When will the ice age on earth. Ice Ages. Ice rink the size of the world
We are at the mercy of autumn and it's getting colder. Are we moving towards an ice age, one of the readers wonders.
The fleeting Danish summer is behind us. The leaves are falling from the trees, the birds are flying south, it's getting darker and, of course, colder too.
Our reader Lars Petersen from Copenhagen has begun to prepare for the cold days. And he wants to know how seriously he needs to prepare.
“When does the next ice age start? I learned that glacial and interglacial periods alternate regularly. Since we live in an interglacial period, it is logical to assume that the next ice age is ahead of us, right? he writes in a letter to the Ask Science section (Spørg Videnskaben).
We in the editorial office shudder at the thought of the cold winter that lies in wait for us at that end of autumn. We, too, would love to know if we are on the verge of an ice age.
The next ice age is still far away
Therefore, we addressed Sune Olander Rasmussen, lecturer at the Center for Basic Ice and Climate Research at the University of Copenhagen.
Sune Rasmussen studies the cold and gets information about past weather, storms, Greenland glaciers and icebergs. In addition, he can use his knowledge in order to fulfill the role of "foreteller of ice ages."
“In order for an ice age to occur, several conditions must coincide. We cannot accurately predict when the ice age will begin, but even if humanity did not further influence the climate, our forecast is that the conditions for it will develop in the best case in 40-50 thousand years,” Sune Rasmussen reassures us.
Since we are still talking to the “Ice Age predictor”, we can get some more information about what these “conditions” are in question in order to understand a little more about what the Ice Age actually is.
What is an ice age
Sune Rasmussen relates that during the last ice age the earth's average temperature was a few degrees cooler than it is today, and that the climate at higher latitudes was colder.
Much of the northern hemisphere was covered in massive ice sheets. For example, Scandinavia, Canada and some other parts of North America were covered with a three-kilometer ice sheet.
The huge weight of the ice cover pressed the earth's crust a kilometer into the Earth.
Ice ages are longer than interglacials
However, 19 thousand years ago, changes in the climate began to occur.
This meant that the Earth gradually became warmer, and over the next 7,000 years, freed itself from the cold grip of the Ice Age. After that, the interglacial period began, in which we are now.
Context
New ice age? Not soon
The New York Times June 10, 2004ice Age
Ukrainian truth 25.12.2006 In Greenland, the last remnants of the shell came off very abruptly 11,700 years ago, or to be precise, 11,715 years ago. This is evidenced by the studies of Sune Rasmussen and his colleagues.This means that 11,715 years have passed since the last ice age, and this is a completely normal interglacial length.
“It's funny that we usually think of the Ice Age as an 'event', when in fact it's just the opposite. The middle ice age lasts 100 thousand years, while the interglacial lasts from 10 to 30 thousand years. That is, the Earth is more often in an ice age than vice versa.
“The last couple of interglacials lasted only about 10,000 years each, which explains the widely held but erroneous belief that our current interglacial is nearing its end,” says Sune Rasmussen.
Three Factors Influence the Possibility of an Ice Age
The fact that the Earth will plunge into a new ice age in 40-50 thousand years depends on the fact that there are small variations in the orbit of the Earth around the Sun. Variations determine how much sunlight hits which latitudes, and thereby affects how warm or cold it is.
This discovery was made by the Serbian geophysicist Milutin Milanković almost 100 years ago and is therefore known as the Milanković cycle.
Milankovitch cycles are:
1. The orbit of the Earth around the Sun, which changes cyclically about once every 100,000 years. The orbit changes from nearly circular to more elliptical, and then back again. Because of this, the distance to the Sun changes. The farther the Earth is from the Sun, the less solar radiation our planet receives. In addition, when the shape of the orbit changes, so does the length of the seasons.
2. The tilt of the earth's axis, which fluctuates between 22 and 24.5 degrees relative to the orbit of rotation around the Sun. This cycle spans approximately 41,000 years. 22 or 24.5 degrees - it seems not such a significant difference, but the tilt of the axis greatly affects the severity of the different seasons. The more the Earth is tilted, the greater the difference between winter and summer. The Earth's axial tilt is currently at 23.5 and is decreasing, which means that differences between winter and summer will decrease over the next thousand years.
3. The direction of the earth's axis relative to space. The direction changes cyclically with a period of 26 thousand years.
“The combination of these three factors determines whether there are prerequisites for the beginning of the ice age. It is almost impossible to imagine how these three factors interact, but with the help of mathematical models we can calculate how much solar radiation receives certain latitudes at certain times of the year, as well as received in the past and will receive in the future,” says Sune Rasmussen.
Snow in summer leads to ice age
Summer temperatures play a particularly important role in this context.
Milankovitch realized that for the ice age to start, summers in the northern hemisphere would have to be cold.
If the winters are snowy and most of the northern hemisphere is covered in snow, then the temperatures and hours of sunshine in the summer determine whether the snow is allowed to remain all summer.
“If the snow does not melt in the summer, then little sunlight penetrates the Earth. The rest is reflected back into space in a snow-white veil. This exacerbates the cooling that began due to a change in the orbit of the Earth around the Sun,” says Sune Rasmussen.
“Further cooling brings even more snow, which further reduces the amount of absorbed heat, and so on, until the ice age begins,” he continues.
Similarly, a period of hot summers leads to the end of the Ice Age. The hot sun then melts the ice enough so that sunlight can again reach dark surfaces like soil or the sea, which absorb it and warm the Earth.
Humans are delaying the next ice age
Another factor that is relevant to the possibility of an ice age is the amount of carbon dioxide in the atmosphere.
Just as snow that reflects light increases the formation of ice or accelerates its melting, the increase in carbon dioxide in the atmosphere from 180 ppm to 280 ppm (parts per million) helped bring the Earth out of the last ice age.
However, ever since industrialization began, people have been pushing the CO2 share further all the time, so it's almost 400 ppm now.
“It took nature 7,000 years to raise the share of carbon dioxide by 100 ppm after the end of the ice age. Humans have managed to do the same in just 150 years. This is of great importance for whether the Earth can enter a new ice age. This is a very significant influence, which means not only that an ice age cannot begin at the moment,” says Sune Rasmussen.
We thank Lars Petersen for the good question and send the winter gray T-shirt to Copenhagen. We also thank Sune Rasmussen for the good answer.
We also encourage our readers to submit more scientific questions to [email protected]
Did you know?
Scientists always talk about the ice age only in the northern hemisphere of the planet. The reason is that there is too little land in the southern hemisphere on which a massive layer of snow and ice can lie.
With the exception of Antarctica, the entire southern part of the southern hemisphere is covered with water, which does not provide good conditions for the formation of a thick ice shell.
The materials of InoSMI contain only assessments of foreign media and do not reflect the position of the editors of InoSMI.
History of the Ice Age.
The causes of ice ages are cosmic: a change in the activity of the Sun, a change in the position of the Earth relative to the Sun. Planetary cycles: 1). 90 - 100 thousand-year cycles of climate change as a result of changes in the eccentricity of the earth's orbit; 2). 40 - 41 thousand-year cycles of change in the inclination of the earth's axis from 21.5 degrees. up to 24.5 degrees; 3). 21 - 22 thousand-year cycles of change in the orientation of the earth's axis (precession). The results of volcanic activity - the darkening of the earth's atmosphere with dust and ash - have a significant impact.
The oldest glaciation was 800 - 600 million years ago in the Laurentian period of the Precambrian era.
About 300 million years ago, the Permian Carboniferous glaciation occurred at the end of the Carboniferous - the beginning of the Permian period of the Paleozoic era. At that time, the only supercontinent Pangea was on planet Earth. The center of the continent was at the equator, the edge reached the south pole. Ice ages were replaced by warming, and those - again by cold snaps. Such climate changes lasted from 330 to 250 million years ago. During this time, Pangea shifted to the north. About 200 million years ago, an even warm climate was established on Earth for a long time.
About 120 - 100 million years ago, during the Cretaceous period of the Mesozoic era, the mainland Gondwana broke away from the Pangea mainland and remained in the Southern Hemisphere.
At the beginning of the Cenozoic era, in the early Paleogene in the Paleocene epoch - ca. 55 million years ago there was a general tectonic uplift of the earth's surface by 300 - 800 meters, the split of Pangea and Gondwana into continents and a global cooling began. 49 - 48 million years ago, at the beginning of the Eocene epoch, a strait formed between Australia and Antarctica. About 40 million years ago mountain continental glaciers began to form in West Antarctica. During the entire Paleogene period, the configuration of the oceans changed, the Arctic Ocean, the Northwest Passage, the Labrador and Baffin Seas, and the Norwegian-Greenland Basin formed. High blocky mountains rose along the northern shores of the Atlantic and Pacific Oceans, and the underwater Mid-Atlantic Ridge developed.
On the border of the Eocene and Oligocene - about 36 - 35 million years ago, Antarctica moved to the South Pole, separated from South America and was cut off from the warm equatorial waters. 28 - 27 million years ago in Antarctica, continuous covers of mountain glaciers were formed and then, during the Oligocene and Miocene, the ice sheet gradually filled the entire Antarctica. The mainland Gondwana finally split into continents: Antarctica, Australia, Africa, Madagascar, Hindustan, South America.
15 million years ago glaciation began in the Arctic Ocean - floating ice, icebergs, sometimes solid ice fields.
10 million years ago, a glacier in the Southern Hemisphere went beyond Antarctica into the ocean and reached its maximum about 5 million years ago, covering the ocean with an ice sheet to the coasts of South America, Africa, and Australia. Floating ice reached the tropics. At the same time, in the Pliocene era, glaciers began to appear in the mountains of the continents of the Northern Hemisphere (Scandinavian, Ural, Pamir-Himalayan, Cordillera) and 4 million years ago filled the islands of the Canadian Arctic Archipelago and Greenland. North America, Iceland, Europe, North Asia were covered with ice 3 - 2.5 million years ago. The Late Cenozoic Ice Age reached its maximum in the Pleistocene epoch, about 700 thousand years ago. This ice age continues to this day.
So, 2 - 1.7 million years ago, the Upper Cenozoic - Quaternary period began. Glaciers in the Northern Hemisphere on land have reached mid-latitudes, in the Southern continental ice has reached the edge of the shelf, icebergs up to 40-50 degrees. Yu. sh. During this period, about 40 stages of glaciation were observed. The most significant were: Plestocene glaciation I - 930 thousand years ago; Plestocene glaciation II - 840 thousand years ago; Danube glaciation I - 760 thousand years ago; Danube glaciation II - 720 thousand years ago; Danube glaciation III - 680 thousand years ago.
During the Holocene epoch, there were four glaciations on Earth, named after valleys.
Swiss rivers, where they were first studied. The most ancient is the Gyunts glaciation (in North America - Nebraska) 600 - 530 thousand years ago. Gunz I reached its maximum 590 thousand years ago, Gunz II peaked 550 thousand years ago. Glaciation Mindel (Kansasian) 490 - 410 thousand years ago. Mindel I reached its maximum 480 thousand years ago, the peak of Mindel II was 430 thousand years ago. Then came the Great Interglacial, which lasted 170 thousand years. During this period, the Mesozoic warm climate seemed to return, and the ice age ended forever. But he returned.
The Riss glaciation (Illinois, Zaalsk, Dnieper) began 240 - 180 thousand years ago, the most powerful of all four. Riess I reached its maximum 230 thousand years ago, the peak of Riess II was 190 thousand years ago. The thickness of the glacier in the Hudson Bay reached 3.5 kilometers, the edge of the glacier in the mountains of the North. America reached almost to Mexico, on the plain filled the basins of the Great Lakes and reached the river. Ohio, went south along the Appalachians and went to the ocean in the southern part of about. Long Island. In Europe, the glacier filled all of Ireland, Bristol Bay, the English Channel at 49 degrees. from. sh., North Sea at 52 degrees. from. sh., passed through Holland, southern Germany, occupied all of Poland to the Carpathians, Northern Ukraine, descended in tongues along the Dnieper to the rapids, along the Don, along the Volga to Akhtuba, along the Ural Mountains and then went along Siberia to Chukotka.
Then came a new interglacial period, which lasted more than 60 thousand years. Its maximum fell on 125 thousand years ago. In Central Europe at that time there were subtropics, moist deciduous forests grew. Subsequently, they were replaced by coniferous forests and dry prairies.
115 thousand years ago, the last historical glaciation of Würm (Wisconsin, Moscow) began. It ended about 10 thousand years ago. The early Würm peaked ca. 110 thousand years ago and ended approx. 100 thousand years ago. The largest glaciers covered Greenland, Svalbard, the Canadian Arctic Archipelago. 100 - 70 thousand years ago interglacial reigned on Earth. Middle Würm - c. 70 - 60 thousand years ago, was much weaker than the Early, and even more so the Late. The last ice age - Late Wurm was 30 - 10 thousand years ago. The maximum glaciation occurred in the period 25 - 18 thousand years ago.
The stage of the greatest glaciation in Europe is called Egga I - 21-17 thousand years ago. Due to the accumulation of water in glaciers, the level of the World Ocean has dropped by 120 - 100 meters below the current one. 5% of all water on Earth was in glaciers. About 18 thousand years ago, a glacier in the North. America reached 40 degrees. from. sh. and Long Island. In Europe, the glacier reached the line: about. Iceland - about. Ireland - Bristol Bay - Norfolk - Schleswig - Pomerania - Northern Belarus - suburbs of Moscow - Komi - Middle Urals at 60 degrees. from. sh. - Taimyr - Putorana Plateau - Chersky Ridge - Chukotka. Due to the lowering of the sea level, the land in Asia was located north of the Novosibirsk Islands and in the northern part of the Bering Sea - "Beringia". Both Americas were connected by the Isthmus of Panama, which blocked the communication of the Atlantic Ocean with the Pacific Ocean, as a result of which a powerful Gulf Stream was formed. There were many islands in the middle part of the Atlantic Ocean from America to Africa, and the largest among them was the island of Atlantis. The northern tip of this island was at the latitude of the city of Cadiz (37 degrees N). The archipelagos of Azores, Canaries, Madeira, Cape Verde are the flooded peaks of the outlying ranges. Ice and polar fronts from the north and south came as close as possible to the equator. The water in the Mediterranean Sea was 4 degrees. With colder modern. The Gulf Stream, rounding Atlantis, ended off the coast of Portugal. The temperature gradient was larger, the winds and currents were stronger. In addition, there were extensive mountain glaciations in the Alps, in Tropical Africa, the mountains of Asia, in Argentina and Tropical South America, New Guinea, Hawaii, Tasmania, New Zealand, and even in the Pyrenees and the mountains of north-west. Spain. The climate in Europe was polar and temperate, vegetation - tundra, forest-tundra, cold steppes, taiga.
The Egg II stage was 16 - 14 thousand years ago. The glacier began to slowly retreat. At the same time, a system of glacier-dammed lakes formed near its edge. Glaciers with a thickness of up to 2 - 3 kilometers with their mass pressed down and lowered the continents into magma and thereby raised the ocean floor, mid-ocean ridges were formed.
About 15 - 12 thousand years ago, the civilization of the "Atlanteans" arose on an island heated by the Gulf Stream. "Atlantes" created a state, an army, had possessions in North Africa to Egypt.
Early Dryas (Luga) stage 13.3 - 12.4 thousand years ago. The slow retreat of the glaciers continued. About 13 thousand years ago, a glacier in Ireland melted.
Tromso-Lyngen stage (Ra; Bölling) 12.3 - 10.2 thousand years ago. About 11 thousand years ago
the glacier melted on the Shetland Islands (the last in Great Britain), in Nova Scotia and on about. Newfoundland (Canada). 11 - 9 thousand years ago, a sharp rise in the level of the World Ocean began. When the glacier was released from the load, the land began to rise and the bottom of the oceans to sink, tectonic changes in the earth's crust, earthquakes, volcanic eruptions, and floods. Atlantis also perished from these cataclysms around 9570 BC. The main centers of civilization, cities, the majority of the population perished. The remaining "Atlanteans" partly degraded and ran wild, partly died out. Possible descendants of the "Atlanteans" were the "Guanches" tribe in the Canary Islands. Information about Atlantis was preserved by the Egyptian priests and told about it to the Greek aristocrat and legislator Solon c. 570 BC Solon's narrative was rewritten and brought to posterity by the philosopher Plato c. 350 BC
Preboreal stage 10.1 - 8.5 thousand years ago. Global warming has begun. In the Azov-Black Sea region, there was a regression of the sea (a decrease in area) and water desalination. 9.3 - 8.8 thousand years ago the glacier melted in the White Sea and Karelia. About 9 - 8 thousand years ago, the fjords of Baffin Island, Greenland, Norway were freed from ice, the glacier on the island of Iceland retreated 2 - 7 kilometers from the coast. 8.5 - 7.5 thousand years ago, the glacier melted on the Kola and Scandinavian peninsulas. But the warming was uneven, in the Late Holocene there were 5 cooling periods. The first - 10.5 thousand years ago, the second - 8 thousand years ago.
7 - 6 thousand years ago, glaciers in the polar regions and mountains assumed, in the main, their modern outlines. 7 thousand years ago there was a climatic optimum on Earth (the highest average temperature). The current average global temperature is 2 degrees C lower, and if it drops another 6 degrees C, a new ice age will begin.
About 6.5 thousand years ago, a glacier was localized on the Labrador Peninsula in the Torngat Mountains. Approximately 6 thousand years ago, Beringia finally sank and the land "bridge" between Chukotka and Alaska disappeared. The third cooling in the Holocene happened 5.3 thousand years ago.
About 5,000 years ago, civilizations formed in the valleys of the Nile, Tigris and Euphrates, Indus rivers and the modern historical period began on planet Earth. 4000 - 3500 years ago, the level of the World Ocean became equal to the current level. The fourth cooling in the Holocene was about 2800 years ago. Fifth - "Little Ice Age" in 1450 - 1850. with a minimum of approx. 1700 The global mean temperature was 1 degree C lower than today. There were harsh winters, cold summers in Europe, Sev. America. Frozen bay in New York. Mountain glaciers have greatly increased in the Alps, the Caucasus, Alaska, New Zealand, Lapland and even the Ethiopian highlands.
Currently, the interglacial period continues on Earth, but the planet continues its space journey and global changes and climate transformations are inevitable.
Hello readers! I have prepared a new article for you. I would like to talk about the ice age on Earth.Let's figure out how these ice ages come, what are the causes and consequences ...
Ice Age on Earth.
Imagine for a moment that the cold has shackled our planet, and the landscape has turned into an icy desert (more about deserts), over which ferocious northern winds rage. Our Earth looked like this during the ice age - from 1.7 million to 10,000 years ago.
About the process of formation of the Earth keeps memories of almost every corner of the globe. Hills running like a wave beyond the horizon, mountains touching the sky, a stone that was taken by man to build cities - each of them has his own story.
These clues, in the course of geological research, can tell us about a climate (about climate change) that was significantly different from today.
Our world was once bound by a thick sheet of ice that carved its way from the frozen poles to the equator.
Earth was a gloomy and gray planet in the grip of cold, carried by snowstorms from the north and south.
Frozen planet.
From the nature of the glacial deposits (deposited clastic material) and the surfaces worn away by the glacier, geologists concluded that in fact there were several periods.
Back in the Precambrian period, about 2300 million years ago, the first ice age began, and the last, and best studied, took place between 1.7 million years ago and 10,000 years ago in the so-called. Pleistocene epoch. It is simply called the Ice Age.
thaw.
These ruthless clutches were avoided by some lands, where it was usually also cold, but winter did not reign on the whole Earth.
Vast areas of deserts and tropical forests were located in the region of the equator. For the survival of many species of plants, reptiles and mammals, these warm oases played a significant role.
In general, the climate of the glacier was not always cold. Glaciers, before receding, crawled several times from north to south.
In some parts of the planet, the weather between ice advances was even warmer than today. For example, the climate in southern England was almost tropical.
Paleontologists, thanks to the fossilized remains, claim that elephants and hippos once roamed the banks of the Thames.
Such periods of thaw - also known as interglacial stages - lasted several hundred thousand years until the cold returned.
Ice streams moving south again left behind destruction, thanks to which geologists can accurately determine their path.
On the body of the Earth, the movement of these large masses of ice left "scars" of two types: sedimentation and erosion.
When a moving mass of ice wears away the soil along its path, erosion occurs. Entire valleys in the bedrock were hollowed out by rock fragments brought by the glacier.
Like a gigantic grinding machine that polished the ground beneath it and created large furrows called glacial shading, the movement of crushed stone and ice acted.
The valleys widened and deepened over time, acquiring a distinct U-shape.
When a glacier (about what glaciers are) dumped the rock fragments that it carried, deposits formed. This usually happened when the ice melted, leaving piles of coarse gravel, fine-grained clay and huge boulders scattered over a vast area.
Causes of glaciation.
What is called glaciation, scientists still do not know exactly. Some believe that the temperature at the Earth's poles, for the past millions of years, is lower than at any time in the history of the Earth.
Continental drift (more on continental drift) could be the cause. About 300 million million years ago there was only one giant supercontinent - Pangea.
The split of this supercontinent occurred gradually, and as a result, the movement of the continents left the Arctic Ocean almost completely surrounded by land.
Therefore, now, unlike in the past, there is only a slight mixing of the waters of the Arctic Ocean with warm waters to the south.
It comes down to this situation: the ocean never warms up well in summer, and is constantly covered with ice.
Antarctica is located at the South Pole (more about this continent), which is very far from warm currents, which is why the mainland sleeps under the ice.
The cold is returning.
There are other reasons for global cooling. According to assumptions, one of the reasons is the degree of inclination of the earth's axis, which is constantly changing. Together with the irregular shape of the orbit, this means that the Earth is further from the Sun at some periods than at others.
And if the amount of solar heat changes even by a percentage, this can lead to a difference in temperature on Earth by a whole degree.
The interaction of these factors will be enough to start a new ice age. It is also believed that the ice age may cause the accumulation of dust in the atmosphere as a result of its pollution.
Some scientists believe that when a giant meteor collided with the Earth, the age of dinosaurs ended. This led to the fact that a huge cloud of dust and dirt rose into the air.
Such a catastrophe could block the receipt of the rays of the Sun (more about the Sun) through the atmosphere (more about the atmosphere) of the Earth and cause it to freeze. Similar factors may contribute to the beginning of a new ice age.
In about 5,000 years, some scientists predict a new ice age will begin, while others argue that the ice age never ended.
Considering that the last Pleistocene Ice Age stage ended 10,000 years ago, it is possible that we are now experiencing an interglacial stage, and the ice may return some time later.
On this note, I end this topic. I hope that the story about the ice age on Earth did not “freeze” you 🙂 And finally, I suggest you subscribe to the mailing list of fresh articles so as not to miss their release.
In the history of the Earth, there were long periods when the entire planet was warm - from the equator to the poles. But there were also times so cold that glaciations reached those regions that currently belong to the temperate zones. Most likely, the change of these periods was cyclical. During warmer times, there could be relatively little ice, and it was only in the polar regions or on the tops of mountains. An important feature of ice ages is that they change the nature of the earth's surface: each glaciation affects the appearance of the Earth. By themselves, these changes may be small and insignificant, but they are permanent.
History of Ice Ages
We do not know exactly how many ice ages there have been throughout the history of the Earth. We know of at least five, possibly seven, ice ages, starting with the Precambrian, in particular: 700 million years ago, 450 million years ago (Ordovician), 300 million years ago - Permo-Carboniferous glaciation, one of the largest ice ages, affecting the southern continents. The southern continents refer to the so-called Gondwana, an ancient supercontinent that included Antarctica, Australia, South America, India and Africa.
The most recent glaciation refers to the period in which we live. The Quaternary period of the Cenozoic era began about 2.5 million years ago, when the glaciers of the Northern Hemisphere reached the sea. But the first signs of this glaciation date back 50 million years ago in Antarctica.
The structure of each ice age is periodic: there are relatively short warm epochs, and there are longer periods of icing. Naturally, cold periods are not the result of glaciation alone. Glaciation is the most obvious consequence of cold periods. However, there are quite long intervals that are very cold, despite the absence of glaciations. Today, examples of such regions are Alaska or Siberia, where it is very cold in winter, but there is no glaciation, because there is not enough rainfall to provide enough water for the formation of glaciers.
Discovery of ice ages
The fact that there are ice ages on Earth has been known to us since the middle of the 19th century. Among the many names associated with the discovery of this phenomenon, the first is usually the name of Louis Agassiz, a Swiss geologist who lived in the middle of the 19th century. He studied the glaciers of the Alps and realized that they were once much more extensive than they are today. It wasn't just him who noticed. In particular, Jean de Charpentier, another Swiss, also noted this fact.
It is not surprising that these discoveries were made mainly in Switzerland, since there are still glaciers in the Alps, although they are melting quite quickly. It is easy to see that once the glaciers were much larger - just look at the Swiss landscape, the troughs (glacial valleys) and so on. However, it was Agassiz who first put forward this theory in 1840, publishing it in the book "Étude sur les glaciers", and later, in 1844, he developed this idea in the book "Système glaciare". Despite initial skepticism, over time, people began to realize that this was indeed true.
With the advent of geological mapping, especially in Northern Europe, it became clear that earlier glaciers had a huge scale. Then there were extensive discussions about how this information relates to the Flood, because there was a conflict between geological evidence and biblical teachings. Initially, glacial deposits were called deluvial because they were considered evidence of the Flood. Only later it became known that such an explanation is not suitable: these deposits were evidence of a cold climate and extensive glaciation. By the beginning of the 20th century, it became clear that there were many glaciations, and not just one, and from that moment this area of science began to develop.
Ice Age Research
Known geological evidence of ice ages. The main evidence for glaciations comes from the characteristic deposits formed by glaciers. They are preserved in the geological section in the form of thick ordered layers of special deposits (sediments) - diamicton. These are simply glacial accumulations, but they include not only deposits of a glacier, but also deposits of melt water formed by its flows, glacial lakes or glaciers moving into the sea.
There are several forms of glacial lakes. Their main difference is that they are a water body enclosed by ice. For example, if we have a glacier that rises into a river valley, then it blocks the valley like a cork in a bottle. Naturally, when ice blocks a valley, the river will still flow and the water level will rise until it overflows. Thus, a glacial lake is formed through direct contact with ice. There are certain deposits that are contained in such lakes that we can identify.
Due to the way glaciers melt, which depends on seasonal changes in temperature, there is an annual melting of ice. This leads to an annual increase in minor sediments falling from under the ice into the lake. If we then look into the lake, we see stratification (rhythmic layered sediments) there, which is also known by the Swedish name "varves" (varve), which means "annual accumulations". So we can actually see annual layering in glacial lakes. We can even count these varves and find out how long this lake has existed. In general, with the help of this material, we can get a lot of information.
In Antarctica, we can see huge ice shelves that come off the land into the sea. And of course, ice is buoyant, so it floats on water. As it swims, it carries pebbles and minor sediments with it. Due to the thermal action of the water, the ice melts and sheds this material. This leads to the formation of the process of the so-called rafting of rocks that go into the ocean. When we see fossil deposits from this period, we can find out where the glacier was, how far it extended, and so on.
Causes of glaciation
Researchers believe that ice ages occur because the Earth's climate depends on the uneven heating of its surface by the Sun. So, for example, the equatorial regions, where the Sun is almost vertically overhead, are the warmest zones, and the polar regions, where it is at a large angle to the surface, are the coldest. This means that the difference in heating of different parts of the Earth's surface controls the ocean-atmospheric machine, which is constantly trying to transfer heat from the equatorial regions to the poles.
If the Earth were an ordinary sphere, this transfer would be very efficient, and the contrast between the equator and the poles would be very small. So it was in the past. But since there are now continents, they get in the way of this circulation, and the structure of its flows becomes very complex. Simple currents are restrained and altered, in large part by mountains, leading to the circulation patterns we see today that drive the trade winds and ocean currents. For example, one of the theories about why the ice age began 2.5 million years ago links this phenomenon with the emergence of the Himalayan mountains. The Himalayas are still growing very fast and it turns out that the existence of these mountains in a very warm part of the Earth governs things like the monsoon system. The beginning of the Quaternary Ice Age is also associated with the closing of the Isthmus of Panama, which connects the north and south of America, which prevented the transfer of heat from the equatorial Pacific to the Atlantic.
If the position of the continents relative to each other and relative to the equator allowed the circulation to work efficiently, then it would be warm at the poles, and relatively warm conditions would persist throughout the earth's surface. The amount of heat received by the Earth would be constant and vary only slightly. But since our continents create serious barriers to circulation between north and south, we have pronounced climatic zones. This means that the poles are relatively cold while the equatorial regions are warm. When things are happening as they are now, the Earth can change with variations in the amount of solar heat it receives.
These variations are almost completely constant. The reason for this is that over time the earth's axis changes, as does the earth's orbit. Given this complex climatic zoning, orbital change could contribute to long-term changes in climate, resulting in climate wobble. Because of this, we have not continuous icing, but periods of icing, interrupted by warm periods. This happens under the influence of orbital changes. The latest orbital changes are seen as three separate phenomena: one 20,000 years long, the second 40,000 years long, and the third 100,000 years long.
This led to deviations in the pattern of cyclic climate change during the Ice Age. The icing most likely occurred during this cyclic period of 100,000 years. The last interglacial epoch, which was as warm as the current one, lasted about 125,000 years, and then came a long ice epoch, which took about 100,000 years. We are now living in another interglacial era. This period will not last forever, so another ice age awaits us in the future.
Why do ice ages end?
Orbital changes change the climate, and it turns out that ice ages are characterized by alternating cold periods, which can last up to 100,000 years, and warm periods. We call them the glacial (glacial) and interglacial (interglacial) epochs. An interglacial era is usually characterized by conditions similar to what we see today: high sea levels, limited areas of icing, and so on. Naturally, even now there are glaciations in Antarctica, Greenland and other similar places. But in general, the climatic conditions are relatively warm. This is the essence of interglacial: high sea level, warm temperature conditions and, in general, a fairly even climate.
But during the ice age, the average annual temperature changes significantly, the vegetative belts are forced to shift north or south, depending on the hemisphere. Regions like Moscow or Cambridge become uninhabited, at least in winter. Although they may be habitable in summer due to the strong contrast between seasons. But what is actually happening is that the cold zones are expanding substantially, the average annual temperature is dropping, and the overall climate is getting very cold. While the largest glacial events are relatively limited in time (perhaps around 10,000 years), the entire long cold period can last 100,000 years or more. This is what the glacial-interglacial cycle looks like.
Due to the length of each period, it is difficult to say when we will exit the current era. This is due to plate tectonics, the location of the continents on the surface of the Earth. Currently, the North Pole and South Pole are isolated, with Antarctica at the South Pole and the Arctic Ocean to the north. Because of this, there is a problem with heat circulation. As long as the location of the continents does not change, this ice age will continue. In line with long-term tectonic changes, it can be assumed that it will take another 50 million years in the future until significant changes occur that allow the Earth to emerge from the ice age.
Geological implications
This frees up huge sections of the continental shelf that are flooded today. This will mean, for example, that one day it will be possible to walk from Britain to France, from New Guinea to Southeast Asia. One of the most critical places is the Bering Strait, which links Alaska with Eastern Siberia. It is quite small, about 40 meters, so if the sea level drops to a hundred meters, then this area will become land. This is also important because plants and animals will be able to migrate through these places and get into regions where they cannot go today. Thus, the colonization of North America depends on the so-called Beringia.
Animals and the Ice Age
It is important to remember that we ourselves are the "products" of the ice age: we evolved during it, so we can survive it. However, it is not a matter of individual individuals - it is a matter of the entire population. The problem today is that there are too many of us and our activities have significantly changed the natural conditions. Under natural conditions, many of the animals and plants that we see today have a long history and survive the ice age well, although there are some that evolved slightly. They migrate and adapt. There are zones in which animals and plants survived the Ice Age. These so-called refugiums were located further north or south from their present distribution.
But as a result of human activity, some species died or became extinct. This has happened on every continent, with the possible exception of Africa. A huge number of large vertebrates, namely mammals, as well as marsupials in Australia, were exterminated by man. This was caused either directly by our activities, such as hunting, or indirectly by the destruction of their habitat. Animals living in northern latitudes today lived in the Mediterranean in the past. We have destroyed this region so much that it will most likely be very difficult for these animals and plants to colonize it again.
Consequences of global warming
Under normal conditions, by geological standards, we would soon enough return to the Ice Age. But because of global warming, which is a consequence of human activity, we are postponing it. We will not be able to completely prevent it, since the causes that caused it in the past still exist today. Human activity, an unforeseen element of nature, affects atmospheric warming, which may have already caused a delay in the next glacial.
Today, climate change is a very relevant and exciting issue. If the Greenland Ice Sheet melts, sea levels will rise by six meters. In the past, during the previous interglacial epoch, which was about 125,000 years ago, the Greenland Ice Sheet melted profusely, and sea levels were 4–6 meters higher than today. It's certainly not the end of the world, but it's not time complexity either. After all, the Earth has recovered from catastrophes before, it will be able to survive this one.
The long-term outlook for the planet is not bad, but for humans, that's a different matter. The more research we do, the better we understand how the Earth is changing and where it leads, the better we understand the planet we live on. This is important because people are finally starting to think about changing sea levels, global warming and the impact of all these things on agriculture and the population. Much of this has to do with the study of ice ages. Through these studies, we will learn the mechanisms of glaciation, and we can use this knowledge proactively in an attempt to mitigate some of the changes that we ourselves are causing. This is one of the main results and one of the goals of research on ice ages.
Of course, the main consequence of the Ice Age is huge ice sheets. Where does water come from? Of course, from the oceans. What happens during ice ages? Glaciers form as a result of precipitation on land. Due to the fact that the water does not return to the ocean, the sea level falls. During the most severe glaciations, sea levels can drop by more than a hundred meters.
Just at the time of the powerful development of all forms of life on our planet, a mysterious ice age begins with its new temperature fluctuations. We have already spoken about the reasons for the appearance of this ice age before.
Just as the change of seasons brought about the selection of better, more adaptable animals and the creation of diverse breeds of mammals, so now, in this Ice Age, man is emerging from the mammals, in an even more painful struggle against the advancing glaciers than the fight against the millennium-spanning change of seasons. Here it was not enough just one adaptation by a significant change in the body. What was needed was a mind that would be able to turn nature itself to its advantage and conquer it.
We have finally reached the highest stage of the development of life: . He took possession of the Earth, and his mind, developing further and further, learned to embrace the entire universe. With the advent of man, a completely new era of creation truly began. We are still on one of its lower levels, we are the simplest among beings endowed with a mind that dominates the forces of nature. The beginning of the path to unknown majestic goals has come!
There have been at least four great ice ages, which, in turn, break up again into smaller waves of temperature fluctuations. Warmer periods lay between the ice ages; then, thanks to the melting glaciers, the damp valleys were covered with lush meadow vegetation. Therefore, it was during these interglacial periods that herbivores could develop especially well.
In the deposits of the Quaternary epoch, which closes the ice ages, and in the deposits of the Deluvian epoch, which followed the last general glaciation of the globe, and of which our time is a direct continuation, we come across huge pachyderms, namely the mammoth mastodon, the fossilized remains of which we still now we often find in the tundra of Siberia. Even with this giant, the primitive man dared to get involved in the struggle, and, in the end, he emerged victorious from it.
Mastodon (restored) of the Deluvian era.
We involuntarily return in thought again to the emergence of the world, if we look at the flowering of the beautiful present from the chaotic dark primitive conditions. The fact that in the second half of our investigations we remained all the time only on our small Earth is due to the fact that we know all these different stages of development only on it. But, taking into account the similarity of the matter that forms the world everywhere and the universality of the forces of nature that control matter, we will come to complete agreement of all the main features of the formation of the world that we can observe in the sky.
We have no doubt that in the distant universe there must be millions more worlds like our Earth, although we do not have any exact information about them. On the contrary, it is precisely among the relatives of the Earth, the rest of the planets of our solar system, which we can better explore, thanks to their greater proximity to us, that have characteristic differences from our Earth, as, for example, sisters of very different ages. Therefore, we should not be surprised if we do not find traces of life on them, similar to the life of our Earth. Also, Mars with its channels remains a mystery to us.
If we look up at the sky strewn with millions of Suns, then we can be sure that we will meet the gazes of living beings who look at our daylight in the same way we look at their Sun. Perhaps we are not so far from the time when, having mastered all the forces of nature, a person will be able to penetrate into these expanses of the universe and send a signal beyond our globe to living beings located on another celestial body - and receive an answer from them .
Just as life, at least otherwise we cannot imagine it, came to us from the universe and spread over the Earth, starting with the simplest, so man, in the end, will expand the narrow horizon that encompasses his earthly world, and will communicate with other worlds of the universe, from where these primary elements of life on our planet came. The universe belongs to man, his mind, his knowledge, his strength.
But no matter how high fantasy lifts us, we will someday fall down again. The cycle of development of the worlds consists in rise and fall.
ice age on earth
After terrible downpours, like a flood, it became damp and cold. From the high mountains, the glaciers slid lower and lower into the valleys, because the Sun could no longer melt the masses of snow continuously falling from above. As a result, even those places where earlier during the summer the temperature was still above zero were also covered with ice for a long time. We are now seeing something similar in the Alps, where individual "tongues" of glaciers descend well below the boundary of eternal snows. In the end, much of the plains at the foot of the mountains were also covered with ever higher piles of ice. A general ice age has come, the traces of which we can indeed observe everywhere on the entire globe.
It is necessary to recognize the enormous merit of the world traveler Hans Meyer from Leipzig for the evidence he found that both on Kilimanjaro and on the Cordillera of South America, even in tropical regions, glaciers everywhere at that time descended much lower than at present. The connection here between that extraordinary volcanic activity and the onset of the ice age was first proposed by the Sarazen brothers in Basel. How did this happen?
The following question can be answered after careful research. The entire chain of the Andes, during geological periods, which, of course, are calculated in hundreds of thousands and millions of years, was formed simultaneously, and its volcanoes were the result of this grandiose mountain-forming process on Earth. At this time, almost the entire Earth was dominated by approximately tropical temperature, which, however, very soon after that should have been replaced by a strong general cooling.
Penck established that there were at least four great ice ages, with warmer periods in between. But it seems that these great ice ages are divided into a still greater number of smaller periods of time in which more insignificant general temperature fluctuations took place. From this one can see what turbulent times the Earth was going through and in what constant agitation the air ocean was then.
How long this time lasted can only be indicated very roughly. It has been calculated that the beginning of this ice age can be placed about half a million years ago. Since the last “little glaciation”, in all likelihood, only 10 to 20 millennia have passed, and we are now living, probably, only in one of those “interglacial periods” that happened before the last general glaciation.
Through all these ice ages there are traces of primitive man developing from an animal. The legends about the flood, which have come down to us from primitive times, may stand in connection with the events described above. The Persian legend almost certainly points to volcanic phenomena that preceded the beginning of the great flood.
This Persian legend describes the great flood as follows: “From the south rose a great fiery dragon. Everything was devastated by him. Day turned into night. The stars are gone. The zodiac was covered by a huge tail; only the sun and moon could be seen in the sky. Boiling water fell to the Earth and scorched the trees to the very roots. Raindrops the size of a human head fell among the frequent lightning. Water covered the Earth higher than a man's height. Finally, after the dragon fight lasted 90 days and 90 nights, the enemy of the Earth was destroyed. A terrible storm arose, the water receded, the dragon plunged into the depths of the Earth.
This dragon, according to the famous Viennese geologist Suess, was nothing more than a highly active volcano, the fiery eruption of which spread across the sky like a long tail. All other phenomena described in the legend are quite consistent with the phenomena observed after a strong volcanic eruption.
Thus, on the one hand, we have shown that after the splitting and collapse of a huge block, the size of a mainland, a series of volcanoes should have formed, the eruptions of which were followed by floods and glaciations. On the other hand, we have before our eyes a number of volcanoes in the Andes, located on a huge cliff of the Pacific coast, and we also proved that soon after the emergence of these volcanoes, an ice age began. The tales of the flood complete the picture of this turbulent period in the development of our planet even more. During the eruption of Krakatoa, we observed on a small scale, but in all details, the consequences of the volcano sinking into the depths of the sea.
Taking into account all of the above, we will hardly doubt that the relationship between these phenomena was, indeed, such as we assumed. Thus, the entire Pacific Ocean, in fact, arose as a result of the separation and failure of its present bottom, which before that was a huge continent. Was it "the end of the world" in the sense that it is commonly understood? If the fall happened suddenly, then it was probably the most terrible and grandiose catastrophe that the Earth has ever seen since organic life appeared on it.
This question is now, of course, difficult to answer. But still we can say the following. If the collapse on the coast of the Pacific Ocean had taken place gradually, then those terrible volcanic eruptions would have remained completely inexplicable, which at the end of the "Tertiary era" occurred along the entire chain of the Andes and whose very weak consequences are still observed there.
If the coastal region were to sink there so slowly that whole centuries were required to detect this sinking, as we still observe at the present time near some sea coasts, then even then all movements of masses in the interior of the Earth would occur very slowly, and only occasionally would occur. volcanic eruptions.
In any case, we see that there are counteractions to these forces that produce shifts in the earth's crust, otherwise the sudden tremors of earthquakes could not take place. But we also had to admit that the stresses resulting from these counteractions cannot become too great, because the earth's crust turns out to be plastic, pliable for large, but slowly acting forces. All these considerations lead us to the conclusion, perhaps against our will, that these catastrophes must have manifested precisely sudden forces.