Beaufort scale - wind force and sea conditions. Wind speed, strength and direction Wind 15-20 m s is called
Wind speed can be assessed visually by its effect on objects surrounding the observer. In 1805 Francis Beaufort(Francis Beaufort), a sailor of the British Navy, developed a 12-point scale to characterize the strength of the wind at sea. allows you to estimate wind speed without using any instruments. In 1926, land wind speed estimates were added to this scale. To distinguish between hurricane-force winds of different strengths, the US Weather Bureau expanded the scale to 17 in 1955.
Today, the 12-point scale is adopted by the World Meteorological Organization for an approximate estimate of wind speed by its effect on ground objects or by waves in the open sea. Average wind speed is indicated at a standard height of 10 meters above an open, level surface. Sea roughness is also characterized by points, but different; the anxiety scale has nine points. The table below compares wave scores with wind scores. The wave parameters are given for open waters; in the coastal zone the waves are less.
Beaufort scale table
| Points. Designation. Speed in knots. | Signs on the shore | Sea surface condition | Excitement. Points. Characteristic. | Medium waves: height (m)/ period (s)/ length (m) |
| 0. Calm. 0-1 |
The smoke is vertical. | Mirror smooth surface. | 0. There is no excitement. | — |
| 1. Quiet. 1-3 |
The smoke barely deviates. | Ripple. | 1. Weak. The sea is calm. | 0,1 / 0,5 / 0,3 |
| 2. Lightweight. 4-6 |
The wind is barely felt on your face. The leaves are rustling. | Small wave crests appear. | 2. Low excitement. | 0,2 / 0,6 / 1- 2 |
| 3. Weak. 7-10 |
Leaves sway, smoke drifts in the wind. | Short waves. Small ridges, overturning, form glassy foam. | 3. Slight excitement. | 0,6 –1 / 2 / 6 |
| 4. Moderate. 11-16 |
Twigs sway, dust rises, waves run across the grass. | The waves are moderate and whitecaps are appearing. | 4.Moderate excitement. | 1-1,5 / 3 / 15 |
| 5. Fresh. 17-21 |
You can feel the wind with your hand and shake the branches. | Waves with frequent white caps and isolated splashes. | 4. Rough sea. | 1,5-2 / 5 / 30 |
| 6. Strong. 22-27 |
The trees bend, the forest rustles, the grass bends to the ground. | The beginning of the formation of a large wave, large foaming crests. | 5. Major disturbance. | 2-3 / 7 /50 |
| 7. Sturdy. 28-33 |
Wires hum, gear whistles, trees bend, it’s difficult to walk against the wind. | The waves pile up, the crests break, the foam falls in the wind. | 6. Strong excitement. | 3-5 / 8 / 70 |
| 8. Very strong. 34-40 |
To go against the wind, you have to bend down. Breaks thin branches and twigs. | The height and length of the waves are noticeably increased, stripes of foam lie in close rows downwind. | 7. Very strong excitement. | 5-7 / 10 / 100 |
| 9. Storm. 41-47 |
Large trees bend and break branches. | The waves are high, the crests capsizing and crumbling into spray. | 8.Very strong excitement. | 7-8 / 12 / 150 |
| 10. Strong storm. 48-55 |
Breaks individual trees. | The sea is foamy, water dust and spray are flying, poor visibility. | 8.Very strong. | 8-11 / 14 / 200 |
| 11. Fierce storm. 56-63 |
Significant damage, breaking tree trunks. | 9. Exceptional. | 11 / 16 / 250 | |
| 12. Hurricane. More than 63 |
Catastrophic destruction. | Exceptionally high waves, the sea is covered with flakes of foam, there is no visibility. | 9. Exceptional. | More than 11 / 18 / 300 |
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
Wind(the horizontal component of air movement relative to the earth's surface) is characterized by direction and speed.
Wind speed measured in meters per second (m/s), kilometers per hour (km/h), knots or Beaufort points (wind force). Knot is a maritime unit of speed, 1 nautical mile per hour, approximately 1 knot is equal to 0.5 m/s. The Beaufort scale (Francis Beaufort, 1774-1875) was created in 1805.
Direction of the wind(from where it blows) is indicated either in points (on a 16-point scale, for example, north wind - N, northeast - NE, etc.), or in angles (relative to the meridian, north - 360° or 0°, east - 90°, south – 180°, west – 270°), fig. 1.
| Name of the wind | Speed, m/s | Speed, km/h | Nodes | Wind force, points | Wind action | |
|---|---|---|---|---|---|---|
| Calm | 0 | 0 | 0 | 0 | The smoke rises vertically, the leaves of the trees are motionless. Mirror smooth sea | |
| Quiet | 1 | 4 | 1-2 | 1 | The smoke deviates from the vertical direction, there are slight ripples in the sea, there is no foam on the ridges. Wave height up to 0.1 m | |
| Easy | 2-3 | 7-10 | 3-6 | 2 | 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 | |
| Weak | 4-5 | 14-18 | 7-10 | 3 | 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” are formed. Average wave height 0.6 m | |
| Moderate | 6-7 | 22-25 | 11-14 | 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 | |
| Fresh | 8-9 | 29-32 | 15-18 | 5 | 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 | |
| Strong | 10-12 | 36-43 | 19-24 | 6 | 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 | |
| Strong | 13-15 | 47-54 | 25-30 | 7 | 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 | |
| Very strong | 16-18 | 58-61 | 31-36 | 8 | 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 | |
| Storm | 19-21 | 68-76 | 37-42 | 9 | Large trees are bending, the wind is tearing tiles off the roofs, very rough seas, high waves (maximum height - 10 m, average - 7 m) | |
| Heavy storm | 22-25 | 79-90 | 43-49 | 10 | 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) | |
| Fierce Storm | 26-29 | 94-104 | 50-56 | 11 | 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 | |
| Hurricane | More than 29 | More than 104 | More than 56 | 12 | Serious destruction of capital buildings |
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.
See what the “Beaufort Scale” is in other dictionaries:
- (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
A conventional scale for visually assessing the strength (speed) of wind based on its effect 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
A scale for determining wind strength by visual assessment, based on the effect of wind on sea conditions or on land objects (trees, buildings, etc.). Used primarily for observations from sea vessels. Adopted in 1963 by the World... ... Geographical encyclopedia
BEAUFORT SCALE- a conditional 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
The Beaufort scale is 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. Average wind speed is indicated on... ... Wikipedia
IA website.
Beaufort scale
0 points - calm
Mirror-smooth sea, almost motionless. The waves practically do not run onto the shore. The water looks more like a quiet lake backwater than a sea coast. There may be haze over the surface of the water. The edge of the sea merges with the sky so that the border is not visible. Wind speed 0-0.2 km/h.
1 point - quiet
There are light ripples on the sea. The height of the waves reaches up to 0.1 meters. The sea can still merge with the sky. You can feel a light, almost imperceptible breeze.
2 points - easy
Small waves, no more than 0.3 meters high. The wind speed is 1.6-3.3 m/s, you can feel it with your face. With such wind, the weather vane begins to move.
3 points - weak
Wind speed 3.4-5.4 m/s. Slight disturbance on the water, whitecaps appear occasionally. The average wave height is up to 0.6 meters. The weak surf is clearly visible. The weather vane spins without frequent stops, leaves on the trees, flags, etc. sway.
4 points - moderate
Wind - 5.5 - 7.9 m/s - raises dust and small pieces of paper. The weather vane spins continuously, thin tree branches bend. The sea is rough and whitecaps are visible in many places. Wave height is up to 1.5 meters.
5 points - fresh
Almost the entire sea is covered with whitecaps. Wind speed 8 - 10.7 m/s, wave height 2 meters. Branches and thin tree trunks sway.
6 points - strong
The sea is covered with white ridges in many places. The height of the waves reaches 4 meters, the average height is 3 meters. Wind speed 10.8 - 13.8 m/s. Thin tree trunks and thick tree branches bend, telephone wires hum.
7 points - strong
The sea is covered with white foamy ridges, which from time to time are blown off the surface of the water by the wind. The height of the waves reaches 5.5 meters, the average height is 4.7 meters. Wind speed 13.9 - 17.1 m/s. The middle tree trunks sway and the branches bend.
8 points - very strong
Strong waves, foam on every crest. The height of the waves reaches 7.5 meters, the average height is 5.5 meters. Wind speed 17.2 - 20 m/s. Walking against the wind is difficult, talking is almost impossible. Thin branches of trees break.
9 points - storm
High waves on the sea, reaching 10 meters; average height 7 meters. Wind speed 20.8 - 24.4 m/s. Large trees bend, medium branches break. The wind tears off poorly reinforced roof coverings.
10 points - severe storm
The sea is white. The waves crash onto the shore or against the rocks with a roar. The maximum wave height is 12 meters, the average height is 9 meters. The wind, with a speed of 24.5 - 28.4 m/s, tears off roofs and causes significant damage to buildings.
11 points - severe storm
High waves reach 16 meters, with an average height of 11.5 meters. Wind speed 28.5 - 32.6 m/s. Accompanied by great destruction on land.
12 points - hurricane
Wind speed 32.6 m/s. Serious damage to permanent structures. The wave height is more than 16 meters.
Sea state scale
Unlike the generally accepted twelve-point wind rating system, there are several ratings of sea waves.
The generally accepted ones are British, American and Russian assessment systems.
All scales are based on a parameter that determines the average height of significant waves.
This parameter is called Significance Wave Height (SWH).
In the American scale, 30% of significant waves are taken, in the British 10%, in the Russian 3%.
The height of the wave is calculated from the crest (the highest point of the wave) to the trough (the base of the trough).
Below is a description of wave heights:
- 0 points - calm,
- 1 point - ripple (SWH< 0,1 м),
- 2 points - weak waves (SWH 0.1 - 0.5 m),
- 3 points - light waves (SWH 0.5 - 1.25 m),
- 4 points - moderate waves (SWH 1.25 - 2.5 m),
- 5 points - rough seas (SWH 2.5 - 4.0 m),
- 6 points - very rough seas (SWH 4.0 - 6.0 m),
- 7 points - strong waves (SWH 6.0 - 9.0 m),
- 8 points - very strong waves (SWH 9.0 - 14.0 m),
- 9 points - phenomenal waves (SWH > 14.0 m).
Since it determines not the strength of the storm, but the height of the wave.
A storm is defined by Beaufort.
For the WH parameter for all scales, it is precisely part of the waves that is taken (30%, 10%, 3%) because the magnitude of the waves is not the same.
At a certain time interval there are waves, for example, 9 meters, as well as 5, 4, etc.
Therefore, each scale had its own SWH value, where a certain percentage of the highest waves is taken.
There are no instruments to measure wave height.
Therefore, there is no exact definition of the score.
The definition is conditional.
On the seas, as a rule, the wave height reaches 5-6 meters in height and up to 80 meters in length.
Visual range scale
Visibility is the maximum distance at which objects can be detected during the day and navigation lights at night.
Visibility depends on weather conditions.
In metrology, the influence of weather conditions on visibility is determined by a conventional scale of points.
This scale is a way of indicating the transparency of the atmosphere.
There are day and night visibility ranges.
Below is the daily visual range scale:
Up to 1/4 cable
About 46 meters. Very poor visibility. Dense fog or snowstorm.
Up to 1 cable
About 185 meters. Bad visibility. Thick fog or wet snow.
2-3 cables
370 - 550 meters. Bad visibility. Fog, wet snow.
1/2 mile
About 1 km. Haze, thick haze, snow.
1/2 - 1 mile
1 - 1.85 km. Average visibility. Snow, heavy rain
1 - 2 miles
1.85 - 3.7 km. Haze, haze, rain.
2 - 5 miles
3.7 - 9.5 km. Light haze, haze, light rain.
5 - 11 miles
9.3 - 20 km. Good visibility. The horizon is visible.
11 - 27 miles
20 - 50 km. Very good visibility. The horizon is clearly visible.
27 miles
Over 50 km. Exceptional visibility. The horizon is clearly visible, the air is transparent.