The audio-frequency signal transmitted by the Diamond-Hinman radiosonde when the baroswitch pen passes each fifth contact of the commutator up to a number determined by the design of the commutator. It then signals every contact except the fifth, which is ...

The measuring, transmitting, receiving, and indicating apparatus for obtaining the value of a quantity at a distance.

Of or pertaining to rain.

In a system of moist air, the dimensionless ratio of the mass of water vapor to the mass of dry air. For many purposes, the mixing ratio may be approximated by the specific humidity.

A general term for instruments designed to measure the amount of cloudiness.

A wooden enclosure about sixteen feet square and eight feet high with a precipitation gauge at its center. The function of the fence is to minimize eddies around the gauge and thus insure a catch that is representative of the actual rainfall or snowfall.

A general term to designate apparatus designed to observe the details of weather during thunderstorms.

An instrument consisting of a series of graduated cylinders possessing selective collection efficiencies. It is used for the measurement of quantities relating to the size distribution of cloud droplets.

Temperarure at which a liquid solidifies under any given set of conditions. It may or may not be the same as the melting point or the more rigidly defined true freezing point or (for water) ice point.

A unit of pressure used principally in oceanography. One decibar (10' dynes/cm2) equals 0.1 bar. In the ocean, hydrostatic pressure in decibars very nearly equals the corresponding depth in meters.

A general term for atmospheric water in any of its forms, i.e. clouds, fog, hail, ice crystals, rain.

A magnetometer of the electromagnetic type which is used to measure the horizontal intensity of the earth's magnetic field.

See gain.

Abbreviation for precipitation-evaporation quotient.

A modification of the dew cell used in radiosonde equipment.

An anemometer utilizing the principle that the pitch of the aeolian tones generated by air moving past an obstacle is a function of the speed of the air. Largely a curiosity and has been put to no practical application in modem meteorology.

A pressure-operated switching device used in a radiosonde. In operation, the expansion of an aneroid capsule causes an electrical contact to scan a radiosonde commutator composed of conductors separated by insulators.

force wind-Wind with a speed above 64 knots (73 mph); Beaufort scale numbers 12 through 17.

General name for a type of instrument which measures the inclination of the wind to the horizontal plane. See bivane.

Same as precipitation-evaporation ratio.