Tornadoes and hurricanes. The territory of any region is exposed to hazardous natural phenomena, the development and negative manifestation of which in the form of disasters. Presentation for geography lessons on the topic: "Tornado" presentation for a geography lesson (7th grade) on the topic T

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Disaster
A natural disaster is a catastrophic natural phenomenon (or process) that can cause numerous casualties, significant material damage and other severe consequences. Natural disasters include earthquakes, volcanic eruptions, mudflows, landslides, landslides, floods, droughts, cyclones, hurricanes, tornadoes, snow drifts and avalanches, prolonged heavy rains, severe persistent frosts, extensive forest and peat fires. Natural disasters also include epidemics, epizootics, epiphytoties, and the massive spread of forest and agricultural pests.

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Tornado
TORONDA, an atmospheric vortex that arises in a thundercloud and then spreads in the form of a dark arm or trunk towards the surface of land or sea; in the upper part it has a funnel-shaped expansion, merging with the clouds. When a tornado descends to the earth's surface, its lower part also becomes expanded, similar to an overturned funnel. The height of a tornado can reach 800-1500 m. The air in it usually rotates counterclockwise, and at the same time it rises in a spiral upward, drawing in dust or water; rotation speed - several tens of m/sec.

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A tornado does not live long, since pretty soon the cold and warm air masses mix, and thus the cause that supports it disappears. However, even over a short period of its life, a tornado can cause enormous destruction.

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Let us consider, to a first approximation, the processes occurring in thunderclouds. Abundant moisture entering the cloud from the lower layers generates a lot of heat, and the cloud becomes unstable. It produces rapid upward flows of warm air, which carry masses of moisture to a height of 12-15 km, and equally rapid cold downward flows, which fall down under the weight of the resulting masses of rain and hail, strongly cooled in the upper layers of the troposphere.

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On June 29, 1904, a strong whirlwind swept over the eastern part of Moscow. His path lay not far from three Moscow observatories: the University Observatory in the western part of the city, the Land Survey Institute in the eastern part, and the Agricultural Academy in the northwestern part, so valuable material was recorded by the recorders of these observatories. The length of the tornado's path was about 40 km, the width always varied from 100 to 700 m.

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The tornado caused enormous destruction along its path. The villages of Ryazantsevo, Kapotnya, Chagino were destroyed; then the hurricane hit the Lublin Grove, uprooted and broke up to 7 hectares of forest, then destroyed the villages of Graivoronovo, Karacharovo and Khokhlovka, entered the eastern part of Moscow, destroyed the Annenhof Grove in Lefortovo, planted under Tsarina Anna Ioanovna, and tore off the roofs of houses in Lefortovo , went to Sokolniki, where it felled a century-old forest, headed to Losinoostrovskaya, where it destroyed 120 hectares of large forest, and disintegrated in the Mytishchi region. Further there was no tornado, and only a strong storm was noted.

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In appearance, the vortex was a column, wide at the bottom, gradually narrowing in the form of a cone and expanding again in the clouds; in other places it sometimes took the form of just a black spinning pillar. Many eyewitnesses mistook it for rising black smoke from a fire. In those places where the tornado passed through the Moscow River, it captured so much water that the riverbed was exposed.

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In some places, the swirling movements of air are clearly visible from the nature of the windfall, but in most cases, downed trees, even in small spaces, lay in all possible directions. The picture of the destruction of the Moscow tornado turned out to be very complex. Analysis of its traces led us to believe that on June 29, 1904, several tornadoes rushed through Moscow. One of which moved in the direction of Lyublino - Rogozhskaya Zastava - Lefortovo - Sokolniki - Losinoostrovskaya-Mytishchi, and the second - Besedy - Grayvoronovo - Karacharovo - Izmailovo - Cherkizovo.

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This is what the Moscow Leaflet wrote (1904, No. 170). Near Cherkizovo “...suddenly a black cloud completely fell to the ground and covered the metropolitan garden and grove with an impenetrable veil. All this was accompanied by terrible noise and whistling, thunderclaps and the continuous crash of falling large hail. There was a deafening blow, and a huge linden tree fell onto the terrace. Her fall was extremely strange, since she fell onto the terrace through the window and with the thick end first. The hurricane threw it 100 m through the air. The grove was especially damaged. In three or four minutes it turned into a clearing, completely covered with fragments of huge birch trees, in some places uprooted from the ground and thrown over considerable distances. The brick fence around the grove was destroyed, and some bricks were thrown back several fathoms.”

Tornado Work by 5th grade student Peter Radzishevsky

A tornado, an atmospheric vortex that arises in a thundercloud and then spreads in the form of a dark arm or trunk towards the surface of land or sea; in the upper part it has a funnel-shaped expansion, merging with the clouds. When the Tornado descends to the earth's surface, its lower part also becomes expanded, resembling an overturned funnel. The height of the tornado can reach 800-1500 m. The air in it usually rotates counterclockwise, and at the same time it rises in a spiral upward, drawing in dust or water; rotation speed - several tens of meters per second. Due to the fact that the air pressure decreases inside the vortex, water vapor condenses there; this, together with the retracted part of the cloud, dust and water, makes the Tornado visible. The diameter of a tornado over the sea is measured in tens of m, over land - hundreds of m. A tornado is an atmospheric vortex

Tornado - on water and land The name of tornadoes (also blood clots or tornadoes) is a special kind of vortices observed in the warm season in the lower layers of the atmosphere and characterized by special destructive actions. Clouds are formed in the presence of special dark and low clouds, very similar in appearance to thunderclouds. At the lower edge of such a cloud, trunk-like protrusions, or appendages, usually descending, are usually observed, whirling like a vortex by a strong wind. Before a tornado or blood clot occurs, one of these appendages begins to lengthen and stretch downwards. If such a cloud passes over the sea or other waters, the surface of the water under such an elongating appendage begins to ripple, the sea seems to come to a boil, the water level here rises, and a vortex-like movement is observed in the rising water; the column of water grows upward and finally connects with the protrusion descending from the cloud into one whole. Another name for a tornado that occurs over land is a thrombus. It appears in a thundercloud and spreads downward in the form of a dark cloud arm or a narrow funnel. Its diameter can reach tens or even hundreds of meters; vertically it often reaches the surface of the earth. The tornado does not last long. It moves along with the cloud depending on the direction and strength of the wind. However, a tornado can cause great destruction. Most often, this natural phenomenon occurs over a flat surface, in the steppe or on the plain. If he encounters an area covered with any vegetation on his way, he uproots trees and can even lift them into the air. Anything that is not firmly anchored to the ground is in danger of being knocked over, broken, torn out, or bent

A tornado usually occurs in the warm sector of a cyclone, often before a cold front, and moves in the same direction in which the cyclone moves (movement speed 10-20 m/sec). During its existence, a tornado travels a path 40-60 km long. The formation of a tornado is associated with particularly strong instability in the stratification of the atmosphere. A tornado is accompanied by a thunderstorm, rain, hail and, if it reaches the surface of the earth, it almost always causes great destruction, sucking in water and objects encountered on its path, lifting them high up and carrying them over considerable distances. A tornado at sea poses a great danger to ships. A tornado over land is sometimes called a blood clot; in the United States they are called a tornado. Tornado and consequences

Listen carefully to weather reports in your area, especially in summer. Forecasters will definitely report an approaching storm and/or squally wind, which are harbingers or satellites of a tornado. If you have a private home, constantly monitor the condition of the residential building and outbuildings. Pay special attention to the condition of the roofs of these buildings. Reinforce the cellar with concrete blocks, but in such a way that if the house collapses or moves, you will not be trapped. If you live in an apartment, check the condition of the window frames and door frames, so that if it is impossible to shelter from a tornado in the basement (for example, due to the lack of one in many modern houses), you will be relatively safe in the room. Free loggias and balconies from things and especially explosive objects (for example, gasoline or liquefied gas cylinders). If the radio reports an impending storm and the possibility of a tornado, close all doors and windows and lie down on the floor, under a bed or under a closet if you cannot go down to the cellar or basement. Don't forget to turn off the power and turn off the gas. If a tornado catches you on the street, immediately run to the nearest room and take shelter there. Avoid light buildings, power lines, bridges. Avoid sheltering near parks, rivers and lakes. Use cardboard or plastic boxes, sheets of plywood, etc. to protect against flying glass shards, tree branches and debris. You will be incredibly lucky if at this time you are literally a few steps from the metro. If you notice a tornado while in a car, immediately get out of it and take shelter in a building or basement or, if you are outside the city, in hollows, ditches and narrow ravines. Do not go near bodies of water or trees; cover your head with at least clothing while moving. How to escape from a tornado

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Tornadoes and tornadoes

Plan: Name and definition of tornado and tornado. Characteristics Negative consequences for humans Protective measures (to reduce damage)

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A tornado is a strong atmospheric vortex in the central part of a cyclone; water vapor quickly rising into the atmosphere, when condensed, forms a thundercloud with a large content of ice crystals.

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The energy of a typical tornado is equal to the energy of a reference atomic bomb of 20 kilotons of TNT, similar to the first atomic bomb detonated in the United States.

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The shape of tornadoes can be varied - a column, a cone, a glass, a barrel, a whip-like rope, an hourglass, the horns of the “devil”, etc., but most often tornadoes have the shape of a rotating trunk, a pipe or a funnel hanging from the mother cloud

Rotation in tornadoes occurs counterclockwise, as in cyclones in the northern hemisphere of the Earth.

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When air rotates at a speed of 100 m per second, an air funnel of at least 200 meters is created with the air discharged inside it. Centrifugal forces drive heavy drops of water and hail to the periphery of the funnel, which create its walls 10-20 meters thick. The weight of such a funnel forces it to descend to the ground in the form of a hollow column. Sticking to the ground, this formation, with its compacted rain-hail shell, sweeps away everything in its path. Typhoon is a Chinese word that translates to “wind that beats.” Hurricane is the English word hurricane transliterated into Russian.

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Tornadoes sweeping over land are called tornadoes. A tornado sometimes lifts houses and residents into the air, transporting them some distances. According to statistics, about 400 people die annually from tornadoes. The consequences can be very diverse. Houses and farms may be destroyed, people may die.

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This is what a tornado looks like in the sea...

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The main signs of the occurrence of hurricanes, storms and tornadoes are: increased wind speed and a sharp drop in atmospheric pressure; heavy rains and storm surge; rapid fall of snow and ground dust. If you live in an area exposed to hurricanes, storms and tornadoes (Far Eastern, Central and other economic regions of the Russian Federation), familiarize yourself with the situation and proceed.

The territory of any region is exposed to hazardous natural phenomena, the development and negative manifestation of which in the form of catastrophes and natural disasters annually causes enormous damage and leads to loss of life. The most dangerous are tornadoes and hurricanes. The territory of any region is exposed to hazardous natural phenomena, the development and negative manifestation of which in the form of catastrophes and natural disasters annually causes enormous damage and leads to loss of life. The most dangerous are tornadoes and hurricanes.

From the cloud, cold air descends to the surface of the earth, meeting the warm air rising upward. A rotational movement of air occurs - a tornado. Inside the tornado, the pressure drops greatly. A tornado, having descended to the surface of the earth, spins noisily and, like a giant vacuum cleaner, sucks in dust, sand, water, grass, stones and other objects.

Tornadoes move at the speed with which the wind drives them: km/hour. The average distance a tornado travels is about 25 km, and the average width of a tornado is 150 m.

A tornado is rated from 0 to 5 depending on its intensity and the consequences (destruction) caused. The intensity of a tornado is determined by the speed of the internal wind, which can range from 18 to 140 meters per second. Therefore, the nature of the destruction caused by a tornado can be very different - from weak to catastrophic.

In America and Western Europe, the terms “tornado” and “thrombus” are used. These words are synonyms for the word “tornado”, because denote the same phenomenon - a rotating vortex. By the way, the direction of air rotation in a tornado funnel in the northern hemisphere is counterclockwise, and in the southern hemisphere it is clockwise.

When receiving information about the approach of a hurricane, you should close doors, attics, and windows. Cover the glass with strips of paper. Remove objects from window sills that could cause injury if dropped. Turn off the gas. Prepare lanterns and candles. Create a supply of water and food for 2-3 days. Prepare medications. Keep radios and televisions on at all times: they can convey various messages and orders.