An evaluation of upper air temperature, pressure, and humidity from radio signals received from a balloon- borne radiosonde.

Frozen or partly frozen rain.

Tables prepared from the psychrometric formula and used to obtain vapor pressure, relative humidity, and dew point from values of wet-bulb and dry-bulb temperatures.

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.

Any device or instrument for measuring salinity, especially one based on electrical conductivity methods.

The group of bits which a computer processes as a unit; often, 8 bits.

A unit of mass numerically equal to the molecular weight of the substance. The gram-mote or gram-molecule is the mass in grams numerically equal to the molecular weight, i.e. a gram-mole of oxygen is 32 grams.

See instrument error, observational error. random error, standard error, systematic error.

A small anemometer with flat vanes which indicates the number of linear feet or meters of air which have passed the instrument during its exposure.

Electromagnetic radiation of very short wavelength. lying within the wavelength interval of 0.1 to 1.5 angstroms (between gamma rays and ultraviolet radiation). X-rays penetrate various thicknesses of all solids, and they act on photographic plates in the ...

A precipitation gauge consisting of a receiver in the shape of a funnel which empties into a bucket mounted upon a weighing mechanism. The weight of the catch is recorded as inches of precipitation.

See radiation shield.

The record or trace made by a microbarograph.

General term for any device that measures precipitation: principally a rain gauge or snow gauge.

A rain gauge capable of measuring very small amounts of precipitation. Also called micropluviometer, trace recorder.

The standard deviation (positive square-root of the variation) of the errors associated with physical measurements of an unknown quantity, or statistical estimates of an unknown parameter or of a random variable.

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.

The meteorological visual range, which can be estimated from the average extinction coefficient using the Koschmieder equation.

See aneroid capsule.

An instrument which measures combined direct solar radiation and diffuse sky radiation. See pyrheliometer, Robitzsch actinograph. solarimeter. See also albedometer.