Customs / 20.01.2022

Gallery of ice sculptures on Krasnaya Presnya (closed). Festivals of snow and ice sculptures in different countries Blue River, Greenland glaciers

In the mountains of Shanxi province in China, there is the country's largest ice cave - an 85-meter underground structure in the shape of a bowling pin - located on the side of a mountain. Its walls and floor are covered with a thick layer of ice, and large icicles and stalactites hang from ceiling to floor. Ningwu Cave has one unique feature: it remains frozen throughout the summer, even when outside temperatures rise to summer highs.

Throughout Continental Europe, Central Asia and North America, there are many such ice caves where winter lasts all year round. Most are located in colder regions such as Alaska, Iceland and Russia, where the low temperatures that persist throughout the year help keep the caves frozen. However, ice caves can also be found in warmer climates.

Ningu Ice Cave in China. Photo Credit: Zhou Junxiang/Image China

Most of these caves are so-called "cold traps". These caves are conveniently located with crevices and openings that allow cold air to enter in winter, and through which warm air cannot enter in summer. In winter, cold dense air settles in the cave, displacing any warm air that has gathered here, which rises up and leaves the caves. During the summer, cold air remains in the cave as the relatively warm air rises and cannot enter.

The ice inside the cave also acts as a buffer, helping to stabilize the temperature inside. The ice immediately cools any incoming warm air from outside before it can cause significant warming inside the cave. Of course, under his influence, the ice melts, but the temperature inside the cave remains almost unchanged. There is also the opposite effect: in winter, when very cold air enters the cave, any liquid water freezes, releasing heat and preventing the temperature in the cave from falling too low.

Ice caves also require sufficient water for the right amount of time to form. In winter, the climate must be such that there is enough snow on the mountains, and in summer the temperature must be high enough to melt, but the air in the cave is not too warm. In order for an ice cave to form and be maintained, there must be a delicate balance between all of these factors.

The largest ice cave in the world is the Eisriesenwelt, located in Werfen, Austria, about 40 km south of Salzburg. The cave stretches for more than 42 kilometers. Photo: Michael & Sophia/Flickr

The Decorah Ice Cave in Iowa, USA is one of the largest ice caves in the American Midwest. The cave remains relatively ice-free in autumn and early winter. During this period, cold winter air enters the cave and lowers the temperature of the stone walls. When the snow begins to melt in the spring, meltwater seeps into the cave and freezes on contact with the still cold walls, and in May-June the ice layer reaches a maximum thickness of several centimeters. The ice often remains inside the cave until the end of August, while the outside temperature rises above 30 degrees.

A similar phenomenon is observed at the Coudersport Ice Mine in Pennsylvania. This is a small cave where ice forms only in the summer months and melts in the winter. Photo credit: rivercouple75/Tripadvisor

The booming Ice Chasm in the Canadian Rockies in Alberta is known for its incredible acoustics. It is said that when the stones fall off and fall to the floor of the cave, 140 meters down, it causes a rumbling echo. The cave was only discovered in 2005 using Google Earth. Photo: Francois-Xavier De Ruydts

Ningu Ice Cave in China. Photo: Zhou Junxiang/Image China

Nagoya University (Japan) Dedicated to my family, Yeoul, Kostya and Stas. Glaciers on Earth and in the Solar System About ten percent of the land is covered with glaciers - perennial masses of snow, firn (from German Firn - last year's packed granular snow) and ice, which have their own movement. These huge rivers of ice, cutting through valleys and grinding down mountains, crushing continents with their weight, store 80% of our planet's fresh water reserves. Pamir is one of the main centers of modern glaciation of the planet - inaccessible and little explored (Tajikistan; photo by the author, 2009) The role of glaciers in the evolution of the globe and man is colossal. The last 2 million years of ice ages have become a powerful impetus for development for primates. Severe weather forced the hominid to struggle for existence in cold conditions, life in caves, the appearance and development of clothing, and the widespread use of fire. The sea level dropped due to the growth of glaciers and the drying of many isthmuses contributed to the migration of ancient people to America, Japan, Malaysia and Australia.

The largest centers of modern glaciation include:

Antarctica - terra incognita, discovered only 190 years ago and became the record holder for the absolute minimum temperature on Earth: -89.4 ° C (1974); at this temperature, kerosene freezes;
Greenland, deceptively called the Greenland, is the "icy heart" of the Northern Hemisphere;
the Canadian Arctic Archipelago and the majestic Cordillera, where one of the most picturesque and powerful centers of glaciation - Alaska, is located, a real modern relic of the Pleistocene;
the most grandiose region of glaciation in Asia - the “abode of snows” the Himalayas and Tibet;
"roof of the world" Pamir;
Andes;
"heavenly mountains" Tien Shan and "black scree" Karakorum;
Surprisingly, there are even glaciers in Mexico, tropical Africa (the “sparkling mountain” of Kilimanjaro, Mount Kenya and the Rwenzori Mountains) and New Guinea!

The science that studies glaciers and other natural systems whose properties and dynamics are determined by ice is called glaciology (from Latin glacies - ice). "Ice" is a mono-mineral rock that occurs in 15 crystalline modifications for which there are no names, but only code numbers. They differ in different types of crystal symmetry (or shape of the unit cell), the number of oxygen atoms in the cell, and other physical parameters. The most common modification is hexagonal, but there are also cubic and tetragonal, etc. We conditionally designate all these modifications of the solid phase of water with one single word “ice”.

Ice and glaciers are found everywhere in the solar system: in the shadow of the craters of Mercury and the Moon; in the form of permafrost and polar caps of Mars; in the core of Jupiter, Saturn, Uranus and Neptune; on Europa - the satellite of Jupiter, completely, like a shell, covered with many kilometers of ice; on other satellites of Jupiter - Ganymede and Callisto; on one of the moons of Saturn - Enceladus, with the purest ice in the Solar System, where jets of water vapor burst hundreds of kilometers high from cracks in the ice shell at supersonic speed; possibly on the satellites of Uranus - Miranda, Neptune - Triton, Pluto - Charon; finally, in comets. However, by coincidence of astronomical circumstances, the Earth is a unique place where the existence of water on the surface is possible in three phases at once - liquid, solid and gaseous.

The fact is that ice is a very young mineral of the Earth. Ice is the latest and most superficial mineral, not only in terms of specific gravity: If we single out the temperature stages of differentiation of matter in the process of the formation of the Earth as an initially gaseous body, then ice formation is the last step. It is for this reason that snow and ice on the surface of our pallet are everywhere near the melting point and are subject to the slightest changes in climate.

The crystalline phase of water is ice. Model photo:

E. Podolsky, 2006

But if, under the temperature conditions of the Earth, water passes from one phase to another, then for cold Mars (with a temperature difference from –140°C to +20°C), water is mainly in the crystalline phase (although there are sublimation processes that even lead to the formation clouds), and much more significant phase transitions are no longer experienced by water, but by carbon dioxide, falling as snow when the temperature drops, or evaporating when it rises (thus, the mass of the Martian atmosphere changes from season to season by 25%).

Growth and melting of glaciers

For the emergence of a glacier, a combination of climatic conditions and relief is necessary, under which the annual amount of snowfall (including snowstorms and avalanches) will exceed the loss (ablation) due to melting and evaporation. Under such conditions, a mass of snow, firn and ice arises, which, under the influence of its own weight, begins to flow down the slope.

The glacier is of atmospheric sedimentary origin. In other words, every gram of ice, be it a modest glacier in the Khibiny or a giant ice dome of Antarctica, was brought by weightless snowflakes that fall year after year, millennium after millennium in the cold regions of our planet. Thus, glaciers are a temporary stop of water between the atmosphere and the ocean.

Accordingly, if glaciers grow, then the level of the world's oceans drops (for example, to 120 m during the last ice age); if they shrink and retreat, then the sea rises. One of the consequences of this is the existence in the shelf zone of the Arctic regions of relic underwater permafrost, covered by the water column. During the epochs of glaciation, the continental shelf, which was exposed due to lowering of the sea level, gradually froze through. After the re-emergence of the sea, the permafrost formed in this way was under the water of the Arctic Ocean, where it still exists due to the low temperature of sea water (-1.8°C).

If all the world's glaciers melted, sea levels would rise by 64–70 meters. Now the annual advance of the sea on land occurs at a rate of 3.1 mm per year, of which about 2 mm is the result of an increase in the volume of water due to thermal expansion, and the remaining millimeter is the result of the intensive melting of the mountain glaciers of Patagonia, Alaska and the Himalayas. Recently, this process has been accelerating, increasingly affecting the glaciers of Greenland and West Antarctica, and, according to the latest estimates, sea level rise by 2100 could be 200 cm. This will significantly change the coastline, erase more than one island from the world map and take hundreds million people in prosperous Netherlands and poor Bangladesh, in the countries of the Pacific Ocean and the Caribbean, in other parts of the globe, coastal areas with a total area of more than 1 million square kilometers.

types of glaciers. icebergs

Glaciologists distinguish the following main types of glaciers: mountain peak glaciers, ice domes and shields, slope glaciers, valley glaciers, network glacier systems (typical, for example, for Svalbard, where ice completely fills valleys, and only mountain tops remain above the surface of the glacier). In addition, as a continuation of land glaciers, sea glaciers and ice shelves are distinguished, which are floating or resting on the bottom of a plate with an area of \u200b\u200bup to several hundred thousand square kilometers (the largest ice shelf, the Ross Glacier in Antarctica, occupies 500 thousand km 2, which is approximately equal to the territory of Spain).

The ships of James Ross at the base of the Earth's largest ice shelf, discovered by him in 1841. Engraving, Mary Evans Picture Library, London; adapted from Bailey, 1982

Ice shelves rise and fall with the ebb and flow of the tides. From time to time, giant ice islands break off from them - the so-called table icebergs, up to 500 m thick. Only one tenth of their volume is above the water, which is why the movement of icebergs depends more on sea currents, and not on winds and because for which icebergs have repeatedly become the cause of the death of ships. Since the Titanic tragedy, the icebergs have been closely monitored. Nevertheless, iceberg disasters still occur today - for example, the crash of the Exxon Valdez oil tanker on March 24, 1989 off the coast of Alaska occurred when the ship was trying to avoid colliding with an iceberg.

An unsuccessful attempt by the US Coast Survey to secure a shipping channel off the coast of Greenland (UPI, 1945;

adapted from Bailey, 1982)

The tallest iceberg recorded in the Northern Hemisphere was 168 meters high. And the largest table iceberg ever described was observed on November 17, 1956 from the USS Glacier icebreaker: its length was 375 km, its width was more than 100 km, and its area was more than 35 thousand km 2 (larger than Taiwan or Kyushu)!

US Navy icebreakers try in vain to push an iceberg out of the seaway (Collection of Charles Swithinbank; adapted from Bailey, 1982)

Since the 1950s, the commercial transportation of icebergs to countries experiencing a shortage of fresh water has been seriously discussed. In 1973, one of these projects was proposed - with a budget of 30 million dollars. This project attracted the attention of scientists and engineers from all over the world; It was led by Saudi Prince Mohammed al-Faisal. But due to numerous technical problems and unresolved issues (for example, an iceberg that has turned over due to melting and a shift in the center of mass can, like an octopus, drag any cruiser towing it to the bottom), the implementation of the idea is postponed for the future.

A tugboat churns the sea with full engine power to deflect an iceberg from a collision course with an oil exploration vessel (Harald Sund for Life, 1981; adapted from Bailey, 1982)

Wrapping an iceberg incommensurable in size with any ship on the planet and transporting an ice island melting in warm waters and shrouded in fog across thousands of kilometers of the ocean is still beyond human strength. foggy ice island across thousands of kilometers of the ocean - yet beyond the power of man.

Examples of iceberg transportation projects. Art by Richard Schlecht; adapted from Bailey, 1982

It is curious that when melting, the ice of an iceberg hisses like soda ("bergy selzer") - this can be seen in any polar institute if you are treated to a glass of whiskey with pieces of such ice. This ancient air, compressed under high pressure (up to 20 atmospheres), escapes from the bubbles when it melts. The air was trapped during the transformation of snow into firn and ice, after which it was compressed by the enormous pressure of the mass of the glacier. The story of the 16th-century Dutch navigator Willem Barents has been preserved about how the iceberg, near which his ship was standing (near Novaya Zemlya), suddenly shattered into hundreds of pieces with a terrible noise, horrifying all the people on board.

Glacier Anatomy

The glacier is conditionally divided into two parts: the upper one is the feeding area, where the accumulation and transformation of snow into firn and ice takes place, and the lower one is the ablation zone, where the snow accumulated during the winter melts. The line separating these two regions is called the glacier feeding boundary. The newly formed ice gradually flows from the upper feeding region to the lower ablation region, where melting occurs. Thus, the glacier is included in the process of geographic moisture exchange between the hydrosphere and the troposphere.

Irregularities, ledges, an increase in the slope of the glacial bed change the relief of the glacial surface. In steep places where stresses in the ice are extremely high, ice falls and cracks can occur. The Himalayan glacier Chatoru (mountainous region Lagul, Lahaul) begins with a grandiose icefall 2100 m high! The real mess of giant columns and towers of ice (the so-called seracs) of the icefall is literally impossible to cross.

The infamous icefall on the Nepalese Khumbu glacier at the foot of Everest has cost the lives of many climbers trying to pass through this devilish surface. In 1951, a group of climbers led by Sir Edmund Hillary, during a reconnaissance of the surface of the glacier, along which the route of the first successful ascent of Everest was later laid, crossed this forest of ice columns up to 20 meters high. As one of the participants recalled, a sudden rumble and a strong trembling of the surface under their feet greatly frightened the climbers, but, fortunately, the collapse did not occur. One of the subsequent expeditions, in 1969, ended tragically: 6 people were crushed under the tones of unexpectedly collapsed ice.

Climbers avoid a crack in the ill-fated Khumbu Glacier while climbing Mount Everest (Chris Bonington from Bruce Coleman, Ltd., Middlesex, England, 1972; adapted from Bailey, 1982)

The depth of cracks in glaciers can exceed 40 meters, and their length can be several kilometers. Covered with snow, such dips into the darkness of the glacial body are a death trap for climbers, snowmobiles or even all-terrain vehicles. Over time, due to the movement of ice, cracks can close. There are cases when non-evacuated bodies of people who fell into cracks were literally frozen into the glacier. So, in 1820, on the slope of Mont Blanc, three guides were knocked down and thrown into the rift by an avalanche - only 43 years later their bodies were found melted next to the tongue of the glacier, three kilometers from the site of the tragedy.

Left: Photograph by legendary 19th-century photographer Vittorio Sella capturing climbers approaching a glacier fissure in the French Alps (1888, Istituto di Fotografia Alpina, Biella, Italy; adapted from Bailey, 1982). Right: Giant cracks on the Fedchenko Glacier (Pamir, Tajikistan; photo by the author, 2009)

Melt water can significantly deepen the cracks and turn them into part of the drainage system of the glacier - glacial wells. They can reach 10 m in diameter and penetrate hundreds of meters deep into the glacial body to the very bottom.

Moulin - glacial well on the Fedchenko glacier (Pamir, Tajikistan; photo by the author, 2009)

A lake of meltwater on the surface of a glacier in Greenland, 4 km long and 8 meters deep, was recently recorded as disappearing in less than an hour and a half; while the water flow per second was greater than that of Niagara Falls. All this water reaches the ice bed and serves as a lubricant that speeds up the sliding of ice.

Meltwater stream on the surface of the Fedchenko Glacier in the ablation zone (Pamir, Tajikistan; photo by the author, 2009)

Glacier speed

Naturalist and mountaineer Franz Josef Hugi in 1827 made one of the first measurements of the speed of ice movement, and unexpectedly for himself. A hut was built on the glacier for the night; when Hugi returned to the glacier a year later, he was surprised to find that the hut was in a completely different place.

The movement of glaciers is due to two different processes - sliding of the glacial mass under its own weight along the bed and viscoplastic flow (or internal deformation, when ice crystals change shape under the action of stresses and shift relative to each other).

Ice crystals (cross section of ordinary cocktail ice, taken under polarized light). Photo: E. Podolsky, 2006; cold laboratory, microscope Nikon Achr 0.90, digital camera Nikon CoolPix 950

The speed of the glacier can range from a few centimeters to more than 10 kilometers per year. So, in 1719, the onset of glaciers in the Alps was so fast that the inhabitants were forced to turn to the authorities with a request to take action and force the “damn beasts” (quote) to go back. Complaints about the glaciers were written to the king by the Norwegian peasants, whose farms were destroyed by the advancing ice. It is known that in 1684 two Norwegian peasants were brought before a local court for non-payment of rent. When asked why they refused to pay, the peasants replied that their summer pastures were covered with advancing ice. The authorities had to make observations to make sure that the glaciers were really advancing - and as a result, we now have historical data on the fluctuations of these glaciers!

The Columbia Glacier in Alaska was considered the fastest glacier on Earth (15 kilometers per year), but more recently, the Jakobshavn Glacier in Greenland came out on top (see a fantastic video of its collapse presented at a recent glaciological conference). The movement of this glacier can be felt by standing on its surface. In 2007, this giant river of ice, 6 kilometers wide and over 300 meters thick, producing about 35 billion tons of the world's tallest icebergs annually, was moving at a speed of 42.5 meters per day (15.5 kilometers per year)!

Pulsating glaciers can move even faster, the sudden movement of which can reach 300 meters per day!

The speed of ice movement within the ice sheet is not the same. Due to friction with the underlying surface, it is minimal near the glacier bed and maximal on the surface. This was measured for the first time after a steel pipe was sunk into a 130-meter-deep hole drilled in the glacier. Measurement of its curvature made it possible to construct a profile of the ice movement velocity.

In addition, the speed of ice in the center of the glacier is higher compared to its marginal parts. The first transverse profile of the uneven distribution of glacier velocities was demonstrated by the Swiss scientist Jean Louis Agassiz in the forties of the 19th century. He left slats on the glacier, putting them in a straight line; a year later, the straight line turned into a parabola, with its apex pointing downstream of the glacier.

As a unique example illustrating the movement of a glacier, the following tragic event can be cited. On August 2, 1947, the plane, which was on a commercial flight from Buenos Aires to Santiago, disappeared without a trace 5 minutes before landing. An intensive search turned up nothing. The secret was revealed only half a century later: on one of the slopes of the Andes, on the peak of Tupungato (Tupungato, 6800 m), in the area of \u200b\u200bthe melting of the glacier, fragments of the fuselage and the bodies of passengers began to melt from the ice. Probably in 1947, due to poor visibility, the plane crashed into a slope, provoked an avalanche and was buried under its deposits in the glacier accumulation zone. It took 50 years for the fragments to go through the full cycle of the glacier matter.

God's plow

The movement of glaciers destroys rocks and transfers a huge amount of mineral material (the so-called moraine) - from broken rock blocks to fine dust.

Median moraine of the Fedchenko Glacier (Pamir, Tajikistan; photo by the author, 2009)

Thanks to the transport of moraine deposits, many surprising finds have been made: for example, fragments of boulders containing inclusions of copper carried by the glacier have been used to find the main deposits of copper ore in Finland. In the United States, in the deposits of terminal moraines (by which one can judge the ancient distribution of glaciers), gold brought by glaciers (Indiana) and even diamonds weighing up to 21 carats (Wisconsin, Michigan, Ohio) were found. This has led many geologists to look north to Canada, where the glacier came from. There, between Lake Superior and Hudson Bay, kimberlite rocks were described - however, scientists could not find kimberlite pipes.

Erratic boulder (a huge block of granite near Lake Como, Italy). From H. T. De la Beche, Sections and Views, Illustrative of Geological Phaenomena (London, 1830)

The very idea that glaciers move was born out of a dispute about the origin of the huge erratic boulders scattered across Europe. This is what geologists call large boulders (“wandering stones”) that are completely different in mineral composition from their surroundings (“a granite boulder on limestone looks to trained eyes as strange as a polar bear on the sidewalk,” one researcher liked to repeat).

One of these boulders (the famous Thunder Stone) became the pedestal for the Bronze Horseman in St. Petersburg. In Sweden, a limestone boulder 850 meters long is known, in Denmark - a giant block of Tertiary and Cretaceous clays and sands 4 kilometers long. In England, in the county of Huntingdonshire, 80 km north of London, an entire village was even built on one of the erratic slabs!

A giant boulder on a leg of ice preserved in the shadows. Unteraar Glacier, Switzerland (Library of Congress; adapted from Bailey, 1982)

"Plowing out" of solid bedrock by a glacier in the Alps can be up to 15 mm per year, in Alaska - 20 mm, which is comparable to river erosion. The erosive, transporting and accumulating activity of glaciers leaves such a colossal imprint on the face of the Earth that Jean-Louis Agassiz called glaciers "God's plow". Many landscapes of the planet are the result of the activity of glaciers, which covered about 30% of the earth's land 20 thousand years ago.

Rocks polished by the glacier; the orientation of the furrows can be used to judge the direction of movement of the past glacier (Pamir, Tajikistan; photo by the author, 2009)

All geologists recognize that it is with the growth, movement and degradation of glaciers that the most complex geomorphological formations on Earth are associated. There are such erosional forms of relief as punishments, similar to the armchairs of giants, and glacial cirques, troughs. There are numerous moraine nunatak landforms and erratic boulders, eskers and fluvioglacial deposits. Fjords are formed, with wall heights up to 1500 meters in Alaska and up to 1800 meters in Greenland and up to 220 kilometers long in Norway or up to 350 kilometers in Greenland (Nordvestfjord Scoresby & Sund East cost). The sheer walls of the fjords have been chosen by base jumpers (see base jumping) all over the world. Crazy height and slope allow you to make long jumps up to 20 seconds of free fall into the void created by glaciers.

Dynamite and glacier thickness

The thickness of a mountain glacier can be tens or even hundreds of meters. The largest mountain glacier in Eurasia - the Fedchenko Glacier in the Pamirs (Tajikistan) - has a length of 77 km and a thickness of more than 900 m.

The Fedchenko Glacier is the largest glacier in Eurasia, 77 km long and almost a kilometer thick (Pamir, Tajikistan; photo by the author, 2009)

The absolute champions are the ice sheets of Greenland and Antarctica. For the first time, the thickness of ice in Greenland was measured during the expedition of the founder of the theory of continental drift, Alfred Wegener, in 1929-30. To do this, dynamite was blown up on the surface of the ice dome and the time required for the echo (elastic vibrations) reflected from the stone bed of the glacier to return to the surface was determined. Knowing the speed of propagation of elastic waves in ice (about 3700 m/s), it is possible to calculate the thickness of the ice.

Today, the main methods for measuring the thickness of glaciers are seismic and radio sounding. It has been determined that the maximum ice depth in Greenland is about 3408 m, in Antarctica 4776 m (Astrolabe subglacial basin)!

Subglacial Lake Vostok

As a result of seismic radar sounding, researchers made one of the last geographical discoveries of the 20th century - the legendary subglacial Lake Vostok.

In absolute darkness, under the pressure of a four-kilometer ice layer, there is a reservoir of water with an area of 17.1 thousand km 2 (almost like Lake Ladoga) and a depth of up to 1500 meters - scientists called this water body Lake Vostok. It owes its existence to its location in a geological fault and geothermal heating, which may support the life of bacteria. Like other water bodies of the Earth, Lake Vostok, under the influence of the gravity of the Moon and the Sun, undergoes ebbs and flows (1–2 cm). For this reason, and because of the difference in depths and temperatures, water is supposed to circulate in the lake.

Similar subglacial lakes have been found in Iceland; in Antarctica, more than 280 such lakes are known today, many of them are connected by subglacial channels. But Lake Vostok is isolated and the largest, which is why it is of the greatest interest to scientists. Oxygen-rich water at a temperature of –2.65°C is at a pressure of around 350 bar.

Location and volume of major Antarctic subglacial lakes (after Smith et al., 2009); the color corresponds to the volume of lakes (km 3), the black gradient indicates the speed of ice movement (m/year)

The assumption of a very high oxygen content (up to 700–1200 mg/l) in lake water is based on the following reasoning: the measured ice density at the firn-to-ice transition boundary is about 700–750 kg/m 3 . This relatively low value is due to the large number of air bubbles. Reaching the lower part of the ice sheet (where the pressure is about 300 bar and any gases "dissolve" in the ice, forming gas hydrates), the density increases to 900–950 kg/m 3 . This means that each specific unit of volume, melting at the bottom, brings at least 15% of the air from each specific unit of surface volume (Zotikov, 2006)

The air is released and dissolved in the water, or possibly collected under pressure in the form of air siphons. This process took place over 15 million years; accordingly, when the lake was formed, a huge amount of air melted out of the ice. There are no analogues of water with such a high oxygen concentration in nature (the maximum in lakes is about 14 mg/l). Therefore, the spectrum of living organisms that could tolerate such extreme conditions is reduced to a very narrow range of oxygenophilic; there is not a single species known to science capable of living in such conditions.

Biologists around the world are extremely interested in obtaining water samples from Lake Vostok, since the analysis of ice cores obtained from a depth of 3667 meters as a result of drilling in the immediate vicinity of Lake Vostok itself showed the complete absence of any microorganisms, and these cores are already of interest to biologists. do not represent. But a technical solution to the issue of opening and penetrating an ecosystem sealed for more than ten million years has not yet been found. The point is not only that now 50 tons of kerosene-based drilling fluid is poured into the well, which prevents the well from being closed by ice pressure and freezing of the drill, but also that any mechanism created by man can upset the biological balance and pollute the water, introducing into it not pre-existing microorganisms.

Perhaps similar subglacial lakes, or even seas, also exist on Jupiter's moon Europa and Saturn's moon Enceladus, under tens or even hundreds of kilometers of ice. It is on these hypothetical seas that astrobiologists place their greatest hopes when searching for extraterrestrial life inside the solar system and are already making plans for how, with the help of nuclear energy (the so-called NASA cryobot), it will be possible to overcome hundreds of kilometers of ice and penetrate into the water space. (Thus, on February 18, 2009, NASA and the European Space Agency ESA officially announced that Europe would be the destination of the next historic mission to explore the solar system, scheduled to arrive in orbit in 2026.)

Glacioisostasia

The colossal volumes of modern ice sheets (Greenland - 2.9 million km 3, Antarctica - 24.7 million km 3) for hundreds and thousands of meters push the lithosphere into the semi-liquid asthenosphere (this is the upper, least viscous part of the earth's mantle). As a result, some parts of Greenland are more than 300 m below sea level, and Antarctica is 2555 m below sea level (Bentley Subglacial Trench)! In fact, the continental beds of Antarctica and Greenland are not single massifs, but huge archipelagos of islands.

After the disappearance of the glacier, the so-called glacioisostatic uplift begins, due to the simple principle of buoyancy described by Archimedes: lighter lithospheric plates slowly rise to the surface. For example, part of Canada or the Scandinavian Peninsula, which were covered by an ice sheet more than 10 thousand years ago, still continues to experience isostatic uplift at a rate of up to 11 mm per year (it is known that even the Eskimos paid attention to this phenomenon and argued about whether whether it is land or whether the sea is sinking). It is assumed that if all the ice in Greenland melts, the island will rise by about 600 meters.

It is difficult to find a habitable area more prone to glacioisostatic uplift than the Replot Skerry Guard Islands in the Gulf of Bothnia. Over the past two hundred years, during which the islands have risen from under the water by about 9 mm per year, the land area has increased here by 35%. The inhabitants of the islands gather once every 50 years and joyfully share new land plots.

Gravity and ice

A few years ago, when I was graduating from university, the question of the mass balance of Antarctica and Greenland in the context of global warming was ambiguous. It was very difficult to determine whether the volume of these giant ice domes is decreasing or increasing. Hypotheses have been put forward that perhaps warming brings more precipitation, and as a result, glaciers are not shrinking, but growing. Data from the GRACE satellites launched by NASA in 2002 clarified the situation and refuted these ideas.

The more mass, the more gravity. Since the surface of the globe is not uniform and includes gigantic mountain ranges, spacious oceans, deserts, etc., the Earth's gravitational field is also not uniform. This gravitational anomaly and its change over time are measured by two satellites - one follows the other and registers the relative deviation of the trajectory when flying over objects of different masses. For example, roughly speaking, when flying over Antarctica, the satellite trajectory will be a little closer to the Earth, and over the ocean, on the contrary, further.

Long-term observations of flybys in the same place make it possible to judge from the change in gravity how the mass has changed. The results showed that the volume of Greenland's glaciers is annually reduced by about 248 km3, and that of Antarctica's glaciers by 152 km3. By the way, according to the maps compiled with the help of GRACE satellites, not only the process of reduction in the volume of glaciers was recorded, but also the above-mentioned process of glacioisostatic uplift of continental plates.

Gravity changes in North America and Greenland from 2003 to 2007, according to GRACE data, due to intense glacier melt in Greenland and Alaska (blue), and glacioisostatic uplift (red) following the melting of the ancient Laurentian ice sheet (by Heki, 2008)

For example, for the central part of Canada, due to glacioisostatic uplift, an increase in mass (or gravity) was recorded, and for neighboring Greenland, a decrease due to the intensive melting of glaciers.

The planetary significance of glaciers

According to academician Kotlyakov, “the development of the geographic environment throughout the Earth is determined by the balance of heat and moisture, which to a large extent depends on the distribution and transformation of ice. The transformation of water from solid to liquid requires a huge amount of energy. At the same time, the transformation of water into ice is accompanied by the release of energy (approximately 35% of the external heat exchange of the Earth).” The spring melting of ice and snow cools the earth, does not allow it to warm up quickly; ice formation in winter - warms, does not allow to cool quickly. If there were no ice, then the temperature differences on Earth would be much greater, the summer heat would be stronger, and the frosts would be more severe.

Taking into account the seasonal snow and ice cover, it can be considered that from 30% to 50% of the Earth's surface is occupied by snow and ice. The most important value of ice for the planet's climate is associated with its high reflectivity - 40% (for snow covering glaciers - 95%), due to which there is a significant cooling of the surface over vast territories. That is, glaciers are not only priceless reserves of fresh water, but also sources of strong cooling of the Earth.

Interesting consequences of the reduction in the mass of glaciation in Greenland and Antarctica were the weakening of the gravitational force that attracts huge masses of ocean water, and a change in the angle of the earth's axis. The first is a simple consequence of the law of gravity: the smaller the mass, the smaller the attraction; the second is that the Greenland ice sheet loads the globe asymmetrically, and this affects the rotation of the Earth: a change in this mass affects the adaptation of the planet to a new mass symmetry, due to which the earth's axis shifts annually (up to 6 cm per year).

The first guess about the gravitational influence of the mass of glaciation on sea level was made by the French mathematician Joseph Alphonse Adhemar, 1797-1862 (he was also the first scientist to point out the connection between ice ages and astronomical factors; after him, the theory was developed by Kroll (see James Croll) and Milankovitch). Adémar tried to estimate the thickness of ice in Antarctica by comparing the depths of the Arctic and Southern oceans. His idea was that the depth of the Southern Ocean is much greater than the depth of the Arctic Ocean due to the strong attraction of water masses by the giant gravitational field of the Antarctic ice cap. According to his calculations, to maintain such a strong difference between the water levels of the north and south, the thickness of the ice cover of Antarctica had to be 90 km.

Today it is clear that all these assumptions are wrong, except that the phenomenon does occur, but with a smaller magnitude - and its effect can extend radially up to 2000 km. The consequences of this effect are that the rise in global sea level due to glacier melt will be uneven (although current models mistakenly assume a uniform distribution). As a result, in some coastal areas, the sea level will rise by 5–30% above the average value (the northeastern part of the Pacific and the southern part of the Indian Ocean), and in some - below (South America, western, southern and eastern coasts of Eurasia) (Mitrovica et al., 2009).

Frozen millennia - a revolution in paleoclimatology

On May 24, 1954, at 4 am, Danish paleoclimatologist Willi Dansgaard was cycling through deserted streets to the central post office with a huge envelope covered with 35 stamps and addressed to the editors of the scientific publication Geochimica et Cosmochimica Acta. The envelope contained the manuscript of the article, which he was in a hurry to publish as soon as possible. He was struck by a fantastic idea that would later make a real revolution in the climate sciences of ancient times and which he would develop all his life.

Willie Dunsgaard with an ice core, Greenland, 1973

(after Dansgaard, 2004)

Dansgaard's research has shown that the amount of heavy isotopes in sediments can be used to determine the temperature at which they were formed. And he thought: what, in fact, prevents us from determining the temperature of past years, simply by taking and analyzing the chemical composition of the water of that time? Nothing! The next logical question is where to get ancient water? In glacial ice! Where can I get ancient glacial ice? In Greenland!

This amazing idea was born a few years before the technology for deep drilling of glaciers was developed. When the technological issue was resolved, an amazing thing happened: scientists discovered an incredible way to travel into the past of the Earth. With every centimeter of ice drilled, their drill blades began to plunge deeper and deeper into paleohistory, revealing ever more ancient secrets of the climate. Each ice core recovered from the well was a time capsule.

Examples of changes in the structure of ice cores with depth, NorthGRIP, Greenland. Size of each section: length 1.65 m, width 8–9 cm. Depths shown (consult source for more information): (a) 1354.65–1356.30 m; (b) 504.80–1506.45 m; (c) 1750.65–1752.30 m; (d) 1836.45–1838.10 m; (e) 2534.40–2536.05 m; (f) 2537.70–2539.35 m; (g) 2651.55–2653.20 m; (h) 2899.05–2900.70 m; (i) 3017.30–3018.95 m (after Svensson et al., 2005)

Having deciphered the cryptography written with hieroglyphs of a whole variety of chemical elements and particles, spores, pollen and bubbles of ancient air hundreds of thousands of years old, one can obtain invaluable information about irrevocably gone millennia, worlds, climates and phenomena.

Time machine 4000 m deep

The age of the oldest Antarctic ice from maximum depths (more than 3500 meters), the search for which is still ongoing, is estimated at about one and a half million years. Chemical analysis of these samples allows us to get an idea of the ancient climate of the Earth, the news of which was brought and preserved in the form of chemical elements by weightless snowflakes that fell from heaven hundreds of thousands of years ago.

This is similar to the story of Baron Munchausen's journey through Russia. During the hunt, somewhere in Siberia, there was a terrible frost, and the baron, trying to call his friends, blew his horn. But to no avail, because the sound froze in the horn and thawed only the next morning in the sun. Approximately the same thing is happening today in the cold laboratories of the world under electron tunneling microscopes and mass spectrometers. Ice cores from Greenland and Antarctica are many kilometers long time machines going back centuries and millennia. The legendary well drilled under the Vostok station (3677 meters) remains the deepest to this day. Thanks to it, for the first time, the relationship between changes in temperature and the content of carbon dioxide in the atmosphere over the past 400 thousand years was shown, and an ultra-long anabiosis of microbes was discovered.

An 800,000-year-old Antarctic ice core from a depth of 3,200 m, Dome Concordia (photo by J. Schwander, University of Bern) © Natural History Museum, Neuchâtel

Detailed paleoreconstructions of air temperature are built on the basis of the analysis of the isotopic composition of the cores - namely, the percentage of the heavy oxygen isotope 18 O (its average content in nature is about 0.2% of all oxygen atoms). Water molecules containing this oxygen isotope evaporate harder and condense more easily. Therefore, for example, in water vapor above the sea surface, the content of 18 O is lower than in sea water. Conversely, water molecules containing 18 O are more likely to participate in condensation on the surface of snow crystals formed in clouds, due to which their content in precipitation is higher than in the water vapor from which precipitation is formed.

The lower the temperature of precipitation formation, the stronger this effect is, that is, the more 18 O in them. Therefore, by estimating the isotopic composition of snow or ice, one can also estimate the temperature at which precipitation was formed.

Mean diurnal variation in temperature (black curve) and 18 O variation in precipitation (grey dots) for one season (2003–1.2004), Dome Fuji, Antarctica (after Fujita and Abe, 2006). 18 O () - deviation of the concentration of the heavy isotopic component of water (H 2 O 18) from the international standard (SMOW) (see Dansgaard, 2004)

And then, using the known altitude temperature profiles, to estimate what the surface air temperature was hundreds of thousands of years ago, when a snowflake just fell on the Antarctic dome to turn into ice, which will be extracted today from a depth of several kilometers during drilling.

Temperature variation relative to today over the past 800 ka from ice cores from Vostok Station and Dome C (EPICA) (after Rapp, 2009)

Annually falling snow carefully preserves on the petals of snowflakes not only information about the air temperature. The number of parameters measured in laboratory analysis is currently enormous. The signals of volcanic eruptions, nuclear tests, the Chernobyl disaster, the content of anthropogenic lead, dust storms, etc. are recorded in tiny ice crystals.

Examples of changes in various paleoclimatic chemical signals in ice with depth (after Dansgaard, 2004). (a) Seasonal fluctuations in 18 O (black indicates the summer season) allowing the dating of cores (section from depths of 405–420 m, Milcent station, Greenland). b) Gray shows specific -radioactivity; the peak after 1962 corresponds to more nuclear tests of this period (surface core section to a depth of 16 m, station Cr te, Greenland, 1974). c) The change in the average acidity of the annual layers makes it possible to judge the volcanic activity of the northern hemisphere, from 550 AD. to the 1960s (st. Cr te, Greenland)

The amount of tritium (3 H) and carbon-14 (14 C) can be used to date the age of the ice. Both of these methods have been elegantly demonstrated on vintage wines - the years on the labels perfectly match the dates read from the analysis. That's just an expensive pleasure, and there is a lot of lime wine for analysis ...

Information about the history of solar activity can be quantified by the content of nitrates (NO 3 –) in glacial ice. Heavy nitrate molecules are formed from NO in the upper atmosphere under the influence of ionizing cosmic radiation (protons from solar flares, galactic radiation) as a result of a chain of transformations of nitrogen oxide (N 2 O) entering the atmosphere from soil, nitrogen fertilizers and fuel combustion products (N 2O + O → 2NO). After formation, the hydrated anion precipitates with precipitation, some of which is eventually buried in the glacier along with the next snowfall.

Isotopes of beryllium-10 (10 Be) make it possible to judge the intensity of deep space cosmic rays bombarding the Earth, and changes in the magnetic field of our planet.

The change in the composition of the atmosphere over the past hundreds of thousands of years was told by small bubbles in the ice, like bottles thrown into the ocean of history, which preserved for us samples of ancient air. They showed that over the past 400 thousand years, the content of carbon dioxide (CO 2) and methane (CH 4) in the atmosphere today is the highest.

Today, laboratories already store thousands of meters of ice cores for future analysis. Only in Greenland and Antarctica (that is, not counting the mountain glaciers), a total of about 30 km of ice cores were drilled and extracted!

Ice age theory

The beginning of modern glaciology was laid by the theory of ice ages that appeared in the first half of the 19th century. The idea that in the past glaciers extended hundreds and thousands of kilometers to the south seemed unthinkable before. As one of the first glaciologists of Russia, Peter Kropotkin (yes, the same one), wrote, “at that time, belief in the ice cover that reached Europe was considered an unacceptable heresy ...”.

Jean Louis Agassiz, pioneer of glaciological research. C. F. Iguel, 1887, marble.

The founder and main defender of the glacial theory was Jean Louis Agassiz. In 1839 he wrote: “The development of these huge ice sheets must have led to the destruction of all organic life on the surface. The lands of Europe, once covered with tropical vegetation and inhabited by herds of elephants, hippos and giant carnivores, were buried under the overgrown ice covering the plains, lakes, seas and mountain plateaus.<...>Only the silence of death remained... The springs dried up, the rivers froze, and the rays of the sun rising over the frozen shores... met only the whisper of northern winds and the rumble of cracks opening in the middle of the surface of a giant ocean of ice.

Most of the geologists of that time, little familiar with Switzerland and the mountains, ignored the theory and were not even able to believe in the plasticity of ice, let alone imagine the thickness of the glacial strata described by Agassiz. This continued until the first scientific expedition to Greenland (1853–55), led by Elisha Kent Kane, reported a complete glaciation of the island (“an ocean of ice of infinite size”).

The recognition of the theory of ice ages had an incredible impact on the development of modern natural science. The next key issue was the reason for the change of ice ages and interglacials. At the beginning of the 20th century, the Serbian mathematician and engineer Milutin Milankovic developed a mathematical theory describing the dependence of climate change on changes in the orbital parameters of the planet, and devoted all his time to calculations to prove the validity of his theory, namely, to determine the cyclic change in the amount of solar radiation entering the Earth (so called insolation). The Earth, spinning in the void, is in a gravitational web of complex interaction between all objects in the solar system. As a result of orbital cyclical changes (eccentricity of the Earth's orbit, precession and nutation of the Earth's axis inclination), the amount of solar energy entering the Earth changes. Milankovitch found the following cycles: 100 thousand years, 41 thousand years and 21 thousand years.

Unfortunately, the scientist himself did not live to see the day when his insight was elegantly and flawlessly proven by paleo-oceanographer John Imbrie. Imbri assessed past temperature changes by examining cores from the bottom of the Indian Ocean. The analysis was based on the following phenomenon: different types of plankton prefer different, strictly defined temperatures. Every year, the skeletons of these organisms settle on the ocean floor. By lifting this layered cake from the bottom and identifying the species, one can judge how the temperature has changed. The paleotemperature variations determined in this way surprisingly coincided with the Milankovitch cycles.

Today it is known that cold glacial eras were followed by warm interglacials. Complete glaciation of the globe (according to the so-called "snowball" theory) presumably took place 800-630 million years ago. The last glaciation of the Quaternary period ended 10 thousand years ago.

The ice domes of Antarctica and Greenland are relics of past glaciations; having disappeared now, they will not be able to recover. During periods of glaciation, continental ice sheets covered up to 30% of the earth's land mass. So, 150 thousand years ago, the thickness of glacial ice over Moscow was about a kilometer, and over Canada - about 4 km!

The era in which human civilization now lives and develops is called the Ice Age, the interglacial period. According to calculations made on the basis of Milankovitch's orbital theory of climate, the next glaciation will come in 20,000 years. But the question remains whether the orbital factor can overpower the anthropogenic one. The fact is that without the natural greenhouse effect, our planet would have an average temperature of -6°C, instead of today's +15°C. That is, the difference is 21°C. The greenhouse effect has always existed, but human activity greatly enhances this effect. Now the content of carbon dioxide in the atmosphere is the highest in the last 800 thousand years - 0.038% (whereas the previous maximums did not exceed 0.03%).

Today, glaciers almost all over the world (with some exceptions) are rapidly shrinking; the same goes for sea ice, permafrost and snow cover. It is estimated that half of the world's mountain glaciation will disappear by 2100. About 1.5-2 billion people living in various countries of Asia, Europe and America may face the fact that the rivers fed by the melt waters of glaciers will dry up. At the same time, rising sea levels will rob people of their land in the Pacific and Indian Oceans, the Caribbean and Europe.

Wrath of the Titans - glacial catastrophes

Increasing anthropogenic impact on the planet's climate can increase the likelihood of natural disasters associated with glaciers. Masses of ice have gigantic potential energy, the realization of which can have monstrous consequences. Some time ago, a video of the collapse of a small column of ice into the water and the subsequent wave that washed away a group of tourists from nearby rocks circulated on the Internet. In Greenland, similar waves 30 meters high and 300 meters long were observed.

Glacial catastrophe in North Ossetia September 20, 2002, was recorded on all seismometers in the Caucasus. The collapse of the Kolka glacier provoked a giant glacier collapse - 100 million m 3 of ice, stones and water swept through the Karmadon Gorge at a speed of 180 km per hour. Mudflow splashes tore loose deposits of the sides of the valley in places up to 140 meters high. 125 people died.

One of the worst glacial disasters in the world was the collapse of the northern slope of Mount Huascaran in Peru in 1970. An earthquake of magnitude 7.7 triggered an avalanche of millions of tons of snow, ice and rocks (50 million m3). The collapse stopped only after 16 kilometers; two cities, buried under the rubble, turned into a mass grave for 20 thousand people.

Trajectories of ice avalanches Nevados Huascarán 1962 and 1970, Peru

(according to UNEP's DEWA/GRID-Europe, Geneva, Switzerland)

Another type of glacier hazard is the outburst of dammed glacial lakes that occur between a melting glacier and a terminating moraine. The height of the terminal moraines can reach 100 m, creating a huge potential for the formation of lakes and their subsequent outburst.

Potentially dangerous moraine-dammed periglacial lake Tsho Rolpa in Nepal, 1994 (volume: 76.6 million m 3 , area: 1.5 km 2 , moraine height: 120

Potentially hazardous moraine-dammed periglacial lake Tsho Rolpa in Nepal, 1994 (volume: 76.6 million m 3 , area: 1.5 km 2 , moraine bar height: 120 m). Photo is the courtesy by N. Takeuchi, Graduate School of Science, Chiba University

The most monstrous glacial lake outburst occurred across the Hudson Strait into the Labrador Sea about 12,900 years ago. The outburst of Lake Agassiz, which was larger than the Caspian Sea, caused an abnormally rapid (over 10 years) cooling of the North Atlantic climate (by 5 ° C in England), known as the Early Dryas (see Younger Dryas) and discovered during the analysis of Greenland ice cores. A huge amount of fresh water disrupted the thermohaline circulation Atlantic Ocean, which blocked the transfer of heat by the current from low latitudes. Today, such a spasmodic process is feared in connection with global warming, which is desalinating the waters of the North Atlantic.

Today, due to the accelerated melting of the world's glaciers, the size of dammed lakes is increasing and, accordingly, the risk of their breakthrough is growing.

Growth in the area of glacial dammed lakes on the northern (left) and southern (right) slopes of the Himalayan Range (according to Komori, 2008)

In the Himalayas alone, 95% of whose glaciers are rapidly melting, there are about 340 potentially dangerous lakes. In 1994, in Bhutan, 10 million cubic meters of water, pouring out of one of these lakes, traveled 80 kilometers at great speed, killing 21 people.

According to forecasts, the outburst of glacial lakes could become an annual disaster. Millions of people in Pakistan, India, Nepal, Bhutan and Tibet will not only face the inevitable reduction of water resources due to the disappearance of glaciers, but will also face the deadly danger of outburst lakes. Hydroelectric power plants, villages, infrastructure can be destroyed in an instant by terrible mudflows.

A series of images showing the intensive retreat of the Nepalese AX010 glacier, Shürong region (27°42"N, 86°34"E). (a) 30 May 1978, (b) 2 Nov. 1989, (c) 27 Oct. 1998, (d) 21 Aug. 2004 (Photos by Y. Ageta, T. Kadota, K. Fujita, T. Aoki are the courtesy of the Cryosphere Research Laboratory, Graduate School of Environmental Studies, Nagoya University)

Another type of glacial catastrophe is lahars, resulting from volcanic eruptions covered with ice caps. The meeting of ice and lava gives rise to gigantic volcanic mudflows, typical of the land of "fire and ice" Iceland, Kamchatka, Alaska, and even on Elbrus. Lahars can reach monstrous sizes, being the largest among all types of mudflows: they can be up to 300 km long and 500 million m 3 in volume.

On the night of November 13, 1985, the inhabitants of the Colombian city of Armero (Armero) woke up from a crazy noise: a volcanic mudflow swept through their city, washing away all the houses and structures in its path - its bubbling slurry claimed the lives of 30 thousand people. Another tragic event occurred on a fateful Christmas evening in 1953 in New Zealand - a lake outburst from an icy volcano crater provoked a lahar, which washed away the railway bridge just in front of the train. The locomotive and five cars with 151 passengers dived and disappeared forever in the rushing stream.

In addition, volcanoes can simply destroy glaciers - for example, the monstrous eruption of the North American volcano Saint Helens (Saint Helens) demolished 400 meters of the mountain along with 70% of the volume of glaciers.

people of ice

The harsh conditions in which glaciologists have to work are perhaps one of the most difficult that modern scientists have to face. Most of the field observations involve working in cold hard-to-reach and remote parts of the globe, with harsh solar radiation and insufficient oxygen. In addition, glaciology often combines mountaineering with science, thus making the profession deadly.

Base camp of the expedition to the Fedchenko glacier, Pamir; altitude approximately 5000 m above sea level; about 900 m of ice under tents (author's photo, 2009)

Frostbite is familiar to many glaciologists, because of which, for example, a former professor of my institute had his fingers and toes amputated. Even in a comfortable laboratory, temperatures can drop to -50°C. In the polar regions, all-terrain vehicles and snowmobiles sometimes fall into 30-40-meter cracks, the most severe snowstorms often make the high-altitude workdays of researchers a real hell and claim more than one life every year. This is a job for strong and hardy people who are sincerely dedicated to their work and the endless beauty of the mountains and poles.

Literature:

Adhemar J. A., 1842. Revolutions of the Sea. Deluges Periodiques, Paris.
Bailey R.H., 1982. Glacier. Planet earth. Time-Life Books, Alexandria, Virginia, USA, 176 p.
Clark S., 2007. The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began. Princeton University Press, 224 p.
Dansgaard W., 2004. Frozen Annals - Greenland Ice Sheet Research. The Niels Bohr Institute, University of Copenhagen, 124 p.
EPICA community members, 2004. Eight glacial cycles from an Antarctic ice core. Nature, 429 (10 June 2004), 623–628.
Fujita, K., and O. Abe. 2006. Stable isotopes in daily precipitation at Dome Fuji, East Antarctica, Geophys. Res. Lett., 33, L18503, doi:10.1029/2006GL026936.
GRACE (the Gravity Recovery and Climate Experiment).
Hambrey M. and Alean J., 2004, Glaciers (2nd edition), Cambridge University Press, UK, 376 p.
Heki, K. 2008. Changing earth as shown by gravity (PDF, 221 Kb). Littera Populi - Hokkaido University's public relations magazine, June 2008, 34, 26–27.
Glacial pace picks up // In the Field (The Nature reporters" blog from conferences and events).
Imbrie J., and Imbrie K. P., 1986. Ice Ages: Solving the Mystery. Cambridge, Harvard University Press, 224 p.
IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change . Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 p.
Kaufman S. and Libby W. L., 1954. The Natural Distribution of Tritium // Physical Review, 93, no. 6, (March 15, 1954), p. 1337–1344.
Komori, J. 2008. Recent expansions of glacial lakes in the Bhutan Himalayas. Quaternary International, 184, 177–186.
Lynas M., 2008. Six Degrees: Our Future on a Hotter Planet // National Geographic, 336 p.
Mitrovica, J. X., Gomez, N. and P. U. Clark, 2009. The Sea-Level Fingerprint of West Antarctic Collapse // Science. Vol. 323. No. 5915 (6 February 2009) p. 753. DOI: 10.1126/science.1166510.
Pfeffer W. T., Harper J. T., O’Neel S., 2008. Kinematic constraints on glacier contributions to 21st-century sea level rise. Science, 321 (5 September 2008), p. 1340–1343.
Prockter L.M., 2005. Ice in the Solar System. Johns Hopkins APL Technical Digest. Volume 26. Number 2 (2005), p. 175–178.
Rampino M. R., Self S., Fairbridge R. W., 1979. Can rapid climatic change cause volcanic eruptions? // Science, 206 (November 16, 1979), no. 4420, p. 826–829.
Rapp, D. 2009. Ice Ages and Interglacials. Measures, Interpretation and Models. Springer, UK, 263 p.
Svensson, A., S. W. Nielsen, S. Kipfstuhl, S. J. Johnsen, J. P. Steffensen, M. Bigler, U. Ruth, and R. Röthlisberger. 2005. Visual stratigraphy of the North Greenland Ice Core Project (NorthGRIP) ice core during the last glacial period, J. Geophys. Res., 110, D02108, doi:10.1029/2004JD005134.
Velicogna I. and Wahr J., 2006. Acceleration of Greenland ice mass loss in spring 2004 // Nature, 443 (21 September 2006), p. 329–331.
Velicogna I. and Wahr J., 2006. Measurements of time-variable gravity show mass loss in Antarctica // Science, 311 (24 March 2006), no. 5768, p. 1754–1756
Zotikov I. A., 2006. The Antarctic Subglacial Lake Vostok. Glaciology, Biology and Planetology. Springer-Verlag, Berlin, Heidelberg, New York, 144 p.
Voitkovsky K.F., 1999. Fundamentals of glaciology. Nauka, Moscow, 255 p.
Glaciological dictionary. Ed. V. M. Kotlyakova. L., GIMIZ, 1984, 528 p.
Zhigarev V. A., 1997. Oceanic permafrost. Moscow, Moscow State University, 318 p.
Kalesnik S. V., 1963. Essays on glaciology. State publishing house of geographical literature, Moscow, 551 p.
Kechina K. I., 2004. The valley that has become an icy grave // BBC. Photo report: September 21, 2004.
Kotlyakov V. M., 1968. Snow Cover of the Earth and Glaciers. L., GIMIZ, 1968, 480 p.
Podolsky E. A., 2008. An unexpected angle. Jean Louis Rodolphe Agassiz, The Elements, March 14, 2008 (21 pp., revised version).
Popov A.I., Rosenbaum G.E., Tumel N.V., 1985. Cryolithology. Moscow University Press, 239 p.

Ecology

Many of these natural wonders can only be seen by scientists, as they are located in cold, sparsely populated areas of our planet.

Here 10 most beautiful ice formations nature from glaciers, frozen waterfalls to ice caves and icebergs.

1. Blue River, Greenland Glaciers

This amazing blue river was formed by melting Peterman Glacier in Greenland, which filled low-lying areas with blue water. Places filled with water change seasonally, which each time modifies the shape of the river. The bright blue color was formed from glacial silt.

2. Glacial waterfalls, Svalbard archipelago (Svalbard)

Svalbard, or as it is also called Svalbard, is archipelago in the arctic located in the northern part of the kingdom of Norway. Despite being close to the North Pole, Svalbard is relatively warm due to the influence of the Gulf Stream. This is a large area of islands, which 60 percent covered by glaciers.

Some of these glaciers form small waterfalls from the melting of snow and ice, which can be seen during the warmer months. Huge Brosvelbrin Glacier located on the second largest island - the North-East Land with a length of 200 km is covered with hundreds of such melting waterfalls.

3. Ice cave, Iceland

This amazing cave Svínafellsjökull lagoon in Iceland was created by the ice cap of a volcano Vatnajökull in the national park Skaftafel. The beautiful blue color was formed as a result of the fact that over the course of many centuries the ice was compacted, squeezing out all the air. Due to the lack of air in the ice, it absorbs a lot of light and the cave has a unique texture and color.

The safest visit the ice cave in winter and for better visibility - after the rainy season. Many of those who were lucky enough to be inside the cave heard cracking sounds. However, these sounds are not due to the fact that the glacier can collapse, but because it is constantly moving.

4. Briksdalsbreen Glacier, Norway

Briksdalsbreen- one of the most famous Jostedalsbreen arm glaciers- the largest glacier located in Norway.

It ends with a small glacial lake located 346 meters above sea level.

Tourists from all over the world come to admire the Briksdalsbreen glacier, located among waterfalls and high mountains.

5. Ice Canyon, Greenland

This Ice Canyon in Greenland 45 meters deep was created by melt water as a result of global warming. Along the edge of the canyon, lines can be seen that show layers of ice and snow that have formed over the years.

Dark deposits at the bottom of this channel are cryoconite, silty material resulting from weathering. It is deposited on snow, glaciers and ice caps.

6. Elephant's Paw Glacier, Greenland

This huge glacier called "Elephant's Paw" is located in the northern part of Greenland. The gray area at the bottom of the glacier is the melting zone, which was formed from the melt water of the channels. The almost perfect round shape of the glacier has diameter about 5 kilometers.

7. Frozen wave, ice floes of Antarctica

Although at first glance it may seem that in front of you is a huge wave that has frozen, it was not formed from a wave of water.

Actually this blue ice, which is formed when compressed air bubbles are expelled. Ice appears blue because when light passes through its thick layer, blue light is reflected and red light is absorbed.

The ice itself formed over time, and repeated melting and freezing gave the formation a smooth appearance.

8. Striped icebergs, Southern Ocean

This phenomenon is most commonly seen in the Southern Ocean. Striped icebergs may have blue, green and brown stripes and are formed when large chunks of ice break off ice shelves and fall into the ocean.

So, for example, blue stripes formed when the ice sheet filled with melt water and froze so quickly that bubbles did not have time to form. Salty sea water containing algae can lead to green streaks. Other colors usually appear when precipitation is picked up by a sheet of ice as it falls into the water.

9. Ice Towers of Mount Erebus, Antarctica

The ever-active Mount Erebus is perhaps the only place in Antarctica where ice and fire meet. Here at an altitude of 3800 meters you can find hundreds ice towers reaching up to 20 meters in height. Often they emit steam, some of which freezes inside the towers, expanding and lengthening it.

10. Frozen waterfall

So, for example, the Fang waterfall in the city of Vail in the USA turns into a huge ice pillar in especially cold winters, reaching 50 meters high and 8 meters wide.

The Day Niagara Falls Frozen

During prolonged winter frosts, some parts of the waterfall may form a crust of ice. A few years ago, photographs appeared on the Internet that captured frozen Niagara Falls made presumably in 1911.

In fact, the photographs were most likely taken in March 1848, when water flow stopped due to ice blockage for a few hours. The entire waterfall did not freeze completely, and some streams of water did break through. Niagara Falls froze over for the second time in history in 1936 due to severe frosts.

11. "Penitent Snows", Andes Mountains

Kalgaspory or as they are also called "penitent snows" or "penitent monks" - these are amazing ice spikes that form on the plains in the highlands, for example, in the Andes mountains, which are located at an altitude of 4000 meters above sea level.

Calgaspores can reach a height from a few centimeters, resembling frozen grass, and up to 5 meters, giving the impression of an ice forest.

It is believed that they were formed due to strong winds in the area and sunlight, which causes uneven ice melting and leads to the appearance of strange shapes.

12. Kungur Ice Cave, Russia

Kungur ice cave one of the largest caves in the world and the most amazing wonders of the Urals, which is located on the outskirts of the city of Kungur in the Perm region. The cave is believed to be over 10,000 years old.

Her total length reaches 5700 meters, inside the cave 48 grottoes and 70 underground lakes up to 2 meters deep. The temperature inside the ice cave varies from -10 to -2 degrees Celsius.

The Kungur Ice Cave has gained popularity among tourists due to its ice formations, stalactites, stalagmites, ice crystals and ice columns. The most famous grottoes: Brilliant, Polar, Meteor, Giant, Ruins, Cross.

Moscow often hosts various events where you can see ice sculptures. Whatever they are called: and ice sculpture exhibitions, and ice sculpture festivals, ice sculpture competitions, in various ways. Such exhibitions-competitions always attract many visitors. Both adults and, most of all, probably, children are interested in seeing, examining, examining various plots embodied in ice. The flight of fancy among the creators of ice sculpture is wide, and artistic abilities are high level, therefore, sometimes real masterpieces are cut out of ice, with which it is a pity to part with them later in the spring. At least put it in the fridge!

Ice sculpture festivals are held annually in many Moscow parks. On some you can not only see ice sculptures, but also see how they are created, and, perhaps, even learn how to make them. Master classes are held for those who wish.

But there are places where you can see ice sculptures not only in winter, but all year round. In the park on Krasnaya Presnya is ice sculpture exhibition, which is open to visitors both in the cold and warm seasons. A constant temperature of -10°C is maintained here, thanks to which the ice does not melt and all the sculptures are preserved in the form in which they were created.

The Ice Sculpture Gallery is located at the Vystavochnaya metro station. The address- st. Mantulinskaya, 5. I have never been to Vystavochnaya, and I must say, this is a rather interesting station. Leaving the metro, we get to the embankment of the Moskva River with a view of one of the Stalin skyscrapers and the building of the Government of the Russian Federation. The weather was cloudy, the photo also turned out to be sad. On the right is a bridge across the river, not an ordinary one, but some kind of trade one. The skyscrapers of Moscow City are right there. I did not take a picture, because it started to rain, did not get the SLR. But there is a desire to come here in the summer, take a walk along the embankment. It is a pity that they do not depart from here, although there seems to be a pier. Maybe someone local, write in the comments, river buses go from here?

From the metro to the exhibition of ice sculptures, walk a maximum of 10 minutes, along the embankment, past the Expo Center and the tennis court (see the map above). We go into the park, there are signs where to go, but because in the park we see only one building, suitable in size, it is already clear where the gallery is located.

On Krasnaya Presnya, the Ice Sculpture Museum is open daily from 11:00 to 20:00. Ticket price for adults - 350 rubles; for schoolchildren, students, pensioners - 250 rubles; for children - 50 rubles; this is not as common as one would like. But on the other hand, there is a suspicion that its cost is simply included in the ticket price)).

On Saturdays at 12:00 pm, the gallery also hosts a free ice sculpture workshop. I managed to shoot it, the sound, however, is not very good, I still shot it with a camera, and not with a video camera. And the video weighs 2 gigabytes, so if anyone has a slow Internet - sorry, it will take a long time to load.

Some photos from the master class.

How to do it, you say?

Haa, now I'll make you a flower!

Finally, we go into the room itself with ice sculptures.

The ice sculptures in the gallery are based on Russian fairy tales. To my shame, I realized that I didn’t recognize some plots and didn’t remember the names of fairy tales. It's good that a family with children came along with us, and my grandmother told her grandchildren, and for one thing, me, who is who and where.

A squirrel gnawing precious nuts and servants guarding it from the tale of Tsar Saltan. The pink color in the photo is a special highlight. Since all the ice sculptures in the Gallery are transparent, the lighting adds to the effect.

The Little Humpbacked Horse, the Firebird and Ivan Tsarevich.

The crow and the fox from Krylov's fable. The fox, in my opinion, looks more like a marten. Only in the photo I noticed that it was broken in two places and glued together.

Nightingale the robber.

Baba Yaga on a stupa. Her head is way too big.

Emelya and pike.

Serpent Gorynych and ... I don’t remember who fought with him, but Gorynych had already knocked out his teeth, judging by the photograph.

The plot from the fairy tale "Ivan Tsarevich and the Gray Wolf".

A hut with a snack for a rainy day.

This is probably the swan princess.

Mosquito, straight jewelry work.

After 10 minutes, my friend could not stand the cold, despite the fact that we were in autumn clothes, and ran away from the gallery. I alone examined and photographed the sculptures. Accidentally found a grandmother with a broken trough. She was so small that hardly anyone paid attention to her.

The Golden Cockerel. I didn't see him right away either.

Traditionally, snow fun is held where winters are long and harsh, and ice and snow are plentiful - for example, in Norway or Canada. However, the festivals in Harbin (China) and Sapporo (Japan) are among the largest in the world.

China, Harbin, International Snow and Ice Festival

This event has been held annually since 1963. There were breaks in its history, but since 1985 the festival has been renewed and now annually welcomes guests from all over the world. There are always many tourists here, for whom an extensive program is provided, including skiing and snowmobiling, and even swimming in the hole.

Ice for sculptures is brought from the Songhua River, there is also enough snow in Northeast China, where Harbin is located - winters are harsh here, the thermometer can periodically drop below -30 degrees.

It is especially beautiful on the territory of the festival at night, when multi-colored illumination lights transform ice sculptures, painting them with bright colors.

The official start of the festival is January 5, and it lasts exactly one month. But of course, the fantastic creations of the masters do not appear on its sites by magic on the eve of the opening - this is a long process that sometimes does not stop even at night. And in fact, the scope of the festival is noticeably wider: some works can be seen even before the official opening, and even after the end of the program, many buildings are preserved as long as the weather permits.

Japan, Sapporo, Snow Festival

The history of this festival begins in 1950, but world fame came to him more than 20 years later - after the XI Winter Olympic Games, which were held in Sapporo in 1972. Since 1974, the International Snow Figure Competition has been held here every year, in which teams from around the world participate.

The Japanese festival is held in early February and lasts only one week, but this does not prevent its participants from creating grandiose snow monuments. Just take a look at the next photo - impressive, isn't it?

Festival events in Sapporo take place at several venues. From the snow kingdom in Odori Park, let's move on to an ice fairy tale, located in the Susukino quarter.

Amazing ice figures not only decorate the city, but also attract many tourists who come to the Sapporo Snow Festival every year.

The third site of the festival is the Tsudomu Stadium, where craftsmen create snow copies of world architecture monuments. Real size.

The Sapporo Snow Festival has a competitor: the second largest city in Hokkaido - Asahikawa holds its own winter festival every year at the same time. It is difficult to surprise the participants of such events with giant snow compositions, but it was at the festival in Asahikawa that the Guinness record for the largest snow sculpture was registered.

In search of "zest" organizers Asahikawa Winter Festival decided to bet on an unusual illumination - and did not lose. No wonder this event is now also called the festival of light.

Japan, Asahikawa, February 9, 2013. Fairy Spring - ice sculpture with illumination. Photo courtesy of iStock.com/seiksoon

Masterfully executed ice compositions are attractive in and of themselves - and talentedly selected lighting creates real magic.

Canada, Ottawa, Winterlude

They love lighting effects in Canada too. To see this, just look at the photographs taken in Ottawa at the Winterlude festival (Winterlude = winter (winter) + interlude (interlude, interlude - “interaction”)).

This holiday is relatively young - it has been held every February since 1979. The main events are usually timed to the weekend, but you can admire the creations of the contestants on weekdays. The only thing that can spoil the festive atmosphere is unstable weather: thaws are not uncommon in Ottawa.

Unlike festivals in China and Japan, here the international snow and ice sculpture competition is only part of a very extensive and varied program of events, including, among other things, such exotic fun as “races of waiters” and “races on beds” that take place on the lake Dow. However, the ice figures do not become less beautiful or less amazing.

Winterlude is not the only ice and snow sculpture festival in Canada. AT Toronto takes place every February weekend icefest, and in Quebec tourists come every winter winter carnival. Here, on the occasion of events, a large Ice Palace is built and even a hotel is built from ice and snow.

The holiday in Quebec has been held annually since 1955 and lasts more than two weeks - from January 31 to February 16. Well, for the first time such an event took place here already in 1894. Its program is also very extensive and includes not only an ice sculpture competition, but also numerous sports competitions, concerts, sleigh rides and other winter entertainment.

What to see around rimini

Interesting objects and stories

Gallery of ice sculptures on Krasnaya Presnya (closed). Festivals of snow and ice sculptures in different countries Blue River, Greenland glaciers