Weather buoy

Weather buoys are instruments which collect weather and ocean data within the world's oceans, as well as aid during emergency response to chemical spills, legal proceedings, and engineering design. Moored buoys have been in use since 1951, while drifting buoys have been used since 1979. Moored buoys are connected with the ocean bottom using either chains, nylon, or buoyant polypropylene. With the decline of the weather ship, they have taken a more primary role in measuring conditions over the open seas since the 1970s. During the 1980s and 1990s, a network of buoys in the central and eastern tropical Pacific Ocean helped study the El Niño-Southern Oscillation. Moored weather buoys range from 1.5 metres (4.9 ft) to 12 metres (39 ft) in diameter, while drifting buoys are smaller, with diameters of 30 centimetres (12 in) to 40 centimetres (16 in). Drifting buoys are the dominant form of weather buoy in sheer number, with 1250 located worldwide. Wind data from buoys has smaller error than that from ships. There are differences in the values of sea surface temperature measurements between the two platforms as well, relating to the depth of the measurement and whether or not the water is heated by the ship which measures the quantity.

The first known proposal for surface weather observations at sea occurred in connection with aviation in August 1927, when Grover Loening stated that "weather stations along the ocean coupled with the development of the seaplane to have an equally long range, would result in regular ocean flights within ten years." Starting in 1939, United States Coast Guard vessels were being used as weather ships to protect transatlantic air commerce.

During World War II The German Navy deployed weather buoys (Wetterfunkgerät See — WFS) at fifteen fixed positions in the North Atlantic and Barents Sea. They were launched from U-boats into a maximum depth of ocean of 1000 fathoms (1,800 metres), limited by the length of the anchor cable. Overall height of the body was 10.5 metres (of which most was submerged), surmounted by a mast and extendible aerial of 9 metres. Data (air and water temperature, atmospheric pressure and relative humidity) were encoded and transmitted four times a day. When the batteries (high voltage dry-cells for the valves, and nickel-iron for other power and to raise and lower the aerial mast) were exhausted, after about eight to ten weeks, the unit self-destructed.

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