Constant winds over the earth's surface. Types of winds, causes of wind formation. Mechanisms for the formation of permanent winds

1. On the globe, show the location of the low and high pressure belts. Which of them are dominated by upward movement of air, which are descending, and what effect does this have on precipitation?

You have already seen that there is a relationship between atmospheric pressure and precipitation. With an upward movement of air, the conditions for the occurrence of precipitation are greater than with a downward one. Changes in pressure must be taken into account in the weather forecast. If a stable elevated atmospheric pressure has formed, then the weather is clear (hot in summer and frosty in winter), and if the pressure changes sharply from high to low, then the weather also changes sharply, the wind increases, and precipitation forms.

2. Name the constant winds over the earth's surface and explain their formation.

Trade winds and westerly winds of temperate latitudes. In addition to them, monsoons belong to the constant winds. Remember how the summer and winter monsoons blow. The reason for the formation of all winds is the difference in atmospheric pressure. The greater the difference between the pressures, the greater the wind speed.

3. What effect do air currents have on climate?

Each climate zone has its own circulation of air masses. In the main climatic zones, as a rule, the air mass corresponding to the name of this zone dominates (in the equatorial - equatorial air masses, in the tropical - tropical, in the temperate - temperate, in the arctic - arctic, and antarctic - antarctic).

4. How do transitional belts differ from the main ones?

In transitional zones (subtropical, subequatorial, subarctic and subantarctic) air masses change depending on the season of the year. In summer there is a global shift of the entire circulation to the north, in winter - to the south. Thus, subtropical and even tropical air masses can enter the temperate zone in summer, and subarctic and arctic air masses in winter.

5. What are the patterns of temperature distribution, as well as precipitation on Earth?

Having studied the climate map, it is possible to identify some regularities in the distribution of heat and moisture over the Earth's surface. The amount of heat received by the Earth's surface increases as it approaches the equator. Precipitation also falls more around the equator on the southeastern coasts of the continents.

6. Why are scientists around the world concerned about the state of the atmosphere?

The state of the Earth's atmosphere has changed dramatically over the past 1000 years. The amount of carbon dioxide and other pollutants in the atmosphere has increased. This led to the emergence of a "greenhouse effect" and a gradual warming of the climate, which worries scientists very much, since the consequences threaten the lives of the entire population of the Earth.

1. On the globe, show the location of the low and high pressure belts. Which of them are dominated by ascending air movement, which are descending, and what effect does this have on precipitation?

You will be able to complete the first part of the task yourself, relying on the text and drawings in the textbook (7, fig. 16, 17).

You have already seen that there is a relationship between atmospheric pressure and precipitation. With an upward movement of air, the conditions for the occurrence of precipitation are greater than with a downward one. Changes in pressure must be taken into account in the weather forecast. If a stable elevated atmospheric pressure has formed, then the weather is clear (hot in summer and frosty in winter), and if the pressure changes sharply from high to low, then the weather also changes sharply, the wind increases, and precipitation forms.

2. How does the weather in your area change with increasing or decreasing atmospheric pressure?

You will be able to answer this question yourself, based on our reasoning, as well as on the text and figures in the textbook (7, 8).

3. Name the constant winds over the earth's surface and explain their formation.

In 7 of the textbook, such constant winds as the trade winds and westerly winds of temperate latitudes have already been named. In addition to them, monsoons belong to the constant winds. Remember how the summer and winter monsoons blow. The reason for the formation of all winds is the difference in atmospheric pressure. The greater the difference between the pressures, the greater the wind speed.

4. What causes frequent weather changes in your area?

You will be able to answer this question yourself, based on the text and pictures in the textbook (7, 8), as well as messages

about the weather in your area on radio and television.

5. What effect do air currents have on climate?

Each climate zone has its own circulation of air masses. In the main climatic zones, as a rule, the air mass corresponding to the name of this zone dominates (in the equatorial - equatorial air masses, in the tropical - tropical, in the temperate - temperate, in the arctic - arctic, and antarctic - antarctic).

6. How do transitional belts differ from the main ones?

In transitional zones (subtropical, subequatorial, subarctic and subantarctic) air masses change depending on the season of the year. In summer, there is a global shift of the entire circulation to the north, in winter - to the south. Thus, subtropical and even tropical air masses can enter the temperate zone in summer, and subarctic and arctic air masses in winter.

7. What climate zone do you live in?
8. What weather prevails in the tropical zone?

You can answer these questions yourself, based on the text and pictures in the textbook (7, 8) and the maps of the school atlas.

9. What are the patterns of temperature distribution, as well as precipitation on Earth?

Having studied the climate map, it is possible to identify some regularities in the distribution of heat and moisture over the Earth's surface. The amount of heat received by the Earth's surface increases as it approaches the equator. Precipitation also falls more around the equator on the southeastern coasts of the continents.

10. Why do scientists around the world worry about the state of the atmosphere?

The state of the Earth's atmosphere has changed dramatically over the past 1000 years. The amount of carbon dioxide and other pollutants in the atmosphere has increased. This led to the emergence of a "greenhouse effect" and a gradual warming of the climate, which worries scientists very much, since the consequences threaten the lives of the entire population of the Earth.

Name the constant winds over the earth's surface and explain their formation. and got the best answer

Answer from YaisiyaKonovalova[guru]
trade winds, monsoons, breezes.

Answer from Hrazayeva Tamila[newbie]
At some latitudes of the Earth there are belts of high and low pressure. For example, atmospheric pressure is lower above the equator because the surface of the earth is very hot there. Strong global winds, called Westerly winds and trade winds, blow from high pressure belts towards low pressure belts. They do not, however, move directly from south to north and from north to south. This is due to the fact that the rotation of the Earth forces the global winds to turn to the side.

Answer from DEMENKOV'S AVATARIA[newbie]
about

Answer from Kazimagomed Gadzhibekov[master]
Google to help .. but in general this is an easy question ... the topic of the 6th grade.

Answer from skyrim skyrim[newbie]
trade winds, monsoons, breezes.
The trade winds are formed due to the pressure difference in the tropical regions of both hemispheres and at the equator. These winds are deflected by the rotation of the Earth: the trade winds of the northern hemisphere blow from the northeast to the southwest, and the trade winds of the south blow from the southeast to the northwest. They are quite stable in temperature and humidity and are one of the most important factors in climate formation.
Monsoons are formed due to pressure differences resulting from temperature differences. A distinctive feature of the monsoons is that in the warm and cold seasons they are directed in opposite directions: from the sea to land and from land to sea. In winter, the air over the sea is warmer than over land, the atmospheric pressure over the sea is lower, therefore, the monsoons are directed from land to sea. In the warm season, the opposite is true: the air is warmer over land, and an area of ​​low pressure forms there. Monsoons at this time blow on land and bring with them heavy rainfall.
In the tropical zone, monsoons are especially active, but they also exist outside the tropics. Areas dominated by monsoons are characterized by very wet summers. A great example of the impact of the monsoons is India, where the Himalayan mountains stop the damp wind, so in northern India, Burma, Nepal, there is a huge amount of precipitation.
Breezes, like monsoons, change their direction to the opposite, but this happens with a frequency of a day. These are not very large-scale winds, they are formed near the seas, oceans, large lakes, rivers. During the day, the air above the land heats up, the warm air rises, and in its place cooler air comes from the water. At night, on the contrary, it is warmer above the water, colder air masses come here from land. Thus, during the day the breeze blows from water to land, and at night from land to water.

Answer from Al.[guru]
the first cat is right actually!!! !
lazy you! not such a difficult question!
okay... I'll help you with one kind of winds... .
if you know, warm air goes up and cold air goes down.
because of this constant mixing SOME of the winds are formed
another thing... so de interesting is that ALL big whirlwinds, tornadoes and hurricanes spin IN A CERTAIN PATTERN that is known to people who know about the CORIOLIS force. (a scientist)
all LARGE air eddies in the northern hemisphere will be twisted COUNTER-CLOCK
and in the southern hemisphere clockwise.
I won't explain everything. it's physics. I had an hour and a half report on this issue at the university)
good luck)

The general circulation of the atmosphere includes trade winds, westerly winds of moderate latitudes, easterly (katabatic) winds of the polar regions, as well as monsoons.

Wind is caused by differences in atmospheric pressure. Since there are relatively constant belts on the Earth, they also depend on them. prevailing winds(also called permanent, predominant, dominant or predominant).

Air masses moving with steady winds move in a certain order. They also create a complex system of air currents on a global scale. It is called the general circulation of the atmosphere (from the Latin word circulation- rotation).

Between the atmospheric pressure belts of the earth, relatively stable prevailing winds, or winds of prevailing directions, are formed.

trade winds

Among the constant winds, the most famous are - trade winds.

trade winds - winds that are stable throughout the year, directed from tropical latitudes to equatorial latitudes and generally have an easterly direction.

The trade winds are formed in a hot thermal zone and blow from an area of ​​high pressure in the region of 30 ° N. sh. and 30°S sh. towards the equator - areas with lower pressure (Fig. 31). If the Earth did not rotate, then the winds in the Northern Hemisphere would blow exactly from north to south. But due to the rotation of the Earth, the winds deviate from the direction of their movement: in the Northern Hemisphere - to the right, and in the Southern Hemisphere - to the left. This phenomenon is called the Coriolis effect - after the French scientist, and it manifests itself in relation not only to winds, but also, for example, sea currents and erosion of the corresponding banks of large rivers (in the Northern Hemisphere - right, in the Southern - left).

The Northern Hemisphere trade wind is a northeasterly wind, and the Southern Hemisphere trade wind is a southeasterly wind.

The trade winds blow at a fairly high speed, about 5-6 m / s, and weaken, converging near the equator - a calm zone is formed there. The trade winds over the Ocean are distinguished by a special constancy. This was noted by seafarers of the past, who sailed on sailing ships and were very dependent on the winds. It is believed that the name "trade wind" comes from the Spanish vientedepasada, which means "the wind that favors the move." Indeed, in the days of the sailing fleet, they helped to travel from Europe to America.

Western winds of temperate latitudes

From the high pressure area of ​​the hot belt, winds blow not only towards the equator, but also in the opposite direction - towards temperate latitudes, where the low pressure belt is also located. These winds, like the trade winds, are deflected by the rotation of the Earth (the Coriolis effect). In the Northern Hemisphere they blow from the southwest, and in the Southern Hemisphere from the northwest. Therefore these winds are called westerly winds of temperate latitudes or western carry(Fig. 31).

With the western transfer of air masses, we constantly encounter in our latitudes in Eastern Europe. With westerly winds, sea air from temperate latitudes most often comes to us from the Atlantic. In the Southern Hemisphere of latitude, where westerly winds form over the giant continuous surface of the Ocean and reach tremendous speed, they are called "roaring forties". material from the site

Eastern (katabatic) winds of the polar regions

Eastern (katabatic) winds of the polar regions blow towards low pressure belts of temperate latitudes.

Monsoons

Steady winds are often referred to as monsoons. Monsoons arise due to the uneven heating of land and ocean in summer and winter. The land area is much larger in the Northern Hemisphere. Therefore, monsoons are well pronounced here on the eastern coasts of Eurasia and North America, where in the middle latitudes there is a significant contrast in the warming of land and ocean. A special variety is the tropical monsoons that dominate South and Southeast Asia.

Unlike other prevailing winds, monsoons are seasonal winds. They change direction twice a year. The summer monsoon blows from the ocean to the land and brings moisture (rainy season), while the winter monsoon blows from land to the ocean (dry season).

On this page, material on the topics:

• The prevailing winds of all belts

• Mechanisms for the formation of permanent winds

• At what latitudes do westerly winds blow?

• The direction of the trade winds and westerly winds of temperate latitudes

• Prevailing winds and their movement across latitudes

Questions about this item:

wind formation

Although the air is invisible to the eye, we always feel its movement - the wind. The main reason for the occurrence of wind is the difference in atmospheric pressure over areas of the earth's surface. As soon as the pressure somewhere decreases or increases, the air will move from the place of greater pressure to the side of less. And the pressure equilibrium is disturbed by the unequal heating of various parts of the earth's surface, from which the air also heats up differently.

Let's try to imagine how this happens on the example of the wind that occurs on the coasts of the seas and is called breeze. Areas of the earth's surface - land and water - are heated differently. Dry dol heats up faster. Therefore, the air above it will heat up faster. It will rise up, the pressure will decrease. Over the sea at this time, the air is colder and, accordingly, the pressure is higher. Therefore, air from the sea moves to land in place of warm air. Here the wind blew - afternoon breeze. At night, everything happens the other way around: the land cools faster than the water. Above it, cold air creates more pressure. And above the water, it retains heat for a long time and cools slowly, the pressure will be lower. Cold air from the land moves from the area of ​​high pressure towards the sea, where the pressure is lower. Arises night breeze.

Therefore, the difference in atmospheric pressure acts as a force, causing horizontal movement of air from an area of ​​high pressure to an area of ​​low pressure. This is how the wind is born.

Determination of wind direction and speed

The direction of the wind is determined beyond the side of the horizon from which it blows. If, for example, the wind blows from the event, it is called westerly. This means that the air moves from west to east.

Wind speed depends on atmospheric pressure: the greater the difference in pressure between areas of the earth's surface, the stronger the wind. It is measured in meters per second. Near the earth's surface, winds often blow at a speed of 4-8 m / s. In ancient times, when there were no instruments yet, the speed and strength of the wind was determined by local signs: at sea - by the action of the wind on the water and sails of ships, on land - by the tops of trees, by the deflection of smoke from pipes. For many features, a 12-point scale was developed. It allows you to determine the strength of the wind in points, and then its speed. If there is no wind, its strength and speed are equal to zero, then this is calm. Wind with a force of 1 point, barely swaying the leaves of trees, is called quiet. Next on the scale: 4 points - moderate wind(5 m / s), 6 points - strong wind(10 m / s), 9 points - storm(18 m/s), 12 points - Hurricane(Over 29 m/s). At weather stations, the strength and direction of the wind is determined using weather vane, and the speed is anemometer.

The strongest winds near the earth's surface blow in Antarctica: 87 m / s (individual gusts reached 90 m / s). The highest wind speed in Ukraine was recorded in the Crimea on grief- 50 m / s.

Monsoon is a periodic wind that carries a large amount of moisture, blowing from land to ocean in winter, and from ocean to land in summer. Monsoons are observed mainly in the tropical zone. Monsoons are seasonal winds that last for several months each year in tropical areas. The term originated in British India and nearby countries as the name for the seasonal winds that blow from the Indian Ocean and the Arabian Sea to the northeast, bringing significant amounts of precipitation to the region. Their movement towards the poles is caused by the formation of low pressure areas as a result of the heating of tropical regions during the summer months, that is, Asia, Africa and North America from May to July and Australia in December.

The trade winds are constant winds blowing with a fairly constant force of three or four points; their direction practically does not change, only slightly deviating. The trade winds are called the near-surface part of the Hadley cell - the predominant near-surface winds that blow in the tropical regions of the Earth in a westerly direction, approaching the equator, that is, northeast winds in the Northern Hemisphere, and southeast winds in the South. The constant movement of the trade winds leads to the mixing of the Earth's air masses, which can manifest itself on a large scale: for example, the trade winds blowing over the Atlantic Ocean are capable of carrying dust from the African deserts to the West Indies and parts of North America.

Local winds:

Breeze - a warm wind blowing from the coast to the sea at night and from the sea to the coast during the day; in the first case it is called a coastal breeze, and in the second - a sea breeze. Important effects of the formation of predominant winds in coastal areas are sea and continental breezes. The sea (or smaller body of water) heats up more slowly than land due to the greater heat capacity of water. Warmer (and therefore lighter) air rises over land, creating zones of low pressure. As a result, a pressure difference is formed between land and sea, which is usually 0.002 atm. Due to this pressure difference, the cool air over the sea moves towards the land, creating a cool sea breeze on the coast. Due to the lack of stronger winds, the speed of the sea breeze is proportional to the temperature difference. If there is wind from the land side with a speed of more than 4 m/s, the sea breeze usually does not form.

At night, due to the lower heat capacity, the land cools faster than the sea, and the sea breeze stops. When the temperature of the land falls below the temperature of the surface of the reservoir, a reverse pressure drop occurs, causing (in the absence of a strong wind from the sea) a continental breeze that blows from the land to the sea.

Bora is a cold, sharp wind blowing from the mountains to the coast or valley.

Foehn - a strong warm and dry wind blowing from the mountains to the coast or valley.

Sirocco is the Italian name for a strong southerly or southwesterly wind that originates in the Sahara.

Variable and constant winds

variable winds change their direction. These are the sprays already known to you (from the French "Breeze" - light wind). They change their direction twice a day (day and night). Splashes occur not only on the coasts of the seas, but also on the shores of large lakes and rivers. However, they cover only a narrow strip of the coast, penetrating deep into the land or sea for several kilometers.

Monsoons formed in the same way as breezes. But they change their direction twice a year according to the seasons (summer and winter). Translated from Arabic, "monsoon" means "Season". In summer, when the air over the ocean heats up slowly and the pressure over it is greater, moist sea air penetrates the land. This is the summer monsoon that brings daily thunderstorms. And in winter, when high air pressure is established over land, the winter monsoon begins to operate. It blows from land towards the ocean and brings cold, dry weather. So, the reason for the formation of monsoons is not daily, but seasonal fluctuations in air temperature and atmospheric pressure over the mainland and ocean. Monsoons penetrate the land and ocean for hundreds and thousands of kilometers. They are especially common on the southeastern coast of Eurasia.

Unlike variables, constant winds blow in the same direction throughout the year. Their formation is associated with high and low pressure belts on Earth.

trade winds- Winds that blow throughout the year from high pressure zones near the 30th tropical latitudes of each hemisphere to a low pressure zone at the equator. Under the influence of the rotation of the Earth around its axis, they are not directed directly to the equator, but deviate and blow from the northeast in the Northern Hemisphere and from the southeast - in the Southern Hemisphere. The trade winds, characterized by uniform speed and amazing constancy, were the favorite winds of navigators.

From tropical zones of high pressure, winds blow not only towards the equator, but also in the opposite direction - towards the 60th latitude with low pressure. Under the influence of the deflecting force of the Earth's rotation, with distance from tropical latitudes, they gradually deviate to the east. This is how air moves from west to east and these winds in temperate latitudes become Western.