A semiconductor which exhibits rapid and extremely large changes in resistance for relatively small changes in temperature.

Same as rain-intensity gauge.

The process by which one object becomes adhered to another by the binding action of ice.

A type of wind vane having a split or V-shaped tail. The apex orients itself to the direction of the wind.

The correctable part of the inaccuracy of an instrument.

The succession of stages through which water passes on the ground and in the atmosphere: evaporation from land or bodies of water, condensation to form clouds, precipitation, accumulation in the soil or in bodies of water, and re-evaporation.

The temperature registered by a thermometer with its bulb at the level of the tops of the grass blades in short turf.

The true freezing point of water. The temperature at which a mixture of air-saturated pure water and pure ice may exist in equilibrium at a pressure of one standard atmosphere.

An element that can control current without moving parts, heated filaments, or vacuum gaps.

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

The maximum difference in output for any given input (within the specified range) when the value is approached first with increasing, and then with decreasing, input signals. Caused by energy absorption in the elements of the measuring instrument. Usually ...

The part of a measuring instrument which responds directly to changes in the environment.

A unit of luminous flux. The lumen is equal to the luminous flux radiated into a unit solid angle (steradian) from a small source having a luminous intensity of one candle. An ideal source possessing an intensity of one candle in every direction would rad ...

The lowest value of a measured quality at which a sensor responds. Compare to tracking.

A unit of luminance (or brightness) equal to 1/6 candles per square centimeter.

The total luminous flux received on a unit area of a given real or imaginary surface, expressed in such units as the foot-candle, lux, or phot.

Snow gauge composed of a metal cylinder, closed at one end, used to obtain a sample of snow from which the water is measured after melting.

The process of modifying some characteristic of a wave (the carrier) so that it varies in step with the instantaneous value of another wave (the modulating wave) in order to transmit a message. The modified characteristic may be frequency, phase, and/or a ...

A type of cyanometer. an instrument used to measure the blueness of the sky. The Linke-scale is simply a set of eight cards of different standardized shades of blue. They are evenly numbered 2 to 26. The odd numbers are used by the observer if he or she j ...

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 ...