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Buoy

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A buoy is a versatile floating device used for a wide variety of maritime and scientific purposes. These objects can be anchored to the seabed to remain stationary, or they can be allowed to drift freely with ocean currents.

Paul Signac La bouee rouge
Paul Signac La bouee rouge

They serve as critical tools for navigation, safety, and environmental monitoring. By marking specific locations, buoys help prevent accidents and provide essential data about the world's oceans.

The history of buoys reveals a long evolution of design and technology. While their exact origins are unknown, a seaman's manual from 1295 mentions navigation buoys in the Guadalquivir River in Spain. In the Dutch Maasmond, records from 1358 describe the use of barrel buoys. Because simple barrels were difficult to secure to the seabed, engineers developed the conical tonne. This design featured a solid plug at the narrow end to attach a mooring ring. By 1790, these were being replaced by nun buoys, which used a barrel shape at the waterline and a conical section below it.

Lateral Buoy
Lateral Buoy

In the nineteenth century, manufacturers began producing iron buoys. These featured watertight internal bulkheads and could be equipped with bells or whistles to signal their presence.

Lighting technology changed how buoys functioned at night. In 1879, Julius Pintsch patented a method to illuminate buoys using compressed gas. This was later superseded starting in 1912 by the acetylene lamp developed by Gustaf Dalén. This lamp could be set to flash, allowing sailors to distinguish a buoy from a ship's lights. Dalén also developed the sun valve, which automatically shut off the gas during daylight hours. Modern versions often use solar panels and LED lights to provide visibility.

Red and green light navigation buoys
Red and green light navigation buoys

Navigational buoys are categorized by their specific roles in guiding vessels. Race course marker buoys are used in yacht and powerboat racing to delimit a course. Emergency wreck buoys are used to mark new shipwrecks for the first 24 to 72 hours. These are highly visible, featuring alternating blue and yellow vertical stripes and flashing lights.

NOAA-NDBC-discus-buoy
NOAA-NDBC-discus-buoy

Large Navigational Buoys, or Lanby buoys, are automatic devices over 10 meters high. They use powerful lights and electronic monitoring to replace traditional lightvessels. On maritime charts, these are sometimes referred to as "Superbuoys."

Other types of buoys serve specialized commercial and recreational needs. Lobster trap buoys are brightly colored so fishers can locate their gear in poor visibility. Each fisher uses unique colors or registration numbers to identify their specific traps. In the world of diving, several marker buoys are used for safety. Decompression buoys mark a diver's position during decompression stops, while surface marker buoys help identify a diver's location to boats. Divers also use dive site demarcation buoys to warn passing vessels to stay clear of their working area.

Scientific research relies heavily on sophisticated buoy systems to study the Earth. Profiling buoys are specialized tools that adjust their buoyancy to sink at controlled rates. For example, they can sink to depths of 2,000 meters to measure sea temperature and salinity. After about 10 days, they return to the surface to transmit data via satellite. Tsunami buoys are anchored to detect sudden changes in undersea water pressure, providing warnings for the Pacific Tsunami Warning Center. Weather buoys, also known as Ocean Data Acquisition Systems (ODAS), measure air temperature, wind speed, and barometric pressure. They transmit this information via satellite radio links to meteorological centers for climate study.

Buoys also play roles in military operations and search and rescue. Military marker buoys can emit light or smoke using pyrotechnic devices to create flares. Sonobuoys are used by aircraft to detect submarines using SONAR technology. For human safety, lifebuoys are thrown to people in the water to provide buoyancy. Self-locating datum marker buoys (SLDMB) are used in search and rescue operations. These devices have very little surface area above the water to minimize the impact of wind and waves.

Arrival Polar
Arrival Polar

Beyond the ocean, the concept of the buoy has appeared in unexpected places. The word "buoyed" is even used figuratively to describe lifting someone's spirits. In a surprising connection to everyday life, George A. Stephen used a metal buoy to help invent the Weber Kettle Grill. He cut a buoy in half to create the characteristic dome shape of the grill. From deep-sea research to backyard cooking, the influence of the buoy is quite widespread.

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🖼️ Images & Media (5)
File:Lateral Buoy.jpg
Lateral Buoy.jpg
File:NOAA-NDBC-discus-buoy.jpg
NOAA-NDBC-discus-buoy.jpg
File:Paul Signac La bouee rouge.jpg
Paul Signac La bouee rouge.jpg
Red and green light navigation buoys.webp
File:Arrival Polar.jpg
Arrival Polar.jpg
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