A modification of the dew cell used in radiosonde equipment.

An instrument used to measure the water vapor content of the air.

An instrument for the measurement of the radon content of the atmosphere.

Any one of six gases, helium, neon, argon, krypton, xenon, and radon, all of whose shells of planetary electrons contain stable numbers of electrons such that the atoms are chemically inactive.

A measure of the degree to which the weather or climate of a region is favorable to the process of evaporation. Usually considered to be the rate of evaporation. under existing atmospheric conditions, from a surface of water which is chemically pure and h ...

A curve showing the variation of temperature with height in the free air. See lapse rate.

A hypothetical temperature characterized by a complete absence of heat and defined as 0 K, -273.15 C, or -459.67 F.

Snow shower, particularly of a very light and brief nature.

An old nautical term for mercury barometer.

Extended Binary Coded Decimal Interchange Code. A standard code used to represent data using 8 bits per character.

The total amount of water transferred to the atmosphere by evapotranspiration.

Precipitation composed of balls or irregular lumps of ice with diameters between 5 and 50 mm.

See hydrologic accounting.

The elevation of the water surface in a stream as measured by a river gauge with reference to some arbitrarily selected zero datum.

The amount of precipitation falling in one day, or other specified period, that is likely to be equalled or exceeded in any given place only once in a century. That is, a precipitation amount that has a return period of 100 years.

A buoyant balloon rising freely in the atmosphere, as opposed to a captive balloon.

Precipitation from a cumuliform cloud. Characterized by the suddenness of beginning and ending, by the rapid change in intensity, and usually by a rapid change in the condition of the sky. The solid or liquid water particles are usually bigger than the co ...

A clock-driven instrument mounting which automatically and continuously points in the direction of the sun. It is used with a pyrheliometera,hen continuous direct solar radiation measurements are required.

The audio-frequency signal transmitted by the Diamond-Hinman radiosonde when the baroswitch pen passes each fifteenth contact of the commutator, up to a number determined by the design of the commutator, and each fifth contact thereafter. This signal is t ...

The rate of decrease of temperature with height when unsaturated air is lifted adiabatically (without exchange of heat with its surroundings). The decrease is due to expansion as the air is lifted to a lower pressure.