Beaufort scale - wind force and sea conditions. Beaufort scale for visual assessment of wind force The Beaufort scale does not allow you to measure

Wind is the movement of air in a horizontal direction along the earth's surface. In which direction it blows depends on the distribution of pressure zones in the planet’s atmosphere. The article discusses issues related to wind speed and direction.

Perhaps, a rare occurrence in nature will be absolutely calm weather, since you can always feel that a light breeze is blowing. Since ancient times, humanity has been interested in the direction of air movement, so the so-called weather vane or anemone was invented. The device is a pointer that rotates freely on a vertical axis under the influence of wind. She points him in the direction. If you determine a point on the horizon from where the wind is blowing, then a line drawn between this point and the observer will show the direction of the air movement.

In order for an observer to convey information about the wind to other people, concepts such as north, south, east, west and various combinations thereof are used. Since the totality of all directions forms a circle, the verbal formulation is also duplicated by the corresponding value in degrees. For example, north wind means 0 o (the blue compass needle points exactly north).

The concept of a wind rose

Speaking about the direction and speed of movement of air masses, a few words should be said about the wind rose. It is a circle with lines showing how air flows move. The first mentions of this symbol were found in the books of the Latin philosopher Pliny the Elder.

The entire circle, reflecting the possible horizontal directions of forward air movement, on the wind rose is divided into 32 parts. The main ones are north (0 o or 360 o), south (180 o), east (90 o) and west (270 o). The resulting four lobes of the circle are further divided to form northwest (315 o), northeast (45 o), southwest (225 o) and southeast (135 o). The resulting 8 parts of the circle are again divided in half, which forms additional lines on the compass rose. Since the result is 32 lines, the angular distance between them turns out to be 11.25 o (360 o /32).

Note that a distinctive feature of the compass rose is the image of a fleur-de-lis located above the north icon (N).

Where does the wind blow from?

Horizontal movements of large air masses always occur from areas of high pressure to areas of lower air density. At the same time, you can answer the question of what wind speed is by studying the location of isobars on a geographic map, that is, wide lines within which the air pressure is constant. The speed and direction of movement of air masses is determined by two main factors:

• The wind always blows from areas where there is an anticyclone to areas covered by the cyclone. This can be understood if we remember that in the first case we are talking about zones of high pressure, and in the second case - low pressure.
• Wind speed is in direct proportion to the distance that separates two adjacent isobars. Indeed, the greater this distance, the weaker the pressure difference will be felt (in mathematics they say gradient), which means that the forward movement of air will be slower than in the case of small distances between isobars and large pressure gradients.

Factors affecting wind speed

One of them, and the most important one, has already been voiced above - this is the pressure gradient between neighboring air masses.

In addition, the average wind speed depends on the topography of the surface over which it blows. Any unevenness of this surface significantly inhibits the forward movement of air masses. For example, everyone who has been to the mountains at least once should have noticed that the winds at the foot are weak. The higher you climb the mountainside, the stronger the wind you feel.

For the same reason, winds blow stronger over the sea surface than over land. It is often eaten away by ravines and covered with forests, hills and mountain ranges. All these heterogeneities, which do not exist over the seas and oceans, slow down any gusts of wind.

High above the earth's surface (on the order of several kilometers) there are no obstacles to the horizontal movement of air, so the wind speed in the upper layers of the troposphere is high.

Another factor that is important to consider when talking about the speed of movement of air masses is the Coriolis force. It is generated due to the rotation of our planet, and since the atmosphere has inertial properties, any movement of air in it experiences deviation. Due to the fact that the Earth rotates from west to east around its own axis, the action of the Coriolis force leads to a deflection of the wind to the right in the northern hemisphere, and to the left in the southern hemisphere.

Interestingly, this Coriolis force effect, which is negligible in low latitudes (tropics), has a strong influence on the climate of these zones. The fact is that the slowdown in wind speed in the tropics and at the equator is compensated by increased updrafts. The latter, in turn, lead to the intensive formation of cumulus clouds, which are sources of heavy tropical downpours.

Wind speed measuring device

It is an anemometer, which consists of three cups located at an angle of 120 o relative to each other, and fixed on a vertical axis. The operating principle of an anemometer is quite simple. When the wind blows, the cups experience its pressure and begin to rotate on their axis. The stronger the air pressure, the faster they rotate. By measuring the speed of this rotation, you can accurately determine the wind speed in m/s (meters per second). Modern anemometers are equipped with special electrical systems that independently calculate the measured value.

The wind speed device based on the rotation of the cups is not the only one. There is another simple tool called a pitot tube. This device measures the dynamic and static pressure of the wind, from the difference of which its speed can be accurately calculated.

Beaufort scale

Information about wind speed expressed in meters per second or kilometers per hour does not mean much to most people - and especially to sailors. Therefore, in the 19th century, the English admiral Francis Beaufort proposed using some empirical scale for assessment, which consists of a 12-point system.

The higher the Beaufort scale, the stronger the wind blows. For example:

• The number 0 corresponds to absolute calm. With it, the wind blows at a speed not exceeding 1 mile per hour, that is, less than 2 km/h (less than 1 m/s).
• The middle of the scale (number 6) corresponds to a strong breeze, the speed of which reaches 40-50 km/h (11-14 m/s). Such a wind is capable of raising large waves on the sea.
• The maximum on the Beaufort scale (12) is a hurricane whose speed exceeds 120 km/h (more than 30 m/s).

The main winds on planet Earth

In the atmosphere of our planet, they are usually classified as one of four types:

• Global. They are formed as a result of the different ability of continents and oceans to heat up from the sun's rays.
• Seasonal. These winds vary depending on the season of the year, which determines how much solar energy a certain area of ​​the planet receives.
• Local. They are related to the peculiarities of the geographical location and topography of the area in question.
• Rotating. These are the strongest movements of air masses that lead to the formation of hurricanes.

Why is it important to study winds?

In addition to the fact that information about wind speed is included in the weather forecast, which every inhabitant of the planet takes into account in his life, air movement plays a large role in a number of natural processes.

Thus, it is a carrier of plant pollen and participates in the distribution of their seeds. In addition, wind is one of the main sources of erosion. Its destructive effect is most pronounced in deserts, when the terrain changes dramatically during the day.

We should also not forget that wind is the energy that people use in economic activities. According to general estimates, wind energy makes up about 2% of all solar energy falling on our planet.

Accepted for use in international synoptic practice. It originally did not include wind speed (added in 1926). In 1955, to distinguish between hurricane winds of different strengths, the US Weather Bureau expanded the scale to 17 points.

It is worth noting that the wave heights in the scale are given for the open ocean, not the coastal zone.

Beaufort points	Verbal definition of wind force	Average wind speed, m/s	Average wind speed, km/h	Average wind speed, knots	Wind action
					on the land	on the sea
0	Calm	0-0,2	< 1	0-1	Calm. Smoke rises vertically, tree leaves are motionless	Mirror smooth sea
1	Quiet	0,3-1,5	1-5	1-3	The direction of the wind is noticeable from the drift of the smoke, but not from the weather vane.	There are no ripples, no foam on the crests of the waves. Wave height up to 0.1 m
2	Easy	1,6-3,3	6-11	3,5-6,4	The movement of the wind is felt by the face, the leaves rustle, the weather vane is set in motion	Short waves with a maximum height of up to 0.3 m, the crests do not overturn and appear glassy
3	Weak	3,4-5,4	12-19	6,6-10,1	The leaves and thin branches of the trees sway all the time, the wind flutters light flags	Short, well defined waves. The ridges, overturning, form glassy foam. Occasionally small lambs are formed. Average wave height 0.6 m
4	Moderate	5,5-7,9	20-28	10,3-14,4	The wind raises dust and debris and moves thin tree branches	The waves are elongated, whitecaps are visible in many places. Maximum wave height up to 1.5 m
5	Fresh	8,0-10,7	29-38	14,6-19,0	Thin tree trunks sway, the movement of the wind is felt by the hand	Well-developed in length, but not large waves, maximum wave height 2.5 m, average - 2 m. Whitecaps are visible everywhere (in some cases splashes are formed)
6	Strong	10,8-13,8	39-49	19,2-24,1	Thick tree branches sway, telegraph wires hum	Large waves begin to form. White foamy ridges occupy large areas and splashes are likely. Maximum wave height - up to 4 m, average - 3 m
7	Strong	13,9-17,1	50-61	24,3-29,5	Tree trunks sway	The waves pile up, the crests of the waves break off, the foam lies in stripes in the wind. Maximum wave height up to 5.5 m
8	Very strong	17,2-20,7	62-74	29,7-35,4	The wind breaks tree branches, it is very difficult to walk against the wind	Moderately high long waves. Spray begins to fly up along the edges of the ridges. Strips of foam lie in rows in the direction of the wind. Maximum wave height up to 7.5 m, average - 5.5 m
9	Storm	20,8-24,4	75-88	35,6-41,8	Minor damage, the wind begins to destroy the roofs of buildings	High waves (maximum height - 10 m, average - 7 m). The foam falls in wide dense stripes in the wind. The crests of the waves begin to capsize and crumble into spray, which impairs visibility
10	Heavy storm	24,5-28,4	89-102	42,0-48,8	Significant damage to buildings, wind uprooting trees	Very high waves (maximum height - 12.5 m, average - 9 m) with long crests curving down. The resulting foam is blown away by the wind in large flakes in the form of thick white stripes. The surface of the sea is white with foam. The strong crash of the waves is like blows
11	Fierce Storm	28,5-32,6	103-117	49,0-56,3	Large destruction over a large area. It is observed very rarely.	Visibility is poor. Exceptionally high waves (maximum height - up to 16 m, average - 11.5 m). Small and medium-sized vessels are sometimes hidden from view. The sea is all covered with long white flakes of foam, located downwind. The edges of the waves are blown into foam everywhere
12	Hurricane	> 32,6	> 117	> 56	Enormous destruction, buildings, structures and homes were seriously damaged, trees were uprooted, vegetation was destroyed. The case is very rare.	Exceptionally poor visibility. The air is filled with foam and spray. The sea is all covered with stripes of foam
13
14
15
16
17

see also

Links

• Description of the Beaufort scale with photographs of the state of the sea surface.

Wikimedia Foundation. 2010.

• Baikal (spaceship)
• Nonmetals

See what the “Beaufort Scale” is in other dictionaries:

BEAUFORT SCALE- (Beaufort scale) at the beginning of the 19th century. English Admiral Beaufort proposed to determine the wind force by the windage that the ship itself or other sailing ships in its visibility can carry at the moment of observation, and to evaluate this force with scale points ... ... Maritime Dictionary

Beaufort scale- a conventional scale for visually assessing the strength (speed) of wind, based on its impact on ground objects or on the water surface. Used primarily for ship observations. Has 12 points: 0 calm (0 0.2 m/s), 4 moderate... ... Dictionary of emergency situations

Beaufort scale- A scale for determining wind strength, based on a visual assessment of the state of the sea, expressed in points from 0 to 12 ... Dictionary of Geography

Beaufort scale- 3.33 Beaufort scale: A twelve-point scale adopted by the World Meteorological Organization to approximate wind speed by its effect on objects on land or by waves on the high seas. Source … Dictionary-reference book of terms of normative and technical documentation

Beaufort scale- a scale for determining wind strength by visual assessment, based on the effect of wind on the state of the sea or on land objects (trees, buildings, etc.). Used primarily for observations from sea vessels. Adopted in 1963 by the World... ... Geographical encyclopedia

A conventional scale in points in the form of a table for expressing the speed (strength) of the wind by its effect on ground objects, by rough seas and the ability of the wind to propel sailing ships. The scale was proposed in 1805-1806. British Admiral F. ... ... Dictionary of winds

BEAUFORT SCALE- wind force assessment system. Proposed by the English hydrographer F. Beaufort in 1806. It is based on the visual perception of the effect of wind on the water surface, smoke, flags, ship superstructures, on the shore, and structures. The assessment is made in points... ... Marine encyclopedic reference book

Beaufort scale- a conventional scale in points from 0 to 12 for a visual assessment of the strength (speed) of the wind in points based on roughness at sea or on the effect of ground objects: 0 points (no wind 0 0.2 m/s); 4 moderate wind (5.5 7.9 m/s); 6 strong wind (10.8 13.8 m/s); 9… … Glossary of military terms

BEAUFORT SCALE- In damage management: a conventional scale for visually assessing and recording wind strength (speed) in points or sea waves. It was developed and proposed by the English admiral Francis Beaufort in 1806. Since 1874 it has been adopted for use in... ... Insurance and risk management. Terminological dictionary

Beaufort scale- The Beaufort scale is a twelve-point scale adopted by the World Meteorological Organization to approximate wind speed by its effect on land objects or by waves on the high seas. Average wind speed is indicated on... ... Wikipedia

Beaufort scale- a conventional scale for visually assessing the strength (speed) of the wind in points based on its effect on ground objects or on sea waves. It was developed by the English admiral F. Beaufort in 1806 and at first was used only by him. In 1874, the Standing Committee of the First Meteorological Congress adopted the Beaufort scale for use in international synoptic practice. In subsequent years, the scale was changed and refined. The Beaufort scale is widely used in maritime navigation.

Wind strength at the earth's surface on the Beaufort scale (at a standard height of 10 m above an open, level surface)
Beaufort points	Verbal definition of wind force	Wind speed, m/sec	Wind action
			on the land	on the sea
0	Calm	0-0,2	Calm. Smoke rises vertically	Mirror smooth sea
1	Quiet	0,3-1,5	The direction of the wind is noticeable from the drift of the smoke, but not from the weather vane.	Ripples, no foam on the ridges
2	Easy	1,6-3,3	The movement of the wind is felt by the face, the leaves rustle, the weather vane is set in motion	Short waves, crests do not capsize and appear glassy
3	Weak	3,4-5,4	The leaves and thin branches of the trees sway all the time, the wind flutters the upper flags	Short, well defined waves. The ridges, overturning, form a glassy foam, occasionally small white lambs are formed
4	Moderate	5,5-7,9	The wind raises dust and pieces of paper and moves thin tree branches.	The waves are elongated, white caps are visible in many places
5	Fresh	8,0-10,7	Thin tree trunks sway, waves with crests appear on the water	Well developed in length, but not very large waves, white caps are visible everywhere (in some cases splashes are formed)
6	Strong	10,8-13,8	Thick tree branches sway, telegraph wires hum	Large waves begin to form. White foamy ridges occupy large areas (splashes are likely)
7	Strong	13,9-17,1	The tree trunks are swaying, it’s difficult to walk against the wind	The waves pile up, the crests break off, the foam lies in stripes in the wind
8	Very strong	17,2-20,7	The wind breaks tree branches, it is very difficult to walk against the wind	Moderately high long waves. Spray begins to fly up along the edges of the ridges. Strips of foam lie in rows in the direction of the wind
9	Storm	20,8-24,4	Minor damage; the wind tears off smoke hoods and tiles	High waves. The foam falls in wide dense stripes in the wind. The crests of the waves begin to capsize and crumble into spray, which impairs visibility
10	Heavy storm	24,5-28,4	Significant destruction of buildings, trees are uprooted. Rarely happens on land	Very high waves with long, downward-curving crests. The resulting foam is blown away by the wind in large flakes in the form of thick white stripes. The surface of the sea is white with foam. The strong roar of the waves is like blows. Visibility is poor
11	Fierce Storm	28,5-32,6	Large destruction over a large area. Very rarely observed on land	Exceptionally high waves. Small and medium-sized vessels are sometimes hidden from view. The sea is all covered with long white flakes of foam, located downwind. The edges of the waves are blown into foam everywhere. Visibility is poor
12	Hurricane	32.7 or more		The air is filled with foam and spray. The sea is all covered with stripes of foam. Very poor visibility

Each natural phenomenon, which has different degrees of severity, is usually assessed in accordance with certain criteria. Especially if information about it must be transmitted quickly and accurately. For wind strength, the Beaufort scale has become a common international reference point.

Developed by the British rear admiral, a native of Ireland, Francis Beaufort (accent on the second syllable) in 1806, the system, improved in 1926 by adding information about the equivalence of wind strength in points to its specific speed, allows you to fully and accurately characterize this atmospheric process, while remaining relevant and to this day.

What is wind?

Wind is the movement of air masses parallel to the surface of the planet (horizontally above it). This mechanism is caused by pressure differences. The direction of movement always comes from a higher area.

The following characteristics are commonly used to describe wind:

• speed (measured in meters per second, kilometers per hour, knots and points);
• wind force (in points and m.s. - meters per second, the ratio is approximately 1:2);
• direction (according to the cardinal points).

The first two parameters are closely related. They can be mutually designated by each other's units of measurement.

The direction of the wind is determined by the side of the world from which the movement began (from the north - north wind, etc.). The speed is determined by the pressure gradient.

Pressure gradient (otherwise known as barometric gradient) is the change in atmospheric pressure per unit distance normal to a surface of equal pressure (isobaric surface) in the direction of decreasing pressure. In meteorology, they usually use the horizontal barometric gradient, that is, its horizontal component (Great Soviet Encyclopedia).

Wind speed and strength cannot be separated. A large difference in indicators between atmospheric pressure zones gives rise to strong and rapid movement of air masses above the earth's surface.

Features of wind measurement

In order to correctly correlate weather service data with your actual position or make a correct measurement, you need to know what standard conditions professionals use.

• Wind force and speed are measured at a ten-meter height on an open, flat surface.
• The name of the direction of the wind is given by the cardinal direction from which it blows.

Water transport managers, as well as those who like to spend time in nature, often purchase anemometers that determine speed, which is easily correlated with wind force in points. There are waterproof models. For convenience, devices of various compactness are produced.

In the Beaufort system, a description of wave heights associated with a certain wind force in points is given for open sea space. It will be significantly less in shallow waters and coastal areas.

From personal to global use

Sir Francis Beaufort not only had a high military rank in the navy, but was also a successful practical scientist who held important positions, a hydrographer and cartographer who brought great benefit to the country and the world. One of the seas in the Arctic Ocean, washing Canada and Alaska, bears his name. An Antarctic island is named after Beaufort.

Francis Beaufort created a convenient system for estimating wind force in points, available for fairly accurately determining the severity of the phenomenon “by eye,” for his own use in 1805. The scale ranged from 0 to 12 points.

In 1838, a system of visual assessment of weather and wind force in points became officially used by the British fleet. In 1874 it was adopted by the international synoptic community.

In the 20th century, several more improvements were made to the Beaufort scale - the ratio of points and verbal description of the manifestation of the elements with wind speed (1926), and five more divisions were added - points for grading the strength of hurricanes (USA, 1955).

Criteria for estimating wind force in Beaufort points

In its modern form, the Beaufort scale has several characteristics that make it possible to most accurately correlate a specific atmospheric phenomenon with its indicators in points.

• Firstly, this is verbal information. Verbal description of the weather.
• Average speed in meters per second, kilometers per hour and knots.
• The impact of moving air masses on characteristic objects on land and sea is determined by typical manifestations.

Harmless wind

Safe wind is determined in the range from 0 to 4 points.

	Name	Wind speed (m/s)	Wind speed (km/h)		Description	Characteristic
	Calm, complete calm (Calm)		less than 1 km/h		The movement of smoke is vertically upward, the leaves of the trees do not move	The surface of the sea is motionless, smooth
	Quiet Wind (Light Air)				The smoke has a slight angle of inclination, the weather vane is motionless	Light ripples without foam. Waves no higher than 10 centimeters
	Light Breeze				You can feel the wind blowing on your face, there is movement and rustling of leaves, slight movement of the weather vane	Short, low waves (up to 30 centimeters) with a glass-like comb
	Weak (Gentle Breeze)				Continuous movement of foliage and thin branches on the trees, swaying flags	The waves remain short but are more noticeable. The ridges begin to tip over and turn into foam. Rare small “lambs” appear. The height of the waves reaches 90 centimeters, but on average does not exceed 60
	Moderate Breeze				Dust and small debris begin to rise from the ground	The waves become longer and rise up to one and a half meters. "Lambs" appear often

A wind of 5 points, characterized as “fresh”, or fresh breeze, can be called borderline. Its speed ranges from 8 to 10.7 meters per second (29-38 km/h, or 17 to 21 knots). Thin trees sway along with their trunks. Waves rise up to 2.5 (on average two) meters. Sometimes splashes appear.

The wind that brings trouble

With a wind force of 6, strong phenomena begin that can cause damage to health and property.

Points	Name	Wind speed (m/s)	Wind speed (km/h)	Wind speed (sea speed)	Description	Characteristic
	Strong Breeze				Thick tree branches sway strongly, the hum of telegraph wires can be heard	Large waves form, foam crests acquire significant volume, and splashes are likely. The average wave height is about three meters, the maximum reaches four
	Strong (Moderate gale)				The trees are completely swaying	Active movement of waves up to 5.5 meters high, overlapping each other, scattering of foam along the line of wind movement
	Very strong (Gale)				Tree branches break due to the pressure of the wind, making it difficult to walk against the direction of the wind	Waves of considerable length and height: average - about 5.5 meters, maximum - 7.5 m. Moderately high long waves. Sprays fly up. The foam falls in stripes, the vector coincides with the direction of the wind
	Storm (Strong gale)				The wind damages buildings and begins to destroy roof tiles	Waves up to ten meters with an average height of up to seven. The foam stripes become wider. Overturning ridges scatter in spray. Visibility is reduced

Dangerous wind force

Winds with a force of ten to twelve are dangerous and are characterized as a strong and violent storm, as well as a hurricane.

The wind uproots trees, damages buildings, destroys vegetation, and destroys buildings. The waves emit deafening noise from 9 meters and above, and are long. At sea, they reach dangerous heights even for large ships - from nine meters and above. Foam covers the water surface, visibility is zero or close to this.

The speed of movement of air masses ranges from 24.5 meters per second (89 km/h) and reaches from 118 kilometers per hour with a wind force of 12 points. Severe storms and hurricanes (winds equal to 11 and 12 points) occur very rarely.

Additional five points to the classic Beaufort scale

Since hurricanes are also not identical in intensity and degree of damage, in 1955 the United States Weather Bureau adopted an addition to the standard Beaufort classification in the form of five scale units. Wind strength from 13 to 17 points inclusive are specific characteristics for destructive hurricane winds and accompanying environmental phenomena.

How to protect yourself when disaster strikes?

If a storm warning from the Ministry of Emergency Situations occurs in an open area, it is better to follow the advice and reduce the risk of accidents.

First of all, you should pay attention to the warnings every time - there is no guarantee that an atmospheric front will come to the area where you are, but you also cannot be sure that it will bypass it again. All items should be removed or securely secured to protect pets.

If a strong wind hits a fragile structure - a garden house or other light structures - it is better to close the windows on the side of the air movement and, if necessary, strengthen them with shutters or boards. From the leeward side, on the contrary, open it slightly and fix it in this position. This will eliminate the danger of an explosive effect from the pressure difference.

It is important to remember that any strong wind can bring with it unwanted precipitation - in winter there are blizzards and blizzards, in summer dust and sand storms are possible. It should also be taken into account that strong winds can occur even in absolutely clear weather.

Accepted for use in international synoptic practice. It originally did not include wind speed (added in 1926). In 1955, to distinguish between hurricane-force winds of different strengths, the US Weather Bureau expanded the scale to 17 points.

Beaufort points	Verbal definition of wind force	Average wind speed, m/s (km/h)	Average wind speed, knots	Wind action
0	Calm	0-0,2 (< 1)	0-1	The smoke rises vertically, the leaves of the trees are motionless. Mirror smooth sea
1	Quiet	0,3-1,5 (1-5)	1-3	The smoke deviates from the vertical direction, there are light ripples on the sea, there is no foam on the ridges. Wave height up to 0.1 m
2	Easy	1,6-3,3 (6-11)	3,5-6,4	You can feel the wind on your face, the leaves rustle, the weather vane begins to move, there are short waves at sea with a maximum height of up to 0.3 m
3	Weak	3,4-5,4 (12-19)	6,6-10,1	The leaves and thin branches of the trees are swaying, light flags are swaying, there is a slight disturbance on the water, and occasionally small “lambs” form. Average wave height 0.6 m
4	Moderate	5,5-7,9 (20-28)	10,3-14,4	The wind raises dust and pieces of paper; Thin branches of trees sway, white “lambs” on the sea are visible in many places. Maximum wave height up to 1.5 m
5	Fresh	8,0-10,7 (29-38)	14,6-19,0	Branches and thin tree trunks sway, you can feel the wind with your hand, and white “lambs” are visible on the water. Maximum wave height 2.5 m, average - 2 m
6	Strong	10,8-13,8 (39-49)	19,2-24,1	Thick tree branches sway, thin trees bend, telephone wires hum, umbrellas are difficult to use; white foamy ridges occupy large areas, and water dust is formed. Maximum wave height - up to 4 m, average - 3 m
7	Strong	13,9-17,1 (50-61)	24,3-29,5	Tree trunks sway, large branches bend, it is difficult to walk against the wind, wave crests are torn off by the wind. Maximum wave height up to 5.5 m
8	Very strong	17,2-20,7 (62-74)	29,7-35,4	Thin and dry branches of trees break, it is impossible to speak in the wind, it is very difficult to walk against the wind. Strong seas. Maximum wave height up to 7.5 m, average - 5.5 m
9	Storm	20,8-24,4 (75-88)	35,6-41,8	Large trees are bending, the wind is tearing tiles off the roofs, very rough seas, high waves (maximum height - 10 m, average - 7 m)
10	Heavy storm	24,5-28,4 (89-102)	42,0-48,8	Rarely happens on land. Significant destruction of buildings, wind knocks down trees and uproots them, the surface of the sea is white with foam, strong crashing waves are like blows, very high waves (maximum height - 12.5 m, average - 9 m)
11	Fierce Storm	28,5-32,6 (103-117)	49,0-56,3	It is observed very rarely. Accompanied by destruction over large areas. The sea has exceptionally high waves (maximum height - up to 16 m, average - 11.5 m), small vessels are sometimes hidden from view
12	Hurricane	> 32,6 (> 117)	> 56	Serious destruction of capital buildings

see also

Links

• Description of the Beaufort scale with photographs of the state of the sea surface.

Wikimedia Foundation. 2010.

See what the “Beaufort scale” is in other dictionaries:

Modern encyclopedia

BEAUFORT SCALE, a series of numbers from 0 to 17 corresponding to the strength of the wind, supplemented by a description of the accompanying phenomena on land or sea. The number 0 means a light breeze of less than 1 km/h, in which the column of smoke rises vertically. Number 3... Scientific and technical encyclopedic dictionary

See Beaufort Scale. EdwART. Dictionary of terms of the Ministry of Emergency Situations, 2010 ... Dictionary of emergency situations

Beaufort scale- BEAUFORT SCALE, a conventional 12-point scale for expressing wind strength (speed) by visual assessment. Widely used in marine navigation. Zero on the Beaufort scale calm (no wind), 4 points moderate wind, 6 points strong wind, 10 points storm... Illustrated Encyclopedic Dictionary

A conditional 12-point scale proposed by F. Beaufort in 1806 for assessing the strength of the wind by its effect on ground objects and by the state of the sea: 0 calm (calm), 4 moderate wind, 6 strong wind, 10 storm (storm), 12 hurricane... Big Encyclopedic Dictionary

beaufort scale- a conditional scale for assessing the strength of the wind in points based on its effect on land objects and on the state of the sea: 0 calm (calm wind), 4 moderate wind, 6 strong wind, 10 storm (strong storm), 12 hurricane... Marine Biographical Dictionary

Conventional designation, proposed by Beaufort, of wind force points, determined visually by its various manifestations. B. sh. has 12 points, the following values ​​are assigned to the eye: 0 calm, smoke rises vertically, tree leaves are motionless; 1 … Technical railway dictionary

A conditional 12-point scale proposed by F. Beaufort in 1806 for assessing the strength of the wind by its effect on land objects and by the state of the sea: 0 calm (calm), 4 moderate wind, 6 strong wind, 10 storm (storm), 12 hurricane. * * *… … encyclopedic Dictionary

A conventional scale for visually assessing the strength (speed) of wind in points based on its effect on ground objects or on sea waves. It was developed by the English admiral F. Beaufort in 1806 and at first was used only by him. In 1874... ... Great Soviet Encyclopedia

Beaufort scale- (Beafort Scale)Beafort Scale, a scale for determining wind strength in points from 0 (calm) to 12 (hurricane). Named after its author, the English admiral Sir Francis Beaufort (1774-1857) ... Countries of the world. Dictionary