The inaccuracy that the manufacturer permits when the unit is calibrated in the factory.

The intensity (flux per unit solid angle) of visible radiation weighted to take into account the variable response of the human eye as a function of the wavelength of light. Usually expressed in candles.

A sudden brief increase in the speed of the wind, followed by a lull or slackening. Compare to peak gust.

An instrument for measuring the difference between incoming and outgoing terrestrial radiation.

A rotation anemometer in which the axis of rotation is horizontal. The instrument has either flat vanes (as in the air meter) or helicoidal vanes (as in the propeller anemometer). The relation between wind speed and angular rotation is almost linear.

bucket rain gauge-A rain gauge where the precipitation collected by the receiver empties into one side of a chamber which is partioned transversely at its center and is balanced bistably upon a horizontal axis. When a predetermined amount of water has bee ...

The scientific study of the waters of the earth, especially with relation to the effects of precipitation and evaporation upon the occurrence and character of water in streams, lakes, and on or below the land surface. In terms of the hydrologic cycle, the ...

A photometric unit of illuminance or illumination equal to one lumen per square centimeter.

Same as rain gauge.

Growth of a cloud or precipitation particle by the collision and union of a frozen particle with a super-cooled water drop.

Thermometer used for measuring the lowest temperature attained during a given interval of time, for example, a day.

The transducer's output when the maximum sensed value is applied to the transducer's input. For example, the F.S. output of a 4-20 mA transmitter is 20 mA, whereas its span is only 16mA.

Same as dew-point hygrometer.

Operation mode of a communication circuit in which one end can only transmit and the other end can only receive.

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

Interational thermometric scale on which the freezing point of water equals 0

Operation mode of a communication circuit in which each end can simultaneously transmit and receive.

Electromagnetic radiation lying within the wavelength interval to which the human eye is sensitive, the spectral interval from approximately 0.4 to 0.7 microns (4000 to 7000 angstroms). Bounded on the short-wavelength end by ultraviolet radiation and on t ...

A special type of radar target, usually a comer reflector, tied beneath a free balloon and designed to be an efficient reflector of radio energy.

The process whereby a position on the scale of an instrument is identified with the magnitude of the signal (or input force) actuating the instrument.