Atmospheric vortices hot air hotbed geography. Characteristics of atmospheric vortices. Fragment of the work for review

Atmosphere("atmos" - steam) - the air shell of the Earth. The atmosphere, according to the nature of temperature change with height, is divided into several spheres

The radiant energy of the Sun is the source of air movement. Between warm and cold masses there is a difference in temperature and atmospheric air pressure. It creates wind.

Various concepts are used to indicate the movement of the wind: tornado, storm, hurricane, storm, typhoon, cyclone, etc.

To systematize them, all over the world use Beaufort scale, which estimates the strength of the wind in points from 0 to 12 (see table).

Atmospheric fronts and atmospheric vortices give rise to formidable natural phenomena, the classification of which is shown in fig. 1.9.

Rice. 1.9. Natural hazards of a meteorological nature.

In table. 1.15 shows the characteristics of atmospheric vortices.

Cyclone(hurricane) - (Greek whirling) - this is a strong atmospheric disturbance, a circular vortex movement of air with a decrease in pressure in the center.

Depending on the place of origin, cyclones are divided into tropical And extratropical. The central part of the cyclone, which has the lowest pressure, light clouds and light winds, is called "eye of the storm"("eye of the hurricane").

The speed of the cyclone itself is 40 km/h (rarely up to 100 km/h). Tropical cyclones (typhoons) move faster. And the speed of wind whirlwinds is up to 170 km/h.

Depending on the speed, there are: - hurricane (115-140 km/h); - strong hurricane (140-170 km/h); - hard hurricane (more than 170 km/h).

Hurricanes are most common in the Far East, in the Kaliningrad and Northwestern regions of the country.

Harbingers of a hurricane (cyclone): - a decrease in pressure in low latitudes and an increase in high latitudes; - the presence of perturbations of any kind; - changeable winds; - sea swell; - wrong ebbs and flows.

Table 1.15

Characteristics of atmospheric vortices

The damaging factors of the hurricane are given in Table. 1.16.

Table 1.16

Damage factors of a hurricane

Tornado(tornado) - an extremely rapidly rotating funnel hanging from a cumulonimbus cloud and observed as a "funnel cloud" or "pipe". The classification of tornadoes is given in Table. 3.1.26.

Table 1.17

Tornado classification

On the territory of Russia, tornadoes are common: in the north - near the Solovetsky Islands, on the White Sea, in the south - on the Black and Azov Seas. - Small, short-acting tornadoes travel less than a kilometer. - Small tornadoes of significant action travel a distance of several kilometers. - Large tornadoes travel a distance of tens of kilometers.

The damaging factors of tornadoes are given in Table. 1.18.

Table 1.18

Damaging factors of tornadoes

Storm- long, very strong wind with a speed of more than 20 m/s, observed during the passage of a cyclone and accompanied by strong waves at sea and destruction on land. Duration of action - from several hours to several days.

In table. 1.19 shows the classification of storms.

Table 1.19

Storm classification

The damaging factors of storms are given in Table. 1.20.

Table 1.20.

The damaging factors of storms

Population actions

Storm- an atmospheric phenomenon, accompanied by lightning and deafening thunder. Up to 1800 thunderstorms occur simultaneously on the globe.

Lightning- a giant electric spark discharge in the atmosphere in the form of a bright flash of light.

Table 1.21

Types of lightning

Table 1.21

Striking factors of lightning

Actions of the population during a thunderstorm.

hail- particles of dense ice falling in the form of precipitation from powerful cumulonimbus clouds.

Fog cloudiness of the air above the Earth's surface caused by the condensation of water vapor

Ice- frozen drops of supercooled rain or fog, deposited on the cold surface of the Earth.

snow drifts- heavy snowfall at wind speed over 15 m/s and snowfall duration over 12 hours.

Characteristics of hurricanes, storms, tornadoes

Hurricanes, storms, tornadoes are wind meteorological phenomena , related to natural disasters capable of causing great material damage and death.

Wind- the movement of air relative to the earth's surface, resulting from the uneven distribution of heat and atmospheric pressure. The main indicators of the wind - direction (from the high pressure zone to the zone low pressure) and speed (measured in meters per second (m/s; km/h; miles/hour).

Many words are used to indicate the movement of the wind: hurricane, storm, storm, tornado ... To systematize them, they use Beaufort scale(developed by the English admiral F. Beaufort in 1806) , which allows you to very accurately estimate the strength of the wind in points (from 0 to 12) according to its effect on ground objects or on waves in the 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.

Beaufort scale (Table 1)

Characteristics of atmospheric vortices

Hurricane

A hurricane is a fast wind movement, with a speed of 32.7 m / s (117 km / h), although it can exceed 200 km / h (12 points on the Beaufort scale) (Table 1), with a significant duration of several days ( 9-12 days), continuously moving over the oceans, seas and continents and possessing great destructive power. 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 little damage is added to this zone. Then the width of the hurricane is measured in hundreds of kilometers, sometimes reaching 1000 km. Hurricanes occur at any time of the year, but most often from July to October. In the remaining 8 months they are rare, their paths are short.

A hurricane is one of the most powerful manifestations of nature, in its consequences it is comparable to an earthquake. Hurricanes are accompanied by fallout a large number rainfall and lower temperatures. The width of the hurricane is from 20 to 200 kilometers. Most often, hurricanes sweep over the USA, Bangladesh, Cuba, Japan, the Antilles, Sakhalin, and the Far East.

In half of the cases, the wind speed during a hurricane exceeds 35 m/s, reaching up to 40-60 m/s, and sometimes up to 100 m/s. Hurricanes are classified into three types based on wind speed:

- Hurricane(32 m/s and more),

- strong hurricane(39.2 m/s or more)

- fierce hurricane (48.6 m/s and more).

Cause of these hurricane winds is the occurrence, as a rule, on the line of collision of the fronts of warm and cold air masses, powerful cyclones with a sharp pressure drop from the periphery to the center and with the creation of a vortex air flow moving in lower layers(3-5 km) in a spiral towards the middle and up, in the northern hemisphere - counterclockwise. Forecasters assign each hurricane a name or a four-digit number.

Cyclones, depending on the place of their occurrence and structure, are divided into:

1) Tropical cyclones found over warm tropical oceans, usually moves westward during formation, and curves poleward after formation. A tropical cyclone that has reached unusual strength called:

-tropical hurricane if it is born in the Atlantic Ocean and adjacent seas. North and South America. Hurricane (Spanish huracán, English hurricane) named after the Mayan wind god Huracan;

- typhoon - if it originated over the Pacific Ocean. Far East, Southeast Asia;

- cyclone - in the Indian Ocean region.

Rice. Structure of a tropical cyclone

The eye is the central part of the cyclone in which the air descends.

The wall of the eye is a ring of dense thunderstorm cumulus clouds surrounding the eye.

The outer part of a tropical cyclone is organized into rainbands - bands of dense thunderstorm cumulus clouds that slowly move towards the center of the cyclone and merge with the wall of the eye.

One of the most common definitions of the size of a cyclone, which is used in various databases, is the distance from the center of circulation to the outermost closed isobar, this distance is called radius of the outer closed isobar.

2) Cyclones temperate latitudes can form both over land and over water. They usually move from west to east. characteristic feature such cyclones is their great "dryness". The amount of precipitation during their passage is much less than in the zone of tropical cyclones.

3) The European continent is affected by both tropical hurricanes that originate in the central Atlantic and cyclones of temperate latitudes.

Rice. Hurricane Isabel 2003, photograph from the ISS - you can clearly see the characteristic eyes of tropical cyclones, the wall of the eye and the surrounding rain bands.

Storm (storm)

A storm (storm) is a type of hurricane that is inferior to it in strength. Hurricanes and storms differ only in wind speed. A storm is a strong, prolonged wind, but its speed is less than that of a hurricane of 62 - 117 km / h, (8 - 11 points on the Beaufort scale). A storm can last from 2-3 hours to several days, covering a distance (width) from tens to several hundred kilometers. A storm that breaks out at sea is called a storm.

Depending on the color of the particles involved in the movement, there are: black, red, yellow-red and white storms.

Depending on the wind speed, storms are classified:

Storms are divided into:

1) Vortex- are complex eddy formations due to cyclonic activity and extending to large areas. They are:

- Snowstorms (winter) formed in winter. Such storms are called snowstorms, snowstorms, snowstorms. Accompanied by severe frost and blizzard, they can move huge masses of snow over long distances, which leads to heavy snowfalls, blizzards, snow drifts. Snow storms paralyze traffic, disrupt power supply, and lead to tragic consequences. The wind contributes to the cooling of the body, frostbite.

- Squall Storms – occur suddenly, and in time are extremely short (several minutes). For example, within 10 minutes the wind speed can increase from 3 to 31 m/s.

2) Stream storms- These are local phenomena of small distribution, weaker than whirlwind storms. Pass most often between the chains of mountains connecting the valleys. Subdivided into:

- stock - the air flow moves down the slope from top to bottom.

- Jet - airflow moves horizontally or uphill.

Rice. Storm (storm.) Work on the masts of a sailing ship in a storm.

Tornado (tornado)

Tornadoes (in English terminology tornado from Spanish. tornar“twirl, twist”) is an atmospheric vortex in the form of a dark sleeve with a vertical curved axis and a funnel-shaped expansion in the upper and lower parts. The air rotates at a speed of 50-300 km / h counterclockwise and rises in a spiral. Inside the stream, the speed can reach 200 km / h. Inside the column, there is reduced pressure (rarefaction), which causes suction, lifting up everything that is encountered on the way (earth, sand, water, sometimes very heavy objects). The height of the sleeve can reach 800 - 1500 meters, the diameter - from several tens above water to hundreds of meters above land. The length of the path of a tornado ranges from several hundred meters to tens of kilometers (40 - 60 km.). The tornado spreads, following the terrain, the speed of the tornado is 50 - 60 km/h.

A tornado arises in a thundercloud (in the upper part it has a funnel-shaped extension that merges with clouds) saturated with charged ions and then spreads in the form of a dark sleeve or trunk towards the land or sea surface. When the tornado descends to the surface of the earth or water, its lower part also becomes expanded, similar to an overturned funnel. Tornadoes occur both above the water surface and over land, much more often than hurricanes, usually in the warm sector of the cyclone, more often before the cold front. Its formation is associated with a particularly strong instability of the regular distribution of atmospheric air temperatures over height (atmospheric stratification). It is often accompanied by thunderstorms, rain, hail, and a sharp increase in wind.

Tornadoes are observed in all regions of the globe. Most often they occur in Australia, Northeast Africa, the most common in America (USA), in the warm sector of the cyclone before the cold front. The tornado moves in the same direction as the cyclone. There are more than 900 of them a year, and most of them originate and cause the most damage in Tornado Valley.

Tornado Valley stretches from West Texas to the Dakotas 100 miles north to south and 60 miles east to west. Warm, moist air from the north of the Gulf of Mexico meets dry, cold winds from the south from Canada. Huge clusters of thunderclouds begin to form. The air rises sharply inside the clouds, cools down there and descends. These streams collide and rotate relative to each other. There is a thunderstorm cyclone in which a tornado is born.

Tornado classification

Bitch-like - this is the most common type of tornadoes. The funnel looks smooth, thin, and can be quite tortuous. The length of the funnel considerably exceeds its radius. Weak whirlwinds and whirlpools that descend on the water are, as a rule, whip-like whirlwinds.

vague- look like shaggy, rotating clouds reaching 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 whirlwinds, often compound ones. They cause enormous damage due to their large size and very high wind speeds.

Composite- a composite tornado in Dallas in 1957. They can consist of two or more separate blood clots around the main central tornado. Such tornadoes can be of almost any power, however, most often they are very powerful tornadoes. They cause significant damage over vast areas. Most often formed on the water. These funnels are somewhat related to each other, but there are exceptions.

fiery- These are ordinary tornadoes generated by a cloud formed as a result of a strong fire or volcanic eruption. It is these tornadoes that were first artificially created by man (the experiments of J. Dessen (Dessens, 1962) in the Sahara, which continued in 1960-1962). "Absorb" into themselves the tongues of flame, which are drawn to the parent cloud, forming fiery tornado. It can spread a fire for tens of kilometers. They are whip-like. Cannot be vague (the fire is not under pressure like whip-like tornadoes).

Water- these are tornadoes that formed above the surface of the oceans, seas, in a rare case lakes. They “absorb” waves and water into themselves, forming, in some cases, whirlpools that stretch towards the parent cloud, forming a water tornado. They are whip-like. Like fire tornadoes, they cannot be vague (the water is not under pressure, as in whip-like tornadoes).

earthen- these tornadoes are very rare, they form during destructive cataclysms or landslides, sometimes earthquakes above 7 points on the Richter scale, very high pressure drops, very rarefied air. A whip-like tornado is located in a "carrot" (thick part) to the ground, inside a dense funnel, a thin trickle of earth inside, a "second shell" of earthen slurry (if a landslide). In the case of earthquakes, it lifts stones, which is very dangerous.

snowy are snow tornadoes during a heavy snowstorm.

Rice. A tornado and a cavitation cord behind a radial-axial turbine and the distribution of velocity and pressure in the cross sections of these vortex formations.

Hazardous classification natural phenomena Dangerous meteorological (agrometeorological) phenomena - natural processes and phenomena arising in the atmosphere, which, due to their intensity (strength), scale of distribution and duration, have or may have a damaging effect on people, farm animals and plants, objects of the economy and environment. These include: - storms, hurricanes, tornadoes (tornadoes), squalls; - heavy precipitation (snowfall, downpour, hail, blizzard, ice); - hard frost; - intense heat, drought, dry wind; - heavy fog; - late frosts Meteorological and agrometeorological hazards

H, km t° С 3000 exosphere thermosphere mesosphere-90 55 stratosphere troposphere-60 Atmospheric structure

Gas Molecular weight, g/mol Content, % volume Density absolute, g/m 3 relative to dry air Nitrogen 28.10678.967 Oxygen 3220.105 Argon 39.9440.379 Carbon dioxide 44.010.529 Neon 20.18318.18* .695 Helium 4.0035.24* .138 Krypton 83.71.14* .868 Hydrogen 2.0160.5* .07 Ozone 48(0…0.07)* .624 Dry air 28,

Psychrometric booths tall towers and masts balloons, balloons, flying laboratories Space monitoring facilities: meteorological and geophysical rockets artificial satellites Earth spaceships and orbital stations indirect methods The following can be used to study the atmosphere:

The mass of the atmosphere is trillion tons. The mass of pollution is 1/10 thousand % Pollutants in the atmosphere: Accumulate over time Distributed unevenly on Earth Toxic in small concentrations

Sources of air pollution: I - Natural: dust, salt, volcanic. II - Artificial (anthropogenic): Industrial enterprises: - chemical industry enterprises - metallurgical enterprises - thermal power plants - cement plants Road transport Agricultural enterprises - livestock complexes - poultry farms - chemical plant protection products - tillage

The reduction of air pollution is facilitated by: – regulation in major cities traffic flows; – transition of transport to alternative fuel sources (alcohol, gas, etc.) – construction of treatment facilities; – conversion of CHPPs to environmentally friendly fuels; – improvement of production technologies; – centralization of small boiler houses; - the withdrawal of industrial enterprises from the city, etc.

The general circulation of the atmosphere is a system of air currents on a large, planetary scale, carrying huge masses of air from one latitude to another. Rice. Distribution of atmospheric pressure and winds near the earth's surface; on the right - meridional section of the wind direction (according to A.P. Shubaev): 1 - wind direction; 2 - the direction of the horizontal baric gradient

Type of air mass Designation Where it is formed Arctic (Antarctic) A VArctic, Antarctica Temperate latitudes (polar) P W Temperate latitudes Tropical T SU Subtropical and tropical latitudes Equatorial E W Equatorial belt of the earth Main geographical types of air masses

Atmospheric eddiesLocal nameCharacteristic Cyclone (tropical and extratropical) - a closed baric system - eddies with low pressure in the center Typhoon (China, Japan) Willy Willy (Australia) Hurricane (Northern and South America) Width km Height 1-12 km Calm area diameter ("eye of the storm") km Wind speed up to 120 m/s Time of day Characteristics of atmospheric eddies Atmospheric eddies

PrimarySecondary - a strong wind carrying large masses water, mud, sand (up to 250 km/h); - sea waves (higher than 10 m); - showers (mm). - heavy objects carried by the wind; - flooding, flooding of the territory; - destruction of buildings and structures; - breakage of power lines; - howled trees, masts, pipes, supports, etc.; - fires, explosions. The damaging factors of a hurricane Primary Secondary - air currents carrying water, dirt, objects, etc. (wind speed in the funnel up to km / h, sometimes up to 400 km / h); - reduced air pressure in the funnel; - spiral or vertical movement of air flows within the funnel; - showers; - thunderstorms. - destruction of objects during side impacts; - detachment of objects and people, lifting up with transfer to hundreds of meters; - absorption of gaseous and liquid masses with their subsequent release; - breakage of power lines; - fires, explosions; - Flooding of the territory. Damaging factors of tornadoes A tornado is an atmospheric vortex that occurs in a cumulonimbus (thunderstorm) cloud and spreads down, often to the very surface of the earth (water), in the form of a cloud sleeve or trunk Tornado (USA, Mexico) Thrombus (West Europe) Height - from a few hundred meters to several km. Diameter - from several hundred meters to 1.5 km or more. The speed of movement is from up to 100 km/h The speed of rotation of vortices in the funnel is up to 300 km/h Hurricane is a wind of great destructive power and a long duration, which occurs mainly from July to October in the zones of convergence of a cyclone and an anticyclone. Typhoon (Pacific Ocean) Wind speed more than 33 m/s Duration 9-12 days Width - up to 1000 km

Atmospheric whirlwindsLocal nameCharacteristic Flurry - short-term whirlwinds that occur in front of cold atmospheric fronts, often accompanied by a shower or hail and occur in all seasons of the year and at any time of the day. Storm Wind speed 25 m/s or more Duration up to 1 hour Storm is a very strong wind, the speed of which is less than a hurricane. Storm Duration - from several hours to several days Wind speed m / s Width - up to several hundred kilometers Bora - very strong gusty cold wind coastal areas, leading to winter time to icing of port facilities and ships Sarma (on Baikal) Baku Nord Duration - several days Wind speed up to m/s Foehn - a hot dry wind blowing from the slopes of the mountains into the valley. (Caucasus, Altai, Central Asia) Velocity m/s, high temperature and low relative air humidity Characteristics of atmospheric vortices (continued)

Storm - a long, very strong wind with a speed of more than 20 m / s, observed during the passage of a cyclone and accompanied by strong waves at sea and destruction on land. Duration of action - from several hours to several days. Type of storm Primary factors Secondary factors Storm - high wind speed; - great excitement seas - destruction of buildings, watercraft; - destruction, erosion of the coast Dust storm - high wind speed; - high air temperature at extremely low relative humidity; - loss of visibility, dust. - destruction of buildings; - desiccation of soils, death of agricultural plants; - removal of the fertile soil layer (deflation, erosion); - loss of orientation. Snow storm (blizzard, blizzard, snowstorm) - high wind speed; - low temperature; - loss of visibility, snow. - destruction of objects; - hypothermia; - frostbite; - loss of orientation. Flurry - high wind speed (within 10 minutes, the wind speed increases from 3 to 31 m / s) - destruction of buildings; - windbreak. The damaging factors of the storm

Name of the wind regime Wind speed (km/h) PointsSigns Calm 0 - 1.60 Smoke goes straight Light breeze 3.2 - 4.81 Smoke bends Light breeze 6.4 - 11.32 Leaves stir Light breeze 12.9 - 19 33 Leaves moving Moderate breeze 20.9 - 28.94 Leaves and dust flying Fresh breeze 30.6 - 38.65 Thin trees sway Strong breeze 40.2 - 49.96 Thick trees sway Strong wind 51.5 - 61.17 Trunks Trees are bent Storm 62.8 – 74.08 Branches are broken Strong storm 75.5 – 86.99 Roof tiles and pipes are torn off Full storm 88.5 – 101.410 Trees are uprooted Storm 103.0 – 120.711 Damage everywhere Hurricane More than 120.712 Major damage WIND Beaufort scale

Some time ago, before the advent of meteorological satellites, scientists could not even think that about one hundred and fifty cyclones and sixty anticyclones are formed in the Earth's atmosphere every year. Previously, many cyclones were unknown, because they arose in places where there were no meteorological stations that could record their appearance.

In the troposphere, the lowest layer of the Earth's atmosphere, vortices constantly appear, develop and disappear. Some of them are so small and imperceptible that they pass by our attention, others are so large-scale and influence the Earth's climate so strongly that they cannot be ignored (this primarily applies to cyclones and anticyclones).

Cyclones are areas of low pressure in the Earth's atmosphere, in the center of which the pressure is much lower than at the periphery. An anticyclone, on the contrary, is an area of ​​high pressure, which reaches its highest values ​​in the center. Being over the northern hemisphere, cyclones move counterclockwise and, obeying the Coriolis force, try to go to the right. Whereas the anticyclone moves clockwise in the atmosphere and deviates into left side(in the southern hemisphere of the Earth, everything happens the other way around).

Despite the fact that cyclones and anticyclones are absolutely opposite vortices in their essence, they are strongly interconnected with each other: when pressure decreases in one region of the Earth, its increase is necessarily fixed in another. Also for cyclones and anticyclones, there is a common mechanism that makes air flows move: non-uniform heating of different parts of the surface and the rotation of our planet around its axis.

Cyclones are characterized by cloudy, rainy weather with strong gusts of wind arising from the difference in atmospheric pressure between the center of the cyclone and its edges. An anticyclone, on the contrary, in summer is characterized by hot, calm, cloudy weather with very few precipitations, while in winter it sets clear, but very cold weather.

snake ring

Cyclones (Gr. “serpent ring”) are huge eddies, the diameter of which can often reach several thousand kilometers. They are formed in temperate and polar latitudes, when warm air masses from the equator collide with moving towards dry, cold streams from the Arctic (Antarctica) and form a boundary between them, which is called an atmospheric front.

Cold air, trying to overcome the warm air flow remaining below, in some area pushes a part of its layer back - and it comes into collision with the masses following it. As a result of the collision, the pressure between them increases and part of the warm air that turned back, yielding to the pressure, deviates to the side, starting an ellipsoidal rotation.

This vortex begins to capture the layers of air adjacent to it, draws them into rotation and begins to move at a speed of 30 to 50 km / h, while the center of the cyclone moves at a lower speed than its periphery. As a result, after some time, the diameter of the cyclone is from 1 to 3 thousand km, and the height is from 2 to 20 km.

Where it moves, the weather changes dramatically, since the center of the cyclone has low pressure, there is a lack of air inside it, and cold air masses begin to flow in to make up for it. They push warm air up where it cools, and the water droplets in it condense and form clouds from which precipitation falls.

The lifespan of a vortex is usually from a few days to weeks, but in some regions it can last for about a year: usually these are areas of low pressure (for example, the Icelandic or Aleutian cyclones).

It is worth noting that for equatorial zone such vortices are not characteristic, since the deflecting force of the planet's rotation, which is necessary for the vortex-like movement of air masses, does not act here.

The southernmost, tropical cyclone, forms no closer than five degrees to the equator and is characterized by a smaller diameter, but more high speed wind, which often turns into a hurricane. By their origin, there are such types of cyclones as a temperate vortex and a tropical cyclone that generates deadly hurricanes.

Tropical eddies

In the 1970s, tropical cyclone Bhola hit Bangladesh. Although the wind speed and strength were low and only the third (out of five) category of a hurricane was assigned to it, due to the huge amount of precipitation that hit the earth, the Ganges River overflowed its banks and flooded almost all the islands, washing away all the settlements from the face of the earth.

The consequences were catastrophic: during the rampage of the elements, from three hundred to five hundred thousand people died.

A tropical cyclone is much more dangerous than a vortex from temperate latitudes: it forms where the temperature of the ocean surface is not lower than 26 °, and the difference between the air temperature indicators exceeds two degrees, as a result of which evaporation increases, air humidity increases, which contributes to the vertical rise of air masses.

Thus, a very strong thrust appears, capturing new volumes of air that have warmed up and gained moisture over the ocean surface. The rotation of our planet around its axis gives the rise of air the whirling motion of a cyclone, which begins to rotate at great speed, often transforming into hurricanes of terrifying force.

A tropical cyclone is formed only above the ocean surface between 5-20 degrees north and south latitudes, and once on land, it fades rather quickly. Its dimensions are usually small: the diameter rarely exceeds 250 km, but the pressure at the center of the cyclone is extremely low (the lower, the faster the wind moves, so the movement of cyclones is usually from 10 to 30 m/s, and wind gusts exceed 100 m/s) . Naturally, not every tropical cyclone brings death with it.

There are four types of this vortex:

• Disturbance - moves at a speed not exceeding 17m / s;
• Depression - the movement of the cyclone is from 17 to 20 m/s;
• Storm - the center of the cyclone moves at a speed of up to 38m/s;
• Hurricane - a tropical cyclone moves at a speed exceeding 39 m/s.

The center of this type of cyclone is characterized by such a phenomenon as the "eye of the storm" - an area of ​​calm weather. Its diameter is usually about 30 km, but if a tropical cyclone is destructive, it can reach up to seventy. Inside the eye of the storm, the air masses have more warm temperature and lower humidity than in the rest of the vortex.

Calm often reigns here, precipitation abruptly stops at the border, the sky clears up, the wind weakens, deceiving people who, having decided that the danger has passed, relax and forget about precautions. Since a tropical cyclone always moves from the ocean, it drives huge waves in front of it, which, having hit the coast, sweep everything out of the way.

Scientists are increasingly recording the fact that every year a tropical cyclone becomes more dangerous and its activity is constantly increasing (this is due to global warming). Therefore, these cyclones occur not only in tropical latitudes, but also reach Europe at an atypical time of the year: they usually form in late summer/early autumn and never occur in spring.

So, in December 1999, France, Switzerland, Germany, and the UK were attacked by Hurricane Lothar, so powerful that meteorologists could not even predict its appearance due to the fact that the sensors either went off scale or did not work. "Lothar" was the cause of the death of more than seventy people (mostly they became victims of road accidents and falling trees), and only in Germany alone, about 40 thousand hectares of forest were destroyed in a few minutes.

Anticyclones

An anticyclone is a vortex with high pressure at the center and low pressure at the periphery. It is formed in the lower layers of the Earth's atmosphere when cold air masses invade warmer ones. An anticyclone arises in subtropical and subpolar latitudes, and its speed of movement is about 30 km/h.

An anticyclone is the opposite of a cyclone: ​​the air in it does not rise, but descends. It is characterized by the absence of moisture. The anticyclone is characterized by dry, clear, and calm weather, in summer - hot, frosty - in winter. Significant temperature fluctuations during the day are also characteristic (the difference is especially strong on the continents: for example, in Siberia it is about 25 degrees). This is explained by the lack of precipitation, which usually makes the temperature difference less noticeable.

Names of vortices

In the middle of the last century, anticyclones and cyclones began to be given names: this turned out to be much more convenient when exchanging information about hurricanes and cyclone movements in the atmosphere, as it made it possible to avoid confusion and reduce the number of errors. Behind each name of a cyclone and an anticyclone were hidden data about the vortex, down to its coordinates in the lower atmosphere.

Before making a final decision on the name of this or that cyclone and anticyclone, a sufficient number of proposals were considered: they were proposed to be denoted by numbers, alphabet letters, names of birds, animals, etc. This turned out to be so convenient and effective that after some time, all cyclones and anticyclones received names (in the beginning they were female, and in the late seventies, tropical eddies began to be called male names as well).

Since 2002, a service has appeared that offers anyone who wants to name a cyclone or anticyclone by their name. Pleasure is not cheap: the standard price for a cyclone to get the customer's name is 199 euros, and an anticyclone is 299 euros, since the anticyclone occurs less often.

Introduction

1. Formation of atmospheric vortices

1.1 Atmospheric fronts. Cyclone and anticyclone

2. Studying atmospheric vortices at school

2.1 The study of atmospheric vortices in geography lessons

2.2 Study of the atmosphere and atmospheric phenomena from 6th grade

Conclusion.

Bibliography.

Introduction

Atmospheric vortices - tropical cyclones, tornadoes, storms, squalls and hurricanes.

Tropical cyclones- these are vortices with low pressure in the center; they come in summer and winter. T Tropical cyclones occur only at low latitudes near the equator. In terms of destruction, cyclones can be compared with earthquakes or a volcano ami .

The speed of cyclones exceeds 120 m / s, while powerful clouds appear, there are showers, thunderstorms and hail. A hurricane can destroy entire villages. The amount of rainfall seems incredible compared to the intensity of rainfall during the strongest cyclones in temperate latitudes.

Tornado destructive atmospheric phenomenon. This is a huge vertical whirlwind several tens of meters high.

People cannot yet actively fight tropical cyclones, but it is important to prepare in time, whether on land or at sea. For this, meteorological satellites are on duty around the clock, which are of great help in forecasting the paths of tropical cyclones. They photograph whirlwinds, and from the photograph one can quite accurately determine the position of the center of the cyclone and trace its movement. Therefore, in recent times it was possible to warn the population about the approach of typhoons that could not be detected by ordinary meteorological observations.

Despite the fact that the tornado has a destructive effect, at the same time it is a spectacular atmospheric phenomenon. It is concentrated on a small area and all, as it were, before our eyes. On the shore you can see how a funnel extends from the center of a powerful cloud, and another funnel rises towards it from the surface of the sea. After closing, a huge, moving column is formed, which rotates counterclockwise. Tornadoes

are formed when the air in the lower layers is very warm, and in the upper layers it is cold. A very intensive air exchange begins, which

accompanied by a vortex with a high speed - several tens of meters per second. The diameter of a tornado can reach several hundred meters, and the speed is 150-200 km/h. Low pressure is formed inside, so the tornado draws in everything that it meets on the way. Known, for example, "fish"

rains, when a tornado from a pond or lake, along with the water, drew in the fish located there.

StormThis is a strong wind, with the help of which great excitement can begin at sea. A storm can be observed during the passage of a cyclone, a tornado.

The wind speed of the storm exceeds 20 m/s and can reach 100 m/s, and when the wind speed is more than 30 m/s, Hurricane, and wind amplification up to speeds of 20-30 m/s are called flurries.

If in geography lessons only the phenomena of atmospheric vortices are studied, then during the lessons of life safety they learn how to protect themselves from these phenomena, and this is very important, because knowing the methods of protection today's students will be able to protect not only themselves but also friends and relatives from atmospheric vortices.

1. Formation of atmospheric vortices.

The struggle of warm and cold currents, seeking to equalize the temperature difference between north and south, occurs with varying degrees of success. Then the warm masses take over and penetrate in the form of a warm tongue far to the north, sometimes to Greenland, Novaya Zemlya and even to Franz Josef Land; then the masses of Arctic air in the form of a giant "drop" break through to the south and, sweeping away warm air on their way, fall on the Crimea and the republics Central Asia. This struggle is especially pronounced in winter, when the temperature difference between north and south increases. On synoptic maps of the northern hemisphere, one can always see several tongues of warm and cold air penetrating to different depths to the north and south.

The arena in which the struggle of air currents unfolds falls precisely on the most populated parts of the globe - temperate latitudes. These latitudes experience the vagaries of the weather.

The most turbulent regions in our atmosphere are the boundaries of air masses. Huge whirlwinds often arise on them, which bring us continuous changes in the weather. Let's get to know them in more detail.

1.1Atmospheric fronts. Cyclone and anticyclone

What is the reason for the constant movement of air masses? How are pressure belts distributed in Eurasia? What air masses in winter are closer in their properties: sea and continental air of temperate latitudes (mWSH and CLW) or continental air of temperate latitudes (CLWL) and continental Arctic air (CAW)? Why?

Huge masses of air move over the Earth and carry water vapor with them. Some move from land, others from the sea. Some - from warm areas to cold, others - from cold to warm. Some carry a lot of water, others - a little. Often the streams meet and collide.

In the strip separating air masses of different properties, peculiar transition zones arise - atmospheric fronts. The width of these zones usually reaches several tens of kilometers. Here, at the contact of various air masses, during their interaction, a rather rapid change in temperature, humidity, pressure and other characteristics of air masses occurs. The passage of the front through any area is accompanied by cloudiness, precipitation, changes in air masses and related types of weather. In those cases when air masses with similar properties come into contact (in winter, AB and KVUSh - over Eastern Siberia), an atmospheric front does not arise and there is no significant change in the weather.

Over the territory of Russia, the Arctic and polar atmospheric fronts are often located. The arctic front separates the arctic air from the air of temperate latitudes. In the zone of separation of air masses of temperate latitudes and tropical air, a polar front is formed.

The position of atmospheric fronts varies with the seasons of the year.

according to drawing(Fig. 1 ) you can determine wherearctic and polar fronts are located in summer.

(Fig. 1)

Along the atmospheric front, warm air meets colder air. Depending on what air enters the territory, displacing the one that was on it, the fronts are divided into warm and cold.

warm frontIt is formed when warm air moves towards cold air, pushing it back.

At the same time, warm air, being lighter, rises above the cold one smoothly, as if it were a ladder (Fig. 2).

(Fig. 2)

As it rises, it gradually cools, the water vapor contained in it gathers into drops (condenses), the sky is covered with clouds, and precipitation falls. A warm front brings warming weather and prolonged drizzle.

cold front formed during the movement of cold air spirit towards warm. Cold air is heavy, so it squeezes under warm air in a flurry, sharply, with one stroke, lifts it and pushes it up (see Fig. 3).

(Fig. 3)

Warm air is rapidly cooled. Thunderclouds gather above the ground. Heavy rain falls, often accompanied by thunderstorms. Strong winds and squalls often occur. When a cold front passes, it quickly clears and cools down.. Figure 3 shows the sequence in which the types of clouds replace each other during the passage of warm and cold fronts.The development of cyclones is associated with atmospheric fronts, which bring the bulk of precipitation, cloudy and rainy weather to the territory of Russia.

Cyclones and anticyclones.

Cyclones and anticyclones are large atmospheric eddies that carry air masses. On maps, they are distinguished by closed concentric isobars (lines of equal pressure).

Cyclones are vortices with low pressure in the center. Towards the outskirts, the pressure increases, so in the cyclone the air moves towards the center, slightly deviating counterclockwise. In the central part, the air rises and spreads to the outskirts .

As the air rises, it cools, moisture condenses, clouds form, and precipitation falls. Cyclones reach a diameter of 2-3 thousand km and usually move at a speed of 30-40 km/h.East. At the same time, air from more southern regions, i.e., usually warmer, is drawn into the eastern and southern parts of the cyclone, and colder air from the north is drawn into the northern and western parts. Due to the rapid change of air masses during the passage of a cyclone, the weather also changes dramatically.

Anticyclone has the highest pressure at the center of the vortex. From here, the air spreads to the outskirts, deviating somewhat clockwise. The nature of the weather (slightly cloudy or dry - in a warm period, clear, frosty - in a cold one) persists throughout the entire time the anticyclone stays, since the air masses spreading from the center of the anticyclone have the same properties. In connection with the outflow of air in the surface part, air from the upper layers of the troposphere constantly enters the center of the anticyclone. As it descends, this air warms up and moves away from its saturation state. The weather in the anticyclone is clear, cloudless, with large daily

temperature fluctuations. Main the paths of cyclones are connected with atmospheric mifronts. In winter, they develop over the Barents, Kara and

Okhotskseas. To the districts intensive winter cyclones applies northwest Russian plains, where is the atlantic spirit interacts with the continent hoist moderate air latitudes and arctic.

In summer, cyclones are most intensively are developing in the Far East and in the western regions Russian plains. Some increase in cyclonic activity sti observed in the north of Siberia. Anticyclonic weather is most typical both in winter and summer for the south of the Russian Plain. Stable anticyclones are typical for winter Eastern Siberia.

Synoptic maps, weather forecast. synoptic car you contain weather information big territory. Compiling are they are for a certain period based weather observations, conducted network of meteorologists ical stations. At the synoptic sky charts show pressure air, weather fronts, areas high and low pressure and the direction of their movement, areas with precipitation and the nature of precipitation, wind speed and direction, air temperature. At present, satellite images are increasingly being used to compile synoptic maps. Cloudy zones are clearly visible on them, making it possible to judge the position of cyclones and atmospheric fronts. Synoptic maps are the basis for weather forecasting. For this purpose, maps compiled for several periods are usually compared, and changes in the position of fronts, displacement of cyclones and anticyclones are established, and the most probable direction of their development in the near future is determined. Based on these data, a weather forecast map is compiled, that is, a synoptic map for the upcoming period (for the next observation period, for a day, two). Small-scale maps give a forecast for a large area. The weather forecast is especially important for aviation. In a particular area, the forecast can be refined based on the use of local weather indicators.

1.2 Approach and passage of a cyclone

The first signs of an approaching cyclone appear in the sky. Even the day before, at sunrise and sunset, the sky is painted in a bright red-orange color. Gradually, as the cyclone approaches, it becomes copper-red, acquires a metallic hue. An ominous dark streak appears on the horizon. The wind freezes. There is an astonishing silence in the stuffy hot air. There is still about a day left before the moment when it flies

the first violent gust of wind. Seabirds hastily gather in flocks and fly away from the sea. Over the sea they will inevitably perish. With sharp cries, flying from place to place, the feathered world expresses its anxiety. Animals burrow into burrows.

But of all the harbingers of the storm, the most reliable is the barometer. Already 24 hours, and sometimes 48 hours before the start of the storm, the air pressure begins to fall.

The faster the barometer “falls”, the sooner and the stronger the storm will be. The barometer stops falling only when it is close to the center of the cyclone. Now the barometer begins to fluctuate without any order, now rising, then falling, until it passes the center of the cyclone.

Red or black patches of torn clouds rush across the sky. A huge black cloud is approaching with terrible speed; it covers the whole sky. Every minute, sharp, like a blow, gusts of a howling wind come up. Thunder, without ceasing, thunder; dazzling lightning pierces the ensuing darkness. In the roar and noise of a hurricane that has flown in, there is no way to hear each other. When the center of the hurricane passes, the noise begins to sound like artillery salvos.

Of course, even a tropical hurricane does not destroy everything in its path; he encounters many insurmountable obstacles. But how much destruction such a cyclone brings with it. All fragile, light buildings southern countries are sometimes destroyed to the ground and blown away by the wind. The water of the rivers, driven by the wind, flows backwards. Individual trees are uprooted and dragged along the ground for long distances. Branches and leaves of trees rush in clouds in the air. Age-old forests bend like reeds. Even grass is often swept away from the ground by a hurricane, like rubbish. Tropical cyclones hit hardest on sea ​​coasts. Here the storm passes without encountering great obstacles.

moving from warm regions to colder regions, cyclones gradually expand and weaken.

Individual tropical hurricanes sometimes go very far. Thus, the shores of Europe sometimes reach, however, greatly weakened tropical cyclones of the West Indies.

How do people now struggle with such formidable natural phenomena?

To stop a hurricane, to direct it along a different path, a person is not yet able to. But to warn about a storm, to inform ships at sea and the population on land about it - this task is successfully performed by the meteorological service in our time. Such a service draws up special weather maps on a daily basis, according to which

successfully predicts where, when and what strength a storm is expected in the coming days. Having received such a warning by radio, ships either do not leave the port, or rush to take refuge in the nearest reliable port, or try to get away from the hurricane.

We already know that when the front line between two air currents sags, a warm tongue is squeezed into the cold mass, and thus a cyclone is born. But the front line can sag in the direction of warm air. In this case, a vortex arises with completely different properties than a cyclone. It is called an anticyclone. This is no longer a hollow, but an air mountain.

The pressure in the center of such a vortex is higher than at the edges, and the air spreads from the center to the outskirts of the vortex. In its place, air descends from higher layers. As it descends, it contracts, heats up, and the cloudiness in it gradually dissipates. Therefore, the weather in the anticyclone is usually cloudy and dry; on the plains hot in summer And cold in winter. Only on the outskirts of the anticyclone can fogs and low stratus clouds occur. Since there is no such big difference in pressures, as in a cyclone, then the winds here are much weaker. They move clockwise (Fig. 4).

fig.4

As the vortex develops, its upper layers warm up. This is especially noticeable when the cold tongue is cut off and the whirlwind stops "feeding" on the cold, or when the anticyclone stagnates in one place. Then the weather in it becomes more stable.

In general, anticyclones are quieter eddies than cyclones. They move more slowly, about 500 kilometers per day; often stop and stand in one area for weeks, and then continue on their way again. Their sizes are huge. The anticyclone often, especially in winter, covers all of Europe and part of Asia. But in separate series of cyclones, small, mobile and short-lived anticyclones can also occur.

These whirlwinds usually come to us from the northwest, less often from the west. On weather maps, the centers of anticyclones are indicated by the letter B (Fig. 4).

On our map, we can find an anticyclone and see how the isobars are located around its center.

These are atmospheric vortices. Every day they pass over our country. They can be found on any weather map.

2. Studying atmospheric vortices at school

IN school curriculum about atmospheric vortices and air masses are studied in geography lessons.

At the lessons they study c circulation air masses in summer and winter, TtransformationYuair masses, and whenresearchatmosphericwhirlwindsstudycyclones and anticyclones, classification of fronts according to the features of movement, etc.

2.1 The study of atmospheric vortices in geography lessons

Sample lesson plan on the topic<< Air masses and their types. Circulation of air masses >> and<< atmospheric fronts. Atmospheric vortices: cyclones and anticyclones >>.

Air masses and their types. Air mass circulation

Target:to acquaint with various types of air masses, areas of their formation, types of weather determined by them.

Equipment:climatic maps of Russia and the world, atlases, stencils with the contours of Russia.

(Working with contour maps.)

1. Determine the types of air masses that dominate the territory of our country.

2. Identify the main properties of air masses (temperature, humidity, direction of movement).

3. Establish the areas of action of air masses and the possible influence on the climate.

(The results of the work can be entered in the table.)

Comments

1. Students should pay attention to the transformation of air masses when moving over a particular territory.

2. When checking the work of students, it must be emphasized that, depending on the geographical latitude, arctic, temperate or tropical air masses are formed, and depending on the underlying surface, they can be continental or marine.

Large masses of the troposphere, differing in their properties (temperature, humidity, transparency), are called air masses.

Three types of air masses move over Russia: arctic (AVM), temperate (UVM), tropical (TVM).

AVMform over the Arctic Ocean (cold, dry).

UVMformed in temperate latitudes. Above land - continental (KVUSH): dry, warm in summer and cold in winter. Over the ocean - marine (MKVUSH): wet.

Moderate air masses dominate in our country, since Russia is located mostly in temperate latitudes.

- How do the properties of air masses depend on the underlying surface? (Air masses that form over the sea surface are marine, wet, over land - continental, dry.)

- Are air masses moving? (Yes.)

Give evidence of their movement. (Changeweather.)

- What makes them move? (Difference in pressure.)

- Areas with different pressure the same throughout the year? (No.)

Consider the movement of air masses throughout the year.

If the movement of masses depends on the difference in pressure, then this diagram should first depict areas with high and low pressure. In summer, areas with high pressure located over the Pacific and Arctic oceans.

Summer

- What air masses are formed in these areas?(INArctic Arctic - continental arctic air masses (CAW).)

- What kind of weather do they bring? (They bring cold and clear weather.)

If this air mass passes over the mainland, then it heats up and transforms into a continental temperate air mass (TMA). Which already differs in properties from KAV (warm and dry). Then KVUSh turns into KTV (hot and dry, bringing dry winds and drought).

Transformation of air masses- this is a change in the properties of the air masses of the troposphere when moving to other latitudes and to another underlying surface (for example, from sea to land or from land to sea). At the same time, the air mass is heated or cooled, the content of water vapor and dust in it increases or decreases, the nature of cloudiness changes, etc. Under conditions of a fundamental change in the properties of air

its masses are attributed to another geographical type. For example, masses of cold arctic air, penetrating south of Russia in summer, become very warm, dry and dusty, acquiring the properties of continental tropical air, often causing droughts.

From the Pacific Ocean comes a moderate sea mass (MSW), it, like the air mass from the Atlantic Ocean, brings relatively cool weather and precipitation in summer.

Winter

(In this diagram, students also mark areas of high pressure (where there are areas of low temperature).)

Areas of high pressure are forming in the Arctic Ocean and in Siberia. From there, cold and dry air masses are sent to the territory of Russia. From the side of Siberia, continental moderate masses come, bringing frosty clear weather. Maritime air masses in winter come from Atlantic Ocean which at this time is warmer than the mainland. Consequently, this air mass brings precipitation in the form of snow, thaws and snowfalls are possible.

Answer the question: “How would you explain the type of weather today? Where did he come from, by what signs did you determine this?

atmospheric fronts. Atmospheric vortices: cyclones and anticyclones

Goals:form an idea of ​​atmospheric vortices, fronts; show the relationship between weather changes and processes in the atmosphere; Explain the reasons for the formation of cyclones and anticyclones.

Equipment:maps of Russia (physical, climatic), demonstration tables "Atmospheric fronts" and "Atmospheric vortices", cards with points.

1. Frontal survey

- What are air masses? (Large volumes of air that differ in their properties: temperature, humidity and transparency.)

- Air masses are divided into types. Name them, how are they different? ( Sample answer. Arctic air is formed over the Arctic - it is always cold and dry, transparent, because there is no dust in the Arctic. Over most of Russia in temperate latitudes, a moderate air mass is formed - cold in winter and warm in summer. In summer, tropical air masses come to Russia, which form over the deserts of Central Asia and bring hot and dry weather with air temperatures up to 40 ° C.)

- What is air mass transformation? ( Sample answer. Changes in the properties of air masses during their movement over the territory of Russia. For example, temperate marine air coming from the Atlantic Ocean loses moisture, warms up in summer and becomes continental - warm and dry. In winter, maritime temperate air loses moisture, but cools and becomes dry and cold.)

- Which ocean and why has a greater influence on the climate of Russia? ( Sample answer. Atlantic. First, most of Russia

is located in the prevailing western wind transfer, and secondly, there are practically no obstacles for the penetration of western winds from the Atlantic, since there are plains in the west of Russia. The low Ural Mountains are not an obstacle.)

2. Test

1. The total amount of radiation reaching the Earth's surface is called:

a) solar radiation;

b) radiation balance;

c) total radiation.

2. The largest indicator of reflected radiation has:

a) sand c) black soil;

b) forest; d) snow.

3.Move over Russia in winter:

a) arctic air masses;

b) moderate air masses;

c) tropical air masses;

d) equatorial air masses.

4. The role of the western transport of air masses is increasing in most of Russia:

in the summer; c) autumn.

b) in winter;

5. The largest indicator of total radiation in Russia has:

a) south of Siberia; c) south Far East.

b) North Caucasus;

6. The difference between total radiation and reflected radiation and thermal radiation is called:

a) absorbed radiation;

b) radiation balance.

7. When moving towards the equator, the amount of total radiation:

a) is decreasing c) does not change.

b) increases;

Answers:1 - in; 3 - g; 3 - a, b; 4 - a; 5 B; 6 - b; 7 - b.

3. Card work And

Determine what type of weather is being described.

1. At dawn, the frost is below 35 ° C, and the snow is barely visible through the fog. The creak can be heard for several kilometers. The smoke rises vertically from the chimneys. The sun is red like hot metal. During the day, the sun and snow sparkle. The fog has already cleared. The sky is blue, permeated with light, if you look up, it seems like summer. And it’s cold outside, severe frost, the air is dry, there is no wind.

The frost is getting stronger. A rumble is heard from the sounds of cracking trees in the taiga. In Yakutsk average temperature January -43 ° C, and from December to March, an average of 18 mm of precipitation falls. (Continental temperate.)

2. The summer of 1915 was very rainy. It rained all the time with great constancy. Once, for two days in a row, it went very heavy rain. He did not allow people to leave their houses. Fearing that the boats would be carried away by water, they pulled them further ashore. Several times in one day

overturned them and poured out the water. By the end of the second day, water suddenly came from above in a shaft and immediately flooded all the banks. (Monsoon moderate.)

III. Learning new material

Comments.The teacher offers to listen to a lecture, during which students define terms, fill in tables, make diagrams in a notebook. Then the teacher, with the help of consultants, checks the work. Each student receives three score cards. If within

lesson, the student gave the score card to the consultant, which means that he still needs to work with a teacher or consultant.

You already know that three types of air masses move in our country: arctic, temperate and tropical. They are quite different from each other in terms of the main indicators: temperature, humidity, pressure, etc. When air masses approach each other, having

different characteristics, in the zone between them the difference in air temperature, humidity, pressure increases, the wind speed increases. Transitional zones in the troposphere, in which air masses approach each other different characteristics, are called fronts.

In the horizontal direction, the length of the fronts, as well as air masses, is thousands of kilometers, along the vertical - about 5 km, the width of the frontal zone near the Earth's surface is about a hundred kilometers, at altitudes - several hundred kilometers.

The time of existence of atmospheric fronts is more than two days.

Fronts, together with air masses, move at an average speed of 30-50 km/h, and the speed of cold fronts often reaches 60-70 km/h (and sometimes 80-90 km/h).

Classification of fronts according to the features of movement

1. Warm fronts are those moving towards colder air. A warm air mass moves into the region behind a warm front.

2. Cold fronts are called fronts moving towards a warmer air mass. A cold air mass moves into the region behind a cold front.

IV. Fixing new material

1. Working with the map

1. Determine where the arctic and polar fronts are located over the territory of Russia in summer. (Example answer). Arctic fronts in summer are located in the northern part of the Barents Sea, over the northern part of Eastern Siberia and the Laptev Sea, and over the Chukchi Peninsula. Polar fronts: the first in summer stretches from the Black Sea coast over the Central Russian Upland to the Cis-Urals, the second is located in the south

Eastern Siberia, the third - over the southern part of the Far East and the fourth - over the Sea of ​​Japan.)

2 . Determine where arctic fronts are located in winter. (In winter, the arctic fronts shift to the south, but remainfront over the central part of the Barents Sea and over the Sea of ​​Okhotsk and the Koryak Highlands.)

3. Determine in which direction the fronts shift in winter.

(Example answer).In winter, the fronts move south, because all air masses, winds, pressure belts move south following the visible movement

Sun.

2. Independent work

Filling tables.

atmospheric fronts

Cyclones and anticyclones

3. Working with synoptic maps (weather maps)

Thanks to synoptic maps, one can judge the progress of cyclones, fronts, clouds, make a forecast for the next hours, days. Synoptic maps have their own symbols, by which you can find out about the weather in any area. Isolines connecting points with the same atmospheric pressure (they are called isobars) show cyclones and anticyclones. In the center of the concentric isobars is the letter H (low pressure, cyclone) or IN(high pressure, anticyclone). The isobars also indicate the air pressure in hectopascals (1000 hPa = 750 mm Hg). The arrows show the direction of motion of the cyclone or anticyclone.

The teacher shows how the synoptic map reflects various information: air pressure, atmospheric fronts, anticyclones and cyclones and their pressure, areas with precipitation, precipitation patterns, wind speed and direction, air temperature.)

From the suggested signs, choose what is typical for

cyclone, anticyclone, atmospheric front:

1) atmospheric vortex with high pressure in the center;

2) atmospheric vortex with low pressure in the center;

3) brings cloudy weather;

4) stable, inactive;

5) installed over Eastern Siberia;

6) zone of collision of warm and cold air masses;

7) ascending air currents in the center;

8) downward movement of air in the center;

9) movement from the center to the periphery;

10) movement counterclockwise to the center;

11) is hot and cold.

(Cyclone - 2, 3, 1, 10; anticyclone - 1, 4, 5, 8, 9; atmospheric front - 3,6, 11.}

Homework

2.2 Study of the atmosphere and atmospheric phenomena from grade 6

The study of the atmosphere and atmospheric phenomena at school begins in the sixth grade in geography lessons.

From the sixth grade, students studying the section of geography<< Атмосфера – воздушная оболочка земли>> begin to explore the composition and structure of the atmosphere, in particular, the fact that the force of gravity of the earth holds this air shell around itself and prevents it from dissipating in space, students also begin to understand that clean air is the most important condition for human life. They begin to distinguish the composition of the air, gain knowledge about oxygen and learn how important it is for a person in its pure form. They get knowledge about the layers of the atmosphere, and how important it is for the globe, from which it protects us.

Continuing the study of this section, students will understand that the air at the surface of the earth is warmer than at a height and this is due to the fact that the sun's rays, passing through the atmosphere, almost do not heat it up, only the surface of the earth heats up, and if there was no atmosphere, then the surface of the earth

would quickly give off the heat received from the sun, given this phenomenon, the children imagine that our earth is protected by its air shell, in particular air, retains part of the heat leaving the earth's surface and heats up at the same time. And if you go higher, then there the layer of the atmosphere becomes thinner and, therefore, it cannot retain more heat.

Already having an idea of ​​​​the atmosphere, children continue to explore and find out that there is such a thing as an average daily temperature, and it is found by a very simple method - they measure the temperature during the day for a certain period of time, then from the collected indicators they find the arithmetic mean.

Now schoolchildren, moving on to the next paragraph of the section, begin to study the morning and evening cold, and this is so, because during the day the sun rises to its maximum height, and at this moment the maximum heating of the earth's surface occurs. And as a result, the difference between air temperatures during the day can change, in particular over the oceans and seas 1-2 degrees, and over the steppes and deserts can reach up to 20 degrees. This takes into account the angle of incidence of sunlight, terrain, vegetation and weather.

Continuing to consider this paragraph, students learn that why it is warmer in the tropics than at the pole, and this is so, because the farther from the equator, the lower the sun is above the horizon, and therefore the angle of incidence of the sun's rays on the earth is less, and less solar energy per unit of earth's surface.

Moving on to the next paragraph, students begin to study pressure and wind, consider issues such as Atmosphere pressure what determines the air pressure, why the wind blows and what it happens.

Air - has a mass, according to scientists, a column of air presses on the surface of the earth with a force of 1.03 kg / cm 2. Atmospheric pressure is measured using a barometer, and the unit of measure is millimeters of mercury.

Normal pressure is 760 mm Hg. Art., therefore, if the pressure is above the norm, it is called increased, and if it is lower, it is called reduced.

There is an interesting pattern here, atmospheric pressure is in equilibrium with the pressure inside the human body, so we do not experience inconvenience, despite the fact that such a volume of air presses on us.

Now let's consider what the air pressure depends on, and so, with an increase in the height of the terrain, the pressure decreases, and this, because the less air column pressing on the ground, the air density also decreases, therefore, the higher from the surface, the more difficult it is to breathe.

Warm air is lighter than cold air, its density is lower, the pressure on the surface is weak, and when heated, warm masses rise up, and the reverse process occurs if the air cools.

Analyzing the above, it follows that atmospheric pressure is closely related to air temperature and altitude.

Now let's move on to the next question, and find out why the wind blows?

In the middle of the day, sand or stone is heated in the sun, and the water is still quite cool - it heats up more slowly. And in the evening or at night it can be the other way around: the sand is already cold, but the water is still warm. This is because land and water heat up and cool down differently.

During the day, the sun's rays heat the coastal land. At this time: land, buildings on it, and from them the air heats up faster than water, warm air rises above land, pressure over land decreases, air over water does not have time to heat up, its pressure is still higher than over land, air from the area higher pressure above the water tends to take a place above the land and begins to move, equalizing the pressure - from the sea to land it blew wind.

At night, the surface of the earth begins to cool. The land and the air above it cool faster, and the pressure over land becomes higher than over water. The water cools more slowly, and the air above it remains warm longer. It rises, and the pressure over the sea decreases. The wind starts to blow

sushi by the sea. Such a wind that changes direction twice a day is called a breeze (translated from French as a light wind).

Now the students already know that WIND IS DUE TO THE DIFFERENCE IN THE ATMOSPHERIC PRESSURE IN DIFFERENT PARTS OF THE EARTH'S SURFACE.

And after that, students can already explore the next question. What is the wind like? The wind has two main characteristics: speed And direction. The direction of the wind is determined by the side of the horizon from which it blows, and the wind speed is the number of meters traveled by air per second (m / s).

For each area, it is important to know which winds blow more often, which ones less often. It is essential for building designers, pilots and even doctors. Therefore, experts build a drawing, which is called the wind rose. Initially, the wind rose was a sign in the form of a star, the rays of which pointed to the sides of the horizon - 4 main and 8 intermediate. The top beam always pointed north. The wind rose was present on old maps and compass dials. She pointed the direction to sailors and travelers.

Moving on to the next paragraph, students begin to explore moisture in the atmosphere.

Water is present in all earthly shells, including the atmosphere. She gets there evaporating from the water and solid surface of the earth and even from the surface of plants. Along with nitrogen, oxygen and other gases, the air always contains water vapor - water in a gaseous state. Like other gases, it is invisible. As the air cools, the water vapor it contains turns into droplets. condenses. Small particles of water condensed from water vapor can be observed as clouds high in the sky or as fog low above the earth's surface.

At negative temperatures, the droplets freeze - they turn into snowflakes or ice floes.Now considerWhich air is humid and which is dry?The amount of water vapor that can be contained in the air depends on its temperature. For example, 1 m 3 of cold air at a temperature of about -10 ° C can contain a maximum of 2.5 g of water vapor. However, 1 m 3 of equatorial air at a temperature of +30 ° C can contain up to 30 g of water vapor. How higher air temperature, the more water vapor it may contain.

Relative Humidity shows the ratio of the amount of moisture in the air to the amount that it can contain at a given temperature.

How do clouds form and why does it rain?

What will happen if the air saturated with moisture cools? Part of it will turn into liquid water, because colder air can hold less water vapor. On a hot summer day, one can observe how at first a little, and then more and more large clouds appear in a cloudless sky in the morning. It is the sun's rays that heat the earth more and more, and the air heats up from it. The heated air rises, cools, and the water vapor in it turns into a liquid state. Initially, these are very small droplets of water (hundredths of a millimeter in size). Such drops do not fall to the ground, but "float" in the air. This is how clouds. As the drops increase in number, they can increase in size and finally fall to the ground as rain or fall as snow or hail.

The "fluffy" clouds formed when air rises as a result of surface heating are called cumulus. The pouring rain comes from powerful cumulonimbus clouds. There are other types of clouds - low

layered, taller and lighter pinnate. Heavy precipitation falls from nimbostratus clouds.

Cloudinessis an important characteristic of the weather. This is the portion of the sky occupied by clouds. Cloudiness determines how much light and heat will not reach the surface of the earth, how much precipitation will fall. Cloudiness at night prevents a decrease in air temperature, and during the day it weakens the heating of the earth by the sun.

Now consider the question - what are the precipitations? We know that precipitation falls from clouds. Precipitation is liquid (rain, drizzle), solid (snow, hail) and mixed - sleet (snow with rain). An important characteristic of precipitation is its intensity, i.e., the amount of precipitation that has fallen over a certain period of time, in millimeters. The amount of precipitation on the earth's surface is determined using a rain gauge. According to the nature of the fallout, torrential, continuous and drizzling precipitation are distinguished. Stormwater precipitation is intense, short-lived, falling from cumulonimbus clouds. Complimentary Precipitation falling from nimbostratus clouds is moderately intense and long in time. Drizzling precipitation falls from stratus clouds. They are small droplets, as if suspended in the air.

Having studied the above, students proceed to consider the issue - What are air masses? In nature, almost always "everything is connected with everything", so the elements of the weather do not change arbitrarily, but in interconnection with each other. Their stable combinations characterize various types air masses. The properties of air masses, firstly, depend on the geographical latitude, and secondly, on the nature of the earth's surface. The higher the latitude, the less heat, the lower the air temperature.

At the end, students will learn thatclimate - long-term weather pattern characteristic of a particular area.

Mainclimate factors: geographic latitude, proximity to seas and oceans, direction prevailing winds, relief and height above sea level, sea currents.

Further study of climatic phenomena by schoolchildren continues at the level of the continents separately, they consider separately what phenomena occur on which continent, and having studied on the continents, in high school they continue to consider separately taken countries

Conclusion

Atmosphere - an air shell that surrounds the earth and rotates with it. The atmosphere protects life on the planet. It retains the heat of the sun and protects the earth from overheating, harmful radiation, and meteorites. It forms the weather.

The air of the atmosphere consists of a mixture of gases, it always contains water vapor. The main gases in the air are nitrogen and oxygen. The main characteristics of the atmosphere are air temperature, atmospheric pressure, air humidity, wind, clouds, precipitation. The air shell is connected with other shells of the Earth primarily through the global water cycle. The bulk of the atmospheric air is concentrated in its lower layer - the troposphere.

Solar heat arrives at the spherical surface of the earth unequally, so different climates are formed at different latitudes.

Bibliography

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