That temperature at which, in a specified latitude, the reading of a particular barometer requires no temperature or latitude correction.

A type of electrical thermometer consisting of two thermocouples which are series-connected with a potentiometer and a constant-temperature bath. One couple, called the reference junction, is placed in a constant-temperature bath, while the other is used ...

The probability distribution of random errors, typically a normal distribution with a zero mean.

The addition of one or more redundant bits to information to verify its accuracy.

A small, moveable graduated scale adjacent and parallel to the main scale of an instrument. It provides a means for interpolating between the graduations of the main scale.

Navy Operational Global Atmospheric Prediction System. A global meteorological model operated by the Department of Defense.

Programs or instructions which are stored in readonly memory.

Small particle on which water vapor condenses.

A device which automatically records the water equivalent of snow on a given surface as a function of time. A small sample of a radioactive salt is placed in the ground in a shielded collimator which directs a beam of radioactive particles upwards. A Geig ...

A pyranometer developed by M. Robitzsch. Its design utilizes three bimetallic strips which are exposed horizontally at the center of a hemispherical glass bowl. The outer strips are white reflectors and the center strip is a blackened absorber. The bimeta ...

An instrument which measures the spectral distribution of the intensity of direct solar radiation.

Same as wave pole.

A rainbow formed by light rays which have been reflected from an extended water surface. Not to be confused with a reflected rainbow whose image may be seen in a still body of water. The center of a reflection rainbow is at the same elevation as the sun b ...

An instrument for measuring radiant energy. See actinometer, Dines radiometer, photometer, Tulipian radiometer.

See approximate absolute temperature scale, Celsius temperature scale, centigrade temperature scale, Fahrenheit temperature scale, Kelvin temperature scale, Rankine temperature scale, Reaumur temperature scale,

A transducer for converting thermal energy directly into electrical energy. It is composed of pairs of thermocouples which are connected either in series or in parallel. Thermopiles are used in thermoelectric radiation instruments when the output of a sin ...

A measure of the intensity of gusts given by the ratio of the total range of wind speed between gusts and the intermediate periods of lighter wind to the mean wind speed, averaged over both gusts and lulls.

National Centers for Environmental Prediction. Central computer and communications facility of the National Weather Service; located in Washington, DC.

A balloon-borne instrument for the simultaneous measurement and transmission of meteorological data. It includes transducers for the measurement of pressure, temperature, and humidity; a modulator for the conversion of the output of the transducers to a q ...

Same as humidity strip.