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.

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 ...

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 radiosonde equipped to measure temperature only.

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 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.

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.

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.

The difference between the true value of some quantity and its observed value. Every observation is subject to certain errors. Systematic errors affect the whole of a series of observations in nearly the same way. For example, the scale of an instrument m ...

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

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

Any soft, gentle breeze.

A polariscope consisting of a specially constructed double plate polarizer and a tourmaline plate analyzer. Polarized light passing through the instrument is indicated by the presence of parallel colored fringes, while unpolarized light results in a unifo ...

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

Binary Coded Decimal. A coding system in which each decimal digit from 0 to 9 is represented by a 4-digit binary number.