Procedure for the population to act in case of avalanches. Avalanche - what is it? Causes and consequences of avalanches

Snow avalanches are associated with mountainous terrain and pose serious risks to people, road infrastructure, bridges and buildings.


Climbers and lovers of mountain recreation often encounter this natural phenomenon, and, despite all precautions, an avalanche is an element from which there is practically no escape and no hope of survival. Where does it come from and what danger does it pose?

What is an avalanche?

According to explanatory dictionaries, term "avalanche" comes from the Latin word labina, which means "landslide" . The phenomenon is a huge mass of snow that falls or slides down mountain slopes and rushes into nearby valleys and depressions.

To one degree or another, avalanches are common in all high-mountain regions of the world. In warmer latitudes they usually occur in winter time, and in those places where the mountains are covered with caps of snow all year round, they can melt in any season.


Snow in avalanches reaches a volume of millions of cubic meters and during the descent sweeps away everything in its path.

Why do avalanches occur?

Precipitation that falls in the mountains is retained on the slopes due to friction. The magnitude of this force is influenced by many factors, such as the steepness of the mountain peak and the moisture content of the snow mass. As snow accumulates, its weight begins to exceed the force of friction, causing large snow caps to slide down the mountain and collapse along its flanks.

Most often, avalanches occur on peaks with a slope angle of about 25–45 degrees. On steeper mountains, snow melting occurs only under certain conditions, for example, when it falls on an ice sheet. On flatter flanks, avalanches usually do not occur due to the impossibility of accumulating large snow masses.

The main reason for avalanches lies in the current climatic conditions region. Most often they occur during thaws or rains.

Sometimes earthquakes and rockfalls can trigger snow melting, and in some cases, a loud sound or small pressure such as weight is enough to cause a disaster. human body.

What types of avalanches are there?

There is a fairly extensive classification of avalanches, differing in volume, path, snow consistency and other characteristics. In particular, depending on the nature of the movement, there are wasp avalanches that descend over the entire surface of the mountain, flume avalanches that slide along hollows, and jumping avalanches that fly part of the way after encountering any obstacles.


According to their consistency, natural phenomena are divided into dry, which occur at low air temperatures due to low friction force, and wet, which are formed during thaws as a result of the formation of a layer of water under the snow.

How is avalanche risk calculated?

In order to identify the likelihood of avalanches, a risk classification system was created in Europe in 1993, in which each level is indicated by a flag of a certain format. Such flags are hung at all ski resorts and allow vacationers to assess the possibility of tragedy.

The system includes five risk levels depending on the stability of the snow. According to statistics, in the mountainous regions of Switzerland, most deaths are recorded already at levels 2 and 3, while in the French mountains the disaster leads to deaths at levels 3 and 4.

How dangerous is an avalanche?

Avalanches pose a danger to people due to their large mass. If a person finds himself under a thick layer of snow, he dies from suffocation or shock resulting from broken bones. Snow has low sound conductivity, so rescuers are not able to hear the victim’s scream and find him under the snow mass.


Avalanches can pose a threat not only to people stranded in the mountains, but also to nearby populated areas. Sometimes snow melting leads to catastrophic consequences and completely destroys the infrastructure of villages. So, in 1999, an avalanche destroyed the Austrian town of Galtür and caused the death of 30 of its residents.

Trouble usually appears suddenly, causing chaos and panic. Only advance preparation and unity of the peoples of the world in the face of threatening natural dangers gives humanity a great chance of survival and joint overcoming of difficulties in an era associated with global climate change on the planet. from the Report « »

This memo will tell you what to do if you find yourself in an area with a likelihood of an avalanche and the associated consequences.

An avalanche is a mass of snow falling at an increasing speed (from 20 to 1000 m/s). In its sliding along steep mountain slopes, an avalanche sweeps away everything in its path, covering significant distances, capturing new portions of snow, ice, and small rock, increasing its volume. The impact force of the elements often amounts to tens of tons per square meter. When the avalanche begins its downward movement, an air wave is formed, which clears the path for the avalanche. Its destructive power is capable of demolishing buildings and filling up roads. Before a snow mass collapses, a dull sound is heard high in the mountains, followed by a snow cloud rushing at great speed into the valley, where it stops. Most often, avalanches form in open areas of the mountain, where there are no trees that could slow down the movement of the snow mass.

How dangerous are avalanches?

The impact force of an avalanche can destroy even strong concrete buildings, twist metal power transmission masts, and throw not only cars off the road. but also trains, turning equipment into piles of scrap metal. A layer of many meters of dense snow forms on the roads.

A system has now been developed to warn people about the danger of avalanches. It includes a system for classifying the risk of avalanches, the levels of which are indicated by flags and posted at ski resorts and resorts.

1. Refrain from hiking;
2. Avoid dangerous slopes. You cannot cross them crosswise or move in a zigzag, as this can “cut” the snow cover, disrupt the adhesion of the snow to the underlying surface and cause an avalanche. It is best to move along the slope straight up, at as a last resort- obliquely.
3. Do not go to the mountains after heavy snowfalls for 2-3 days;
4. It is recommended to stay in a group of more than 3 people;
5. When going out into the mountains, it is advisable to take with you an avalanche transceiver, a mobile phone so that rescuers have the opportunity to find a person covered in snow, as well as special avalanche backpacks;
6. It is not recommended to step on snow ledges.

What to do if you find yourself near an avalanche?

1. Move horizontally out of the path of the avalanche to a safe place.
2. Hide behind a ledge or in a cave.
3. Climb onto an elevated surface, a stable rock, or strong tree(you can’t hide behind young trees, as snow can break them)
4. Quickly free yourself from all things that can be pulled into the rushing stream and hinder your movements: a backpack, skis, poles, an ice ax.

What to do if you find yourself under thick snow

1. Cover your nose and mouth with a scarf or hat to prevent snow from getting there;
2. Group up: take a horizontal position, turning in the direction of the snow flow, pull your knees to your stomach;
3. By rotating your head in a circular motion, create as much free space in front of your face as possible;
4. When the avalanche stops, try to get out on your own or try to push your hand up so that rescuers notice it;
5. If you find yourself in an avalanche, do not scream - the snow completely absorbs sounds, and screams and meaningless movements only deprive you of strength, oxygen and warmth;
6. To stay warm, don't forget to move.
7. Don’t lose your composure, help those around you whenever possible, don’t let yourself and the people around you fall asleep, remember that they are looking for you. There are cases when people were rescued from an avalanche on the fifth and even thirteenth day.

It is important in any emergency situation to remember one immutable truth: no matter what happens, maintaining self-control, through joint, consolidated and friendly actions it is possible to overcome any difficulty and greatly increase the chances of survival. By helping other people, we thereby help ourselves. After all, as stated in the Report « » :

We are all people and we all have one place of residence - the Earth, one nationality - humanity, one value - life, thanks to which we can worthily realize ourselves and the meaning of our existence in the highest spiritual and moral aspect.

UNITING PEOPLE IS THE KEY TO THE SURVIVAL OF HUMANITY!

Mont Tremblant, Vail, Zermatt, Kitzbühel, Are you familiar with these names? I think that most people don’t understand what we’re talking about, but some saw their favorite vacation spots in these names, because these are some of the most popular ski resorts in the world. Today, many people prefer to spend time doing extreme sports, as they say, being “on the wave.”

Ski resorts are fresh air and magnificent mountain scenery, but do not forget to be vigilant, where there is snow and large snow-capped mountains, there is a possibility of snow collapse.

In our article we want to tell you as much as possible about avalanches and what to do if you are suddenly threatened by an avalanche.

So, let's look at what an avalanche is?

If we talk in simple language, then an avalanche is an uncontrolled flow of snow with a large mass, sliding down the mountain slopes with great speed.

The mass of avalanches can reach several hundred thousand tons, moving snow flow at a speed of 20 to 50 meters per second. Now imagine for a moment what such an avalanche could do to the nearest city, not to mention a person. From historical information: the largest avalanche was recorded in Austria in 1999, the mass of snow that came down from the mountains was 170 thousand tons, and an entire village was destroyed when it collapsed.

What to do if there is a threat of an avalanche

Look around and try to immediately get out of the way of the avalanche, try to find shelter! It could be huge tree, a large stone, or rocky outcrop.

DO NOT ATTEMPT to outrun an avalanche! Remember, its speed can reach up to 450 km/h, when the absolute world speed record for a skier is 251 km/h.

When an avalanche approaches, get ready to tightly cover your nose and mouth with a scarf or collar; if you get into the avalanche flow, try to stay close to the top of the afloat, moving in the direction of the avalanche as close to the edge as possible - this may well increase the chances of survival.

After the avalanche stops, there are two outcomes, as you probably already understood, the first outcome is that you are at the top of the avalanche, that is, on the surface, and the second, more unpleasant case, is when you are in the thickness of the snow inside the stopped avalanche.

Let's consider both cases in order

In the first case: You managed to control the avalanche and find yourself on the surface, now look around and check externally, if there are no visible damages, try to get to the nearest populated area and apply for help. medical care, since you may not feel internal damage to your organs while in a state of shock from what happened. We would also like to draw your attention DO NOT try to call for help unless absolutely necessary, your scream may cause another avalanche.

In the second case: You find yourself inside a “snow monster”. Try to remember how long you were captivated by snow and how approximately you could have been covered with snow, this will give you the opportunity to distribute your forces. Create space in the chest and face area so that you can breathe without pressure. Pull yourself together, concentrate, DON'T PANIC, remember, help may be on the way! But until the rescuers arrive, your life is now in your hands! Having completed the above steps, begin to get out of the snow captivity, rake the space in front of you with your hands, and move up.

How to rescue from an avalanche

What to do if you panic at the sight of an avalanche

You are not confident in your abilities; you will not be able to swim with the flow of the avalanche and resist its powerful effects. Well, in this case, there is a recommendation for you too.

When you see a snow stream, get rid of foreign objects, such as a backpack, skis, etc. Take a horizontal position, lie on the ground in the direction of the avalanche movement, tuck your knees to your chest and tuck yourself together. If you are very lucky, then the flow of snow can throw you up like a “snowball” to the edge of the avalanche, otherwise you will find yourself under a thick layer of snow, but nevertheless you are alive and there is a chance of salvation, use our rescue tips. Briefly about what to do in case of an avalanche

Called a tiger in the skin of a lamb by an innocent, at first glance, White snow Matthias Zdarsky is an Austrian researcher who studied the question of what an avalanche is. Softly falling snow fascinates even those who don’t like winter - the picture is too beautiful, similar to fairy tale. And the crystal stars smoothly falling to the ground create a deceptive impression of fragility and defenseless tenderness. However, excessively active snowfalls are fraught with danger, and a serious one. After all, not only snowdrifts, but also avalanches can grow from small snowflakes. So what is an avalanche? The definition of this concept is given below. And now a little history.

A brief excursion into history

In all likelihood, an avalanche is a phenomenon that exists as long as the steep slopes of mountains, and Polybius mentions the first large-scale snowfalls, causing the death of hundreds of people, in the context of the history of the campaign of the Carthaginian army through the Alps. And in general, this mountain range, beloved by tourists and climbers, has a long history of disasters behind it. It is not for nothing that in the 20th century, in some areas, masses were celebrated in memory of those killed under snow rubble, because in this case an avalanche means pain and grief for the relatives and friends of those who suffered from it. It is also noteworthy that in one of the last winters of the First World War, more soldiers died from this on the Austro-Italian front than directly during hostilities. And December 16, 1916 went down in history as “Black Thursday,” when six thousand people were missing in one day. Hemingway, who was in the Alps during the same time period and described his definition of what an avalanche means, noted that winter landslides are terrible, sudden and bring with them instant death.

Residents of Norway, Iceland, Bulgaria, the United States also suffered from the “white death”. Russian Federation, Canada, as well as Asian countries: Turkey, Nepal, Iran, Afghanistan, and in the latter, by and large, no records of the dead are kept. Tens of thousands of lives were also attributed to snow avalanches that fell from Mount Huascaran in Peru.

What is an avalanche? Etymology of the word

The ancient Romans called this phenomenon a “pile of snow.” Each nation had its own definition. What does avalanche mean? It's beautiful, exciting and dangerous a natural phenomenon. The very meaning of the word “avalanche” is also interesting, the origins of which are the Latin root lab, meaning “instability”, although it came into the Russian language through German, since in ancient German there was a definition of Lavine. Xuan Zang poetically called them “white dragons,” and in Pushkin’s time avalanches were called landslides. In the Alps and the Caucasus, the names of individual mountains, gorges and valleys are already “speaking”. For example, Lansky Forest or Zeygalan Khokh (“the mountain from which avalanches always come down”). Sometimes the ability to read onomastics, although it won’t tell you everything about snow debris, can protect you from unforeseen circumstances.

What is an avalanche

An avalanche is a type of landslide, a significant mass of snow that moves or even falls from the slopes of mountains under the influence of gravity. It simultaneously creates an air wave, which accounts for a significant part of the destruction and damage that is almost inevitable in this natural disaster.

Having started its movement, the avalanche can no longer stop, falling lower and lower and capturing accompanying stones, ice blocks, branches and uprooted trees on its way, turning from seething white snow into a dirty mass, vaguely reminiscent of a mudflow. The flow can continue its “fascinating journey” until it stops in flat areas or at the bottom of the valley.

Factors influencing the descent of snow masses from the mountains

The reasons that cause avalanches largely depend on the old snow - its height and density, the condition of the surface underneath it, as well as on the increase in new masses of precipitation. The intensity of snowfall, subsidence and compaction of the cover, and air temperature also influence. In addition, a fairly long open slope (100-500 m) is optimal for the start of an avalanche path.

It is not for nothing that the main “architect” of this natural phenomenon is called the wind, since an increase of 10-15 cm is enough for the snow to melt. Temperature is also one of the most important factors that can provoke a disaster. Moreover, if at zero degrees the instability of the snow, although it arises quickly, passes no less actively (it either melts or an avalanche occurs). And when the low temperature is stable, the avalanche period increases.

Seismic vibrations can also activate snow melting, which is not uncommon in mountainous areas. In some cases, jet flights over dangerous zones are enough.

In general, the increasing frequency of snow avalanches is indirectly or directly related to stormy economic activity a person who is not always reasonable. For example, forests that are now cut down used to serve as natural protection against snow slides.

Periodicity

Depending on the frequency of occurrence, intra-annual convergence is distinguished (for winter and spring periods) and the long-term average, which includes, respectively, the overall frequency of avalanche formation. There are also systematic avalanches (annually or every 2-3 years) and sporadic ones, which occur at most twice per century, which makes them especially unpredictable.

Movement, source of natural phenomenon

The nature of the movement of snow masses and the structure of the source determine the following classification: flume snow avalanches, special and jumping. In the case of the former, the snow moves either along a tray or along a specific channel. Special avalanches cover the entire accessible area of ​​​​the terrain while moving. But with the jumping ones it’s already more interesting - they are degenerated from the flume, appearing in places where the drainage is uneven. The snow mass has to “bounce”, as it were, to overcome certain areas. The latter type is capable of developing the highest speed, therefore the danger is very significant.

Snow is treacherous and may well creep up unnoticed and silently, falling with an unexpected shock wave, destroying everything in its path. The peculiarities of the movement of these natural masses underlie another division into types. It distinguishes a layer avalanche - this is when the movement occurs tangent to the surface of the snow located below, as well as a ground avalanche - it slides directly along the ground.

Scale

Depending on the damage caused, avalanches are usually divided into especially dangerous (they are also spontaneous) - the volume of material losses amazes the imagination with their scale, and simply dangerous - they complicate the activities of various organizations and jeopardize the peaceful, measured life of populated areas.

Properties of snow

It is also important to note the classification associated with the properties of the snow itself, which is the basis of the avalanche. There are dry, wet and wet. The former are characterized by a high speed of convergence and a powerful destructive air wave, and the masses themselves are formed at fairly low temperatures after significant snowfalls. A wet avalanche is snow that has decided to leave its cozy slopes at temperatures above zero. The speed of movement here is lower than in the previous ones, however, the density of the cover is greater. In addition, the base can freeze, turning into a hard and dangerous layer. For wet avalanches, the raw material is viscous, wet snow, and the mass of each cubic meter is about 400-600 kg, and the movement speed is 10-20 m/sec.

Volumes

Well, the simplest division is small and almost harmless, medium and dangerous to humans, as well as large ones, which in their path wipe out buildings and trees from the face of the earth, and turn vehicles into a pile of scrap metal.

Is it possible to predict the occurrence of avalanches?

It is extremely difficult to predict avalanches with a high degree of probability, since snow is an element of nature, which, by and large, is practically unpredictable. Of course, there are maps of dangerous areas and both passive and active methods are being taken to prevent this phenomenon. However, the causes and consequences of avalanches can be different and very noticeable. Passive methods include special shield barriers, forest areas, and observation points for dangerous areas. Active actions consist of shelling areas of possible landslides from artillery and mortar installations in order to provoke the convergence of snow masses in small batches.

Snow avalanches sliding down the mountains in any of the options represent no matter how small or large they are. It is extremely important to take into account all the factors influencing the occurrence of snow masses and their movement along an uncertain route to unknown goals, so as not to sacrifice too expensive gifts to the elements.

All about avalanches: interesting facts

1. The avalanche speed can reach 100-300 km/h. A powerful air wave instantly turns houses into ruins, crushes rocks, demolishes cable cars, uproots trees and destroys all life around.
2. Avalanches can come from any mountain. The main thing is that they are covered with snow. If there have been no avalanches in a certain area for 100 years, then there is always the possibility that they may occur at any time.
3. Approximately 40 thousand to 80 thousand people lost their lives during the First World War, they were buried under avalanches in the Alps. Data is approximate.
4. In America (California), people surrounded Mount St. Gabriel with deep ditches. Their dimensions are equal to football fields. Avalanches descending from the mountain linger in these ditches and do not roll into populated areas.
5. This destructive natural phenomenon is called differently among different peoples. The Austrians use the word "schneelaanen", which means "snow flow", the Italians say "valanga", the French - "avalanche". We call this phenomenon an avalanche.

An avalanche is characterized by the significant destructive power of snow, which approaches, occurs suddenly, moves at a speed of over 10 m/s, and can reach over 15 meters in height. An avalanche is characterized by the rapid, sudden movement of snow and/or ice down steep mountain slopes. The main danger of a snow avalanche manifests itself in the form of a direct impact on people and obstacles (structures, buildings, life support systems). Avalanche hazard factors: significant number of injuries and casualties; collapse with a thin mass and destruction of houses and buildings, potentially dangerous objects, roads, bridges, engineering structures, life support systems; destruction of forests and significant losses to agriculture.

Actions of the population in case of threat, avalanches.

• 1. Listen carefully to the information on TV and radio about the situation, recommendations on the course of action.
• 2. Stay calm, warn your neighbors, provide assistance to the disabled, children and the elderly.
• 3. Remember that you can only escape from an avalanche by avoiding it. If there is time, precautionary evacuation of the population is organized in advance.
• 4. Prepare documents, clothes and collect the most necessary and valuable things, a small supply of food for several days, drinking water, medicines, a flashlight, a battery-powered receiver.
• 5. Turn off the electricity, gas and water supplies, extinguish the fire in the pipes.
• 6. Close windows, doors, ventilation and other openings tightly.
• 7. Remove flammable and toxic substances from the house and, if possible, hide them in pits or cellars.
• 8. Go out on your own to safe places on a hill in case of emergency evacuation (the evacuation route must be known in advance).
• 9. Dear travelers, remember these rules: do not go to the mountains in snowfall or bad weather; study your route before traveling to the mountains; keep an eye on weather changes in the mountains;
• 10. Remember that the most dangerous period for avalanches is spring and summer, from 10 a.m. to sunset;
• 11. Avoid places where avalanches are possible (often it happens when the slope is steeper than 300, if the slope is without bushes and trees - at a steepness of 200; and with a steepness of 450, avalanches happen almost after every snowfall);

Actions of the population in case of snow avalanches.

• 1. Stay calm, avoid panic, and if necessary, provide assistance to disabled people, children, elderly people and neighbors.
• 2. When you hear the sound of an approaching snow avalanche, immediately hide behind a rock or tree, lie on the ground, protect your head with your hands, press your knees to your stomach, orienting your body according to the movement of the avalanche and breathe through your clothes.
• 3. You are captured and carried away by an avalanche:
  • a) perform swimming movements and, if possible, stay from the edge of the avalanche, where the speed of movement is lower;
  • b) try to create space around the face and chest in case of an avalanche stopping, this will help your breathing;
  • c) do not scream if you find yourself inside an avalanche, the snow completely absorbs sounds, and screaming and meaningless movements will only deprive you of strength, oxygen and heat;
  • d) don’t panic and don’t let yourself fall asleep;
  • e) remember that they are looking for you and can save you for some time.

Actions of the population after an avalanche.

• 1. If possible, notify the local authorities of the nearest populated area about the disaster if you find yourself outside the avalanche zone.
• 2. Remain calm, reassure children and those who received mental trauma as a result of the mudflow (avalanche), assess the situation.
• 3. After getting out from under the avalanche snow on your own or with the help of rescuers, examine your body and consult a doctor, even if you consider yourself healthy.
• 4. If possible, help the victims, call for medical help for those who need it.
• 5. Assist, if necessary, rescuers in searching and rescuing victims.
• 6. Inform your relatives about your condition and whereabouts. Do not occupy the phone for a long time, but only to report a serious danger.
• 7. Make sure your home is not damaged. Visually inspect the condition of the electricity, gas and water supply networks. Do not use open fire, lighting, heaters, gas stoves, and do not turn them on until you are sure that there is no source of gas.
• 8. Stay away from houses, power poles, and high fences.
• 9. Don’t rush to inspect a populated area, don’t visit zones of destruction unless your help is needed there.
• 10. Find out from local government and local authorities the addresses of organizations that are responsible for providing assistance to the affected population.