Introduction 3

1. Origin and assessment of storms, hurricanes, tornadoes 5

2. Measures to ensure safety in the event of a threat of storms, hurricanes, tornadoes. 10

3. Actions of the population in case of a threat and during storms, hurricanes and tornadoes. 12

Conclusion 14

Bibliography 15

APPENDIX………………………………………………………………….16

Introduction

Emergencies 1 natural character threaten the inhabitants of our planet since the beginning of civilization.

In general, every 100,000th inhabitant of the earth perishes from natural disasters, and over the past hundred years - 16,000 annually. Natural disasters are terrible because of their unexpectedness: in a short period of time they devastate the territory, destroy homes, property, communications. One catastrophe, like an avalanche, is followed by others: famine, infections of disease.

Natural emergencies are divided into geological, meteorological, hydrological, natural fires, biological and space.

All natural emergencies are subject to some general patterns:

1. for each type of emergency, a certain spatial confinement is characteristic;
2. the greater the intensity (power) of a dangerous natural phenomenon, the less often it happens;
3. each natural disaster is preceded by some specific signs (precursors);
4. with all the unexpectedness of a particular natural emergency, its manifestation can be predicted;
5. in many cases, passive and active protective measures against natural hazards can be envisaged.

Speaking about natural emergencies, the role of anthropogenic influence on their manifestation should be emphasized. Numerous facts of imbalance in the natural environment as a result of human activity are known, leading to increased dangerous impacts.

At present, the scale of the use of natural resources has increased significantly, as a result, the features of the global environmental crisis have become tangible. Nature, as it were, takes revenge on man for a gross intrusion into her possessions. This circumstance should be borne in mind when carrying out business activities. Compliance with the natural balance is the most important preventive factor, taking into account which will reduce the number of natural emergencies.

There is a mutual connection between all natural disasters. The closest relationship is observed between earthquakes and tsunamis. Tropical cyclones almost always cause flooding. Earthquakes cause fires, gas explosions, dam breaks. Volcanic eruptions - poisoning of pastures, death of livestock, famine.

A prerequisite for successful protection against natural emergencies is the study of their causes and mechanisms. Knowing the essence of the processes, it is possible to predict them, and the timely and accurate forecast of hazardous phenomena is the most important condition for effective protection.

1. Origin and assessment of storms, hurricanes, tornadoes

Wind is the movement of air parallel to the earth's surface, resulting from the uneven distribution of heat and atmospheric pressure and directed from a high pressure zone to a low pressure zone. It is characterized by direction, speed and strength.

The direction of the wind is determined by the azimuth of the side of the horizon from which it blows, and is measured in degrees. Wind speed is measured in meters per second (m/s), kilometers per hour (km/h), knots (miles/h). The strength of the wind is measured by the pressure that it exerts on 1m 2 of the surface. The strength of the wind changes almost in proportion to its speed, so the strength of the wind is often estimated not by pressure, but by speed, which simplifies the perception and understanding of these quantities not only by specialists, but by all interested people.

Many words are used to indicate the movement of the wind: tornado, storm, hurricane, typhoon, cyclone and many local names. To systematize them, the Beaufort scale is used all over the world, which allows you to very accurately assess the strength of the wind in points (from 0 to 12) by its effect on ground objects or by waves at sea. This scale is also convenient in that it allows, according to the signs described in it, to fairly accurately determine the wind speed without instruments.

A breeze (from light to strong breeze) sailors call the wind, which has a speed of 4 to 31 miles per hour. In terms of kilometers (factor 1.6), this will be from 6.4 to 50 km / h.

A wind is called a storm, the speed of which reaches 20-32 m / s (70 - 115 km / h). In turn, depending on the strength of the wind, they differ:

1. storm - wind at a speed of 20 - 26 m / s;
2. strong storm - wind at a speed of 26 - 30.5 m / s;
3. severe storm - wind at a speed of 30.5 - 32 m / s.

A violent storm is sometimes called a storm.

Storms are divided into vortex and stream storms. Vortex storms are complex vortex formations caused by cyclonic activity and spreading over large areas. Stream storms are local phenomena of small distribution. They are peculiar, sharply isolated and inferior to eddy storms.

Vortex storms are dusty, snowy and squall. In winter they turn into snow. In Russia, such storms are often called snowstorms, snowstorms, or snowstorms.

Usually, dust storms take place in unstable weather, with the passage of atmospheric fronts. The desert, as it were, warns of an impending dust storm: first, animals flee, always in the opposite direction to the storm, then a black stripe appears near the horizon, which expands before our eyes and covers the entire sky in a few minutes. Inside the storm, visibility is negligible, temperatures drop, and it usually begins to rain a few minutes before the storm.

Squall storms arise, as a rule, suddenly, and are extremely short in time (several minutes). For example, within 10 minutes the wind speed can increase from 3 to 31 m/s.

Stream storms are divided into katabatic and jet. With stock, the air flow moves down the slope from top to bottom. Jets are characterized by the fact that the air flow moves horizontally or up the slope. They pass most often between the chains of mountains connecting the valleys.

A hurricane is a wind with a speed of more than 32 m/s (more than 115 km/h). Depending on the speed, they differ:

1. hurricanes - 32 - 39.2 m / s (115 - 140 km / h);
2. strong hurricanes- 39.2 - 46.2 m / s (140 - 170 km / h);
3. severe hurricanes - more than 48.6 m / s (more than 170 km / h).

Hurricanes are divided into tropical and extratropical. Tropical hurricanes are called hurricanes that originate in tropical latitudes, and extratropical - in extratropical ones. In addition, tropical hurricanes are often subdivided into hurricanes that originate over the Atlantic Ocean and over the Pacific. The latter are called typhoons.

Hurricanes vary in size. Usually, the width of the zone of catastrophic destruction is taken as the width of the hurricane. Often, the area of ​​storm force winds with relatively minor damage is added to this zone. Then the width of the hurricane is measured in hundreds of kilometers, sometimes reaching 1000 km. For typhoons, the destruction zone is usually 15 to 45 kilometers. The average duration of a hurricane is 9-12 days.

Hurricanes are one of the most powerful forces of the elements and, in terms of their detrimental effects, are not inferior to such terrible natural disasters as an earthquake. This is due to the fact that hurricanes carry enormous energy. Its amount released by a hurricane of average power for 1 hour is equal to the energy nuclear explosion at 36 gigatons.

The hurricane wind destroys strong and demolishes light structures, devastates sown fields, breaks wires and knocks down power transmission and communication poles, damages highways and bridges, breaks and uproots trees, damages and sinks ships, causes accidents on public energy networks in production. There are cases when a hurricane wind destroyed dams and dams, which led to large floods, threw trains off the rails, tore bridges off their supports, knocked down factory pipes, and threw ships onto land.

Hurricanes are often accompanied by heavy downpours, which are more dangerous than the hurricane itself, as they cause mudflows and landslides.

A tornado (tornado) is a violent atmospheric whirlwind that occurs in thunder cloud and extending to the surface of the earth (water) in the form of a dark giant sleeve - a “trunk”. Usually tornadoes begin like this: a thundercloud appears on the horizon, flooding the surrounding area with an unusual greenish light, humid heat builds up, and it becomes difficult to breathe. At first the wind picks up and it starts to rain. And suddenly the temperature drops sharply by 15 ° C. From the overhanging clouds, a giant “trunk” descends to the ground, rotating at a frantic speed, another whirlwind stretches towards it from the surface, similar to an overturned funnel. If they close, they form a huge pillar rotating counterclockwise.

A tornado over land is called a blood clot, in the USA - a tornado. Like hurricanes, tornadoes are identified by weather satellites. In Russia, tornadoes most often occur in the Central regions, the Volga region, the Urals, Siberia, on the coast and water areas of the Black, Azov, Caspian and Baltic Seas. Statistics registered tornadoes near the cities of Arzamas, Murom, Kursk, Vyatka and Yaroslavl.

It is extremely difficult to predict the place and time of the appearance of a tornado, therefore, for the most part, they arise suddenly for people, and it is all the more impossible to predict their consequences.

The main cause of these phenomena is cyclonic activity in the atmosphere - the processes of occurrence, evolution (development) and movement of large-scale disturbances in the fields of atmospheric pressure and wind - cyclones and anticyclones.

A cyclone (from Greek - whirling, rotating) is a strong atmospheric disturbance, a circular vortex movement of air with reduced pressure in the center. The diameter of the cyclone reaches from 100 to 2000 - 3000 km. In cyclones, whirling hurricane winds blow counterclockwise in the northern hemisphere of the Earth and clockwise in the southern hemisphere. In an anticyclone, the opposite is true, its speed is lower and the weather is better.

The cyclone itself moves rather slowly: 20-40 km/h, rarely up to 100 km/h. Tropical cyclones (typhoons) move somewhat faster. But inside the cyclone, the speed of wind eddies can be both storm and hurricane, that is, more than the speed of movement of the cyclone (typhoon) itself. Therefore, when they say: “a cyclone (typhoon) hit at a speed of 120 km / h,” this is not an entirely accurate expression. It would be more correct to say that the wind speed within the boundaries of the cyclone (typhoon) reached 120 km/h.

2. Measures to ensure safety in the event of a threat of storms, hurricanes, tornadoes.

Measures to ensure safety in the event of a threat of storms, hurricanes, tornadoes can be divided into three groups according to the time of their adoption:

1. early warning measures;
2. operational protective measures taken after the announcement of an unfavorable forecast, immediately before a hurricane (storm, tornado); Natural emergencies are divided into geological, meteorological, hydrological, natural fires, biological and space.

In December 1944, 300 miles east of about. Luzon (Philippines) ships of the US Third Fleet were in the hurricane zone. As a result of its impact, over 800 people died, 3 destroyers sank, 2 other ships were damaged, 146 aircraft on aircraft carriers were washed overboard or damaged.

Hurricanes, storms and tornadoes are wind meteorological phenomena.

Wind is the movement of air relative to the earth's surface, resulting from an uneven distribution of atmospheric pressure and directed from high pressure to low pressure.

It is characterized by direction and speed (strength). Direction is determined by the azimuth of the side of the horizon from which the wind is blowing, and is measured in meters per second (m/s), kilometers per hour (km/h), knots, or approximately Beaufort points.

The Beaufort scale is used to express the strength of the wind in points according to visual assessment. It was adopted by the World Meteorological Organization in 1963.

The main cause of a hurricane, storm and tornado is the cyclical activity of the atmosphere.

The cyclone is mobile atmospheric vortex with a diameter of one hundred to several thousand kilometers, which is characterized by a system hurricane winds blowing counterclockwise in the northern hemisphere of the Earth and clockwise- in the south.

Depending on the origin, cyclones are divided into tropical and extratropical.

The immediate cause of tropical cyclones is the condensation of steam in a vast layer humid air over the ocean with the release of a huge amount of energy, extratropical - significant contrasts in temperature and pressure adjacent air masses.

All cyclones have the same structure. The central part of the cyclones, which has the lowest pressure, light clouds and light winds, is usually called the "eye of the storm" ("eye of the hurricane"). The outer part, in which the maximum pressure and hurricane speeds of rotation of air masses are usually observed, is the wall of the cyclone. This wall is abruptly replaced by a peripheral part, where the atmospheric pressure decreases and the winds gradually weaken.

The speed of movement of cyclones is very different. Its average value for tropical cyclones is 50-60 km/h, and the maximum is 150-200 km/h. The speed of extratropical cyclones averages 30-40 km/h, and sometimes reaches 100 km/h. Atlantic cyclones are commonly referred to as hurricanes, while western tropical cyclones Pacific Ocean - typhoons.

Hurricane (typhoon)- a wind of enormous destructive force, having a speed of over 30 m/s, or 12 hulls on the Beaufort scale.

Hurricanes are also divided into tropical and extratropical hurricanes depending on the location of cyclones.

The most important characteristic of a hurricane is the wind speed. Long-term meteorological observations show that wind speed during hurricanes reached 30-50 m/s in most regions of the European part of the Russian Federation, and 60-90 m/s or more in the Far East.

Important characteristics of hurricanes are also the width and duration of action, the speed of movement and the path of movement.

The width of the zone of catastrophic destruction is usually taken as the width of the hurricane. This zone for tropical hurricanes has a width of 20 to 200 km or more. Extratropical hurricanes are characterized by a much greater width of their action, which can be several thousand kilometers.

The duration of the existence of a hurricane on average reaches 9-12 days or more.

The paths of tropical hurricanes are predominantly meridional, while those of extratropical hurricanes are mainly from west to east.

Hurricanes occur at any time of the year, but the vast majority of them pass through the territory of the Russian Federation in August and September. The timing of their passage has a certain cyclicity, which contributes to their more accurate forecasting. For the convenience of monitoring the movement of hurricanes and in order to reduce errors in the transmission of information, forecasters assign them short, easy-to-remember female or male names or use four-digit numbering.

Hurricanes are accompanied by such phenomena as showers, snowfalls, hail, electrical discharges. Hurricane winds often lead to dust and snow storms.

Storm (storm)- very strong wind with a speed of more than 20 m/s, which causes great destruction on land and waves at sea. Storms are characterized by lower wind speeds than hurricanes, and the duration of their action is up to several days.

Depending on the time of year, their formation and involvement in the air of various compositions of particles, dusty, dustless, snow and squall storms are distinguished.

Dust (sand) storms are accompanied by the transfer of large amounts of soil and sand. They arise in desert, semi-desert and plowed steppes and are capable of carrying millions of tons of dust over hundreds and even thousands of kilometers. Such storms are observed mainly in summer, during dry winds, sometimes in spring and in snowless winters. In the steppe zone, they usually occur during irrational plowing of land. In the Russian Federation, the northern boundary of the distribution of dust storms passes through Saratov, Samara, Ufa, Orenburg and the foothills of Altai.

Dust-free storms are characterized by the absence of dust entrainment into the air and a relatively smaller scale of destruction and damage. However, as they move further, they can turn into dust or snow storms, depending on the composition and condition of the surface layer of the earth and the presence of snow cover.

Snow storms are also characterized by significant wind speeds, which contribute to the movement of huge masses of snow through the air in winter. Their duration varies from several hours to several days. They have a relatively narrow band of action (from several kilometers to several tens of kilometers). Snow storms of great strength occur on the plains of the European part of the Russian Federation and in the steppe part of Siberia.

Squall storms are characterized by an almost sudden onset, just as quick an end, a short duration of action, and great destructive power. These storms are widespread throughout the European part of Russia, both in marine areas (here they are called squalls) and on land.

Tornado (tornado)- atmospheric vortex that originates in a thundercloud and often propagates to the surface of the earth. It has the form of a pillar, sometimes with a curved axis of rotation, with a diameter of tens to hundreds of meters with funnel-shaped extensions at the top and bottom. The air in a tornado rotates counterclockwise at a speed of up to 100 m/s and simultaneously rises in a spiral, drawing in dust, water and water from the ground. various items. Tornadoes exist for a short time - from several minutes to several hours, during which time they travel from hundreds of meters to several tens of kilometers.

Tornadoes are divided according to their structure into dense (sharply limited) and vague (indistinctly limited). According to time and spatial impact, they are subdivided into small tornadoes of short action (up to 1 km), small ones (up to 10 km) and tornadoes - hurricane whirlwinds (more than 10 km).

A tornado is almost always clearly visible, with its approach a deafening rumble is heard. The average speed of its movement is 50-60 km/h.

Tornadoes are observed in all regions of the globe. In Russia, tornadoes most often occur in the Volga region and Siberia, in the Urals and the Black Sea coast.

Consequences of hurricanes, storms and tornadoes. Hurricanes, storms and tornadoes are among the most powerful forces of the elements and are often comparable to an earthquake in their destructive effect. They cause significant destruction, cause great damage to the national economy, and lead to human casualties.

The main indicator that determines the destructive effect of hurricanes, storms and tornadoes is the velocity pressure of air masses, which determines the force of dynamic impact and has a propelling effect.

Hurricane wind damages strong and demolishes light buildings, breaks wires of power lines and communications, devastates fields, breaks and uproots trees.

People who have fallen into the hurricane zone are defeated due to their airlift (thrown), blows by flying objects, blows and crushing by collapsed structures.

Buildings collapsing under the influence of hurricanes crush those in them. As a result, people die, get injuries of varying severity and concussion.

Possible destruction of buildings and structures during hurricanes and tornadoes is divided into complete, strong and weak.

With complete destruction, only the foundations and basements of buildings, as well as buried structures and shelters, are preserved. Such objects are not subject to subsequent restoration and use. Such destruction is rare.

Severe destruction is characterized by the collapse of the walls of the upper floors. The lower floors and underground rooms of buildings are preserved. Engineering networks are broken or deformed.

The possibility of restoring such objects is associated with their restructuring.

With moderate destruction, the strong structures of structures (walls, ceilings, stairs) are preserved. Possible damage to engineering networks at the joints. Objects with such damage are restored in full.

Weak destructions include the deformation of light outbuildings, window and door frames, cornices and roofs. Partitions and plaster walls inside the buildings are damaged. With such minor damage, the restoration of the premises is carried out, as a rule, during the operation of the structures.

A hurricane, passing over the ocean, forms powerful clouds, which are sources of catastrophic downpours that cause flooding not only in coastal areas, but also in large areas of the continent. Heavy rainfall that accompanies hurricanes is also the cause of natural phenomena such as mudflows and landslides.

A common secondary consequence of a hurricane is fires resulting from accidents in power supply systems, leakage of flammable substances, violations of the localization of fire sources at work and at home.

Storms (storms), due to the fact that their characteristic wind speeds are much less than those of hurricanes, lead to much less destructive consequences. However, if they are accompanied by the transfer of sand, dust or snow, significant damage to agriculture, transport and other industries is possible.

Dust storms cover fields, settlements and roads with a layer of dust and sand, sometimes reaching several tens of centimeters, over areas of hundreds of thousands of square kilometers. Under such conditions, the harvest is significantly reduced or completely lost, and large expenditures of effort and money are required to clean up settlements, roads and restore agricultural land.

Snow storms (blizzards) in our country often reach great strength over vast expanses. Their consequence is the cessation of traffic in cities, rural areas and on the roads, the death of farm animals and even people. Such situations disrupt the rhythm of production throughout the country and require significant expenditure of manpower and resources for restoration work, especially on railways and roads.

Strong winds at low temperatures air contribute to the emergence of such hazardous meteorological phenomena like ice, frost and frost. As a result, failure of overhead power lines and communications, contact networks of electrified transport, antenna mast and other similar structures is possible.

Thus, hurricanes and storms, dangerous in themselves, are characterized by destruction and casualties.

A tornado, in contact with the earth's surface, often causes destruction of the same degree that occurs during strong hurricane winds, but on much smaller areas. These destructions are associated with the action of rapidly rotating air and a sharp rise of air masses upwards. As a result, some objects (cars, light houses, roofs of buildings, people and animals) can get off the ground and be transported hundreds of meters, which causes their destruction: people get injured and contused, and sometimes die. At the same time, significant indirect injuries to people are observed due to the involvement of a huge number of objects into the air.

A storm, a tornado are manifestations of the forces of nature that are very common throughout the world, which are related to wind phenomena.

Wind- this is the movement, the movement of air parallel to the earth's surface, resulting from the uneven distribution of heat and atmospheric pressure and directed from a high pressure zone to a low pressure zone.

The wind is characterized by direction, speed and strength. The direction is determined by the azimuth of the side of the horizon from which it blows, and is measured in degrees. Wind speed is measured in meters per second (m/s), kilometers per hour (km/h), knots (miles per hour). The strength of the wind is often measured in terms of speed, which makes it easier to perceive and understand these quantities. There is a special scale developed in 1806 by the English Admiral F. Beaufort, which allows you to very accurately assess the strength of the wind in points (from 0 to 12) by its effect on ground objects or by waves at sea (see Table 1).

Hurricane- this is an extremely fast and strong, often of great destructive power and considerable duration, air movement.

A hurricane occurs suddenly in areas with a sharp drop in atmospheric pressure. The speed of the hurricane exceeds 33 m/s. It is one of the powerful forces of the elements and in its detrimental effect can be compared with an earthquake.

A hurricane can capture an area up to several hundred kilometers in diameter and is capable of moving for thousands of kilometers. At the same time, the hurricane wind destroys strong and demolishes light buildings, devastates fields, breaks wires, knocks down communication and power lines, breaks and uproots trees, sinks ships, damages highways and bridges. Hurricanes are accompanied by heavy rains, causing flooding and destruction of buildings and structures.

On fig. Figure 2 shows the aftermath of one of the hurricanes that passed by.

Rice. 2. The aftermath of a passing hurricane

Storm- it is a downpour, accompanied by a strong wind of a squally nature, which can easily cause a flood in a river, a flood or a mudflow. It also causes considerable damage due to the strong wind pressure.

Tornado(Fig. 3) is an ascending vortex of rapidly rotating air that looks like a dark column with a diameter of several tens to hundreds of meters with a vertical, sometimes curved axis of rotation.

Rice. 3. Tornado

A tornado is formed in clear weather when large air masses collide. When the air is warm at the bottom, it naturally rises, and if a hurricane blows in, the warm air current swirls. The tornado, as it were, "hangs" from the continental cloud in the form of a giant rotating funnel. The air rotates in the column counterclockwise at a speed of up to 100 m/s. In the internal cavity of the tornado, the pressure is always reduced, so any objects that are in the way of its movement are sucked in there. A tornado moves above the ground at an average speed of 50-60 km/h.

Strong tornadoes travel tens of kilometers and tear off roofs, uproot trees, lift cars into the air, scatter telegraph poles, and destroy houses. If you don’t take cover from a strong tornado in time, it can lift and throw a person from a height of the 10th floor, bring down flying objects, debris, crush him in the ruins of a building.

Upon receipt of information about an impending hurricane, storm or tornado, it is necessary to immediately begin to carry out preventive work: strengthen insufficiently strong structures at construction sites and loading areas, in ports, close doors, dormer openings and attic spaces in buildings, sheathe windows and shop windows with boards or close them with shields , and seal the glass with strips of paper or cloth or, if possible, remove it. At the same time, it is advisable to leave the doors and windows on the leeward side open, securing them in this position in order to balance the external and internal pressure in the building. From roofs, balconies, loggias and window sills, it is necessary to remove things that, if dropped, can cause injury to people. Items located in the yards must be secured or brought into the room. It is also advisable to take care of emergency lamps - electric lamps, kerosene lamps, candles. It is also recommended to create stocks of water, food and medicines, especially dressings.

During a hurricane, storm or tornado, one should beware of injuries from fragments of flying glass, slate, roofing iron, shop windows, billboards and other objects. At the same time, shelters, basements, cellars, undergrounds are the safest place during a storm, hurricane or tornado. If a hurricane or a tornado caught you in an open area, it is best to take cover in a ditch, pit, ravine, any recess: lie down on the bottom of the recess and cling tightly to the ground.

Do not go outside immediately after the wind weakens, as a gust of wind may repeat in a few minutes. If you still need to go outside, then you should stay away from buildings and structures, high fences, poles, trees, masts, supports, billboards. Particular attention should be paid to broken electrical wires, since it is possible that they are energized.

The main thing in these conditions is not to panic, to act competently, confidently and reasonably, to prevent oneself and keep others from unreasonable acts, to provide assistance to the victims.

The main types of damage to people during hurricanes, storms and tornadoes are closed injuries of various areas of the body, bruises, fractures, concussions, wounds accompanied by bleeding.

A storm often precedes thunderstorm— strong electrical lightning discharges (Fig. 4). To avoid the risk of being hit by it, you must behave as follows:

• don't stand in front of open window do not hold metal objects in your hands;
• do not hide under trees, especially under oaks and larches;

Rice. 4. Electric lightning discharge

During a thunderstorm it is forbidden:

• be in wet clothes.

During a thunderstorm, the wind will not give a correct idea of ​​the direction of the thunderstorm, thunderstorms often go against the wind. The distance to a thunderstorm can be determined by the time between a flash of lightning and a roll of thunder (1 s - distance 300-400 m, 2 s - 600-800 m, 3 s - 1000 m). Just before the start of a thunderstorm, there is usually a calm, or the wind changes direction. During a thunderstorm in the forest, it is preferable to hide among low trees, in the mountains - 3-8 m from a high "finger" 10-15 m high, in an open area - in a dry hole, ditch.

An effective means of ensuring the safety of people, protecting buildings and structures, equipment and materials from explosions, fires and destruction, possible when exposed to lightning, is the use of rod or wire lightning rods.

Actions during a hurricane and a storm

What to do if there is a storm warning? First of all, listen carefully to the instructions of the Civil Defense and Emergency Situations headquarters. They will report the estimated time and strength of the hurricane, recommendations for the use of shelters and evacuation. Then take personal protective measures:

• on the windward side of the building, tightly close windows, doors, attic hatches and ventilation openings; paste over window glass, but protect it with shutters or shields; to equalize the internal pressure, on the leeward side of the door and window, open and secure in this position;
• prepare an autonomous supply of water and food, medicines; take a flashlight, a kerosene lamp, a candle, a camp stove, a kerosene stove, a battery-operated receiver; take documents and money with you;
• remove things from balconies, window sills and loggias that can be captured by the air flow; the same applies to objects in the yard or on the roof;
• put out the fire in the stoves, prepare to turn off the power grid, close the gas valves;
• leave radios and televisions on (important information may be received through them);
• move from light buildings to more durable or GO shelters.

Children from kindergartens and schools must go home, all events are canceled. If the storm warning comes too late, the children are housed in basements or in the central part of the buildings.

It is best to wait out a hurricane in a shelter, a pre-prepared shelter, or at least in the basement. If you have to wait for the onset of a natural disaster in a building, you need to choose the safest place - in the middle of the house, in the corridors, on the ground floor. Shards of flying windows can hurt, so you should stand in the wall, close to the wall, hide in a built-in closet or protect yourself with mattresses.

If during a hurricane or storm a person was on the street, you need to be as far away from buildings as possible and hide in a ditch, pit, ditch, clinging tightly to the ground. This will save you from flying fragments, objects, torn off road signs and bricks - the most likely sources of danger. Of course, if there is an opportunity to be in the shelter or the basement of the nearest building, then you need to do it as quickly as possible.

Large structures - bridges, overpasses, pipelines - must be avoided at all costs. It must be borne in mind that man-made disasters and fires are a common result of natural disasters, so it is better to stay away from chemical or oil refineries, various high-risk facilities and power lines. By the way, a defeat by atmospheric electricity is also possible, since a thunderstorm often comes along with a storm.

When the wind has died down, you should not immediately go outside: in a few minutes the squall may repeat. Then, when it becomes clear that the hurricane has ended, leaving the house, you should look around - if there are any hanging objects and parts of structures, broken wires, pipelines. Is there a smell of gas. The fire must not be lit until it is certain that there was no leakage. You can't use elevators either.

On the street, one must stay away from buildings, poles, high fences, masts, etc. It should be remembered that after a natural disaster, a state of emergency can be introduced in the city, and citizens are obliged to comply with all orders of representatives of the Committee on Affairs civil defense and emergency situations.

Bursus is often preceded by a thunderstorm, strong electrical discharges of lightning. To avoid the risk of being hit by it, you must behave as follows:

• turn off the TV and other electrical appliances;
• do not stand in front of an open window, do not hold metal objects in your hands;
• close windows and doors, because the air flow is a good conductor of electric current;
• remember that the middle of the room is the safest place;
• being outdoors, never run, stop the car;
• do not hide under trees, especially under oak and larch;
• move from high ground to low ground;
• stay away from metal structures, pipes and water surfaces.

During a thunderstorm it is forbidden:

• lean against rocks and sheer walls;
• stop at the edge of the forest;
• walk and stop near water bodies;
• hide under a rocky canopy;
• move in a tight group;
• be in wet clothes.

During a thunderstorm in the forest, it is preferable to hide among low trees, in the mountains 3-8 m from the high "finger" 10-15 m, in open areas - in a dry hole, ditch.

One type of hurricane -blizzard. It can last for several days, but even in a few hours a blizzard can seriously disrupt the life of the fool. At this time, you can leave the house only in exceptional cases and never alone. It is necessary to tell the neighbors where the person is going and when he will return.

In a car, you can only move on big roads and highways. If orientation is lost, you must not move away from the machine out of sight. And it is better to wait out a snow storm in the nearest settlement.

Recall that the atmosphere is the lightest and most mobile shell of the Earth.

The situation in the atmosphere is constantly changing. The temperature of the air, its pressure and humidity are changing, the movement of air masses relative to the surface of the Earth is constantly taking place. Movement in the atmosphere occurs under the influence of solar energy, the force of gravity and the rotation of the Earth. Air masses are formed above the Earth's surface, which have certain characteristics (temperature, pressure, humidity).

Depending on the place of formation of air masses, their properties are different. The interaction of air masses with different properties leads to the formation of various meteorological phenomena that determine the weather. Weather is the state of the atmosphere in this place and in this moment time.

A change in air pressure causes air to move - wind. Air moves from an area of ​​high pressure to an area of ​​low pressure. Depending on the pressure difference, the speed of air movement (wind speed) is also determined. It can be different: from a light breeze (1 - 3 m/s) to a hurricane (more than 30 m/s).

The most dangerous natural phenomena meteorological origin connected with high speed movement of air masses. These are hurricanes and storms that lead to emergencies. In terms of the number of victims of their consequences, hurricanes and storms rank third among natural emergencies, and second in terms of material damage.

The cause of hurricanes and storms is the formation of cyclones in the atmosphere. The speed of the hurricane is determined by the speed of the cyclone. (Note: cyclones that originate in the Atlantic Ocean are called hurricanes, and cyclones that originate in the western Pacific Ocean are called typhoons.)

Hurricane- this is a wind of enormous destructive force, having a speed of more than 30 m / s. Long-term meteorological observations show that the wind speed during hurricanes reached 30-50 m/s in most regions of the European part of Russia, and Far East- 60-90 m/s and more.

Distribution of average pressure and air currents in the atmosphere for northern hemisphere: A - at an altitude of 10 km; B - at the earth's surface; H - low pressure; AT - high pressure; 1 - isobars; 2 - wind direction

Cold front in section

Storm- this is a wind whose speed is less than the speed of a hurricane, it reaches 15-20 m / s. (Note that a short-term wind increase to a speed of 20-30 m/s is called a squall.)

Cyclone is a powerful atmospheric vortex with reduced atmospheric pressure in the center. The diameter of the cyclone reaches from 100 km to several thousand kilometers.

All cyclones have the same structure. The central part of the cyclone has the lowest pressure and weak winds, it is called the "eye of the storm"; the outer part has the maximum pressure and the most strong winds, it is called the "wall of the cyclone."

The speed of movement of cyclones is different. The average speed for tropical cyclones is 50-60 km/h (13-16 m/s) and the maximum speed is 150-200 km/h (42-55 m/s). The speed of extratropical cyclones averages 30-40 km/h (8-11 m/s), and sometimes 100 km/h (27 m/s).

Depending on the place of origin, cyclones are divided into tropical and extratropical.

Tropical cyclones are called those that occur in tropical latitudes, and extratropical - in extratropical latitudes.

Tropical cyclones are the "carriers" of the most destructive hurricanes, as they have a greater speed of movement. Tropical cyclones originate over oceans at low latitudes from 10 to 20° in both hemispheres. Most of them are formed in the northern part of the tropical Atlantic and the southwestern part of the Pacific Ocean.

Hurricane winds in a cyclone can occur at any time of the year, but the vast majority of cyclones passing through the territory of Russia fall in August - September.

Hurricanes and storms cause significant destruction, cause great material damage, and lead to human casualties. Hurricane wind damages strong and demolishes light buildings, breaks wires of power lines, breaks and uproots trees. People caught in the hurricane zone may die or be injured of varying severity.

Hurricanes are often accompanied by heavy downpours, which can cause mudflows and floods. In 1973, a typhoon that originated in the Sea of ​​Japan swept over Japan and then over the Primorsky Territory. For three days of continuous rain in Vladivostok, more than half of the annual rainfall fell. In July 1989, a powerful typhoon Juddi passed from the south to the north of the Far Eastern Territory at a speed of 165 km/h. The typhoon was accompanied by heavy rainfall. As a result, 109 settlements, in which up to 2 thousand houses were damaged. 8,000 people were evacuated from dangerous areas. There were human casualties.

At the end of December 1999, a hurricane swept across Europe. As a result of the hurricane, France was badly damaged, 87 people died, 8 were missing. The roofs of many houses were demolished, the power transmission system was disrupted (3.5 million families were left without electricity). In the Versailles park, 10 thousand trees were destroyed.

Aftermath of the hurricane in Paris. Heavy wind (180 km per hour) tore roofs off houses and uprooted ancient trees. 30 people died. December 1999

What determines the destructive effect of hurricanes and storms? The main indicator that determines the destructive effect of these natural disasters is the velocity pressure of air masses.

The Beaufort scale is used to determine the strength of the wind at the Earth's surface.

Francis Beaufort (1774-1857), an English military hydrographer and cartographer, rear admiral, in 1806 proposed to estimate the strength of the wind by its effect on ground objects and by the waves of the sea; for this, he developed a conditional 12-point scale.

AT Russian Federation hurricanes most often occur in the Primorsky and Khabarovsk Territories, on Sakhalin, Kamchatka, Chukotka and the Kuril Islands.

Beaufort wind scale

We have already noted that hurricanes and storms can occur on the territory of Russia at any time of the year. Forecasters classify hurricanes and storms as extreme events with a moderate propagation speed. Therefore, it is possible to announce a storm warning in advance and prepare for a natural disaster in order to reduce its negative consequences.

Test yourself

1. Describe natural disasters - hurricanes and storms, their causes, possible consequences.
2. What causes the destructive power of hurricanes and storms?

After lessons

In the safety diary, write down 2-3 examples of hurricanes and storms that took place on the territory of Russia, describe their consequences. Explain the reason for their occurrence. Find examples in the media or on the Internet.

Workshop

You are caught outside in a snow storm. What are your personal safety measures? Justify your answer.