Windiness in the modern dictionary is synonymous with impermanence, changeability. But the trade winds this statement is completely broken. Unlike breeze, seasonal monsoons and even more winds caused by weather cyclones, they are constant. How are trade winds formed and why blow in a strictly defined direction? Where did this word come from in our tongue? Are these winds that are constant and where are they localized? You will learn about this and many other things from this article.

The meaning of the word "trade winds"

During the time of sailing fleet, the wind was of paramount importance for navigation. When he exactly blends always in the same direction, it was possible to hope for a safe outcome of a dangerous journey. And such a wind Spanish navigators dubbed "Viento de Pasade" - favorable movement. The Germans and the Dutch included the word "Pasad" in their marine dictionary of navigation terms (Passat and Passaat). And in the era of Peter the first, this name penetrated into Russian. Although in our high latitudes, the trade winds are rare. The main place of their "habitat" - between two tropics (cancer and Capricorn). Passats are observed and further from them - up to the thirtieth degree. At a considerable distance from the equator, these winds lose their strength and are observed only on large open spaces, above the oceans. There they are blowing by force in 3-4 points. At the shores of the trade winds are transformed into monsoons. And further from the equator, the location of the winds generated by cyclonic activity is inferior.

How the Passat is formed

We will conduct a small experiment. I appline a few drops on the ball. And now we will spin it as Yulia. Look at the drops. Those of them, which are closer to the axis of rotation, remained real estate, and located on board "Yula" spread out in the opposite direction. Now imagine that the ball is our planet. She spins from west to east. From this movement are formed opposite winds. When the point is located close to the poles, per day it makes a smaller circle than the one that is at the equator. Therefore, the speed of its movement around the axis is slower. From friction with an atmosphere in such sugar lathes does not occur air currents. Now it is clear that the trade winds are stable treropic winds. At the same equator, the so-called strip of the calm is observed.

Passatov direction

Drops on the ball it is not difficult to trace that they spread in the direction, reverse rotation. It is called but to say that Passats are winds that will be wrong from the east. In practice, in the air masses deviate from their main vector south. The same thing happens, only in mirror reflection, on the other side of the equator. That is, in the southern hemisphere, the Passats blow from the south-east to the north-west.

Why is the equator so attractive for air masses? In the tropics, as is known, the constant area of \u200b\u200bhigh pressure is established. And the equator, on the contrary, is low. If we are responsible for a children's question, where the wind comes from, then we will put up the capital's naturalistic truth. The wind is the movement of air masses from high pressure layers to the area with lower. The periphery of the tropics in science is called "horsepower latitude". From there a gallop blowing the trade winds in the "Style Led" above the equator.

Speed \u200b\u200bof constant winds

So, we understood the range of distribution of trade winds. They are formed in both on a latitude of 25-30 ° and fucked near the zone of the calm somewhere in 6 degrees. The French believe that trade winds are "right winds" (Vents Alizes), very comfortable for movement under sails. Their speed is small, but constant (five to six meters per second, sometimes it reaches 15 m / s). However, the power of these air masses is so large that they form the trade-mounted flows. Bed in the regions with hot and these winds contribute to the development of deserts, such as Calahari, Namib and Atakam.

Are they constant?

Over the continents, the Passats face local winds, sometimes changing their speed and direction. For example, in the Indian Ocean, due to the special configuration of the shore of Southeast Asia and climatic characteristics, the trade winds turn into seasonal monsoons. As you know, they blow out of the cool sea in the summer in the direction of the heated sushi, and in the winter - on the contrary. However, the statement seem to the trade winds is the winds of tropical latitudes, not quite right. In the Atlantic, for example, in the northern hemisphere they blow in winter and spring in the range of 5-27 ° S.Sh., and in the summer and in the fall 10-30 ° S.Sh. This strange phenomenon in the XVIII century gave a scientific explanation of John Gadley, a British astronomer. The skylessness band is not worth the equator, but moving after the sun. Thus, by date, when our luminais is standing in the zenith over the tropical of cancer, the trade winds are shifted to the north, and in the winter - to the south. Easternatures are constant wind and for strength. The Passat of the Southern Hemisphere is more powerful. He almost does not meet the barriers in the form of sushi. There, it forms the so-called "roaring" fortress latitudes.

Passats and tropical cyclones

To understand the mechanics of the formation of typhoons, it is necessary to understand that two permanent winds blow in each hemisphere of the Earth. All that we described above relates to the so-called Lower Passatam. But the air, as is known, is cooled when climbing to height (on average one degree every hundred years of lifting). Warm masses lighter and rushing upwards. Cold air tends to descend down. Thus, opposite trade winds arise in the upper layers of the atmosphere. In the northern hemisphere from the south-west, and lower from the equator - from the North-West. Inside the trade winds sometimes changes the steady direction of two layers. There is a zigzag twisting of warm, saturated moisture and cold mass of air. In some cases, tropical cyclones are gaining a hurricane strength. The same vector of directions inherent in the trade winds carries them to the West, where they collapse their destructive power on coastal areas.

Causes of air movement

The atmospheric air is in constant and continuous motion. Air movement can be ascending at which it rises up and downward - the air is lowered down. There is another movement - horizontal.

Definition 1.

Horizontal Air movement got a name wind.

Air movement depends on atmospheric pressure and temperature. In addition to these main reasons, the effect of friction on the surface of the Earth has an influence, meeting with any obstacle, rejecting the power of Coriolis. In the northern hemisphere, in connection with this Coriolis force, the air flows are deviating Right, in the southern hemisphere - Left.

Note 1.

Air flow It always moves from the high pressure area into the low pressure region.

Any wind has its own direction, strength and speed, which depends on pressure. If the pressure difference of two neighboring territories is large - the wind speed will increase. On average, the surface of the Earth has a multi-year wind speed reaches $ 4-9 $ M / s, sometimes there is $ 15 $ m / s. Storm winds blow at a speed, up to $ 30 $ m / s, with gusts up to $ 60 $ m / s. Tropical hurricanes reach $ 65 m / s reach, and in the gusts reach - $ 120 $ m / s.

In addition to meters per second, kilometers per hour, the wind speed is measured in the scores on the scale Befort from $ 0-13 $. From Speed The wind depends on it forcewhich shows dynamic pressure Airflow on some surface. The wind force is measured in kilograms per square meter.

The side of the horizon with which the wind blows, determines its direction. For the designation of its direction, eight main rumbs are used, i.e. Four main side of the horizon and four intermediates. The wind direction will be associated with pressure and deflecting Coriolis. For its origin, the value and nature of the wind are very diverse.

For moderate latitudes are characteristic of the winds of Western directions, because the Western transfer of air masses dominates there is the North-Western, Western and South-Western winds. In the North and South Hemispheres, this area takes extensive spaces. The winds of the polar regions blow from poles on moderate latitudes, i.e. to the areas of low pressure. In the Arctic, the northeastern winds blow along the clockwise arrow, and in Antarctica, southeastern winds are blowing against a clockwise course. Antarctic winds are characterized by greater speed and stability. Passats dominate in tropical latitudes.

Permanent winds

Note 2.

Permanent winds During the year in one direction from areas high in the field of low atmospheric pressure. These include - trade winds, Western winds, Arctic and Antarctic winds.

Definition 2.

Passat - These are constant winds of tropical latitudes, which are from 30 parallels towards the equator.

The name of this constant wind was given by the Spaniards, calling it "Viento de Pasada", which means "wind favored by moving." The trade winds are blowing at a speed, $ 5-6 $ m / s, and covered the air layer with a height of $ 15-16 $ km. Powerful ocean currents are connected with them - in the Atlantic Ocean, the Antillest flow and Brazilian, in the Pacific Ocean, Mindanao and the East Australian, Mozambique in the Indian Ocean. The region of the planet, blowed by the trade winds, has a peculiar climate - mainly the weather with a small amount of precipitation prevails. On land, this climate contributes to the formation of deserts and semi-deserts. In the northern hemisphere, the Passats are directed from the northeast, and in the southern hemisphere from the south-east to the equator.

Definition 3.

Western winds - These are constant winds of moderate latitudes, which are from the tropics on the 60s parallels.

The tropical air normalizes the temperature of moderate latitudes and makes it favorable for people's life. Moderate latitudes are the meeting place for warm and cold air masses. Warm air masses go from the tropics, and the cold comes from the polar regions. As a result of their contact form cyclones and anticyclones. The moderate belt itself is the area of \u200b\u200breduced pressure, so quite strong air masses come here. The western transfer of air masses is dominated here, half of them is formed in the north, and the other half is formed in the east and they all blow in one west direction. In general, the Western winds soften the weather - summer will be cool with a possible rain. Winter will be accompanied by thaws and strong snowfall. The North Wind will hit the cold, and with the southern wind will come warm. The eastern wind is less predictable - it can be both warm and cold, but there will be no large amount of precipitation in the summer or in the winter.

The polar type of climate forms two belts - arctic and Antarctic. Polar air masses will be permanent for this area of \u200b\u200bthe planet during the year. Arctic The polar wind is strong enough blowing on moderate latitudes along the clockwise arrow. It blows only in the southern direction and comes to the North Coast of Eurasia, North America. Together with this wind comes a sharp cooling. In the southern hemisphere, the polar wind is called Antarctic And only blows north against the course of the clockwise, moving towards moderate latitudes. The wind is very strong and cold.

Seasonal winds

Definition 4.

Seasonal The periodic winds are called, the direction of which varies half a year.

One of these winds are Mussons.

Definition 5.

Mussons - These are winds, changing their direction depending on the time of year.

Monsions are steady and covered huge areas. Their stability is associated with the distribution of atmospheric pressure during each season. The reason for the emergence of monsoons is different heating of sushi and water for a year, which means that there is a winter musson and summer. When the monsoon changes in spring and autumn, the stability of the wind mode is broken. Winter Musson Blowing from sushi to the sea, because during this period the mainland is cold, it means that the pressure above it will be high. In the summer, when dry heats up, the pressure becomes lower and the wet air from the ocean moves to the land - this Summer Musson. Dry cloudless winter weather changes in summer on rainy weather.

In different areas of the planet, the nature of the circulation of the atmosphere will be different. This determines the differences in the causes and nature of monsoon, therefore distinguish vneipic and tropical monsoons.

Vneopic Monsions are characteristic of moderate and polar latitudes. The result of their formation is a different pressure over land and sea for the season. As a rule, the veneropic monsins are formed in the Far East, Northeast China, Korea.

Monsions of tropical lards Defended by the fact that by the season of the year the North and South Hemispheres are heated and cooled differently. This leads to the fact that for the season of the year, the atmospheric pressure zone relative to the equator is shifted to the hemisphere, in which this time summer and the trade winds penetrate there. Passatove mode is replaced for the tropics of the winter monsoon. Such a change contributes to the West air flow in the low atmospheric pressure area at the equator, which shifts along with other zones. Tropical monsoons are resistant in the northern part of the Indian Ocean.

On the coasts of the seas and oceans, winds are formed, called name breeze. These winds have local importance and in the daytime blowing from the sea to the land, and at night they change their direction to the opposite - from sushi to the sea. As a result, distinguished day and night breeze. Drying during the daytime heats up faster than water and low atmospheric pressure is installed above it. Above water in the same period, the pressure will be higher, because it heats up significantly slower. As a result, the air from the sea begins to move to the land. At night, the reduced pressure is celebrated above the water, because she did not have time to cool, and the air will move from sushi to the sea.

Shore breeze shortly until noon will be replaced by the sea, and in the evening the sea breeze will become coast. Breeze can form on the shores of large lakes, large reservoirs, rivers. From the coastline, they penetrate the land on tens of kilometers and especially frequent in the summer with clear and quiet weather.

The total circulation of the atmosphere includes passat, western winds moderate Shi-mouth, eastern (Stock) Winds polar regions, as well as mussons.

The wind occurs due to the difference in atmospheric pressure. Since there are relatively constant belts on Earth, they depend on them lord-winds (Also they are called constant, predominant, dominant or preferential).

Moving air masses moving with resistant winds in a certain order. They create a complex air flow system across the globe. It is called the total circulation of the atmosphere (from the Latin word circulation - rotation).

There are relatively sustainable dominant winds between the beans of the atmospheric pressure of the Earth, or the winds of the prevailing directions.

Passat

Among the constant winds are famous - passat.

Passat - Sustainable winds for the year, directed from tropical latitudes to equatorial and having the same Eastern direction.

Passage are formed in a hot heat belt and blowing from an increase in pressure in the area of \u200b\u200b30 ° C. sh. and 30 ° sh. towards the equator - areas with lower pressure (Fig. 31). If the Earth did not rotate, then the winds in the northern hemisphere would do exactly from the north to south. But due to the rotation of the Earth, the winds deviate from the direction of their own movement: in the northern hemisphere - to the right, and in the southern hemisphere - to the left. This phenomenon is called the effect of Coriolis - by the name of the French scientist, and he manifests itself in relation to not only winds, but also, for example, sea currents and the relevant coast of large rivers (in the northern hemisphere - right, in the southern - left).

The Passat of the Northern Hemisphere is the northeast wind, and the Passat of the Southern Semi-Sharia - Southeast.

The trade winds blow with a rather high speed, approximately 5-6 m / s, and weaken, taking out near the equator, - the zone of calm is formed there. The trade winds over the ocean differ in particular constant. This was noted the navigators of the past, which went to the sailing ships and were very dependent on the winds. It is believed that the title "Passat" happened from Spanish viente.dE.pasada.What does "wind favors moving" mean. Indeed, during the time of the sailing fleet, they help whether to travel from Europe to America.

Western winds of moderate latitudes

From the region of increased pressure of the hot belt, the winds blow not only in the hundred-Ron of the equator, but also in the opposite - in the direction of moderate latitudes, where the lower pressure belt is located. These winds, like trade winds, are rejected under the action of the Earth's rotation (Coriolis effect). In the northern hemisphere, they blow from the southwest, and in the southern hemisphere - from the North-West. Therefore, these winds call western winds of moderate latitudesor western transfer(Fig. 31).

With Western transfer of air masses, we are constantly faced in our latitudes in Eastern Europe. With Western winds, the sea air of moderate latitudes from the Atlantic comes to us. In the southern hemisphere of latitude, where the western winds are formed over the gigantic solid surface of the ocean and reach great speed, the name "roaring co-fat" were called. Material from site.

Eastern (Stock) The winds of the polar regions

Eastern (Stock) The winds of the polar regions Blowing towards the belts of low pressure temperate latitudes.

Mussons

Sustainable winds are often attributed to mussons. Mussos arise due to unequal heating of sushi and ocean in summer and zi my. Sushi area is much more in the northern hemisphere. Therefore, the monsoons are well expressed here on the eastern coasts of Eurasia and North America, where there are significant contrast in the warming of sushi and ocean in medium latitudes. Special variety is tropical monsoons that dominate in South and Southeast Asia.

Unlike other winds of prevailing directions, monsoons - seasonal winds. They change the direction twice a year. Summer Mus-Dream Dust from the ocean on land and brings moisture (rainy season), and the winter monsoon do with sushi on the ocean (dry season).

On this page, material on the themes:

  • Prevailing winds at the equator

  • What is monsoon? What directions are they blowing?

  • What are the names of constant winds

  • They helped to travel from Europe to America they call them

  • On the map Mark the Passats of Iussons Zap winds of moderate latitudes

Questions about this material:

Mussons (Franz. Mousson, from Arab. Massim - season)

sustainable seasonal air transfers from the earth's surface and at the bottom of the troposphere. Characterized by sharp changes in the direction from winter by summer and from summer to winter, manifested over the extensive areas of the Earth. In each of the seasons, one direction of the wind is noticeably dominated over others, and when changing the season is changing 120-180 °. M. cause a sharp change of weather (dry, stingy on wet, rainy or vice versa). For example, the summer (wet) south-west M. and Winter (Dry) Northeast M. Between M. There are transient relatively short periods with variable winds.

The greatest stability and speed of wind M. possess in some areas of the tropics (especially in Equatorial Africa, countries of South and Southeast Asia and in the southern hemisphere until the northern parts of Madagascar and Australia). In weaker form and in limited territories M. are also found in subtropical latitudes (in particular, on Y. Mediterranean Sea and in North Africa, in the field of the Gulf of Mexico, in V. Asia, in South America, on Y. Africa and Australia) . M. is also noted in some areas of medium and high latitudes (for example, in the Far East, on Y. Alaska, along the northern outskirts of Eurasia). In a number of places it is planned only a tendency to form M., for example, there is a seasonal change of prevailing wind directions, but the latter are characterized by less intra-seasonable stability.

Monso air flows, as well as all manifestations of the total circulation of the atmosphere, are due to the location and interaction of low and high atmospheric pressure (cyclones and anticyclones). The specificity is that at M. The mutual arrangement of these areas is preserved for a long time (for the whole season of the year), the violations of this location correspond to the interruptions of M. in those areas of the Earth, where cyclones and anticyclones are characterized by rapid movement and frequent shift, M. Not arise. The vertical power of monsoon flows in the tropics is 5-7 kM, in winter - 2-4 kM, above there is a total air transfer, peculiar to the relevant latitudes (oriental - in the tropics, Western - in higher latitudes).

The main cause of M. is the seasonal movement of atmospheric pressure and wind areas associated with changes in the flow of solar radiation and, as a result, with the differences in the thermal regime on the surface of the Earth. From January to July, the area of \u200b\u200blow atmospheric pressure near the equator and poles, as well as 2 zones of subtropical anticyclones in each hemisphere are shifted to S., and from July to January - to Y. Together with these planetary zones of atmospheric pressure, both the bounds of the winds are moved. Also having global sizes - the equatorial zone of Western winds, oriental transporters in the tropics (trade winds), the western winds of moderate latitudes. M. are observed in those places of land, which within one of the seasons are located inside one such zone, and in the opposite season of the year - inside the neighboring and where, in addition, the wind mode during the season is quite stable. T. about., Distribution of M. In general terms, the laws of geographic zonality are subordinated.

Another reason for the formation of M. - uneven heating (and cooling) of the sea and large sushi arrays. For example, over the territory of Asia in winter there is a tendency to greater repeatability of anticyclones, and in the summer - cyclones, as opposed to the adjacent waters of the oceans. Due to the presence of a huge mainland on C. Equatorial Western winds in the Indian Ocean basin in the summer penetrate far into South Asia, forming the summer south-west M. In winter, these winds are inferior to the Northeast Passat (winter monsoon). In the fiberglass latitudes, thanks to sustainable winter anticyclones and summer cyclones over Asia, M. are observed in the Far East - within the USSR (summer - South and Southeast, Winter - North and North-West) and on the northern outskirts of Eurasia (in the summer the prevalence northeast, winter - southern and southwestern winds).

LIT: Pedelborad P., Monspi, Per. from Franz., M., 1963; Chromas S. P., Monson as a geographical reality, "Izv. All-Union Geographical Obda ", 1950, vol. 82, c. 3; Its, monsoons in total atmospheric circulation, in the book: A. I. Wayers and modern problems of climatology, L., 1956; Drozdov O. A., Sorohan O. G., A brief overview of the works performed in Russia and the USSR on the characteristics of monsoons, "Tr. The main geophysical observatory ", 1961, c. 111.

S. P. Chromov.

Mussonny areas of the globe.


Great Soviet Encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .

Watch what is "monsoons" in other dictionaries:

    Misss, sustainable seasonal winds. In the summer, in the monsoon season, these winds usually blow from the sea to land and bring rain, and in the winter there is a sharp change of direction to the opposite, and these winds blow from sushi, carrying dry weather. Some regions ... ... Scientific and Technical Encyclopedic Dictionary

    Modern encyclopedia

    Mussons - (French Mousson, from the Arab Massim season), stable winds whose direction changes sharply to the opposite (or close to the opposite) 2 times a year. The mainly due to seasonal differences in the heating of the mainland. ... ... Illustrated Encyclopedic Dictionary

    - (Monsoons) Winds, periodically changing their direction depending on the time of year. M. is observed mainly in the tropical belt. M. are formed due to the difference in air pressure arising from uneven heating of sushi and ... ...

    - (FR.). Periodic winds on the Indian Ocean, which former six months on the one hand, and the other six with the opposite. A dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. Monsons winds of tropical countries, which is happening ... ... Dictionary of foreign words of the Russian language

    - (As suggesting from Arab Mausim), the winds of the year than the summer and winter from the opposite directions. Summer M. blowing thiesta and bring raw, rainy weather, in winter with sushi and bring clear weather to be clear. Classical Country M. India. ... ... Encyclopedia Brockhaus and Ephron

    Mussons - monsoons. See Morksai Vѣry ... Military encyclopedia

    - (Franz. Mousson, from Arab. Massim season), Sustainable winds, the direction of which changes dramatically to the opposite (or close to the opposite) 2 times a year. The mainly due to seasonal differences in the heating of the mainland. Winter ... ... encyclopedic Dictionary

    Air flows over significant regions of land, distinguished by the predominance of one direction of wind during the winter season and the opposite of it (or close to this) - during the summer. In accordance with the season, they often allocate winter and ... ... Geographic Encyclopedia

Which of us in childhood did not read the adventure books about distant wanderings, noble navigators and fearless pirates?


Using the words "Musson" and "Passat", we call these romantic paintings in memory: far from the tropical seas, uninhabited islands, covered with brown greens, ringing swords and white sails on the horizon.

Meanwhile, everything is more prosaic: monsoons and trade winds are well-known names that have a significant impact on the formation of the weather not only in tropical areas, but also on the entire planet.

Mussons

Monsons are called winds with a steady direction characteristic of a tropical belt and some seaside countries of the Far East. In the summer, the monsoon blows from the ocean in the direction of land, in the winter in the opposite direction. They form a kind of climate type called monsoon, a characteristic feature of which is a high level of air humidity in the summer.

It should not be thought that in areas where the monsoon dominates, there are no other winds. But winds of other directions appear from time to time and blow over short periods, while the monsoon is the prevailing wind, especially during the winter and summer. Autumn-spring periods are transitional, at this time the steady wind regime is broken.

Origin of monsoon

The emergence of monsoon is entirely connected with the annual cycles of atmospheric pressure distribution. In the summer, the sushus is heated stronger than the ocean, this heat is transmitted to the lower atmospheric layer. The heated air rushes upwards, and the zone of the atmosphere has been formed above the land.

The resulting lack of air is immediately filled with a colder air mass, located above the ocean stroke. It contains a large amount of moisture evaporated with aqueous mirror.

Moving in the direction of the sushi, the air from the sea takes this moisture and sheds to the surface of coastal areas. Therefore, in the summer, the monsonic climate turns out to be more wet than in winter.

With the onset of the winter period, the winds change their direction, since at this time the sushi surface is less actively warming up, and the air above does not turn out to be colder than above the sea, which explains the change of the direction of the monsoon at this time.

Geography Mussonov

The monsonic climate is most characteristic of Equatorial areas of Africa, the northern coast of Madagascar, many of the Southeast and South Asia states, as well as the equatorial part of the southern hemisphere, including the northern coast of Australia.

The influence of monsoons is experiencing the States of the Caribbean, the southern part of the Mediterranean and some other areas, but in a weaker form.

Passat

Passyat call winds stable in the tropical zone all year round due to the inertial power of the rotation of the Earth and the climatic features of the tropics.


In the northern hemisphere, the Passats blow from the northeast, and in South - from the south-east. The greatest stability of the trade winds is distinguished above the sea surface, while the land relief contributes certain changes in their direction.

The name "Passat" comes from the Spanish expression "Viento de Pasada" - the wind favored by movement. In the era of great geographical discoveries, when the queen of the seas was Spain, the trade winds served as a major factor that favors the movement of sailing vessels between the European mainland and the new light.

How are trade winds formed?

The equatorial zone of our planet is experiencing the strongest heating with sunbeams, so the air in the lower layer of the atmosphere always has a sufficiently high temperature. Because of this, in areas close to the equator, there is a stable upstream air flow.

Cold air masses from both subtropical belts - Northern and South are immediately rushed into place at the place of rising air. Thanks to the power of Coriolis - the inertial power of the rotation of the Earth - these air flows move not strictly in the southern and northern directions, but deviate, acquiring the southeast and northeastern direction.


The cold air rising cold air cools down and lowers down, but because of the outflow of air in the northern and southern moderate zones, he rushes there and is also experiencing the action of Coriolis forces. These winds, which are called the upper layers of the atmosphere, are called upper trade winds, or anti-therapy.

Geography Passatov

The trade winds are dominant winds along the entire equatorial belt, except for the coastal zone of the Indian Ocean, where they are transformed into monsoons due to the geographical features of the coastline.