How does a tornado appear? What is the natural phenomenon of a tornado?

Tornadoes, or, as they are called on the American continent, tornadoes, are one of the most mysterious and destructive natural phenomena. This is an atmospheric vortex that occurs in a rain or thundercloud. It looks like a cloud funnel, spreads with incredible speed and is capable of causing considerable destruction. Today we will talk about the most incredible tornadoes in the history of mankind! So it will be interesting!

State of Texas, USA

The most powerful tornado, which had simply incredible wind speed and was listed in the Guinness Book of Records, was recorded in the USA in the town of Wichita Falls, Texas on April 2, 1958. The maximum wind speed was 450 km/h. The town through which the tornado “passed” was completely destroyed, houses were lifted into the air, and some objects were transported over a huge distance. The tornado killed 7 people and injured 100. Damage from natural disaster amounted to 15 million dollars.

East Pakistan

The tragedy occurred in 1969, when the city of Dhaka was part of East Pakistan (now Bangladesh). The tornado struck the northeastern outskirts of the city. As a result, about 660 people died and a total of 4,000 were injured. Moreover, on that day, two tornadoes passed through the territory of modern Bangladesh. The second tornado swept through Homna Upazila - Comilla region. These tornadoes were part of the same storm system, but after forming, they separated. The second tornado killed 223 people.

Oklahoma

On May 20, 2013, a devastating tornado swept over the American state of Oklahoma. The storm cut a strip 3 km wide and 27 km long. The hardest hit was Moore, a suburban town of about 56,000. Large swaths of the town were virtually wiped out. The wind speed reached 267 km/h. The tornado lasted for a full 40 minutes. As a result of the disaster, 24 people died. More than 230 people were injured.

Yangtze, China

Over the past decades, humanity has learned to predict the occurrence of tornadoes, build reliable structures for protection, and quickly evacuate in the event of a disaster. But June 2015 demonstrated that, despite all the achievements, man is still defenseless against the power of nature. A river cruise ship was caught by surprise by a terrible tornado, costing the lives of 442 passengers. Fortunately, the other ships were warned of the approaching hurricane and were not damaged.

Tri-State Tornado

The third deadliest tornado in human history to hit the United States was the Tri-State Tornado. This happened in 1925. The tornado had the highest rating on the Fujita scale - F5 and spawned eight more similar monsters. As the name suggests, on March 18, 1925, this tornado struck three states at once.

The main blow was struck in Missouri, then the hurricane moved to Illinois and completed its deadly march in Indiana. But Alabama, Tennessee, Kentucky and Kansas were also among the states affected. As a result, 695 people died, more than 2,000 were injured, and 50,000 people were left homeless. The tornado lasted 3.5 hours, and the average speed of the funnel was 100 km/h.

Madarganj – Mrizapur

In 1996, a tornado collected its bloody sacrifice in areas from Madarganj to Mrizapur. Moreover, no preparations and calculations of scientists could prevent the death of 700 people and the destruction of more than 80,000 houses. The number of people injured in this tornado remains unknown, but the death toll makes it the second deadliest tornado in human history.

Daulatpur-Salturia

It is difficult to find a country that has suffered the consequences of a tornado like Bangladesh. The Daulatpur-Salturia tornado is considered the deadliest and most destructive hurricane ever. written history humanity. The disaster on April 26, 1989 killed about 1,300 people in just a few minutes. A giant crater hits Manikganj, a densely populated area of Bangladesh.

Before the tornado hit, the country had been suffering from drought for six months, a factor that scientists believe contributed to the tornado's formation. It is not surprising that the tornado, 1.5 kilometers wide, completely destroyed everything in its path. As a result, about 12,000 people were injured and a total of 80,000 were left homeless.

What is a tornado (tornado)?

A tornado (or tornado) is a vortex in the atmosphere, developing inside a cumulus cloud, and gradually descending to the ground in the form of a column up to 400 m wide at the base. In some cases, its diameter on land can reach up to 3 km, and on In water this value is usually no more than 30 m.

There is a huge difference in pressure between the inside and outside of a tornado - it can be so great that objects falling inside (including houses) are simply torn apart. This area of highly rarefied air, just like in a syringe, when you pull the plunger, which causes water, sand and other various objects to be sucked into the vortex, which sometimes fly apart or are transported over very long distances.

Why does a tornado occur and what is it?

The causes of the tornado could not be reliably determined. However, tornadoes are believed to occur when warm, moist air comes into contact with a cold, dry “dome” that appears over cold areas of land or ocean. Upon contact, heat is released, after which the heated air rises, thereby creating a rarefaction area.

Warm air from the cloud and underlying cold air are drawn into this zone, as a result, significant energy is released and a funnel is formed. The speed of air movement in it, according to some estimates, can reach up to 1300 km/h, while the vortex itself moves on average at a speed of 20 to 60 km/h.

Types of tornadoes

The most common are whip-like, thin and smooth, similar in appearance to a whip or scourge.

Water - formed above the surface of oceans, seas, and in rare cases lakes

Earthen ones are rare; they are formed during destructive disasters or landslides

Snow - tornadoes formed during a severe snowstorm

Less often you can find vague ones, similar to thick clouds near the ground, and composite ones, which consist of two or three vortices

Fiery. During volcanic eruptions, as a result of a strong fire, fire tornadoes can often be observed, spreading fire over tens of kilometers

In deserts there are some kind of analogues of tornadoes - dust or sand whirlwinds, but usually their diameter does not exceed 3 meters

What's inside a tornado? Scientists' opinion

Tornadoes remain a poorly understood phenomenon to this day, but scientists believe that at the center of the tornado there is an area of low pressure that prevents outside air from filling the interior of the tornado. It is quite possible that there are vertical air currents inside, although this kind of phenomenon has not been reliably proven.

The suction force of a tornado can be explained by the high turbulence of the air column and the vertical component of the speed, which rapidly changes during movement.

Tornado Fury

The weather has by no means lost its ability to sow fear in people's hearts. Before the terrible power of the wind, the most destructive means of warfare will seem insignificant. Hurricanes sweep through coastal regions, destroying everything in their path; tornadoes mar the landscape. An unexpected gust of wind can throw the largest aircraft to the ground. With all the technologies available in our time, man is just as dependent on the mercy of the angry winds as his distant ancestor. The weather is not only almost unpredictable, but also has an inexhaustible supply of tricks and surprises.

At the epicenter of a tornado. Eyewitness account

The fury of a tornado is so unexpected and immense that survivors are rarely able to remember the details of what happened. But on May 3, 1943, retired Army Capt. Roy S. Hall was able to emerge with his family from the tornado's eye and gave a clear description of the twister that destroyed his home in McKinney, Texas, about 30 miles north of Dallas.

As the storm began, Hall locked his wife and children in the bedroom. And then the outer wall of the room collapsed inside with a terrible roar. However, the worst was yet to come. The piercing screech of the wind suddenly died down. “It was exactly like that,” Hall later wrote, “as if they had covered my ears with their palms, cutting off all sounds except the unusual ones.” strong blows pulse in the ears and head. I have never experienced such a feeling before.” And in this icy silence, the shuddering house was illuminated with a mysterious blue glow.

At the same moment, Hall was thrown 10 feet, and he found himself under the rubble of the wall so suddenly that he could not remember how he got there. He climbed out from under the rubble, hugged his 4-year-old daughter to him and waited for his house, which was no longer supported by its foundation, to be carried away. And at that time a terrifying vision appeared before him.

“The thing first made a wave-like movement from top to bottom, and then froze motionless, except for a weak pulsation up and down,” Hall later wrote. - It was a curved edge, concavely facing me; its lower contour was located almost horizontally... This was the lower end of the tornado. At this time we found ourselves in the tornado itself!”

Hall looked up. What he saw looked like an opaque wall with a smooth surface, about 4 meters thick, surrounding a columnar cavity. “It looked like the inside of an enamel riser,” Hall recalled. “It stretched upward for more than 300 meters, swayed slightly and slowly curved to the southeast. Below, at the bottom, judging by the circle in front of me, the funnel was about 50 m in diameter. Higher up it expanded and, apparently, was partially filled with a bright cloud, flickering like Fluorescent Lamp" The rotating funnel swayed, and Hall saw that the entire column seemed to be composed of many huge rings, each of which moved independently of the others and caused a wave that ran from top to bottom. When the crest of each wave reached the bottom, the top of the funnel made a sound like the cracking of a whip.

Hall watched in horror as the tip of the tornado touched down and destroyed a nearby house. According to Hall, “the house seemed to dissolve, various parts of it were carried away to the left, like sparks from an emery wheel.”

Soon the tornado continued its journey to the southeast. Hall's family managed to come out of the mess almost unscathed. At the cost of losing their home, they received from the “eye” of a furious storm a rare opportunity to look at the cruel riot of nature at the epicenter of its manifestations.

Atmospheric anomaly

For pilots and scientists at the US National Oceanic and Atmospheric Administration, flying into the eye (calm area) of a raging hurricane was part of their risky job tracking tropical storms. 1989, September 15 - The crew of NOAA-42, flying in Hurricane Hugo from the Ants Islands to Charleston, South Carolina, suffered more than they could have ever bargained for when their plane headed straight into the eye of the giant storm. .

As soon as the plane pierced the eye wall just a few hundred feet from the calm center of the storm, violent forces fell upon the plane, threatening to tear it apart. One of the four engines failed, and the brave Orion began to fall. They managed to level it out and return to the “eye” when only 200 m remained to the surface of the sea. Later, analyzing this terrible adventure, scientists came to the conclusion that the plane flew into a bizarre atmospheric anomaly - into a tornado, which could not be detected because Contrary to traditional meteorological ideas, he was in the wall of the “eye” of a large-scale storm and thereby was able to disguise his devilish power.

A tornado, whose twisting coils carry the fiercest winds on our planet, can destroy everything it touches in an instant. During the 18th and 19th centuries, more than a dozen times during the height of the day, the sky over New England turned black, and preachers prophesied that the end of the world was near. Fortunately, these so-called dark days were not harbingers of divine punishment, but the result of the vagaries of the weather.

Amazing cases from the life of a tornado

Tornadoes have become famous not only for their cruelty, but also for their eccentricities. Whirling winds reaching speeds of up to 200 mph can drive a straw into a tree trunk and cause a wood chip to pierce a steel sheet. Meanwhile, powerful internal vortices hidden in the tornado are apparently responsible for the fact that some objects are destroyed, while others remain unharmed. And rising air currents can serve as a cushion: there have been cases of people flying into the air only to then softly land on the ground in the middle of a furious storm.

Here are some of such cases:

The 1974 tornado that destroyed Xenia, Ohio, completely destroyed a farmer's home and everything in it, but spared two fragile items: a mirror and a box of Christmas decorations.

1965, April 11 - tornadoes ripped through large parts of the US Midwest. One in Cleveland, Ohio, lifted a teenager out of bed, carried him out the window and landed him, unharmed, on the other side of the street. At the same time, he remained wrapped in a blanket. Another tornado in Dunlop, Indiana, snatched an eight-month-old baby from a collapsing home and laid him on the ground nearby. In Grand Rapids, Michigan, a man was carried from his front porch to a pile of wood that was all that was left of his neighbor's house.

1958 June 10 - A woman was thrown from a window in Eldorado, Kansas. She successfully landed 20 meters from the house. A gramophone record with a recording of the song “Bad Weather” fell next to her.

1955, May 25 - In Udall, Kansas, a powerful gust of wind yanked Fred Dye out of his shoes and threw him into a tree, where he was able to ride out the storm. Not far from him, a husband and wife, emerging from the bedroom that had provided them with safety, discovered that all the other rooms of the house had been taken away.

Shortly after a tornado tore through Illinois on March 18, 1925, a page from Literary Digest fell to the ground. It contained a photograph and description of the 1917 tornado.

The surface of the water, for example, in the Yauza River and in the Lublin ponds, when a tornado passed, first boiled and began to seethe like in a cauldron, then the whirlwind sucked the water inside itself and the bottom of the reservoir and river was exposed!

The energy of an average tornado with a radius of one kilometer and an average speed of 250 km/h is equal to the energy of the world's first atomic bomb!

The most powerful and deadly tornadoes

The strongest tornado was recorded in 1999 in Texas (USA), when a powerful funnel swept across the ground at a speed of about 500 km/h and destroyed everything in its path.

If we talk about size, the 2013 tornado in Oklahoma can be considered the largest - it moved at a speed of 485 km/h and covered an area of about 4.2 km. In this whirlwind, one of the most famous tornado hunters, Tim Samaras, died along with his son and friend Carl Young.

The largest and most destructive tornado occurred on April 26, 1989 in the city of Shatursh (Bangladesh), which killed more than 1,300 people (it was included in the Guinness Book of Records as the most tragic).

1935, September 2 - during a tornado in Florida, wind speeds reached 500 km/h! This tornado killed 400 people and completely destroyed buildings in a strip 15–20 km wide.

Among the largest water tornadoes: in Massachusetts Bay, the tornado reached a height of more than 1000 m, and the diameter of the mother cloud was 250 m, and the diameter of the water was 70 m. The diameter of the cascade was 200 m, and the height was 150 m.

Description

Inside the funnel, the air descends and outside it rises, rotating rapidly, creating an area of very rarefied air. The vacuum is so significant that closed gas-filled objects, including buildings, can explode from the inside due to the pressure difference. This phenomenon increases the destruction from the tornado and makes it difficult to determine its parameters. Determining the speed of air movement in a funnel is still a matter of serious problem. Basically, estimates of this quantity are known from indirect observations. Depending on the intensity of the vortex, the speed of the flow in it can vary. It is believed that it exceeds 18 m/s and can, according to some indirect estimates, reach 1300 km/h. The tornado itself moves along with the cloud that generates it. This movement can produce speeds of tens of km/h, usually 20-60 km/h. According to indirect estimates, the energy of an ordinary tornado with a radius of 1 km and an average speed of 70 m/s is comparable to the energy of a standard atomic bomb, similar to the one that was exploded in the United States during the Trinity tests in New Mexico on July 16, 1945. (unavailable link) The record for the lifetime of a tornado can be considered the Mattoon tornado, which on May 26, 1917, covered 500 km across the United States in 7 hours and 20 minutes, killing 110 people. The width of the vague funnel of this tornado was 0.4-1 km; a whip-like funnel was visible inside it. Another famous tornado event is the Tristate tornado, which passed through Missouri, Illinois and Indiana on March 18, 1925, traveling 350 km in 3.5 hours. The diameter of its vague crater ranged from 800 m to 1.6 km.

In the Northern Hemisphere, air rotation in tornadoes usually occurs counterclockwise. This may be due to the directions of mutual movements of air masses on either side of the atmospheric front on which the tornado is formed. Cases of reverse rotation are also known. In areas adjacent to the tornado, air descends, causing the vortex to close.

At the point of contact of the base of the tornado funnel with the surface of the earth or water, a cascade- a cloud or column of dust, debris and objects raised from the ground or water splashes. When a tornado is formed, the observer sees how a cascade rises from the ground towards the funnel descending from the sky, which then covers the lower part of the funnel. The term comes from the fact that the debris, having risen to a certain insignificant height, can no longer be held by the air flow and falls to the ground. The funnel, without touching the ground, can envelop case. Merging, the cascade, the case and the mother cloud create the illusion of a tornado funnel that is wider than it actually is.

Sometimes a whirlwind formed at sea is called a tornado, and on land - a tornado. Atmospheric vortices, similar to tornadoes, but formed in Europe, are called blood clots. But more often all these three concepts are considered synonyms.

Reasons for education

The reasons for the formation of tornadoes have not yet been fully studied. It is possible to indicate only a few general information, most characteristic of typical tornadoes.

Tornadoes go through three main stages in their development. At the initial stage, an initial funnel appears from a thundercloud, hanging above the ground. Cold layers of air located directly below the cloud rush down to replace warm ones, which, in turn, rise upward (such an unstable system is usually formed when two atmospheric fronts connect - warm and cold). The potential energy of this system is converted into kinetic energy of the rotational movement of air. The speed of this movement increases, and it takes on its classic appearance.

The rotational speed increases over time, while in the center of the tornado the air begins to rise upward intensively. This is how the second stage of a tornado’s existence proceeds - the stage of a formed vortex of maximum power. The tornado is fully formed and moves in different directions.

The final stage is the destruction of the vortex. The power of the tornado weakens, the funnel narrows and breaks away from the surface of the earth, gradually rising back into the mother cloud.

The lifetime of each stage is different and ranges from several minutes to several hours (in exceptional cases). The speed of tornadoes also varies, on average - 40 - 60 km/h (in very rare cases it can reach 210 km/h).

Places of tornado formation

Places where tornadoes can form are orange on the map.

The second region of the globe where conditions for the formation of tornadoes arise is Europe (except for the Iberian Peninsula), and the entire European territory of Russia, with the exception of the south of Russia, Karelia and the Murmansk region, as well as other northern regions.

Thus, tornadoes are mainly observed in the temperate zone of both hemispheres, from approximately the 60th parallel to the 45th parallel in Europe and the 30th parallel in the USA.

Tornadoes are also recorded in the east of Argentina, South Africa, the west and east of Australia and a number of other regions, where there may also be conditions for collision of atmospheric fronts.

Classification of tornadoes

Scourge-like

This is the most common type of tornado. The funnel looks smooth, thin, and can be quite tortuous. The length of the funnel significantly exceeds its radius. Weak tornadoes and tornado funnels that descend into the water are, as a rule, whip-like tornadoes.

Vague

They look like shaggy, rotating clouds that reach the ground. Sometimes the diameter of such a tornado even exceeds its height. All funnels large diameter(more than 0.5 km) are vague. Usually these are very powerful vortices, often composite. Causes enormous damage due to large sizes and very high wind speeds.

Composite

May consist of two or more separate blood clots around a main central tornado. Such tornadoes can be of almost any power, however, most often they are very powerful tornadoes. They cause significant damage over large areas. .

Fiery

These are ordinary tornadoes generated by a cloud formed as a result of a strong fire or volcanic eruption. It was precisely such tornadoes that were first artificially created by man (experiments by J. Dessens in the Sahara, which continued in 1960-1962). They “absorb” tongues of flame that stretch towards the mother cloud, forming a fiery tornado. A fire can spread tens of kilometers. They can be whip-like. Cannot be fuzzy (fire is not under pressure, like whiplash tornadoes.

Water

These are tornadoes that formed over the surface of oceans, seas, and in rare cases, lakes. They “absorb” water (why? See above) and form waterspouts. They “absorb” waves and water, forming, in some cases, whirlpools that stretch towards the mother cloud, forming a waterspout. They can be whip-like. Cannot be fuzzy (like fire tornadoes: the water is not under pressure, like a whip-like tornado).

Earthen

These tornadoes are very rare, they are formed during destructive cataclysms or landslides, sometimes earthquakes above 7 points on the Richter scale, very high pressure drops, and very thin air. A whip-like tornado, located with a “carrot” with its thick part towards the ground, inside a dense funnel, a thin stream of earth inside, a “second shell” of earthen slurry (if there is a landslide). In the case of earthquakes, it lifts stones, which is very dangerous.

Ball

It is not yet known how it is “structured”. It has not yet been proven that it exists. It can be fire, water, earth, air, and, most dangerously, gas, which causes explosions like ball lightning. In general, this is a voluminous oval or ball that spins at breakneck speed, then flattens out, flattening all its contents (if a person gets in there, it will look like a thick pancake, or torn into pieces). I was in Brazil during a fire tornado, but due to its small size (they are about 10 - 50 meters in diameter) they did not notice it.

Snowy

These are snow tornadoes during a severe snowstorm.

Sand whirlwinds

It is necessary to distinguish from the considered tornadoes the sand “tornadoes” (“dust devils”) observed in deserts (Egypt, Sahara); unlike the previous ones, the latter are sometimes called thermal vortices. Similar in appearance to real tornadoes, desert sand whirlwinds have nothing in common with the former either in size, origin, structure or action. Arising under the influence of local heating of the sandy surface by the sun's rays, sand vortices are a real cyclone (barometric minimum) in miniature. A decrease in air pressure under the influence of heating, causing an influx of air from the sides to the heated place, under the influence of the rotation of the Earth, and even more so - the incomplete symmetry of such an upward flow, forms a rotation that gradually grows into a funnel and sometimes, under favorable conditions, takes on quite impressive dimensions. Carried away by the vortex movement, the masses of sand are lifted by an upward movement in the center of the vortex into the air, and thus a sand column is created, which resembles a tornado. In Egypt, such sand whirlwinds up to 500 and even 1000 meters high with a diameter of up to 2-3 meters were observed. When there is wind, these vortices can move, carried away by the general movement of air. After holding on for some time (sometimes up to 2 hours), such a vortex gradually weakens and crumbles.

Damaging factors

Tornado Precautions

It is necessary to take shelter in the strongest reinforced concrete structure with a steel frame, keeping close to the strongest wall, also - best option shelter - an underground shelter or cave. Staying in a car or trailer, given the high lifting force of a tornado, is mortally dangerous; it is also life-threatening to encounter the elements outdoors.

If a tornado finds a person in an open space, then you need to move with maximum speed perpendicular to the apparent movement of the funnel. Or, if retreat is impossible, take cover in depressions on the surface (ravines, holes, trenches, road ditches, ditches, ditches) and press yourself tightly to the ground, face down, covering your head with your hands. This will help significantly reduce the likelihood and severity of injuries from objects and debris carried by the tornado.

In a small one- or two-story private house, you can use the basement (here for a similar Emergency It’s wise to place a supply of water and canned food in advance, as well as candles or LED lamps), if there is no basement, then you should stay in the bathroom or in the center of a small room on the ground floor, perhaps under solid furniture, but away from windows. It would be prudent to dress in thick clothes, taking money and documents with you. To prevent the house from exploding from the pressure drop caused by the air being pumped into the whirlwind, it is recommended to tightly close all windows and doors on the side of the approaching tornado, and on the opposite side, open them wide open and secure them. According to safety precautions, it is advisable to turn off the gas and turn off the electricity.

Interesting facts from the chronicle of tornadoes

Current Research

Literature

Varaksin A. Yu., Romash M. E., Kopeytsev V. N. Tornado. - M.: Fizmatlit, 2011. - 344 p. - 300 copies. - ISBN 978-5-9221-1249-9

Notes

Soviet encyclopedic dictionary. - M.: “ Soviet Encyclopedia", 1981. - 1600 p.
Nalivkin D.V. Tornadoes. - M.: Nauka, 1984. - 111 p.
“Tornado” // Etymological Dictionary of the Russian Language. / comp. M. R. Vasmer, - M.: Progress 1964-1973
S.P. Khromov, M.A. Petrosyants. Small-scale eddies. Meteorology and climatology. Archived from the original on August 23, 2011. Retrieved June 8, 2009.
(unavailable link)
Mezentsev V. A., “Unsolved Earth: stories about how our planet was discovered and continues to be discovered” / reviewer - Dr. geogr. Sciences E. M. Murzaev, - M.: Mysl, 1983, P. 136-142
G. Lyuboslavsky: // Encyclopedic Dictionary of Brockhaus and Efron: In 86 volumes (82 volumes and 4 additional ones). - St. Petersburg. , 1890-1907.
Chernysh I. V., "Traveler's Hiking Encyclopedia", - M.: FAIR-PRESS, 2006, P. 289, ISBN 5-8183-0982-7
John Wiseman « Complete Guide on survival", - M.: AST, 2011, P. 549, ISBN 978-5-17-045760-1
Konstantin Ranks“Desert Russia”, - M.: Eksmo, 2011, pp. 185-187, ISBN 978-5-699-46249-0
Kravchuk P. A. Records of nature. - L.: Erudite, 1993. - 216 p. - 60,000 copies. - ISBN 5-7707-2044-1
(English) National Severe Storms Laboratory VORTEX: Unraveling the Secrets. National Oceanic and Atmospheric Administration (October 30, 2006). Archived from the original on November 4, 2012.
(English) Michael H Mogil Extreme Weather. - New York: Black Dog & Leventhal Publisher, 2007. - P. 210–211. - ISBN 978-1-57912-743-5
(English) Kevin McGrath Mesocyclone Climatology Project. University of Oklahoma (November 5, 1998). Archived from the original on November 4, 2012. Retrieved November 19, 2009.
(English) Seymour, Simon (2001). Tornadoes. New York City, New York: HarperCollins. p. 32. ISBN 978-0-06-443791-2.

Links

Tornado in Krasnogorsk on August 3, 2007 - meteorological data and video on the website Meteoweb.ru, 07/19/2008.

A tornado (synonyms - tornado, thrombus, meso-hurricane) is a strong whirlwind that forms in hot weather under a well-developed cumulonimbus cloud and spreads to the surface of the earth or reservoir in the form of a giant dark rotating column or funnel.

The vortex has a vertical (or slightly inclined to the horizon) axis of rotation, the height of the vortex is hundreds of meters (in some cases 1-2 km), the diameter is 10-30 m, the lifetime is from several minutes to an hour or more.

The tornado passes through a narrow strip, so there may not be a significant increase in wind directly at the weather station, but in fact inside the tornado the wind speed reaches 20-30 m/s or more. A tornado is most often accompanied by heavy rain and thunderstorms, sometimes hail.

In the center of the tornado there is very low pressure, as a result of which it sucks into itself everything that it encounters on the way, and can lift water, soil, individual objects, buildings, sometimes carrying them over considerable distances.

Possibilities and methods of forecasting

A tornado is a phenomenon that is difficult to predict. The tornado monitoring system is based on a system of visual observations by a network of stations and posts, which practically allows only the azimuth of the tornado’s movement to be determined.

By technical means Weather radars are sometimes used to detect tornadoes. However, conventional radar is not able to detect the presence of a tornado because the size of the tornado is too small. Cases of detection of tornadoes by conventional radars were observed only at a very close distance. Radar can be of great help when tracking a tornado.

When the radio echo of a cloud associated with a tornado can be identified on the radar screen, it becomes possible to warn about the approach of a tornado one to two hours in advance.

Doppler radars are used in the operational work of a number of meteorological services.

Protection of the population during hurricanes, storms, tornadoes

In terms of the speed of spread of danger, hurricanes, storms and tornadoes can be classified as emergency events with a moderate speed of spread, which allows wide complex preventive measures both in the period preceding the immediate threat of occurrence, and after their occurrence - until the moment of direct impact.

These time-based measures are divided into two groups: advance (preventive) measures and work; operational protective measures carried out after the announcement of an unfavorable forecast, immediately before a given hurricane (storm, tornado).

Advance (preventive) measures and work are carried out in order to prevent significant damage long before the onset of the impact of a hurricane, storm and tornado and can cover a long period of time.

Advance measures include: restrictions on land use in areas prone to hurricanes, storms and tornadoes; restrictions on the location of hazardous production facilities; dismantling of some outdated or fragile buildings and structures; strengthening industrial, residential and other buildings and structures; carrying out engineering and technical measures to reduce the risk of hazardous industries in strong wind conditions, incl. increasing the physical resistance of storage facilities and equipment containing flammable and other hazardous substances; creation of material and technical reserves; training of the population and rescue personnel.

Protective measures carried out after receiving a storm warning include: forecasting the path and time of approach to various areas of a hurricane (storm, tornado), as well as its consequences; promptly increasing the size of the material and technical reserve necessary to eliminate the consequences of a hurricane (storm, tornado); partial evacuation of the population; preparation of shelters, basements and other buried premises to protect the population; moving unique and especially valuable property into durable or recessed premises; preparation for restoration work and life support measures for the population.

Tornadoes are not frequent in Russia. The most famous are the Moscow tornadoes of 1904. Then on June 29, several craters descended from a thundercloud over the outskirts of Moscow, destroying a large number of buildings - both urban and rural. Tornadoes were accompanied by thunderstorm phenomena - darkness, thunder and lightning.

The material was prepared based on information from open sources

To know what weightlessness is, you don’t have to be an astronaut and be in space. It’s enough just to go to the barn - as John Garison once did, deciding to sharpen the blade of a plane there. He did not pay attention to the approaching bad weather, since hurricanes are a fairly common occurrence in his area.

As he got to work, carefreely whistling a tune, the lights suddenly went out, a loud roar was heard, and the building began to move. The man opened his eyes already in the air, in complete darkness and silence, and when he wanted to breathe, he could not, and lost consciousness again.

I came to my senses some time later, near open door buildings on a completely unfamiliar mountain. The man himself was covered in a thick layer of dust, and his mind could not comprehend what had happened. And much later, he learned that the consequences of the disaster that swept through his hometown were terrible: it destroyed six hundred houses and maimed/deprived the lives of hundreds of people.

And Garison was lucky for one simple reason: the air masses of the spinning vortex accelerated to supersonic speed, which is why the weight of objects that were on the periphery of the rushing vortex decreased (unlike things that found themselves in the center) - and the vortex, picking up the building, moved it for several tens of kilometers along with all the contents, without causing damage special harm. While other structures, including those made of metal, found themselves in the center of the tornado, were destroyed and pressed into the ground with incredible force.

A tornado is an incredibly scary, mysterious and amazing natural phenomenon that destroys almost everything that comes in its path, sparing neither people nor their property (some of them have such strength that they can easily lift a truck with a trailer into the air and even a house). At the same time, in terms of the force of their action, they are somewhat reminiscent of hurricanes, but the consequences of a tornado for people are usually much more serious and sad.

This phenomenon is always associated with thunderstorms and strong winds and, if observed from the outside, looks incredibly amazing. At this time, a huge, black, terrible cloud approaches across the sky, foreshadowing the approach of a hurricane, and the thunder emanating from it thunders more and more, lightning flashes more and more often. Some time later, a huge spinning vortex appears on one side of the cloud (although it is worth noting that there is often a two-sided tornado when it descends from both sides of the cloud). In the Northern Hemisphere it moves mainly clockwise, and the speed air masses inside the “trunk” it ranges from 18 m/s to 1300 km/h.

Wriggling like a snake, he approaches the edge of the terrible cloud and begins to descend at great speed. At the same time, a huge spinning column of dust rises towards him from the ground, collides with the rotating air - and forms a shape reminiscent of the trunk of a huge elephant. The height of such a figure ranges from 800 m to 1.5 km, and its diameter is sea water ranges from 25 to 100 meters and on land - from 100 meters to a whole kilometer, and in exceptional cases can even reach two.

The air inside such a “trunk”, rising in a spiral upward, rotates at breakneck speed - from 70 to 130 km/h. Tornadoes are terrifyingly powerful when air masses rush at a speed of 320 km/h. This vortex does not stand still, it is in constant motion and moves along with the cloud that generated it, while its speed usually ranges from 20 to 60 km/h.

You can judge the speed of rotation of the air inside such a vortex by the flying branches, logs and other objects captured by it (it often happens that a few tens of meters from the tornado the air does not move at all and complete calm reigns). The “trunk” rushes at great speed, so after one or two minutes it completely leaves the territory it destroyed, after which a thunderstorm begins with heavy rain.

Educational phenomenon

Despite the fact that scientists have already studied this amazing natural phenomenon quite well, the mystery of the origin of air vortices of such strength has not been fully solved. There is no doubt that a tornado is just one of the types of movements of such transparent and, at first glance, weightless air.

Tornadoes are supposedly born in the middle of a huge thundercloud at an altitude of 3 to 4 km from the surface of the earth - this is where the so-called axis of air flows is located and you can observe strong ascending air currents and wind surges that are sharp not only in direction, but also in strength.

Warm moist air, finding itself in a cloud, collides with cold air masses that were formed over cold areas of the earth's (sea) surface . When water vapor collides, it condenses, causing raindrops to appear and heat to be released. Warm air masses go upward and create a rarefaction zone there, which draws in not only the nearby warm steam-saturated air of the cloud, but also the cold air located underneath it (at the same time, the temperature of the cold air, after it finds itself in the rarefaction zone, cools even more).

As a result, it stands out great amount energy and a funnel is formed, which descends to the earth's surface, continuing to draw into the rarefied zone absolutely everything that the air masses are capable of lifting. If a tornado is completely hidden between a layer of dust or a wall of rain, it becomes extremely dangerous, primarily because meteorologists are not always able to notice this phenomenon in time and warn about the danger.

Once on the ground, the vacuum zone does not stand still and constantly moves to the side, capturing more and more new portions of cold air. The “trunk,” bending, moves in contact with the surface of the earth, and if there is precipitation, it is insignificant.

When the volumes of cold or warm moist air necessary for a tornado run out, the tornado begins to weaken, the “trunk” narrows and, breaking away from the earth’s surface, returns home to the cloud.

An air vortex can last quite a long time. For example, the Mattoon tornado lasted the longest: 7 hours 20 minutes. he covered 500 km, killing 110 people.

Kinds

Scientists identify several types of tornadoes:

Scourge-like - this type of tornado is considered the most common. The funnel in it is smooth, thin, sometimes tortuous, and its length often significantly exceeds the radius. Such tornadoes are not too strong and destructive; they often float down into the water.
Vague - look like shaggy, spinning clouds that reach the earth's surface. However, sometimes they can be so wide that their diameter is significantly greater than their height (therefore, all craters wider than 0.5 km are usually called vague). These tornadoes are usually very strong because, due to the fact that they cover a large area and the wind travels at terrifying speeds, they are capable of causing considerable damage.
Composite - are several pillars at once, curling around the main tornado. Tornadoes are extremely powerful and can cause damage over a wide area.

Fiery - such whirlwinds are generated by a cloud that arises either due to a strong fire or due to a volcanic eruption. They are extremely dangerous due to the fact that they are capable of spreading fire and causing a fire over several tens of kilometers.
Aquatic - appear mainly over the oceanic, sea surface, and sometimes over lakes. Formed mainly over areas with cold water and high temperature air. The lower part of the funnel, approaching the water, spins and mixes upper layer water, creating a cloud of water dust from it and forming a waterspout. Such a tornado does not last long, only a few minutes.
Earthy - extremely rare view tornadoes are formed only during serious natural disasters. They usually have a whip-like shape, the thick part of the “trunk” is located near the ground. In the middle of the vortex, a thin column of earth spins, behind it (if it arose due to a landslide) is a shell of earthen slurry. If the appearance of such a tornado is caused by an earthquake, it often lifts huge stones from the ground, which can be extremely dangerous for people.
Snow - a tornado of this type is formed in winter, during a strong snowstorm.
Sand tornadoes - similar tornadoes differ from real tornadoes, since they are formed not in the sky, in a cloud, but under the influence of sunlight, which heats the sand to such an extent that the pressure in this place decreases - and, accordingly, air masses rush here from all sides. After this, the sand and wind, thanks to the rotation of the planet, begin to swirl, forming a funnel of impressive size, creating a sand column reminiscent of a tornado, which is capable of moving and can last for about two hours.

The emergence of hurricanes

Hurricanes are somewhat similar in nature to a tornado, the wind speed of which can reach 120 km/h. Unlike tornadoes, hurricanes have a horizontal direction, come mainly from the sea and are formed over the sea surface, cold air accumulates in water, low pressure appears and, naturally, high humidity is observed. At the same time, above the earth's surface, everything is the other way around - pressure is high, humidity is low, so warm air masses from land go to the sea, where there is low pressure and collide with cold air. The greater the temperature difference between atmospheric fronts, the stronger the wind blows: from gusty to squally, then to a hurricane.

Hurricanes are capable of moving quite a long distance from the coast, causing downpours and rain. If the speed of air mass movement is too high, hurricanes may well cause flooding in coastal regions, destroy houses, demolish light buildings, lift people and other objects into the air and forcefully throw them to the ground.

Where do they meet

IN Lately Tornadoes are increasingly appearing in places where they have never been before and where they have never reached. There are areas where waterspouts and tornadoes are commonplace, frequent occurrences and little surprise to local residents.

Tornadoes mainly form in temperate latitudes, both northern and southern hemispheres, between 60 and 45 parallels in Europe, in the USA (it is here that scientists have recorded the largest number of rotating vortices) covers a much larger area - up to the 30th parallel. In spring and summer, the occurrence of tornadoes is observed five times more often and mainly in the daytime.

Precautionary measures

If you find yourself in the area of a tornado, in order to survive, you must follow simple rules. If possible, you need to hide in the strongest building, preferably one made of reinforced concrete and with a steel frame. You can escape from the elements in a cave or some kind of underground shelter; if there is a basement, you need to go down, if not, hide in a bathroom or other small room, away from window and doorways.

To prevent the house from falling apart due to changes in atmospheric pressure, all windows and doors need to be closed from the approaching elements, and on the other hand, on the contrary, open and secure them. You also need to turn off the gas and turn off the electricity.

Hiding from the elements in a car is extremely dangerous, since a tornado can lift it into the air and throw it down from a great height. If it so happens that a spinning vortex finds you in an open space, you need to get away from it as quickly as possible, moving perpendicular to the movement of the “trunk”. If it is not possible to escape from the elements, you need to find some kind of depression (ravine, hole, trench, ditch) and press tightly to the earth’s surface - this will reduce the likelihood of injury from heavy objects.