In radiometry, a measure of the intrinsic radiant intensity emitted by a radiator in a given direction.

Abbreviation for the pressure, temperature, and humidity data obtained by a radiosonde observation.

See gain.

Abbreviation for precipitation-evaporation quotient.

The unit of acceleration in the centimeter-gram-second system of units, equal to one cm per sec2. Commonly used in gravimetry.

United Kingdom forecast model. (Available via AccuWeather.com Professional.)

A radar which is used to obtain the azimuth elevation, and slant range of an airborne target.

A thermometer designed for use in measuring the temperature of sea water. One form consists of a mercury-in-glass thermometer protected by a perforated metal case. Another form consists of a mercury-in-glass thermometer surrounded by a metal case which fo ...

An absolute temperature scale with the ice point of pure water defined as 273.16 K. The size of the degree is the same as on the Celsius scale, and the zero point is absolute zero.

A method of winds aloft observation essentially the same as a pilot balloon observation except the height data is derived from the radiosonde observation rather than from assumed ascension rates.

A radiosonde equipped to measure temperature only.

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

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.

The energy of any type of electromagnetic radiation. Also called radiation.

Name applied to a class of instruments which measure the liquid content of the atmosphere.

Generally, a measure of the departure of the mean daily temperature from a given standard, one degree day for each degree (

An atmospheric phenomenon, other than clouds, which obscures a portion of the sky from the point of observation. Also called obscuration.

Any soft, gentle breeze.

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 ...

The source of illumination for an antenna reflector. Also called antenna feed.