The Beaufort Scale: A Comprehensive Guide摘要：The Beaufort Scale: A Comprehensive Guide
Introduction
The Beaufort Scale is a method of measuring wind speed based on the visual effects of the wind on the sea
Introduction
The Beaufort Scale is a method of measuring wind speed based on the visual effects of the wind on the sea. It was invented by Sir Francis Beaufort, an Irish Royal Navy officer, in 1805. The scale ranges from 0 to 12, with 0 being a calm sea and 12 being hurricane-force winds. In this article, we will discuss each level of the Beaufort Scale in detail.
Level 0: Calm
When the sea is calm, there is no wind and the water is like glass. There are no visible ripples on the surface of the water. This is a rare occurrence and usually occurs in sheltered bays or harbors.
Level 1: Light Air
The wind speed at this level is less than 1 knot. The air may move branches on trees and the wind direction is indicated by the movement of smoke. There are small wind-generated ripples on the water, but they don't affect the overall appearance of the sea.
Level 2: Light Breeze
At this level, the wind speed is between 1 and 3 knots. Small wavelets are visible on the water and the leaves on trees rustle. Wind direction is more clearly shown by the movement of flags and wind vanes.
Level 3: Gentle Breeze
When the wind speed is between 4 and 6 knots, the sea begins to show slight signs of choppy water. There are larger wavelets on the water and some whitecaps may appear. Small branches on trees move and dust and loose paper are blown around.
Level 4: Moderate Breeze
A wind speed of 7 to 10 knots creates more pronounced whitecaps on the water, as well as larger waves. The wind can be felt on the face and hair and causes dust and loose paper to be blown around more forcefully. Small trees begin to sway.
Level 5: Fresh Breeze
A wind speed of 11 to 16 knots creates considerable whitecaps and small waves. Spray may begin to be blown off the tops of waves. Large branches on trees begin to move and loose objects are blown around. This is the point at which sailing vessels may begin to struggle with the wind.
Level 6: Strong Breeze
At this level, with a wind speed of 17 to 21 knots, large waves begin to form and the sea becomes rough. The wind can be heard whistling through telephone wires and moderate-sized trees sway. It is difficult to walk against the wind.
Level 7: Near Gale
With a wind speed of 22 to 27 knots, the sea becomes very rough and the waves are large and high. Foam is blown off the tops of waves in well-formed white streaks. Walking becomes extremely difficult and there is a strong pulling effect on clothing.
Level 8: Gale
At this level, with a wind speed of 28 to 33 knots, the sea is truly dangerous for small craft. Large waves and enormous amounts of foam are formed, and the sea is covered with white crests. Trees uprooted and damage is caused to buildings.
Level 9: Strong Gale
When the wind speed reaches 34 to 40 knots, the sea is extremely dangerous for all vessels. Waves break with such frequency that the sea appears to be completely white. Large trees blow down and structural damage to buildings occurs.
Level 10: Storm
With a wind speed of 41 to 47 knots, the sea is incredibly dangerous for all vessels. The waves are exceptionally high and the sea is covered with white foam patches. Walking becomes impossible and widespread structural damage occurs.
Level 11: Violent Storm
At this level, with a wind speed of 48 to 55 knots, sailing vessels are in serious danger and the sea is extremely hazardous for all vessels. The waves are enormous and seasickness is common. There is widespread structural damage, including to houses and other buildings.
Level 12: Hurricane Force
When the wind speed exceeds 55 knots and the sea is covered in foam and spray, the wind becomes a hurricane. The sea is unrecognizable from the shore, with waves as high as 60 feet. Trees are uprooted and significant damage is caused to buildings.
Conclusion
The Beaufort Scale is a necessary tool for sailors, fishermen, and anyone whose livelihood depends on the sea. Understanding the different levels of wind speed and their corresponding visual effects can help ensure the safety of both people and property. With this knowledge, sailors and other sea-goers can take appropriate precautions when the wind begins to pick up, and stay safe when sea conditions become hazardous.
