The Valdai Glaciation is the last ice age of Eastern Europe. Glacier geography and climatic conditions

Same place in 2006. Over 30 years, the glacier retreated 1.9 km.

Glacier retreat- the decline in glaciers around the world observed since the mid-19th century, which significantly affects the availability of stable sources of fresh water, the existence of mountain ecosystems, human use of surrounding areas and, in the long term, water levels in the oceans. The current degradation of glaciers is one of the most pressing issues in glaciology.

The most noticeable losses of glaciation are observed in mountain ranges of temperate and tropical latitudes such as the Tien Shan, Himalayas, Alps, Rocky Mountains. Glaciers of subequatorial and equatorial peaks such as Mount Kilimanjaro, Mount Rwenzori, Mount Kenya, Jaya, northern parts of the Andes - Sierra Nevada De Mérida, Sierra Nevada De Santa Marta, De Cucuy and many volcanoes of Mexico, Colombia and Ecuador , have survived into recent decades. Glacier retreat is often used to provide indirect data on the composition of air and its temperature in modern and past times, but it is worth noting that the dynamics of glacier tongues are not always an indicator of mass balance - the main characteristic of the glacier's condition.

During the Little Ice Age, from about 1550 to 1850, global average air temperatures were somewhat lower than today. After the mid-19th century, the mass balance of many glaciers on the planet took negative values, which was reflected in a decrease in the area and mass of glaciers, mainly due to increased ablation in the lingual part. This retreat slowed or even stopped during a short period of stabilization between 1950 and 1990 (many glaciers of the St. Elias Mountains, Patagonian Ice Sheets, and Scandinavia have a positive mass balance and, to the present day, exhibit advancing tongues, thickening areas of accumulation).

Since the 1980s. Significant global warming has led to a new, much more rapid melting of glaciers around the world, causing many to disappear and many others to be significantly threatened. In some areas, such as the Andes and Himalayas, the disappearance of glaciers will have significant consequences for the supply of fresh water to surrounding communities and local ecosystems. Contemporary destruction of the outlet and shelf glaciers of the Canadian Arctic, Greenland and West Antarctic ice sheets, accelerated by mechanical ablation, could affect sea level rise by measurable amounts, with negative consequences for coastal areas around the world.

The current predominantly negative mass balance of glaciers is associated with an increase in average annual air temperatures, which are subject to a number of cycles, including Milankovitch and solar. The opposite effect (eg, increased moisture in some areas of the world) means improved glaciation conditions. Publications from the second half of the 20th and early 20th centuries note the connection between current trends in increasing average annual air temperatures and human activities (greenhouse effect, etc.). Within the framework of the history of Quaternary paleogeography, for the current thermochron, modern fluctuations, however, are not significant, because in geological time a short series of meteorological observations (about 160 years) does not allow us to determine the significance of the anthropogenic impact.

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An excerpt characterizing the Retreat of Glaciers

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The French troops gradually melted away in a mathematically correct progression. And that crossing of the Berezina, about which so much has been written, was only one of the intermediate stages in the destruction of the French army, and not at all a decisive episode of the campaign. If so much has been and is being written about the Berezina, then on the part of the French this happened only because on the broken Berezina Bridge, the disasters that the French army had previously suffered evenly here suddenly grouped together at one moment and into one tragic spectacle that remained in everyone’s memory. On the Russian side, they talked and wrote so much about the Berezina only because, far from the theater of war, in St. Petersburg, a plan was drawn up (by Pfuel) to capture Napoleon in a strategic trap on the Berezina River. Everyone was convinced that everything would actually happen exactly as planned, and therefore insisted that it was the Berezina crossing that destroyed the French. In essence, the results of the Berezinsky crossing were much less disastrous for the French in terms of the loss of guns and prisoners than Krasnoye, as the figures show.
The only significance of the Berezina crossing is that this crossing obviously and undoubtedly proved the falsity of all plans for cutting off and the justice of the only possible course of action demanded by both Kutuzov and all the troops (mass) - only following the enemy. The crowd of Frenchmen fled with an ever-increasing force of speed, with all their energy directed towards achieving their goal. She ran like a wounded animal, and she could not get in the way. This was proven not so much by the construction of the crossing as by the traffic on the bridges. When the bridges were broken, unarmed soldiers, Moscow residents, women and children who were in the French convoy - all, under the influence of the force of inertia, did not give up, but ran forward into the boats, into the frozen water.
This aspiration was reasonable. The situation of both those fleeing and those pursuing was equally bad. Remaining with his own, each in distress hoped for the help of a comrade, for a certain place he occupied among his own. Having given himself over to the Russians, he was in the same position of distress, but he was on a lower level in terms of satisfying the needs of life. The French did not need to have correct information that half of the prisoners, with whom they did not know what to do, despite all the Russians’ desire to save them, died from cold and hunger; they felt that it could not be otherwise. The most compassionate Russian commanders and hunters of the French, the French in Russian service could not do anything for the prisoners. The French were destroyed by the disaster in which the Russian army was located. It was impossible to take away bread and clothing from hungry, necessary soldiers in order to give it to the French who were not harmful, not hated, not guilty, but simply unnecessary. Some did; but this was only an exception.
Behind was certain death; there was hope ahead. The ships were burned; there was no other salvation but a collective flight, and all the forces of the French were directed towards this collective flight.
The further the French fled, the more pitiful their remnants were, especially after the Berezina, on which, as a result of the St. Petersburg plan, special hopes were pinned, the more the passions of the Russian commanders flared up, blaming each other and especially Kutuzov. Believing that the failure of the Berezinsky Petersburg plan would be attributed to him, dissatisfaction with him, contempt for him and ridicule of him were expressed more and more strongly. Teasing and contempt, of course, were expressed in a respectful form, in a form in which Kutuzov could not even ask what and for what he was accused. They didn't talk to him seriously; reporting to him and asking his permission, they pretended to perform a sad ritual, and behind his back they winked and tried to deceive him at every step.
All these people, precisely because they could not understand him, recognized that there was no point in talking to the old man; that he would never understand the full depth of their plans; that he would answer with his phrases (it seemed to them that these were just phrases) about the golden bridge, that you cannot come abroad with a crowd of vagabonds, etc. They had already heard all this from him. And everything he said: for example, that we had to wait for food, that people were without boots, it was all so simple, and everything they offered was so complex and clever that it was obvious to them that he was stupid and old, but they were not powerful, brilliant commanders.

Photo: Israel Angel Mijangos EPA/EFE

In the summer of 2013, scientists at a research station at Laval University discovered a 54-year-old note. In 1959, American geologist Paul Walker put it in a bottle and buried it in a pile of rocks on Ward Hunt Island in Canada near a glacier. The message contained instructions - whoever finds the note must measure the distance from the find to the edge of the glacier.

Those who found the note followed the instructions and were shocked - in 1959, the distance from the stones to the glacier measured by Walker was 51 meters. In 2013 it grew to 122 meters!

All over the Earth, mountains are losing their snow-ice cover. The usually called eternal mountain snow and ice turned out to be not so durable.

The same thing happens with permafrost in Russia, ice fields in the Yukon and glaciers in New Zealand. Warming temperatures are puzzling archaeologists, giving hope to relatives of missing climbers and revealing the secrets of past plane crashes.

A "deposit" of reindeer manure that has been frozen for thousands of years is thawing in the Yukon. At the top of Mexico's highest volcano, Pico de Orizaba, popular with mountain climbers in training, people are found dead in avalanches.

The body of a climber who disappeared in November 1959 was recently discovered. During excavations, another body was discovered nearby. Then news came of another discovery at the top of the volcano. Judging by his clothing, which was completely inappropriate for climbing, he was a victim of a small plane crash that occurred here in 1999.

Finds are multiplying all over the world: airplane wreckage, mummies of Incan children, a cemetery of ancient reptiles hidden under a glacier in Chile... Archaeologists even opened a specialized publication “Journal of Glacial Archaeology”.

Its editor, James Dixon, an anthropologist from the University of New Mexico, laments that for every discovery recorded, up to a thousand remain unknown. Melted bodies decompose very quickly. If we have time, we get truly unique things, for example, baskets, feathered arrows, and leather goods perfectly preserved in ice.

In 1999, mountain archaeologists discovered three child mummies in the Argentine Andes. This is the highest Inca burial site ever discovered. Apparently, these were ritual sacrifices - to appease the mountain spirits and deliver a message to the other world.
In 2010, tourists in Canada came across the body of American William Holland, who was buried in an avalanche in 1989.

Recently, in New Zealand, relatives buried a young climber, David Eric Moen. His body was found 42 years after an avalanche near Mount Cook.

There are more and more such cases all over the world.

During the so-called "White War", soldiers of the Austro-Hungarian Empire fought Italian troops in the mountains. Almost a century later, about 100 mummified bodies have been found.

The Mendenhall Glacier in Alaska “discovered” an ancient forest for scientists - branches, roots, and trunks of ancient trees up to 2,000 years old began to emerge from under the ice.

The wreckage of a plane that crashed in Alaska in 1952 has been found. There were 52 passengers on board.

The Norwegian Lendbreen glacier in Norway “showed” what Iron Age clothing looked like. In 2011, a unique handmade woolen tunic was found, made, as two years of research showed, more than 1,500 years ago.

Unfortunately, climate change not only helps solve the mysteries of the past, but also creates more and more new problems. Negative forecasts from scientists are multiplying year after year.

Yet the discovery has prompted a number of alarming claims that global warming could “awaken ancient diseases from their hibernation.” Some scientists are raising the possibility that pathogenic microbes that infected ancient people may be “awakening.” How the modern human immune system will react to this is not yet clear.

A recent report in The Lancet found that climate change could reverse the health gains of the last 50 years.

The report was prepared by European and Chinese climate scientists, geographers, ecologists, sociologists, and experts in the field of energy and medicine. The report's authors believe that if global temperatures rise by 4 degrees Celsius, the inevitable extreme weather events will increase the risk of infectious diseases.

"We believe climate change is a major driver of human health, yet it is often ignored in policy," Anthony Costello, director of the Institute of Global Health at University College, told a news conference in London.

Another important statement was made recently from the opposite direction from science. In the first environmental encyclical in history, the Pope said: “Climate is a common good, belonging to all and affecting all. At the global level, it is a highly complex system associated with many conditions necessary to support human life. A strong scientific consensus confirms that today we are witnessing a dangerous warming of the climate system.

In past decades, this warming has been accompanied by a steady rise in sea levels and what appears to be an increase in the number of extreme weather events - even if it is difficult to scientifically prove the link to climate change in any given case."

As you can see, many politicians, scientists, and clergy agree on the consequences of climate change and on the need for urgent and radical action. The very near future will show whether deeds will keep pace with words.

The last ice age ended 12,000 years ago. During the most severe period, glaciation threatened man with extinction. However, after the glacier disappeared, he not only survived, but also created a civilization.

Glaciers in the history of the Earth

The last glacial era in the history of the Earth is the Cenozoic. It began 65 million years ago and continues to this day. Modern man is lucky: he lives in an interglacial period, one of the warmest periods in the life of the planet. The most severe glacial era - the Late Proterozoic - is far behind.

Despite global warming, scientists predict the onset of a new ice age. And if the real one will come only after millennia, then the little ice age, which will reduce annual temperatures by 2-3 degrees, may come quite soon.

The glacier became a real test for man, forcing him to invent means for his survival.

Last Ice Age

The Würm or Vistula glaciation began approximately 110,000 years ago and ended in the tenth millennium BC. The peak of cold weather occurred 26-20 thousand years ago, the final stage of the Stone Age, when the glacier was at its largest.

Little Ice Ages

Even after the glaciers melted, history has known periods of noticeable cooling and warming. Or, in another way - climate pessimums And optimums. Pessimums are sometimes called Little Ice Ages. In the XIV-XIX centuries, for example, the Little Ice Age began, and during the Great Migration of Nations there was an early medieval pessimum.

Hunting and meat food

There is an opinion according to which the human ancestor was more of a scavenger, since he could not spontaneously occupy a higher ecological niche. And all known tools were used to cut up the remains of animals that were taken from predators. However, the question of when and why people began to hunt is still a matter of debate.

In any case, thanks to hunting and meat food, ancient man received a large supply of energy, which allowed him to better endure the cold. The skins of killed animals were used as clothing, shoes and walls of the home, which increased the chances of survival in the harsh climate.

Upright walking

Upright walking appeared millions of years ago, and its role was much more important than in the life of a modern office worker. Having freed his hands, a person could engage in intensive housing construction, clothing production, processing of tools, and the production and preservation of fire. The upright ancestors moved freely in open areas, and their life no longer depended on collecting the fruits of tropical trees. Already millions of years ago, they moved freely over long distances and obtained food in river drains.

Upright walking played an insidious role, but it still became more of an advantage. Yes, man himself came to cold regions and adapted to life in them, but at the same time he could find both artificial and natural shelters from the glacier.

Fire

Fire in the life of ancient man was initially an unpleasant surprise, not a blessing. Despite this, the human ancestor first learned to “extinguish” it, and only later use it for his own purposes. Traces of the use of fire are found in sites that are 1.5 million years old. This made it possible to improve nutrition by preparing protein foods, as well as to remain active at night. This further increased the time to create survival conditions.

Climate

The Cenozoic Ice Age was not a continuous glaciation. Every 40 thousand years, human ancestors had the right to a “respite” - temporary thaws. At this time, the glacier was retreating and the climate became milder. During periods of harsh climate, natural shelters were caves or regions rich in flora and fauna. For example, the south of France and the Iberian Peninsula were home to many early cultures.

The Persian Gulf 20,000 years ago was a river valley rich in forests and grassy vegetation, a truly “antediluvian” landscape. Wide rivers flowed here, one and a half times larger in size than the Tigris and Euphrates. The Sahara in certain periods became a wet savannah. The last time this happened was 9,000 years ago. This can be confirmed by rock paintings that depict an abundance of animals.

Fauna

Huge glacial mammals, such as bison, woolly rhinoceros and mammoth, became an important and unique source of food for ancient people. Hunting such large animals required a lot of coordination and brought people together noticeably. The effectiveness of “teamwork” has proven itself more than once in the construction of parking lots and the manufacture of clothing. Deer and wild horses enjoyed no less “honor” among ancient people.

Language and communication

Language was perhaps the main life hack of ancient man. It was thanks to speech that important technologies for processing tools, making and maintaining fire, as well as various human adaptations for everyday survival were preserved and passed on from generation to generation. Perhaps the details of hunting large animals and migration directions were discussed in Paleolithic language.

Allörd warming

Scientists are still arguing whether the extinction of mammoths and other glacial animals was the work of man or caused by natural causes - the Allerd warming and the disappearance of food plants. As a result of the extermination of a large number of animal species, people in harsh conditions faced death from lack of food. There are known cases of the death of entire cultures simultaneously with the extinction of mammoths (for example, the Clovis culture in North America). However, warming became an important factor in the migration of people to regions whose climate became suitable for the emergence of agriculture.

Around the world, which significantly affects the availability of stable fresh water sources, the existence of mountain ecosystems, human use of surrounding areas and, in the long term, water levels in the oceans. Like glaciers in general, this phenomenon is being studied by glaciologists, who link it to atmospheric warming caused by increased greenhouse gases due to human activities. The most noticeable ice sheet losses occur in temperate mountain ranges, such as the Himalayas, Alps, Rocky Mountains, and Southern Andes, and isolated tropical peaks such as Kilimanjaro. Often the retreat of glaciers is used to track air temperatures in modern and past times.

During the Little Ice Age, from about 1550 to 1850, global average temperatures were somewhat lower than today. After this, until about 1940, glaciers began to retreat as air temperatures gradually increased. This retreat slowed or even stopped during the brief period of global cooling between 1950 and 1980. However, since 1980, significant global warming has led to a new, much more rapid melting of glaciers around the world, with the result that many have already disappeared and the existence of many others is significantly threatened. In some areas, such as the Andes and Himalayas, the disappearance of glaciers will have significant consequences for the supply of fresh water to surrounding communities and local ecosystems. The current rapid collapse of the marginal glaciers of the Greenland and West Antarctic ice sheets, which began around 1985, may be a harbinger of significant rises in ocean levels that will have devastating consequences for coastal areas around the world.

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See what “Glacier retreat” is in other dictionaries:

I; Wed 1. to Retreat retreat (2 3, 5 6 digits). O. glaciers. O. in front of superior enemy forces. O. from old customs. 2. Insert in which l. presentation that differs from the main topic. Make o. Lyrical about... Encyclopedic Dictionary

retreat- I; Wed 1) to retreat retreat 2), 3), 5), 6) Retreat of glaciers. Retreating before superior enemy forces. Departure from old customs. 2) Insert in which l. presentation that differs from the main topic... Dictionary of many expressions

This term has other meanings, see Ganges (meanings). Ganges गङ्गा ... Wikipedia

- (from de... and lat. glacies ice), retreat of glaciers, reduction in the length of valley glaciers in mountainous countries or retreat of the edge of the cover after its maximum development. Deglaciation occurs as a result of warming (or increasing dryness) ... ... Ecological dictionary

Antarctic Peninsula ... Wikipedia

The Earth's climate periodically undergoes serious changes associated with alternating large-scale cold snaps, accompanied by the formation of stable ice sheets on the continents, and warming. The last ice age, which ended approximately 11-10 thousand years ago, for the territory of the East European Plain is called the Valdai glaciation.

Systematics and terminology of periodic cold spells

The longest periods of general cooling in the history of the climate of our planet are called cryoeras, or glacial eras lasting up to hundreds of millions of years. Currently, the Cenozoic cryoera has been ongoing on Earth for about 65 million years and, apparently, will continue for a very long time (judging by previous similar stages).

Over the course of eons, scientists have identified ice ages interspersed with phases of relative warming. Periods can last millions and tens of millions of years. The modern ice age is Quaternary (the name is given in accordance with the geological period) or, as is sometimes said, Pleistocene (according to a smaller geochronological division - epoch). It began approximately 3 million years ago and, apparently, is still far from complete.

In turn, ice ages consist of shorter-term - several tens of thousands of years - ice ages, or glaciations (the term “glacial” is sometimes used). The warm intervals between them are called interglacials, or interglacials. We now live precisely during such an interglacial era, which replaced the Valdai glaciation on the Russian Plain. Glaciations, although they have undoubted common features, are characterized by regional characteristics, and therefore are named after a particular area.

Within epochs, stages (stadials) and interstadials are distinguished, during which the climate experiences short-term fluctuations - pessimums (cold snaps) and optima. The present time is characterized by the climatic optimum of the sub-Atlantic interstadial.

Age of the Valdai glaciation and its phases

According to the chronological framework and conditions of division into stages, this glacier is somewhat different from the Würm (Alps), Vistula (Central Europe), Wisconsin (North America) and other corresponding glaciations. On the East European Plain, the beginning of the era that replaced the Mikulin interglacial is dated back to about 80 thousand years ago. It should be noted that establishing clear time boundaries is a serious difficulty - as a rule, they are blurred - therefore the chronological framework of the stages fluctuates significantly.

Most researchers distinguish two stages of the Valdai glaciation: the Kalininskaya with maximum ice approximately 70 thousand years ago and the Ostashkovskaya (about 20 thousand years ago). They are separated by the Bryansk Interstadial - a warming that lasted from approximately 45-35 to 32-24 thousand years ago. Some scientists, however, propose a more detailed division of the era - up to seven stages. As for the retreat of the glacier, it occurred over a period of 12.5 to 10 thousand years ago.

Glacier geography and climatic conditions

The center of the last glaciation in Europe was Fennoscandia (including the territories of Scandinavia, the Gulf of Bothnia, Finland and Karelia with the Kola Peninsula). From here the glacier periodically expanded to the south, including onto the Russian Plain. It was less extensive in scope than the previous Moscow glaciation. The boundary of the Valdai ice sheet ran in a northeastern direction and did not reach Smolensk, Moscow, or Kostroma at its maximum. Then, on the territory of the Arkhangelsk region, the border turned sharply north to the White and Barents seas.

In the center of the glaciation, the thickness of the Scandinavian ice sheet reached 3 km, which is comparable to the glacier of the East European Plain, which had a thickness of 1-2 km. Interestingly, while the ice cover was significantly less developed, the Valdai glaciation was characterized by harsh climatic conditions. Average annual temperatures during the last glacial maximum - Ostashkovsky - were only slightly higher than the temperatures of the era of the very powerful Moscow glaciation (-6 °C) and were 6-7 °C lower than today.

Consequences of glaciation

The ubiquitous traces of the Valdai glaciation on the Russian Plain indicate the strong influence it had on the landscape. The glacier erased many of the irregularities left by the Moscow glaciation, and formed during its retreat, when a huge amount of sand, debris and other inclusions melted from the ice mass, deposits up to 100 meters thick.

The ice cover did not advance as a continuous mass, but in differentiated flows, along the sides of which piles of fragmentary material—marginal moraines—formed. These are, in particular, some ridges within the current Valdai Upland. In general, the entire plain is characterized by a hilly-moraine surface, for example, a large number of drumlins - low elongated hills.

Very clear traces of glaciation are lakes formed in hollows plowed by a glacier (Ladoga, Onega, Ilmen, Chudskoye and others). The river network of the region also acquired its modern appearance as a result of the influence of the ice sheet.

The Valdai glaciation changed not only the landscape, but also the composition of the flora and fauna of the Russian Plain, influenced the area of ​​settlement of ancient man - in a word, it had important and multifaceted consequences for this region.