Same as dropsonde.

The transmission of data collected at a remote location over communications channels to a central station.

The state of the atmosphere, mainly with respect to its effects upon life and human activities. As distinguished from climate, weather consists of the short-term (minutes to months) variations of the atmosphere.

An instrument used for the determination of the electrical conductivity of the atmosphere.

A temperature-sensing element which converts thermal energy directly into electrical energy. In its basic form it consists of two dissimilar metallic conductors connected in a closed loop. Each junction forms a thermocouple. If one thermocouple is maintai ...

A thermometer which uses a transducing element whose element proper-ties are a function of its thermal state. Common meteorological examples of such thermometers are the resistance thermometer and the thermoelectric thermometer.

The lowest level at which the wind becomes geostrophic in the theory of the Ekman spiral. Also called gradient wind level.

Any twelve-month period, usually selected to begin and end during a relative dry season. Used a basis for processing streamflow and other hydrologic data. The period from October 1 to September 30 is widely used in the U.S.

Sir Napier Shaw's name for the approximate absolute temperature scale,

That part of snow melt that reaches stream channels as runoff.

The process by which small particles suspended in a medium of a different refractive index diffuse a portion of the incident radiation in all directions. In scattering no energy transformation results, only a change in the spatial distribution of the radi ...

That part of an audio-modulated radiosonde consisting of the baroswitch, the sensing elements, the reference elements, and the relay.

Emission or transfer of energy in the form of electromagnetic waves or particles.

A coating of ice, generally clear and smooth. formed by the freezing of supercooled water on a surface.

A halo phenomenon consisting of a horizontal circle passing through the moon, corresponding to the parhelic circle through the sun. Produced by reflection of moonlight from ice crystals.

The water volume within a specified portion of a stream channel.

A type of photoelectric photometer used to measure high-altitude winds on the assumption that stellar scintillation is caused by atmospheric inhomogeneities being carried along by wind near the tropopause level.

Facing away from the wind.

The distance or length of flow of the air past a point during a given interval of time.

A liquid-in-glass or liquid-in-metal thermometer using mercury as the liquid.