radiosonde

radiosonde , group of instruments for simultaneous measurement and radio transmission of meteorological data, including temperature, pressure, and humidity of the atmosphere. The instrument package is usually carried into the atmosphere by a balloon (see weather balloon ); balloon-borne radiosondes reach altitudes as great as 90,000 ft (27,400 m) above the earth's surface. A radiosonde may also be carried by a rocket, in which case it is known as a rocketsonde, or dropped by parachute (usually from an aircraft), in which case it is known as a dropsonde. Instruments included in a radiosonde are typically transducers for humidity, temperature, and pressure measurements; controls to improve return signals and determine which measurements are to be transmitted to data stations; and a radio transmitter. Radar also has been used to measure and transmit meteorological data from a radiosonde. These radiosonde observations are made as often as four times daily at some meteorological stations around the globe.

radiosonde Instrument, comprising an aneroid barometer and sensors for temperature and humidity, that is carried aloft to the upper atmosphere by a balloon that ascends at about 5 m/s. Data is transmitted to the surface by radio. See also RAWINSONDE.

rawinsonde Radiosonde that is tracked by radio or radar to observe wind characteristics as well as to record temperature, pressure and humidity.