The air masses around us are in continuous movement: up-down, horizontally. The movement of air horizontally we call the wind. Wind streams are formed in their specific laws. For their characteristics, indicators such as speed, strength and direction are used.
Winds of different climatic areas have their own features and features. Moderate latitudes of the northern and southern hemispheres blow on Western winds.
Permanent and variables
Wind direction causes high and low pressure areas. Air masses move from high pressure places to areas with low. The wind direction also depends on the action of the earth's rotation: in the northern hemisphere, the flows are adjusted to the right side, in the southern one in the left. Air flows can wear both permanent character and variable.
Western winds of moderate latitudes, trade winds, northeastern and southeasterns belong to the constant group. If the trade winds are called the winds of the tropics (30 o, S.Sh. - 30 o.Sh.), then Western winds prevail in moderate latitudes from 30 ° to 60 o in both hemispheres. In the northern hemisphere, these air flows are rejected to the right.
In addition to constant, there are variables or seasonal winds - breeze and monsoons, as well as local, characteristic only for a separate region.
The flow of western winds
The air, moving in a certain direction, has the ability to transfer huge masses of water in the ocean, creating strong currents - rivers among the oceans. The flows that have arisen under the influence of winds are called wind. In moderate latitudes, Western winds and the rotation of the Earth sends surface currents to the western banks of the mainland. In the northern hemisphere, they move in the direction of the clockwise, in South - against. In the southern hemisphere, the effect of wind and earthly rotation created a strong flow of Western winds along the coast of Antarctica. This is the most powerful oceanic flow that is reinforcing the entire globe from the west to the east in the area between 40 o and 50 on southern latitude. This course serves as a barrier separating the southern waters of the Atlantic, Indian and Pacific Oceans from the cold waters of Antarctica.
Wind and climate
Western winds affect the climate of the significant territory of the mainland of Eurasia, especially on that part of it, which is located in a temperate belt. With a dover of Vesta to the continent comes coolness among summer heat and thaw in winter. It is winds from the West in the Commonwealth with the warm ocean flow that the climate of the North-West Europe is much warmer than the same latitudes of North America. With the promotion of deep into the continent to the east, the influence of the Atlantic is reduced, but completely continental climate becomes only for the Ural ridge.
In the southern hemisphere, the buoy winds from the West do not interfere with any obstacles in the form of continents and mountains, they are free and free: Stormyat, fighting with ships, rushing east at high speed.
Who is friends with the wind
Unfortunate Vests are especially familiar with sailors on the routes of good hope - New Zealand - Cape Gorn. Picking a passing sailboat, they can dispersed it faster than a diesel vessel. Sailors are called Western winds brave in the northern hemisphere and roaring forty - in southern.
Many hassle delivered Western winds and first aviators. From America to Europe, they were allowed to fly, as they were passing. Pilots passed the route without problems. It was quite different about the flight from Europe to America. Of course, modern supersonic liners no wind is not a hindrance, but in the 20-30s of the nineteenth century he turned out to be a significant obstacle.
So the French pilots of Nenzheser and Collie in 1919 committed a historical flight across the Atlantic Ocean on the route Newfoundland - Azores - Iceland. But the same path in the opposite direction ended tragically. Pilots intended to repeat the famous path of Columbus through the air, only after 34 years, fragments of their aircraft on the US coast were found.
The tragedy is explained by the fact that strong winds have significantly detaining the aircraft, and it was not enough to the destination for the destination, it was not enough fuel.
The first wisdom of Gordienko's Soviet pilots and Kokkinaki in 1939 were defeated, successfully overcome the French route.
(XXXIII-XXXIV Cards)
Since there are validity centers, the wind distribution even on perennial average maps deviates from zonal.
On the maps XXXIII-XXXIV is presented by many years of data the prevailing wind directions from the earth's surface in January and in July. At the same time, the appearance of the arrows indicates the degree of repeatability of this direction in this place: each pen means 10% of repeatability. The presented climatological distribution of the wind gives, of course, a very simplified picture, since the number of points for which the wind directions are small. And, as clearly from the previous one, this climatological distribution is much easier than real distributions on certain days. But they still can be used for the initial orientation in the current circulation of the atmosphere.
The maps caused and the long-term average distribution of pressure at sea level so that the reader can compare it with the wind distribution. This pressure distribution is somewhat different in the details from the distribution on the XXIX-XXX cards.
On maps, first of all, the northeastern and southeastern winds in the tropics above the Atlantic, quiet and southern Indian oceans are well distinguishable. These are trade winds, the earth's surface is deviating from their main, eastern direction. The winds of the Western quarter of the horizon are striking in the forties and sixties in the southern hemisphere. This is the most stable part of the Western transfer in moderate latitudes. In the northern hemisphere, the predominance of winds of the Western Quarter is constantly expressed in moderate latitudes only over the oceans; Over the continents, the wind mode is more frequent and more difficult, although still the winds of the Western half of the horizon prevail over the eastern. Eastern winds of high latitudes are outlined on maps only in the outskirts of Antarctica; According to the latest data it would be possible to submit them more clearly. Finally, in the south, East and northern Asia and in some other areas there is a sharp change in the direction of the prevailing winds from January to July. These are areas of monsoon.
Learn more about air flows in different latitudes and regions of the Earth will be told in the subsequent presentation of this chapter.
In higher layers of the troposphere and lower stratosphere, the wind distribution is closer to the zonal, than the earth's surface; This follows from the above-mentioned changes in the height of the Baric field in the chapter six.
Map XXXIII. Prevailing wind directions in January.
Map XXXIV. Prevailing wind directions in July.
Each pen on the arrow means 10% of the repeatability of this prevailing direction.
Climatological winds of wind at altitudes are not given here; However, it is possible to judge the distribution of wind in the middle troposphere by barytic topography cards (XXXI-XXXII cards) above. The winds in the free atmosphere are blowing in almost an inaobram or in the inventory of absolute baric topography, leaving low pressure in the northern hemisphere on the left and in the southern right.
For most of the territory, moderately continental, on the Black Sea coast south of Tuapse - subtropical. The ridges of the Grand Caucasus closes the coast of the Black Sea from the cold winds, which causes the features of the subtropical climate. The territory of the edge of the Kuban River is divided into two sharply different parts: the northern plain and southern mountain. The flat zone is the bonus lowland - takes two thirds of the territory and is the economically most developed part. The southern zone is formed by the ridges of the Ranges of the Western Caucasus, to which the band is adjacent and the narrow tape of the Black Sea coast. Krasnodar region is located on one geographic parallel with Northern Italy and South France. Located on the border of moderate and subtropical latitudes, at the junction of the plains and the mountains, the land is distinguished by a variety and impermanence of weather conditions. Sophisticated physico-geographical conditions, a variety of landscapes, the proximity of the seas make changes to the total transfer of air masses and determine the large variety of climate in the territory.
The climate is significantly changing from the west to the east.
The average temperature of January minus 2.6 ° C (on the plain - minus 3-5 ° C, on the coast + 5 ° C, in the mountains -8 ° C). The average temperature of July plus 22.6 ° C (on the plain - + 22 ° C, on the Black Sea coast + 25 ° C; in the mountains + 13 ° C). An annual amount of falling precipitation ranges from 350 mm on the Taman Peninsula and 500 mm on the Right Bank of Kuban up to 2500 mm and above on the southwest slopes of the Caucasian Range. Each spring the edge flood floods. In general, the edge is characterized by hot summer and soft winter.
In the edge, average annual temperatures are lowered with a height. For winter, unstable weather is characterized with alternating short frost and warm periods, lack of frosting soil and stable snow cover. The preciputes fall in the form of snow, rain and wet snow. For the winter, the amount of precipitation 100 is 180 mm, on the Black Sea coast 144 - 270 mm. The distribution of precipitation through the territory is extremely uneven, especially in mountainous areas, where the height and exposition of the slopes affect the size of the precipitation. The amount of precipitation for the year increases through the territory in the direction from the north to the south and the average is at most of the plain areas of 500 - 600 mm. In the foothills and adjacent to them, it increases to 700-800 mm, and in the mountains up to 800-2000 mm. Maximum precipitation on the flat part falls for the summer, and on the coast - on the cold part of the year.
The warm half year is characterized mainly by the Western-oriental transfer of air masses along the periphery of the high pressure band (Azov origin), which causes steadily hot weather. Often, such circulation is disturbed by the breakthroughs of Western and southern cyclones causing strong rave precipitation with thunderstorms, and sometimes intense illness.
In the south of the region, on the Black Sea coast, local (private) cyclones are periodically formed, which also cause severe livnery here.
Insufficient precipitation in the plain areas determine the dryness of air and soil, which causes greater repeatability of drought and Sukhovyev. In the mountains, dry phenomena are absent, on the coast of drought are rarely and weak intensity
Most of the summer is moderately hot, the hottest days comes to July-August. The maximum temperature exceeds plus 35 - 39 ° C, the number of days with a maximum temperature above 30 ° C for the summer is about 30 to 65 days. The highest sum of air temperature over a period of temperatures above 10 ° accumulates on the Black Sea coast - up to 4000 - 4200 °. On the flat part of the territory it is 3400 - 3600 °, in the foothills of 3000 - 3400 °. With an increase in the height of the terrain, the amount of heat decreases. In the mountains at an altitude of 2000 m, the sum of active temperatures is 1000 °, which does not ensure the cultivation of crops even with the shortest vegetation period.
The duration of the warm period (period with air temperature is higher than 0 ° C) for the most part of the territory is 9 - 10 months, and in the Black Sea coast of the steady transition after 0 ° does not happen, i.e. the decrease in air temperature to negative values \u200b\u200bis observed in the cold period Only within a few days.
The smuggous period in most areas lasts 180--200 days, on the Black Sea coast - 220--260.
The uneven distribution of precipitation, sharp temperature fluctuations, the destructive effect of Sukhovyev and drought cause the need to strict adherence to the scientifically based agriculture system in the cultivation of crops, an increase in forest belt and other hydro-accumulating and anti-erosion measures. Nevertheless, the climate in the region is one of the most favorable in Russia for living and human activity. Krasnodar Territory is the warmest region of Russia, the average duration of time, when in the bright time of the day in the territory there is a sunny weather, it is 2,300 hours a year. The amount of total solar radiation coming into this territory varies from 115 kcal / sq. Cm in the north of the edge to 120 kcal / sq. Cm in the south.
If we talk about specific areas of the Krasnodar Territory, then on the Kuban-Priazovskaya lowland, the climate is moderately continental with insufficient moisture and the predominance of warm and solar weather. The average annual temperature is + 11 ° C. Hot summer. July has a middle monthly heat treatment + 23 ° C (Krasnodar). The average temperature of January is about 4 ° C, but will not be unexpected and frost to - 20 ° C. The plain territories are open from the north and are available to the action of the Arctic air masses. Northeastern winds, especially at the beginning of the winter, with a small or no missing snow cover, regularly cause damage to winter cultures. The sediments are usually in the form of rains (even in winter). The total amount of precipitation is sufficient, but they are unevenly distributed during the year: in the summer, drought are frequent with the predominance of oriental winds. In the northern and northeastern regions of the region (Yeysky - Kushchevsky districts) Cold Winter and hot summer (with a temperature of up to + 35 ° C); autumn is shorter than in other regions of the region; For winter and spring, dust storms, brought to the eastern northeastern winds, are common; These storms demolish the upper fertile layer of the soil. In the east of the region - in Tikhoretsky and Caucasian districts - unstable winter with sharp changes of negative and positive temperatures; Early but cold in the first half of spring; roast, with rains, thunderstorms and winds in the first half and arid in the second half, summer; Dry and warm autumn. In the central regions of the region - Krasnodar, Ust-Labinsk, Crimean, Dinsky districts - most often blowing the northeast wind, which in the summer he dries the soil; And the Western and South-Western winds are raining (in winter, in winter, in winter); During the rain in December-January, thunderstorms are possible.
At the Taman Peninsula, the climate is steppe, arid with dry hot summer (average temperature + 24 ° C) and soft and damp in winter. Preferential winds, often great strength, have the northeastern direction. For the year up to 350 mm precipitation on Taman and up to 400 mm in Temryuk. Maximum precipitation falls on autumn and winter. For summer, infrequent rainy rains are characteristic.
Climate of footnight without sharp fluctuations in monthly and daily temperatures. The climate here depends on the height of the terrain: at a lower western part, the average annual temperatures rise to + 11 ° C, in a higher eastern part - are close to + 8 ° C. In each of the valleys, its unique microclimate. Within a long summer, the duration of 4-5 months the average temperature gradually increases from 14 ° in May to 22 ° in August. Droughts in the summer are rare and short. But there is a hail that destroys crops. Autumn and spring warm, with rare rains. Winter is soft (the average monthly temperature of January in the central regions minus 1.6 ° C) and short (2 - 3 months). In the winter months, snow drops, but quickly melts: on the southern slopes of the hills and mountains during the day.
The climate of the mountain part depends on the height: the higher, the colder. When lifting every 100 meters, it becomes colder about half generators. The average annual temperature is approximately + 4 °. In October - November in the mountains already lies snow. Winter is long, snowy and windless. In the mountains, Vividly expressed a change of vertical climatic belts: in the foothills, the warm climate, in the middle of the mountains - the cool (summer is short, and the winter is long and multispere), and in the alpine part, the climate is moderately cold. At an altitude of more than 3,500 meters lie eternal snow.
Now let's talk about the climate of the Krasnodar coast of the Black Sea. Here, the high Caucasian mountains detain cold air flows running from the north. The sea has a softening effect on the climate of coastal areas, which is determined by the movement of air masses (cyclones and anticyclones) over the sea, the nature of the shores and the terrain of sushi. The climate on the coast is soft, warm.
Two anticyclones have a predominant effect on the climate of the coast: Siberian (Winter) and Azores (summer). They bring sustainable clear weather in winter and warm dry summer. Cyclones from the Atlantic and Mediterranean Sea brought rainy unstable weather. Siberian (or Asian) Anticyclone creates a stable northeast winds over the Black Sea, famous Black Sea Nord-osce. Especially strong wind is observed in Novorossiysk and adjacent areas - the so-called boron. Under the bore, the wind speed usually reaches 40 m / s, and with gusts - up to 80 m / s. If we consider that the wind speed over 34 m / s is already considered hurricane, then you can approximate the power of the boras. And if you take into account yet and quick fluctuations in wind speed (from 10 to 60 m / s for a minute), it will not be a surprise to take the fact that there were cases when the gusts of the wind overturned railway cars. There is a boron as a rule, in winter. At this time, the air temperature may fall to minus 20 ° C with heavy snowfall. Bora is available in Novorossiysk 40-50 days a year, although not always, fortunately, reaches a crushing force. The impact of cyclones on the coast weather occurs as follows: Initially, strong, but short southern winds are blowing; The temperature grows and from time to time it rains. Then the southern winds are replaced by strong Western with precipitation. Finally, they begin to blow unstable, sometimes strong, northwestern and northern winds with clear weather and the drop in air temperature.
The landline land relief strongly affects the distribution of precipitation: in the Krasnodar coast, cyclones meet on their mountain path and precipitation occurs. For comparison: the plain Crimean coast, located on the same path of cyclonic air, remains without rains.
For the sea coast of the Krasnodar Territory, natural breets that bring a pleasant coolness and are felt even at a distance of 20-30 km from the coast: during the day they blow from the sea to land, and at night - from sushi to the sea. Also on the mountain coast, the so-called Fenoi develops: warm, dry winds that breathe from the mountains. In Sochi, for example, at FIU, the relative humidity of the air drops to 10-12%. If usually, in the evening there is a cooler and fresh, then at Feno from the mountains pulls heat and there is a lack of moisture. Usually the action of Finov is noticeably in spring, less often in the fall and winter (in October - December). The duration of their 1-2 days, rarely week.
Sometimes tornadoes are rushed over the sea, most often in the fall. Usually, the tornadoes appear over the sea at a thunderstorm when black clouds crawl across the sky. If the tornado goes to the shore, then. As a rule, it rises up the valley of the river flowing into the sea, and, having passed a few kilometers, collapsed. Entertained enormous mass of water fall on Earth and the river is spread.
Winds North - Eastern Black Sea
The northeastern part of the Black (BCR) of the sea is one of the energy-in-law zones of the Black Sea basin and in relation to other areas of the Black Sea is characterized by the most intensive storm activity, which must be taken into account in the construction of offshore and coastal WES, high wind speeds are celebrated in almost all parts of the coast And in all seasons of the year. Nevertheless, zones of high wind activity are distinguished, where the mid-one-year wind speed values \u200b\u200bexceed 5 m / s (capes, Taman, Anapa). The strongest winds are observed above the open part of the sea, as well as in the areas of Novorossiysk ("Bora") and in the Kerch Strait.
The wind speed has a well-pronounced annual move with a maximum in the cold period and in a minimum in warm. In winter, in the coastal zone, the HPhRhm range of the values \u200b\u200bof the average wind speed varies from 2.7-2.8 m / s per skirt up to 6-7 m / s in the areas of the Kerch Strait. Summer wind speed decreases to 1.9-2.4 m / s and 3.3-5.3 m / s, respectively. The wind speed in the area of \u200b\u200beach station depends not only on the time of year, but also from the coastal relief. Therefore, at such open stations like Taman and Anapa in the most windy years, the average monthly wind speeds in the winter reach 9-13 m / s, and in Novorossiysk (Cemesky Bay) 15 m / s, i.e. In the cold period, wind strength winds can act throughout the month. Maximum average wind speeds are most often observed in November-March. The maximum wind speeds obtained under urgent observations in the areas of Anapa and Novorossiysk reached 35-40 m / s. The average number of days with a strong wind (? 15 m / s) varies from 22-25 days from the Eastern coast of Crimea to 55 days in the Novorossiysk area. Along with the average and maximum wind speed values, practical interest are information about the repeatability of various gradations of speed. Wind speed recipiency curves (Fig. 1), calculated on the rows of average daily values \u200b\u200bwith intervals in 1 m / s, show that the greatest repeatability of weak winds (0-5 m / s) is marked on the eastern coast of Crimea (Yalta - 90%, Feodosia - 78%) and in the southern part of the Kerch Strait (cherished - 71%). Much less often weak winds are observed in the northern part of the Kerch Strait (54%), in the Caucasian coast (54%) and in the open part of the shelf (46-52%), where the repetition of the strong (\u003e 10) winds are maximum. For example, in the central part of the northeastern shelf at Anapa, it reaches 16% of the total number of observations.
Fig. one
The winds of the hurricane force whose speed exceeds 25 m / s, are observed on most stations, but have a small repeatability (0.08-0.09%). At the stations of the Kerch Peninsula - this is 2-5 days, in Anapa to 16 days., And in Novorossiysk, the repeatability of such winds is 1.5%. This is over 50 days. For observation periods. The relative distribution of wind repeatability in different parts of the coast can be estimated in fig. 1A, and a visual idea of \u200b\u200bthe magnitudes of the repeatability and speeds of strong winds in the region under study gives histograms. 5 B. Seasonal changes in the repeatability of strong winds (? 10 m / s) and cases of lack of wind (cali) are shown in Fig. 2.
Fig. 2.
From October to March, the repeatability of cases of strong winds varies from 2.5-5.0% in the districts of the Southern and Eastern Coast of Crimea (Yalta, Alushta, Feodosia) to 16-21% at the Caucasian coast and 24-26% in the open part of the North Eastern shelf (Fig. 2a). In the period from May to August, the repeatability of the storms decreases to 3-5% of Anapa and the capes and to 0.3-0.5% in the Skk area. In the summer, on the coast, the BLACHM prevails, low-voltage weather prevails, however, the cases of 92 full calm in the open sections of the coast are very rare. For example, in the central part of the shelf and the Caucasian coast, the repeatability of the calm throughout the year is less than 2%, in the area of \u200b\u200bthe Kerch Strait - 3-9%. Only in the Feodosian bay, the repeatability of calm in the spring-summer period reaches 9-12%, and even 15-17% in the cement bay (Fig. 2B). The relatively small repeatability of the calm is associated with the breeze circulation in the coastal zone, as a result of which the winds blow from a cooler water surface to a strongly heated bank, and at night - from the shore. Brist has been observed from April to October, but their greatest repeatability is marked in July and August, when brize situations can be held most of the month. The main directions of the wind over the Black Sea are determined by the distribution of atmospheric pressure in different seasons of the year. In the cold period, under the influence of cyclonic areas over the Mediterranean and Black Seas, the transfer of continental polar air is predomined, accompanied by the northeast, northern and northwestern winds. In summer, the prevailing influence of the Azor maximum causes Western, southwestern and southern winds. The features of the wind regimen are associated not only with the generalization of synoptic processes, but with the relief, orientation and configuration of the coast of individual regions of the coastal zone, so the HPCH has its own characteristics. In fig. 3 are the average annual roses of wind repeatability in the directions on which the contours of the total repeatability lines are depicted for all gradations and lines corresponding to the wind repeatability< 10 м/с.
Shaded areas among them correspond to the values \u200b\u200bof the repeatability of storm winds (? 10 m / s). Rose winds "Sea" is calculated for the central part of the northeast shelf. The legend of its hatching shows the repeatability of different gradations of wind speed (from 1 to 30 m / s) in directions. In the area of \u200b\u200bthe Feodosi Bay, Western (21%) and North-Western (18%) winds have the greatest repeatability. In the skirt zone, besides these winds, the Eastern (21%) and the southern (13%) winds have increased repeatability. In the north of the Caucasian coast, the eastern, northeastern (25%), southern (23%) and southeast (17%) winds are more often observed.
Figure 3.
Strong winds
Throughout the coast, the SCChm strong winds are observed annually and in all seasons. Throughout the year, the storm winds of the northeastern and eastern directions are dominated. Their average annual repeatability in the sea is 4.5% for northeastern and 1.9% for oriental winds. In fig. 9 are represented by roses of repeatability of the storm wind 10-30 m / s on the shelf (sea) and coastal stations. Almost all roses of the winds of the northeastern part show the predominant repeatability of the storm winds of the northern half of the horizon (up to 2.8-3.8%) and the eastern (1.3%), less often - southern Rumbes.
Despite the fact that the northern, northeastern and eastern storm (\u003e 10) winds are mainly observed by the coast, their strength (up to 35-40 m / s) and relatively large repeatability (in the amount of up to 7%) can adversely affect On hydrotechnical and wind power facilities, destroy the blades of engines, break the masts, contribute to the development of strong wind flows and unrest, which, in turn, must be taken into account when booking by the foundations or anchorage systems of offshore VES.
The most dangerous directions of wind for the UNFCM are the South-West (UZ), South (U) and Southeastern (SJT). The average annual repeatability of these winds is small: Yow - 0.14%, Yu - 0.08%, UZ - 0.16%. In February, their repeatability increases to: Yow - 0.82%, Yu - 0.28%, UZ - 0.37%. To estimate the seasonal variability of winds, not distorted by the conditions of the coastal zone, the repeatability of storm winds (10-30 m / s) in directions at various months of the year was calculated on the basis of the aforementioned digital array of atmospheric pressure and the calculated wind over the sea for the center of the northeastern part of the Black Sea (Fig. 10). The season with the greatest repeatability of strong winds (\u003e 10 m / s) lasts from November to March with a maximum in January-February (up to 10.5%). Less frequently, strong winds are celebrated in the summer months. In the winter months, the repeatability of the northeastern storms reaches 7-10%, in the summer decreases to 0.6-0.8%.
Despite the relatively small repeatability of the strong winds of the southern quarter, and on the shelf, it in sum reaches 3%, during periods of rare, but strong storm winds of the south-western and southern directions, the rates of hurricane strength, which at maximum accelerations cause extreme excitement. The decisive factor of wind conditions over the Black Sea is the structure of the baric field. Strengthening wind speed over the sea and the coast is due to the most often cyclonic activity. In the Black Sea, and, in particular, in the northeast part of it, the autumn cyclones are allocated with their destructive consequences, which happen once every 7-10 years and differ from ordinary cyclones.
Their peculiarity is that they pass over the pool during the autumn cooling period (most often in November), when a relatively high temperature of the water remains some time.
Rare, but strong storms are distinguished by hurricane speeds. The repeatability of such storms is small, and the destructive power is maximum. It is necessary to take into account when building large windarons, materials of increased stability should be used, and the installers themselves must withstand wind speeds up to 35 m / s (Fig. 1).
Moving air above the surface of the earth in the horizontal direction is called Wind. The wind always blows from the high pressure area into the low area.
Wind characterized by speed, strength and direction.
Wind speed and power
Wind speed It is measured in meters per second or in points (one score is approximately 2 m / s). The speed depends on the Baric gradient: the greater the baric gradient, the higher the wind speed.
The strength of the wind depends on the speed (Table 1). The greater the difference between neighboring grounds of the earth's surface, the stronger the wind.
Table 1. Wind power in the earth's surface on the Bafort scale (at a standard height of 10 m above the open level surface)|
Balves Beaufort |
Verbal definition of wind power |
Wind speed, m / s |
Wind effect |
|
|
Calm. Smoke rises vertically |
Mirror smooth sea |
|||
|
The direction of the wind is noticeable but the following smoke, but not on the fluger |
Ripples, foam on the ridges |
|||
|
The wind movement is felt on his face, leave the leaves, drives in motion. |
Short waves, ridges do not overturn and seem to be vitreous |
|||
|
Leaves and thin branches of trees all the time pegs, wind waves top flags |
Short, well-pronounced waves. Combs, tilting, form a glass foam, occasionally small white lambs are formed |
|||
|
Moderate |
The wind raises dust and papers, drives thin branches of trees |
Waves elongated, white whiskers are visible in many places |
||
|
Thin trunks of trees are swinging, waves appear on the water with ridges |
Well developed in length, but not very large waves, white lambs are visible everywhere (in some cases splashes are formed) |
|||
|
Thick branches of trees are swinging, the telegraph wires are buzzing |
Large waves begin to form. White foam ridges occupy significant fasteners (splashes likely) |
|||
|
Trees trunks are swinging, it's hard to go against the wind |
Waves are prayer, the ridges are broken, foam lies with strips in the wind |
|||
|
Very strong |
The wind breaks the bitch of the trees, go against the wind is very difficult |
Moderately high long waves. At the edges of the ridges begin to take the splashes. Foam strips fall rows in the direction of wind |
||
|
Minor damage; The wind breaks down the smoke caps and tiles |
High waves. Foam is widely dense stripes falling around the wind. Combs of the waves begin to overturn and crumble into splashes that worsen visibility |
|
Heavy storm |
Significant destruction of buildings, trees break down with the root. There is rare on land |
Very high waves with long-breeding down crests. The resulting foam is blown by the wind by large flakes in the form of thick white stripes. The surface of the sea is white from foam. A strong crash of waves is like shocks. Visibility bad |
||
|
Cruel storm |
Large destruction at a significant space. On land is very rare |
Exceptionally high waves. Courts of small and medium sized at times are hidden from the view. The sea is all covered with long white foam flakes located in the wind. The edges of the waves are blown away in a foam. Visibility bad |
||
|
32.7 or more |
The air is filled with foam and splashes. The sea is all covered with foam stripes. Very bad appearance |
Scale Beaufort. - The conditional scale for visual assessment of the strength (speed) of the wind in points in its action on ground items or by exciting on the sea. It was developed by the English admiral F. Beaufort in 1806 and first applied only to them. In 1874, the Permanent Committee of the First Meteorological Congress accepted the Beaufort Scale for use in international synoptic practice. In subsequent years, the scale varied and specified. Beaufort scale is widely used in marine navigation.
Direction of the wind
Direction of the wind Determined on the side of the horizon with which it blows, for example, the wind blowing from the south is south. The direction of the wind depends on the distribution of pressure and from the deflecting effect of the Earth's rotation.
On the climate map, dominant winds are shown by arrows (Fig. 1). Winds observed in the earth's surface are very diverse.
You already know that the surface of the sushi and water is heated in different ways. On a summer day, the surface of the sushi is stronger. From heating air over land expands and becomes easier. Over the reservoir at this time, the air is colder and, therefore, harder. If the reservoir is relatively large, in a quiet hot summer day on the shore you can feel a light breeze blowing from water, above which is higher than above the land. Such a light breeze is called daily Breeze (from Franz. Brise is a light wind) (Fig. 2, a). Night breeze (Fig. 2, b), on the contrary, blows from sushi, as the water is cooled much slower and the air over it is warmer. Brist can occur both on the edge of the forest. Briz scheme is presented in Fig. 3.
Fig. 1. The distribution scheme of the dominant winds on the globe
Local winds can occur not only on the coast, but also in the mountains.
Foney - Warm and dry wind blowing from the mountains in the valley.
Bora - Gusty, cold and strong wind appearing when cold air turns through low ridges to the warm sea.
Monsoon
If the Breeze changes the direction twice a day - day and night, then seasonal winds - Mussons - Change your direction twice a year (Fig. 4). Summer, the dryer is quickly heated, and the air pressure above its surface. At this time, the cooler air begins to move to the land. In winter, everything is the opposite, so the monsoon blows from sushi to the sea. With the change of winter monsoon on the summer, a change of dry cloudless weather on rainy.
The action of monsoon is strongly manifested in the eastern parts of the continents, where the huge spaces of the oceans are adjacent to them, so such winds often bring abundant precipitation on the mainland.
The uneasy nature of the circulation of the atmosphere in different parts of the globe determines differences in the causes and nature of monsoon. As a result, blurred and tropical monsimes distinguish.
Fig. 2. Breeze: a - daily; B - Night
Fig. 3. Briz scheme: a day; B - Night
Fig. 4. Monspi: A - in summer; b - winter
Vneopic Monsons - monsoons of moderate and polar latitudes. They are formed as a result of seasonal pressure fluctuations over the sea and land. The most typical zone of their distribution is the Far East, Northeast China, Korea, to a lesser extent - Japan and the northeastern coast of Eurasia.
Tropical Monsoons - Tropical latitudes monsions. They are due to seasonal differences in heating and cooling the northern and southern hemispheres. As a result, the pressure zone is shifted to seasons relative to the equator to the hemisphere, in which this time is summer. Tropical monsions are most typical and stable in the northern part of the Indian Ocean basin. This consistently facilitates the seasonal change of atmospheric pressure over the Asian mainland. The indigenous features of the climate of this region are associated with South Asian monscons.
The formation of tropical monsoons in other parts of the globe occurs less characteristic when one of them is more clearly expressed - winter or summer monsoon. Such monsoons are celebrated in tropical Africa, in Northern Australia and in the harevatory regions of South America.
Standing winds of the Earth - Passat and Western winds - depend on the position of atmospheric pressure belts. Since low pressure dominates in the equatorial belt, and close to 30 ° C. sh. and Yu. sh. - High, near the surface of the earth, throughout the year, winds blow from thirty latitudes to the equator. These are trade winds. Under the influence of the rotation of the Earth around the axis of the trade winds, they deviate in the northern hemisphere to the west and blow from the northeast to the southwest, and in the southern they are directed from the south-east to the North-West.
From high pressure belts (25-30 ° C. sh. And Yu. Sh.) The winds blow not only to the equator, but also in the side of the poles, since 65 ° C. sh. and Yu. sh. Low pressure prevails. However, due to the rotation of the Earth, they gradually deviate to the east and create air flows moving from the west to the East. Therefore, Western winds prevail in moderate latitudes.
The winds are a horizontal, sometimes impusty air movement. They depend on pressure, move where it is lower. Watching such a phenomenon, experts can make a rose of winds to a short and long time forward, to identify cycles and repetitions. They are subsequently focus on both navigators and
Western winds play an important role. They preferably move the tropical air into moderate latitudes. Due to this, the temperature in these territories is normalized, becomes acceptable to agriculture and a favorable person.
or where do winds come from
The atmosphere circulation is carried out due to the fact that the individual sections of the earth's surface are heated unevenly. This process begins at the equator. In the zone are located since the temperature difference is almost not observed, then the winds are actually absent. In the field of tropics, they blow in parallel to the equator, then closer to moderate latitudes, gradually change their direction.
The deviation from the equator naturally differs. In the northern hemisphere, trade winds are formed, which blow right. In southern - left. The directions of the Western winds closer to moderate latitudes are diverted in different directions as the northeastern.
This scheme may violate due to uneven heating of the aqueous and earth surfaces. When the sea and the coast are in contact, winds appear, which are out of the laws of the atmosphere circulation. These are large streams that change their direction depending on the season. They are called monscons and carry moisture on the continent.
Moderate latitudes
Western winds are almost the only air flows in moderate latitudes. This is a unique scheme that can boast of its ideality. The fact is that in moderate latitudes there are warm and cold air masses. The first appear in the tropics, the second - in the territories of the polar regions. Due to their contact, cyclones and anticyclones appear. They carry the air east from the West.
In moderate latitudes there is a reduced atmospheric pressure belt. Therefore, they come here, and they are pretty strong. Such winds have their own feature (like Passatov). They have an average deviation angle. It is due to the rotation of the planet (the effect of Coriolis).
The phenomenon is also called Western Transfer. The fact is that half of the air mass is formed in the north, the other part of them is in the east. But they all blow in one west direction. Their analogue in the southern hemisphere can be called trade winds, but there is a difference between them. It lies in the fact that parts of the planet are heated by the sun is not equally, therefore it is different.
Prevailing winds
They appear because there is a difference in atmospheric pressure, as well as due to the difference in temperatures. On the planet there are territories where both parameters are permanent and the same. Therefore, dominant winds appeared. They are also called predominant (or preferential). They are available almost all over the planet.
The prevailing northern or western winds move in a particular direction. They create circulation, or the rotation of the atmosphere.
In Eastern Europe and Asia, they carry sea air from the Atlantic, sometimes - precipitation. In the southern wind, it is formed above the surface of the water in the ocean, then rushes onto a dry speed.
Mussons
Speaking of what the Western wind can not be overlooked from the form of the monsoon. They are formed in the northern hemisphere on the eastern coasts. Western winds from moderate latitudes gradually begin to weaken, after the ocean is deployed. But on the replacement they come monsoon circulation. They are air flows that dramatically change their direction when changing winter in the summer, and vice versa. This is fundamentally different from dominant winds, which do not have a movement vector shift.
Misss are formed due to the difference in the heating of the sushi and the seas. Winter Northwest wind blows from the cold banks of Asia and Canada. His direction is a warm ocean that never freezes. There are summer, southeast wind. He originates in the ocean and moves to heated land. In fact, in winter, the West Wind, which appeared in the tropics, then moved to moderate latitudes, becomes monsoon. Part of the equatorial air is carried through natural streams almost up to the top of the poles.
The role of western winds
It is impossible to overestimate the role of the wind roses. And each of the dominant flows is distinguished by their contribution to the life of man and nature:
- Western winds, like trade winds, help vessels with sails (and a lot of them) cross the oceans or move where necessary.
- Air flows increase near coasts, therefore contribute to the formation of warm currents. Because of this, waters are met in all oceans. If this does not happen, it is formed stagnation. In fact, all the aqueous flora and fauna will perish, and after her - and humanity.
Finally, it should be noted that any Western wind takes direct participation in the global circulation of the atmosphere.
Conclusion
Thus, Western winds over the surface of the water in the entire ocean prevail over the water surface. But they move on land. Since they provide the world ocean with the flow and movement of water, to overestimate their importance and the role in nature is very difficult. You can call such winds to dominant. Without them there will be no circulation of the atmosphere and cycle of water.
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