From Glossary of Meteorology
A floating platform used in operations and research to collect meteorological and oceanographic data for forecasting, describing environmental conditions, and research, as well as for navigational purposes. Buoys can be stationary (anchored) or carried by ocean currents (drifter) either on the surface or at fixed or varying depths. Some buoys are designed for a single purpose such observing tsunami waves. Surface and subsurface buoys can obtain measurements of temperature, wind, salinity, and biogeochemical parameters (e.g., fluorometry, chlorophyll, pH, or oxygen). Drifting buoys can provide position information that is used to calculate currents. Surface and subsurface drogues can provide information on the currents at any chosen depth or density horizon.
The buoys themselves can take many shapes. Some buoys are toroidal/doughnut-shaped, some look like tubes, some simply appear as a floating ball, and others resemble a small boat or even a surf board. Standard buoys as wide as 12 m in diameter with a 10 m mast were once used by NOAA’s National Data Buoy Center for stability in areas of historically bad weather. Those large buoys have been replaced with smaller 3-m-diameter buoys. While some do in fact measure a single element, most are used for multiple measurements with the data retrieved via satellite for operational use on a daily basis.
Term edited 29 May 2020.