How polar explorers use the properties of ice. Why does ice float in water? Density of ice and water

Polar ice blocks and icebergs drift in the ocean, and even in drinks the ice never sinks to the bottom. We can conclude that ice does not sink in water. Why? If you think about it, this question may seem a little strange, because ice is solid and - intuitively - should be heavier than liquid. Although this statement is true for most substances, water is an exception to the rule. What distinguishes water and ice are hydrogen bonds, which make ice lighter in its solid state than when it is in its liquid state.

Scientific question: why does ice not sink in water?

Let's imagine that we are in a lesson called " The world"in 3rd grade. “Why doesn’t ice sink in water?” the teacher asks the children. And kids, without deep knowledge of physics, begin to reason. “Perhaps this is magic?” - says one of the children.

Indeed, the ice is extremely unusual. There are practically no other natural substances that, in a solid state, could float on the surface of a liquid. This is one of the properties that makes water such an unusual substance and, frankly, it is what changes the path of planetary evolution.

There are some planets that contain huge amounts of liquid hydrocarbons such as ammonia - however, when this material freezes, it sinks to the bottom. The reason why ice does not sink in water is that when water freezes, it expands, and at the same time its density decreases. Interestingly, the expansion of ice can break the stones - the process of glaciation of water is so unusual.

Speaking scientific language, during the freezing process, rapid weathering cycles and certain chemical substances, released on the surface are capable of dissolving minerals. In general, the freezing of water is associated with the following processes and possibilities: physical properties no other liquids are suggested.

Density of ice and water

Thus, the answer to the question of why ice does not sink in water but floats on the surface is that it has a lower density than liquid - but this is a first-level answer. To better understand, you need to know why ice has low density, why things float in the first place, and how density causes float.

Let's remember the Greek genius Archimedes, who found out that after immersing a certain object in water, the volume of water increases by a number equal to the volume of the immersed object. In other words, if you place a deep dish on the surface of water and then place a heavy object in it, the volume of water that pours into the dish will be exactly equal to the volume of the object. It does not matter whether the object is fully or partially immersed.

Properties of water

Water is amazing substance, which mainly nourishes life on earth, because every living organism needs it. One of the most important properties of water is that it is at its highest density at 4°C. Thus, hot water or ice is less dense than cold water. Less dense substances float on top of denser substances.

For example, when preparing a salad, you may notice that the oil is on the surface of the vinegar - this can be explained by the fact that it has a lower density. The same law is also valid to explain why ice does not sink in water, but does sink in gasoline and kerosene. It’s just that these two substances have a lower density than ice. So, if you throw an inflatable ball into a pool, it will float on the surface, but if you throw a stone into the water, it will sink to the bottom.

What changes happen to water when it freezes?

The reason why ice does not sink in water is due to hydrogen bonds, which change when water freezes. As you know, water consists of one oxygen atom and two hydrogen atoms. They are attached covalent bonds, which are incredibly strong. However, another type of bond that forms between different molecules, called a hydrogen bond, is weaker. These bonds form because positively charged hydrogen atoms are attracted to the negatively charged oxygen atoms of neighboring water molecules.

When the water is warm, the molecules are very active, move around a lot, and quickly form and break bonds with other water molecules. They have the energy to get closer to each other and move quickly. So why doesn't ice sink in water? Chemistry hides the answer.

Physico-chemistry of ice

As the water temperature drops below 4°C, the kinetic energy of the liquid decreases, so the molecules no longer move. They do not have the energy to move and break and form bonds as easily as at high temperatures. Instead, they form more hydrogen bonds with other water molecules to form hexagonal lattice structures.

They form these structures to keep the negatively charged oxygen molecules away from each other. In the middle of the hexagons formed as a result of the activity of molecules, there is a lot of emptiness.

Ice sinks in water - reasons

Ice is actually 9% less dense than liquid water. Therefore, ice takes up more space than water. Practically, this makes sense because ice expands. This is why it is not recommended to freeze a glass bottle of water - frozen water can create large cracks even in concrete. If you have a liter bottle of ice and a liter bottle of water, then the ice water bottle will be lighter. The molecules are further apart at this point than when the substance is in a liquid state. This is why ice does not sink in water.

As ice melts, the stable crystalline structure breaks down and becomes denser. When water warms up to 4°C, it gains energy and the molecules move faster and further. This is why hot water takes up more space than cold water and floats on top of cold water - it is less dense. Remember, when you are on a lake, while swimming, the top layer of water is always pleasant and warm, but when you put your feet deeper, you feel the cold of the lower layer.

The importance of the process in the functioning of the planet

Despite the fact that the question “Why doesn’t ice sink in water?” for grade 3, it is very important to understand why this process occurs and what it means for the planet. Thus, the buoyancy of ice has important consequences for life on Earth. in winter in cold places - this allows fish and other aquatic animals to survive under the ice blanket. If the bottom were frozen, there is a high probability that the entire lake could be frozen.

Under such conditions, not a single organism would remain alive.

If the density of ice were higher than the density of water, then the ice in the oceans would sink, and the ice caps, which in this case would be at the bottom, would not allow anyone to live there. The bottom of the ocean would be full of ice - and what would it all turn into? Among other things, polar ice is important because it reflects light and prevents planet Earth from overheating.

Everyone knows that ice is frozen water, or rather, it is in a solid state of aggregation. But Why does ice not sink in water, but float on its surface?

Water is an unusual substance with rare, even anomalous properties. In nature, most substances expand when heated and contract when cooled. For example, mercury in a thermometer rises through a narrow tube and shows an increase in temperature. Because mercury freezes at -39ºC, it is not suitable for thermometers used in harsh temperature environments.

Water also expands when heated and contracts when cooled. However, in the cooling range from approximately +4 ºC to 0 ºC it expands. This is why water pipes can burst in winter if the water in them has frozen and large masses of ice have formed. The ice pressure on the pipe walls is enough to cause them to burst.

Water expansion

Since water expands when cooled, the density of ice (i.e. its solid form) is less than that of liquid water. In other words, a given volume of ice weighs less than the same volume of water. This is reflected by the formula m = ρV, where V is the volume of the body, m is the mass of the body, ρ is the density of the substance. There is an inversely proportional relationship between density and volume (V = m/ρ), i.e., with increasing volume (as water cools), the same mass will have a lower density. This property of water leads to the formation of ice on the surface of reservoirs - ponds and lakes.

Let's assume that the density of water is 1. Then the ice will have a density of 0.91. Thanks to this figure, we can find out the thickness of the ice floe that floats on the water. For example, if an ice floe has a height above water of 2 cm, then we can conclude that its underwater layer is 9 times thicker (i.e. 18 cm), and the thickness of the entire ice floe is 20 cm.

In the area of ​​the North and South Poles of the Earth, water freezes and forms icebergs. Some of these floating ice mountains are enormous. The largest of known to man an iceberg with a surface area of ​​31,000 square meters is considered. kilometers, which was discovered in 1956 in the Pacific Ocean.

How does water solid state increases its volume? By changing its structure. Scientists have proven that ice has an openwork structure with cavities and voids, which, when melted, are filled with water molecules.

Experience shows that the freezing point of water decreases with increasing pressure by approximately one degree for every 130 atmospheres.

It is known that in the oceans at great depths the water temperature is below 0 ºС, and yet it does not freeze. This is explained by the pressure created by the upper layers of water. A layer of water one kilometer thick presses with a force of about 100 atmospheres.

Comparison of the densities of water and ice

Can the density of water be less than the density of ice and does this mean that he will drown in it? Answer to this question affirmative, which is easy to prove with the following experiment.

Let's take from the freezer, where the temperature is -5 ºС, a piece of ice the size of a third of a glass or a little more. Let's put it in a bucket of water at a temperature of +20 ºС. What are we observing? The ice quickly sinks and sinks, gradually beginning to melt. This happens because water at a temperature of +20 ºС has a lower density compared to ice at a temperature of -5 ºС.

There are modifications of ice (at high temperatures and pressures), which, due to their greater density, will sink in water. We are talking about the so-called “heavy” ice - deuterium and tritium (saturated with heavy and superheavy hydrogen). Despite the presence of the same voids as in protium ice, it will sink in water. In contrast to “heavy” ice, protium ice is devoid of heavy hydrogen isotopes and contains 16 milligrams of calcium per liter of liquid. The process of its preparation involves purification from harmful impurities by 80%, due to which protium water is considered the most optimal for human life.

Meaning in nature

The fact that ice floats on the surface of bodies of water plays an important role in nature. If the water did not have this property and the ice sank to the bottom, this would lead to freezing of the entire reservoir and, as a result, the death of the living organisms inhabiting it.

When cold weather occurs, first at temperatures above +4 ºС, colder water from the surface of the reservoir sinks down, and warm (lighter) water rises. This process is called vertical circulation (mixing) of water. When it reaches +4 ºС throughout the entire reservoir, this process stops, since from the surface the water already at +3 ºС becomes lighter than that which is below. Water expands (its volume increases by approximately 10%) and its density decreases. As a consequence of the fact that the colder layer is on top, water freezes on the surface and an ice cover appears. Due to its crystalline structure, ice has poor thermal conductivity, meaning it retains heat. The ice layer acts as a kind of heat insulator. And the water under the ice retains its heat. Thanks to the thermal insulating properties of ice, the transfer of “cold” to the lower layers of water is sharply reduced. Therefore, at least a thin layer of water almost always remains at the bottom of a reservoir, which is extremely important for the life of its inhabitants.

Thus, +4 ºС - the temperature of maximum density of water - is the temperature of survival of living organisms in a reservoir.

Use in everyday life

Mentioned above was the possibility of water pipes bursting when water freezes. To avoid damage to the water supply system at low temperatures, there should be no interruptions in the supply of warm water that flows through the heating pipes. A vehicle is exposed to a similar danger if water is left in the radiator in cold weather.

Now let's talk about the pleasant side of the unique properties of water. Ice skating is great fun for children and adults. Have you ever wondered why ice is so slippery? For example, glass is also slippery, and also smoother and more attractive than ice. But skates don't glide on it. Only ice has such a specific delightful property.

The fact is that under the weight of our weight there is pressure on the thin blade of the skate, which, in turn, causes pressure on the ice and its melting. In this case, a thin film of water is formed, against which the steel blade of the skate slides.

Difference in freezing of wax and water

Experiments show that the surface of an ice cube forms a certain bulge. This is due to the fact that freezing in the middle occurs last. And expanding during the transition to a solid state, this bulge rises even more. This can be counteracted by the hardening of wax, which, on the contrary, forms a depression. This is explained by the fact that the wax contracts after turning into a solid state. Liquids that contract uniformly when frozen form a somewhat concave surface.

To freeze water, it is not enough to cool it to the freezing point of 0 ºC; this temperature must be maintained through constant cooling.

Water mixed with salt

Adding table salt to water lowers its freezing point. It is for this reason that roads are sprinkled with salt in winter. Salty water freezes at temperatures of -8 °C and below, so until the temperature drops to at least this point, freezing does not occur.

An ice-salt mixture is sometimes used as a “cooling mixture” for low-temperature experiments. When ice melts, it absorbs the latent heat required for the transformation from its surroundings, thereby cooling it. This absorbs so much heat that the temperature can drop below -15 °C.

Universal solvent

Pure water (molecular formula H 2 0) has no color, no taste, no smell. The water molecule consists of hydrogen and oxygen. When other substances (soluble and insoluble in water) get into the water, it becomes polluted, which is why there is no absolutely pure water in nature. All substances that occur in nature can be dissolved in water to varying degrees. It's determined by them unique properties- solubility in water. Therefore, water is considered a “universal solvent.”

Guarantor of stable air temperature

Water heats up slowly due to its high heat capacity, but, nevertheless, the cooling process occurs much more slowly. This makes it possible to summer time years to accumulate heat in the oceans and seas. The release of heat occurs in winter, due to which there is no sharp change in air temperature on the territory of our planet throughout the year. Oceans and seas are the original and natural heat accumulator on the Earth.

Surface tension

Conclusion

The fact that ice does not sink, but floats on the surface, is explained by its lower density compared to water (the specific density of water is 1000 kg/m³, of ice - about 917 kg/m³). This thesis is true not only for ice, but also for any other physical body. For example, the density of a paper boat or an autumn leaf is much lower than the density of water, which ensures their buoyancy.

However, the property of water to have a lower density in the solid state is very rare in nature, with the exception of general rule. Only metal and cast iron (an alloy of the metal iron and the nonmetal carbon) have similar properties.

- the smallest ocean on Earth by area, located between Eurasia and North America. Area 14.75 million square meters. km, average depth 1225 m, greatest depth 5527 m in the Greenland Sea. The volume of water is 18.07 million km³.

This ocean is distinguished by its harsh climate, abundance of ice and relatively shallow depths. Life there is entirely dependent on the exchange of water and heat with neighboring oceans.

The Arctic Ocean is the smallest of the Earth's oceans. It is the shallowest. The ocean is located in the center of the Arctic, which occupies all the space around North Pole, including the ocean, adjacent parts of continents, islands and archipelagos.

A significant part of the ocean area is made up of seas, most of which are marginal and only one is internal. There are many islands in the ocean located near the continents.

History of ocean exploration. The exploration of the Arctic Ocean is the story of the heroic exploits of many generations of sailors, travelers and scientists from a number of countries. In ancient times, Russian people - Pomors - set out on journeys on fragile wooden boats and boats. They spent the winter on Grumant (Spitsbergen) and sailed to the mouth of the Ob. They fished, hunted sea animals and knew well the conditions of navigation in polar waters.

Using information about Russian voyages, the British and Dutch attempted to find the shortest routes from Europe to the countries of the East (China and India). As a result of the voyage of Willem Barents at the end of the 16th century. a map of the western part of the ocean was compiled.

The systematic study of the ocean shores began with the Great Northern Expedition (1733-1743). Its participants accomplished a scientific feat - they walked and mapped the coast from the mouth of the Pechora to the Bering Strait.

The first information about the nature of the circumpolar regions of the ocean was collected in late XIX V. during the drift of Fram Nansen and the voyage to the Pole at the beginning of the twentieth century. G. Sedova on the schooner “St. Foka."

The possibility of crossing the ocean in one navigation was proven in 1932 by the expedition of the icebreaker Sibiryakov. The participants of this expedition, under the leadership of O. Yu. Schmidt, took depth measurements, measured the thickness of the ice, and observed the weather.

Our country has developed new methods for studying this ocean. In 1937, the first polar station “North Pole” (SP-1) was established on a drifting ice floe. Four polar explorers led by I.D. Papanin carried out a heroic drift on an ice floe from the North Pole to the Greenland Sea.

To study the ocean, they now use airplanes that land on ice floes and carry out one-time observations. Images from space provide information about changes in the state of the atmosphere over the ocean and the movement of ice.

As a result of all these studies, a large amount of material has been accumulated about the nature of the Arctic Ocean: about the climate, the organic world; the structure of the bottom topography was clarified, bottom currents were studied.

Many secrets of the nature of the Arctic Ocean are already known, but much remains to be discovered by future generations, including, perhaps, some of you.

The bottom topography has a complex structure. The central part of the ocean is crossed by mountain ranges and deep faults. Between the ridges there are deep-sea depressions and basins. A characteristic feature of the ocean is a large shelf, which makes up more than a third of the ocean floor area.

Climatic features are determined by the polar position of the ocean. Arctic air masses prevail over it. Fogs are frequent in summer. Arctic air masses are much warmer than air masses forming over Antarctica. The reason for this is the heat reserve in the waters of the Arctic Ocean, which is constantly replenished by the heat of the waters of the Atlantic and, to a lesser extent, the Pacific Ocean. Thus, oddly enough, the Arctic Ocean does not cool, but significantly warms the vast land areas of the Northern Hemisphere, especially in the winter months.

Under the influence of western and southwestern winds from the North Atlantic, a powerful flow of warm waters of the North Atlantic Current enters the Arctic Ocean. Along the coast of Eurasia, waters move from west to east. Across the entire ocean from the Bering Strait to Greenland, water moves in the opposite direction - from east to west.

The most characteristic feature the nature of this ocean is the presence of ice. Their formation is associated with the low temperature and relatively low salinity of surface water masses, which are desalinated by a large amount of river water flowing from the continents.

The removal of ice to other oceans is difficult. Therefore, multi-year ice with a thickness of 2-4 m or more prevails here. Winds and currents cause the movement and compression of ice, the formation of hummocks.

The bulk of organisms in the ocean are algae, which can live in cold water and even on ice. Organic world it is rich only in the Atlantic region and on the shelf near river mouths. Plankton is formed here, algae grows on the bottom, and fish live (cod, navaga, halibut). Whales, seals, and walruses live in the ocean. The Arctic is inhabited by polar bears and seabirds that lead a colonial lifestyle and live on the shores. The entire population of the giant “bird colonies” feeds in the ocean.

There are two natural zones in the Arctic Ocean. The boundary of the polar (Arctic) belt in the south approximately coincides with the edge of the continental shelf. This deepest and harshest part of the ocean is covered with drifting ice. In summer, the ice floes are covered with a layer of melt water. This belt is unsuitable for living organisms.

The part of the ocean adjacent to land belongs to the subpolar (subarctic) belt. These are mainly the seas of the Arctic Ocean. Nature here is not so harsh. In summer, the water off the coast is free of ice and is highly desalinated by rivers. Warm waters from the Atlantic penetrating here create conditions for the development of plankton, which fish feed on.

Kinds economic activity in the ocean. The Arctic Ocean is of exceptional importance for the countries whose shores are washed by its waters. The harsh nature of the ocean makes it difficult to search for minerals. But oil and natural gas deposits have already been explored on the shelf of the Kara and Barents Seas, off the coast of Alaska and Canada.

The biological wealth of the ocean is small. In the Atlantic region they fish and obtain seaweed, and hunt seals. Whale production in the ocean is strictly limited.

There are many ways to explore the Arctic. Automatic scientific complexes - meteorological and oceanographic stations, mass balance buoys, which are frozen into the ice and make it possible to determine the increase or change in the mass of the ice cover (by the way, such a buoy works on SP-37) - greatly facilitate data collection, but have their limitations. Of course, it would be tempting to sit in the office while data arrives via satellite communications from a system, for example, automatic hydrological stations - mooring or drifting buoys. But in a year, more than 50% of such (very expensive) buoys are usually lost - in this region, working conditions are quite difficult even for equipment specially designed for this due to the dynamics of ice fields (hummocking, compression).

Another way to obtain scientific data is through remote sensing of the Earth. Scientific satellites (unfortunately, not Russian ones) make it possible to obtain information about ice conditions in the visible, infrared, radar and microwave ranges. This data is mainly used for applied purposes: for guiding ships, for searching for suitable ice floes for drifting stations; at the drifting stations themselves, they help in the work - for example, at SP-36 they were used to locate a site suitable for constructing a runway. However, satellite information must be verified by comparing it with real observations - directly measured ice thickness, its age (it is not yet possible to directly measure this data from a satellite).

Scientific stations (already inhabited) can also be placed by freezing ships in ice (this method was tested by Fridtjof Nansen). From time to time such projects are carried out; examples include the French yacht Tara or the American-Canadian SHEBA project involving a ship drifting in the Beaufort Sea. A similar project was considered for the nuclear icebreaker Arktika, but in the end it was abandoned for various reasons. However, frozen ships provide only a good base for the life of scientific personnel and energy supply for the scientific complex. To collect scientific data, people will still have to go to the ice to exclude outside influences. In addition, freezing ships is expensive (and distracts ships from their main work).


“In my opinion, drifting ice is a natural load-bearing platform, the most optimal for both hosting a scientific complex and for people to live in,” says Vladimir Churun. “It allows you to drift for a long time and obtain pure scientific data without any outside influence. Of course, people on the ice floe are deprived of some comfort, but in the name of science we have to put up with this. Of course, obtaining scientific data must be carried out in a comprehensive manner, using all available means - drifting stations, air expeditions, satellite observation, automatic buoys, and scientific expedition vessels.”

“The scientific program of SP-36 was quite extensive and successful,” Vladimir Churun ​​explains to Popular Mechanics. “It included meteorological, aerological and hydrological observations, as well as studies of the properties of ice and snow cover. But research related to the ionosphere and magnetic field The lands, which received considerable attention at drifting stations in Soviet times, have now been transferred to stationary polar stations on the mainland and on the islands.”

Air

The beginning of the station's work is not marked by the solemn moment of raising the Russian flag over the wardroom. Officially, the drifting station begins its work from the moment the first weather report is transmitted to the AARI, and from there to the global meteorological network. Since, as we know, “the Arctic is the kitchen of weather,” these data provide meteorologists with extremely valuable information. The study of baric (pressure, wind speed and direction at various altitudes) and temperature profiles of the atmosphere using probes up to an altitude of 30 km is used not only for weather prediction - this data can later be used for fundamental scientific purposes, such as refining models of atmospheric physics, and for applied ones - for example, supporting aircraft flights. Meteorologists and aerologists are responsible for all this data.

The work of a meteorologist may seem simple - it is taking meteorological data and sending it to Roshydromet. To do this, a set of sensors is located on a 10-meter weather mast that measures wind speed and direction, temperature and humidity, visibility and pressure. All information, including from remote sensors (snow and ice temperature, solar radiation intensity), flows to the weather station. Although data is taken from the station remotely, it is not always possible to carry out measurements without going to the weather site. “The cups of the anemometers and the radiation protection of the weather booth, where the temperature and humidity sensors are located, freeze over, they have to be cleared of frost (to access the top of the mast, the latter is made ‘breakable’), explains SP-36 meteorologist engineer Ilya Bobkov.- A During the melting period, the guy ropes have to be constantly reinforced to keep the mast stable. In addition, the station is not designed to operate in such severe frost conditions, below - 40°C, so we installed a heating device there - a regular 40-watt incandescent lamp. Of course, there are stations designed for such low temperatures, but they are less accurate.”

Above 10 m is the area of ​​work for aerologists. “We study the upper layers of the atmosphere using aerological probes,” explains SP-36 leading aerological engineer Sergei Ovchinnikov. - The probe is a box weighing 140 g, it is attached to a balloon - a ball with a volume of about 1.5 m 3 filled with hydrogen, which is obtained chemically in a high-pressure gas generator - from ferrosilicon powder, caustic soda and water. The probe has a built-in GPS receiver, a telemetry transmitter, as well as temperature, pressure and humidity sensors. Every two seconds, the probe transmits information along with its coordinates to a ground receiving station.” The coordinates of the probe make it possible to calculate its movement, wind speed and direction at various altitudes (altitude is determined by barometric method). The probe's electronics are powered by a water-filled battery, which is first kept in water for several minutes (life jackets with emergency beacons are equipped with similar power sources).

“The probes are launched every day at 0 and 12 o’clock GMT, if weather conditions permit; in strong winds, the probe simply “nails” to the ground. In less than a year, 640 releases took place, says Sergei Ovchinnikov. “The average ascent height was 28,770 m, the maximum was 32,400 m. The probe’s ascent speed was about 300 m per minute, so it reached its maximum height in about an hour and a half, the balloon as the lift swells, and then bursts, and the probe falls to the ground. True, it is almost impossible to find it, so the device is disposable, albeit expensive.”

Water

“The main emphasis in our work is on measuring current parameters, as well as temperature, electrical conductivity, and water density,” says SP-36 oceanologist Sergei Kuzmin. last years The fleet of instruments has been significantly updated, and now we can obtain results with high accuracy that correspond to the world level. We now use profiling instruments that allow us to measure flow velocity using the transverse Doppler effect in several layers.

"We mainly studied Atlantic currents, the upper boundary of which is at a depth of 180-220 m, and the core - 270-400 m." In addition to studying currents, a daily study of the water column was provided using a probe that measured electrical conductivity and temperature; every six days, studies were carried out at a depth of up to 1000 m to “capture” the Atlantic waters, and once a week the probe was lowered to the entire maximum length of the cable - 3400 m to study the deep sea layers. “In some areas,” explains Sergei Kuzmin, “a geothermal effect can be observed in deep layers.”

The task of oceanologists on SP-36 also included collecting samples for subsequent analysis by hydrochemists. “Three times during the winter - in spring, summer and autumn - we took an ice core, which was then melted at room temperature, the resulting water was passed through a filter, and then frozen again,” says Sergei. - Both the filter and the ice were specially packaged for subsequent analysis. Snow samples and subglacial water were collected in the same way. Air samples were also taken using an aspirator, which pumped air through several filters that retained the smallest particles. Previously, in this way it was possible, for example, to detect pollen of some plant species that flies to the polar regions from Canada and the Russian taiga.”

Why study currents? “By comparison with data accumulated over previous years, climate trends can be determined,” Sergei replies. - Such an analysis will make it possible to understand, for example, the behavior of ice in the Arctic Ocean, which is extremely important not only from a fundamental point of view, but also from a purely applied point of view - for example, when developing natural resources Arctic".

Snow

The program of special meteorological research included several sections. The structure of the snow and ice cover, its thermophysical and radiation properties were studied - that is, how it reflects and absorbs solar radiation. “The fact is that snow has a high reflectivity, and according to this characteristic, for example in satellite images, it very much resembles a cloud layer,” explains meteorologist Sergei Shutilin. - Especially in winter, when the temperature in both places is several tens of degrees below zero. I studied the thermophysical properties of snow depending on temperature, wind, cloudiness and solar radiation.” The penetration of solar radiation (of course, during the polar day) through snow and ice to various depths (including into water) was also measured. The morphology of snow and its thermophysical properties were also studied—temperature at various depths, density, porosity, and fractional composition of crystals in various layers. These data, together with radiation characteristics, will help clarify the description of snow and ice cover in models of various levels - both global and regional climate models.

During the polar day, measurements of ultraviolet radiation reaching the Earth's surface were carried out, and during the polar night, gas analyzers were used to study the concentrations of carbon dioxide, ground-level ozone and methane, emissions of which in the Arctic are apparently associated with geological processes. Using a special gas analyzer, it was also possible to obtain, according to Sergei Shutilin, unique data on the flow of carbon dioxide and water vapor through the surface of snow and ice: “Previously, there was a model according to which melt water from the coast fell into the ocean, the ocean became covered with ice, and under it anaerobic processes took place. And after the surface was freed from ice, a flow of carbon dioxide entered the atmosphere. We discovered that the flow goes in the opposite direction: when there is no ice, it goes into the ocean, and when there is ice, it goes into the atmosphere! However, this may also depend on the area - for example, measurements on SP-35, which drifted closer to the south and to the shelf seas in the eastern hemisphere, are consistent with the above hypothesis. So more research is needed."

Ice is now receiving the closest attention, because it is a clear indicator of the processes taking place in the Arctic. Therefore, its study is extremely important. First of all, this is an assessment of the ice mass balance. It melts in the summer and grows in the winter, so regular measurements of its thickness using measuring rods at a designated site make it possible to estimate the rate of melting or growth of the ice floe, and these data can then be used to refine various models of multi-year ice formation. “At SP-36, the landfill occupied an area of ​​80x100 m, and from October to May 8,400 tons of ice grew on it,” says Vladimir Churun. “You can imagine how much ice has grown on the entire ice floe measuring 5x6 km!”

“We also took several cores of young and old ice, which will be examined at the AARI,” chemical composition, mechanical properties, morphology,” says SP-36 ice researcher Nikita Kuznetsov. “This information can be used to refine various climate models, and also, for example, for engineering purposes, including for the construction of icebreakers.”

In addition, at SP-36, studies were carried out on the processes of passage of various waves in sea ​​ice: waves formed during collisions of ice floes, as well as passing from the marine environment into ice. These data are recorded using highly sensitive seismometers and are subsequently used for applied models of ice interaction with solids. According to the leading engineer-ice researcher of SP-36, Leonid Panov, this makes it possible to evaluate the loads on various engineering structures - ships, drilling platforms, etc. - from the point of view of ice resistance: “Knowing the features of the interaction of ice with waves, it is possible to calculate the strength properties of ice , which means predicting exactly where it will break. Such methods will make it possible to remotely detect the passage of cracks and hummocking in dangerous areas, for example, near oil and gas pipelines.”

Not a resort

When I asked Vladimir how global climate change (namely - global warming) while working at a drifting station, he only smiled in response: “Of course, the area of ​​ice and its thickness in the Arctic have decreased - this is a completely registered scientific fact. But at a drifting station, in the local space of the ice floe, global warming is not felt at all. In particular, during this wintering we recorded the minimum temperature in the last ten years (-47.3°C). The wind was not very strong - the maximum gusts were 19.4 m/s. But overall the winter from February to April was very cold. So, despite global warming, the Arctic has not become warmer, cozier, or more comfortable. It’s still just as cold here, the cold winds are still blowing, the ice is still the same all around. And there is no hope yet that Chukotka will soon become a resort.”

Dmitry Mamontov.