brought by the glacier. And there are boulders the size of a house. They still lie in the north.

But the ice can move again. Just not soon. Maybe thousands of years will pass. And not only the sun will then fight the ice. If necessary, people will use NUCLEAR ENERGY and keep the glacier out of our land.

When did the ice age end?

Many of us believe that the Ice Age ended a very long time ago and no traces of it remain. But geologists say we're only getting closer to the end of the Ice Age. And the inhabitants of Greenland are still living in the Ice Age.

Approximately 25 thousand years ago, the peoples who inhabited the central part of NORTH AMERICA saw ice and snow all year round. A huge wall of ice stretched from the Pacific to the Atlantic Ocean, and north to the very Pole. It was during the final stages of the Ice Age, when all of Canada, most of the United States, and northwestern Europe were covered in a layer of ice over one kilometer thick.

But this does not mean that it was always very cold. In the northern part of the United States, the temperature was only 5 degrees below present. The cold summer months triggered an ice age. At this time, the heat was not enough to melt the ice and snow. It accumulated and eventually covered the entire northern part of these areas.

The Ice Age consisted of four stages. At the beginning of each of them, ice formed moving south, then melted and retreated to the North POLE. This happened, it is believed, four times. Cold periods are called "glaciation", warm - "interglacial" period.

The first stage in North America is believed to have started about two million years ago, the second about 1,250,000 years ago, the third about 500,000 years ago, and the last about 100,000 years ago.

The rate of ice melting at the last stage of the ice age in different regions was not the same. For example, in the area of ​​present-day Wisconsin in the United States, ice melt began about 40,000 years ago. The ice that covered the New England area in the US disappeared about 28,000 years ago. And the territory of the modern state of Minnesota was freed by ice only 15,000 years ago!

In Europe, Germany was free of ice 17,000 years ago, while Sweden only 13,000 years ago.

Why do glaciers still exist today?

The huge mass of ice that began the ice age in North America was called the "continental glacier": in the very center, its thickness reached 4.5 km. It is possible that this glacier formed and melted four times during the entire ice age.

The glacier that covered other parts of the world has not melted in some places! For example, the huge island of Greenland is still covered by continental ice, except for a narrow coastal strip. In its middle part, the glacier sometimes reaches a thickness of more than three kilometers. Antarctica is also covered by a vast continental glacier up to 4 kilometers thick in some places!

So the reason why there are glaciers in some parts of the world is that they have not melted since the Ice Age. But the bulk of the glaciers that are found now, formed recently. They are mainly located in mountain valleys.

They originate in wide, gently sloping, amphitheater-like valleys. Snow falls here from the slopes as a result of landslides and avalanches. Such snow does not melt in the summer, becoming deeper every year.

Gradually, pressure from above, some thawing, and repeated freezing remove air from the bottom of this snow mass, turning it into solid ice. The impact of the weight of the entire mass of ice and snow compresses the entire mass and causes it to move down the valley. Such a moving tongue of ice is a mountain glacier.

More than 1200 such glaciers are known in Europe in the Alps! They also exist in the Pyrenees, in the Carpathians, in the Caucasus, as well as in the mountains of southern Asia. There are tens of thousands of these glaciers in southern Alaska, some 50 to 100 km long!

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The author gives an alarming forecast of the threat of a new Great glaciation of the Northern Hemisphere of the Earth in the very near future or even in the present. A new hypothesis of glacial fluctuations of the Late Cenozoic (i.e., our time, the last geological epoch) is put forward. In Northeast Asia, Alaska, and the northwestern islands of the Canadian Arctic Archipelago, they have always been associated with periods of grandiose local warming.

The main role in the alternation of glaciations and interglacials of the Cenozoic was played not by general cooling or warming of the Earth, but, first of all, by the North Atlantic Current (Gulf Stream) and the North Pacific Current (Kuroshio), as well as currents dependent on them. Changes in ocean currents occurred as a result of vertical displacements of the ocean floor, and primarily the edges of the lithospheric plates due to the growth of the mass of glaciers above the maximum critical mark, or, their decrease in mass above the minimum critical mark. The glacial process took place in a self-oscillatory regime and was set by the strength characteristics of lithospheric sutures.

Fluctuations in the magnitude of the greenhouse effect of the atmosphere, depending on the content of carbon dioxide, methane and water vapor in it, changes in the albedo of the earth's surface, solar insolation, humidity or dryness of the atmosphere, the action of ice dams, etc., we believe also took place, and each of these reasons played its important, but secondary role. Big Science "overlooked" the glacial threat to the population of the Northern Hemisphere of the Earth, enchanted by the titanic work of Milankovitch's genius and tempted by the ease of explaining the glacial process from the standpoint of the Croll-Milankovitch hypothesis.

Proponents of this hypothesis attribute the onset of a new ice age “out of the kindness of the soul” who is 23 thousand years ahead (Imbri and others), who is 15 thousand years ahead (L.R. Serebryany), who is 5-10 thousand years ahead (B .John). According to the author's system of views, the current interglacial (Holocene) is coming to an end. A full-scale glaciation, sudden and instantaneous by geological standards, with all its horrors, will probably come after the Greenland Ice Sheet melts beyond the critical mark somewhere in the interval of 2020-2050.

1. The reason for the change of glacial phases of the Cenozoic era.

The author, a historian by education, a design engineer by profession, began to work on the subject of ancient glaciations to a certain extent by accident. I just tried to understand more and more for myself, more and more to clarify the meaning, mechanism and dynamics of glacial processes, when I studied the movement of ethnic groups in the process of melting the Eurasian glacier in the Holocene in the context of general work on Slavic-Russian ethnonymy.

When the threat of an unprecedented catastrophe for the historical time was realized, hanging over the population of the Northern Hemisphere, i.e., the threat of a very soon, and most importantly sudden, onset of a new ice age, work on the book was stopped, and the corresponding chapter of the not quite finished book was hastily redone as a report at this conference, fortunately received a kind invitation to speak at it. Of course, it takes a lot of art to raise such a grandiose topic in fifteen pages, but we will try. However, a book and a website are being prepared on the Internet, where our concept will be given in an expanded argument if financial problems are solved.

At the beginning, the latest version of Academician Moskvitin was taken as the basis for periodization from several options, where this author gives eight glacial cycles of Quaternary glaciations, one of them with a question mark (TSB, 5th ed. Anthropogen). Subsequently, the scheme of J. Andrews, presented by him in the book "Winters of our planet", was adopted. M., Mir, 1982, p. 233, close to Moskvitin's scheme, fig. 143, where on the chart of Cenozoic glaciations, there are also eight cycles and already without question marks, but one cycle leaves the Quaternary period in the Pliocene.

The graph, made by the way, like the Moskvitin graphs, is on a non-linear scale, that is, in a form distorted beyond recognition, but convenient for placement on a sheet of paper. The author made a graph of Cenozoic glaciations on a time scale, synthesizing the data of American and Russian glaciologists, but the names of glaciations and interglacials are given as they are usually designated for ice ages in Russia. One of the main conditions for the creation of a consistent theory of glaciations of the Cenozoic era, we consider the explanation of the fact that the continuous succession of glaciations and interglacials of the Cenozoic gradually decreased in time by almost 80 times. We have presented our hypothesis in this paper with this remark in mind.

It should be noted that only the plotting of glacial fluctuations by the author on a time scale, linking each glacial period to the most accurate time according to Moskvitin for Anthropogen and Andrews, for the Pliocene period, the construction of a "glacial sinusoid", allowed us to gradually create our own hypothesis of glacial oscillatory processes of the Cenozoic era. Nevertheless, until recently we believed that there were still several thousand years left before the new ice age.

And only with the next clarification of the factual material on the book of English, American and Canadian glaciologists "Winters of our planet", a figure of 18,000 years surfaced as the actual date of the beginning of the last interglacial. The authors themselves do not claim this, they simply say that by this time the glacier had gained its maximum mass, and that's it. They attribute the beginning of the Holocene to the time of 10,000 thousand years ago, but according to our considerations, the ten thousand-year boundary is the height of the interglacial, and not its beginning.

The Cenozoic glaciations, which began with the creation of the Antarctic ice sheet in the Eocene, the glaciation of Greenland in the Miocene, the emergence of the first grandiose (by the standards of the Cenozoic glaciations) Pliocene glacial oscillation, pass into a continuous series of ever-accelerating glacial cycles of the Quaternary. The Quaternary period, according to Soviet and Russian terminology, is also called the Anthropogen, i.e., in this period, the formation of a modern type of man took place. According to the author of these lines, it was the sharp climate changes in Europe, Africa and the Far East, associated with the ice ages of the Cenozoic and having the character of universal catastrophes, that were the main instrument of anthropogenesis and racegenesis. Unfortunately, the scope of the report does not allow to cover this topic in detail.

Note that both the Quaternary period and the entire Cenozoic era are incomparably small, compared with more ancient periods and eras. So the Quaternary period continues until the present time for about 2.5 million years. Other periods lasted an average of 50 million years. The Quaternary period consists of two epochs: the Pleistocene and the Holocene. The Pleistocene began 2.5 million years ago and continued until 18 thousand years ago (according to the author's periodization system). Holocene - from 18 thousand years ago to the present. The Holocene began with the beginning of the melting of the "Ostashovsky" glacier in the Northern Hemisphere and continues throughout the last interglacial period.

We repeat, the author of the report is a historian by education, and is not a professional glaciologist. He does not have numerous measurements of traces of ancient glaciations, which a professional glaciologist collects all his life. Our research method, our weapon is the use of visualization of graphical representations of glacial fluctuations of the Quaternary period and the entire Cenozoic, made on a linear time scale according to the initial data of professional glaciologists, and the creation, if possible, of a consistent glacial theory that explains the patterns of ancient glaciations appearing on such graphs.

Graph No. 1 (see Table 1) reflected the ice ages of the entire Cenozoic on a time scale in a rectangular form. The graph shows that the duration of ice ages consistently changes over time from very long at the beginning to very short at the end.

On graphs No. 3 and No. 4, the change of glaciations and interglacials is given in the form of sinusoidal curves. The sinusoidal curve emphasizes the oscillatory nature of glacial catastrophes in the Cenozoic and reveals patterns in the succession of glaciations and warm semi-periods (interglacials). It is clearly seen that the periods of climatic fluctuations are becoming shorter and shorter, and the frequency of these fluctuations is increasing.

The first glaciation and the first interglacial of the Pliocene are incomparably long compared to the glaciations and interglacials of the Quaternary (each about 1.6 million years). The first (Oka) glaciation of the Quaternary period also lasts a very long time, about five hundred thousand years. The Toged interglacial also lasts about five hundred thousand years. The next Nizhnebereznikovsky glaciation lasts 500 thousand years, the Likinsky interglacial lasts (attention!) Only 200 thousand years.

The half-period has been shortened by 300,000 years. Why? And why such a reduction did not occur in the first interglacial. Mysteries are waiting to be solved. Further, the Verkhnebereznikovskoe glaciation passes, like the previous interglacial period, in about 200 thousand years. The Ivanovo interglacial lasts (attention!) only 100 thousand years, it has halved in time. Why? The Dnieper glaciation, the largest in terms of the area of ​​the glacier, lasts 100 thousand years.

Odintsovo interglacial, lasts 100 thousand years. The half period did not shorten, it is the same as in the 3rd Ivanovo interglacial. Why? Moscow glaciation follows for 100 thousand years. Fifth, the Mikulin interglacial period lasts only 70 thousand years. Again, a shortening of the half-period of the interglacial period by 30 thousand years. It should be noted that up to this moment, inclusive, all accelerations of climatic fluctuations occurred in interglacials, and then the next glaciation repeated the duration of the interglacial.

After this, the shortening of the time of the semi-periods occurs both during glaciations and during interglacials. The Kalinin glaciation expires in 55,000 years; compared to the Moscow glaciation, it has decreased by 45,000 years. The Mologo-Sheksna interglacial takes only 35 thousand years! The last Ostashev glaciation lasted 22 thousand years. Reduction with the previous Kalinin glaciation by 23 thousand years, more than half. The next interglacial is the Holocene, this is our time, our warm climatic semi-period. How long is the Holocene.

If again the interglacial period is reduced by half (this trend has been established over the last three periods), then the Holocene will last for about 17.5 thousand years. In this light, it is extremely important to know when the Holocene actually began. Comparison of the "theoretical" date and the date of the actual beginning of our interglacial will give us the amount of time left before the start of a new glaciation. The new ice age is a catastrophe of a universal scale, in front of it the explosions of Krakatoa and Sintorin are nothing more than the clapping of children's New Year crackers. It is important not to miscalculate this matter, to accurately understand the essence of the physical processes taking place on Earth in this regard, not to make a mistake with the timing, to find means of neutralizing the extreme threat to the inhabitants of the Northern Hemisphere of our planet.

The limits of the report do not allow even a brief review of the existing theories of ancient glaciations, even such well-known ones as the hypotheses of Milankovitch, Alfred Wegener, Frederic Shoton, E.S. Gernet, Ewing and Donn, Wilson, Nigel Calder, and others. Particular attention should be paid to the hypothesis of a change in the shape of the oceans due to the drift of the continents, and changes in the system of ocean currents as a result. It coincides in its original part with our views. But in revealing the mechanism of the glacial processes of the Quaternary period, we go far from what this hypothesis suggests.

In the beginning, consider the opinion of such a prominent specialist as Brian John. In The Winters of Our Planet, he writes: "The ocean exerts a very strict control over the climate of the earth, mainly as a huge reservoir of heat. Ocean currents also contribute to the transfer of significant amounts of heat from the tropical regions to the polar regions, while cold currents flowing from high latitudes, have a cooling effect on the opposite land masses". p. 61. B. John emphasizes that the separation of Australia from Antarctica in the Oligocene and the interruption of communication between South America and Antarctica led to the fact that for the first time ocean currents could circulate around the Antarctic continent, and this reduced almost to nothing the influx of heat from the equatorial and temperate latitudes .

In the Miocene, the Antarctic ice sheet expanded to a size much larger than today. In the Northern Hemisphere, the drift of the continents did not deprive the North Pole of oceanic water space and the heat of the tropics with currents can enter there under certain conditions. But the northern part of the continents (Asia, Europe, America) moved close to the zone of arctic cold and an unstable glacial situation arose. Br understood this. John.

He seemed to have come to the edge of the abyss, into which the modern civilization of the northern countries, the beauty and pride of modern humanity, its indisputable pole of power, could fall, and what ...? Brian John turned away from the terrible truth and reassured humanity with a pleasant but incorrect prediction. We think that he did this quite conscientiously, confident in his innocence.

In the sixties, Professor J. C. Charlesworth, reviewing numerous theories about the causes of ice ages, was forced to write that they ranged from "improbable to self-contradictory." B. John adds that in the future the situation became even more confused.

Let's take a look at our Cenozoic era ice age charts. What can we say considering the formidable glacial sinusoid. We can say that we have before us an oscillatory circuit, a graph of a self-oscillating mode. The fluctuations are not uniform, the periods are reduced in time, their frequency increases, although there is no strict pattern of frequency increase. In order for the self-oscillatory process to be possible, it is necessary that the growth of the parameter that the graph displays, at a certain stage, becomes the reason for its decrease.

And vice versa, a decrease in the parameter, at a certain stage, turned into the reason for its growth. Let us first consider the growth and decrease of the main parameter of the chart. The main parameter for us is the Quaternary glaciers themselves, this is the increase or decrease in their mass. Thus, in order for the oscillatory process to take place, the mass of the glacier can only grow to a certain level, and its further growth causes the process to reverse, and the mass of the glacier will begin to decrease, glaciation will be replaced by interglacial.

On the contrary, the decrease in the mass of a glacier cannot be infinite; at a certain stage, a decrease in the mass of the glacier will lead to the fact that the process of melting ice will go in the opposite direction, the interglacial will be replaced by a new glaciation. And the reason for this will be the very reduction of the glacial mass. Otherwise, the oscillatory process will stop.

Of course, the argument can be offered not by the mass of the glacier, but by some other parameter, a change in the albedo of the earth's surface, for example, a change in CO 2, or the solar energy entering the earth. But the oscillatory process of the "glaciation-interglacial" system with a gradual increase in the frequency of oscillations in this case will not be able to organize itself. We cannot imagine such a far-fetched process. In nature, everything happens simply and logically.

The reason for the change in the glacial phases of the Cenozoic era, according to our system of views, is a sharp change in ocean currents (warm and cold), when the glacier reaches the critical maximum (in one case) or critical minimum (in the other case) mass.

When the ice sheets of the Northern Hemisphere during the next glaciation reach the maximum critical mass, the earth's crust sags under them in such a way that the system of ocean currents is rebuilt and conditions are created under which the North Atlantic Current (Gulf Stream) goes far to the northeast, into the Barents Sea . In Northern Europe, in Northwest Asia and in North America, a warm interglacial begins.

On the contrary, in the interglacial period, the process of glacier melting continues until the earth's crust, freed from glacial oppression, rises so much that a new restructuring of ocean currents occurs, the Gulf Stream turns south in a large arc, not reaching the Faroe Islands, and instead into the Arctic the warm North Pacific Current (Kuroshio) rushes through the Bering Strait.

There is an extensive literature on the influence of ocean currents on the Earth's climate. In particular, M.S. Barash, W. Ruddiman, A. McIntyre and others found that during periods of global cooling, the speeds increased and the directions of a number of major currents changed, including the Gulf Stream and Kuroshio. Other ocean currents are also being rebuilt, providing a balance of oceanic water exchange. The author believes that the most important feature of the restructuring of ocean currents is that they are discrete, since the bowing or rise of the earth's crust at a certain stage is enhanced by vertical displacements of lithospheric plates at the moment of rupture of lithospheric sutures in rift zones or Benioff zones, when shear stresses reach certain places of critical values.