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 ...

An instrument which indicates the presence of dust particles in the atmosphere. Also spelled coniscope.

The process by which events in the real world are translated into machine-readable signals.

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

The sum of solar and terrestrial radiation.

The correctable part of the inaccuracy of an instrument.

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 ...

Apparatus in which radar techniques are used to determine the range, elevation, and azimuth of a balloonborne target, to computer upper-air wind data. It is a type of rawin system.

An instrument used for the measurement of the reflecting, power (the albedo) of a surface. A pyranometer adapted for the measurement of radiation reflected from the earth's surface is sometimes employed as an albedometer.

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.

The visibility along an identified runway, determined from a specified point on the runway with the observer facing in the same direction as a pilot using the runway. Compare to runway visible range.

A form of data transmission in which the bits of each character are sent one at a time along a single communication path. Compare to parallel data transmission.

See gust and peak gust.

The ratio of the amount of electromagnetic radiation reflected by a body to the amount incipient upon it, commonly expressed as a percentage. The albedo is to be distinguished from the reflectivity, which refers to one specific wavelength.

(1) The ratio of the speeds of a chemical reaction at two temperatures differing by 10

The humidity transducinu element in a Diamond-Hinman radiosonde. Also called electrolytic strip.

A type of modulation in which the frequency of a continuous radio carrier wave is varied in accordance with the properties of a second (modulating) wave.

The range of operating conditions of a device within which operating influences are negligible. The range is usually narrow. Reference operating conditions are the conditions under which reference performance is stated and the base from which the values o ...

Automated Weather Observing Station. A self-contained weather station designed to make aviation weather observations without operator involvement.

Ice crystal deposits formed by sublimation (conversion of water vapor directly to ice) when temperature and dew point are below freezing.