Meteorology: Random Listings 

A thermodynamic change of state in a system in which there is no transfer of heat or mass across the boundaries of the system. In an adiabatic process, compression always results in warming, expansion in cooling. Compare to diabatic process.

A transducer which converts electromagnetic radiation in the infrared, visible, and ultraviolet regions into electrical quantities such as voltage, current, or resistance. Also called photo cell.

An estimate of the temperature of an incandescent body, determined by observing the wavelength at which it is emitting with peak intensity (its color) and using that wavelength in Wien's law.

An ion counter of the aspiration condenser type, used for the measurement of the concentration and mobility of small ions in the atmosphere.

An instrument, located at the surface observing station, which is used to record the data presented by a radiosonde aloft.

A motorlike device containing a rotor and a stator and capable of converting an angular position into an electrical signal, or an electrical signal into an angular position. When several synchros are correctly connected, all of the rotors will align thems ...

A radiosonde whose carrier wave is modulated by audio-frequency signals whose frequency is controlled by the sensing elements of the instrument.

Ice crystal deposits formed by sublimation (conversion of water vapor directly to ice) when temperature and dew point are below freezing.

A river gauge in which a weight suspended on a wire is lowered to the water surface from a bridge or other overhead structure to measure the distance from a point of known elevation to the water surface.

Pertaining to the action or effect of the wind. Derived from the name of the Greek god of the winds, Aeolus.

The maximum distance along the runway at which the runway lights are visible to a pilot at touchdown. Runway visual range may be determined by an observer located at the end of the runway, facing in the direction of landing, or by means of a transmissomet ...

A chronograph used to make a time-record of certain measured meteorological elements. The most common type, the triple register, records wind direction and speed, duration of sunshine, and amount of rainfall (sensed respectively by a contact anemometer, M ...

An instrument for studying, or examining substances in, polarized light. See Savant polariscope.

Apparatus using the combined simultaneous action of a bimetallic thermometer and a hair hygrometer to move a needle in front of a divided scale. fts construction permits dew point variations to be indicated approximately.

A severe weather condition characterized by low temperatures and strong winds bearing a great amount of snow, either falling or picked up from the ground.