A hypothetical body which absorbs some constant fraction, between zero and one, of all electromagnetic radiation incident upon it, which fraction is the absorptivity and is independent of wavelength. Compare to black body, white body.

A line of equal or constant temperature.

Not a linear function of the relevant variables.

in folklore, a name for fire.

See constant-level balloon.

The atmospheric pressure computed using station elevation as the reference datum level. Station pressure is usually the base value from which sea level pressure and altimeter setting are determined.

The audio-frequency signal transmitted by the Diamond-Hinman radiosonde when the baroswitch pen passes each fifteenth contact of the commutator, up to a number determined by the design of the commutator, and each fifth contact thereafter. This signal is t ...

Liquid water at temperatures colder than freezing.

Complementary Metal-Oxide Semiconductor. A method of making silicon chips that results in low power consumption by the circuits.

An aneroid barograph designed to record atmospheric pressure variations of very small magnitude.

Same as fogbow.

A thermometer with a muslin-covered bulb which is moistened. used to measure wet-bulb temperature.

A local variation of the wind vector or any of its components in a given direction.

Precipitation composed of liquid water drops more than 0.5 mm in diameter, failing in relatively straight, but not necessarily vertical, paths. Compare to drizzle.

Downward scattered and reflected solar radiation, coming from the whole hemisphere with the exception of the solid angle of the sun's disc on a surface perpendicular to the axis of this cone.

A pointed device which indicates the amount of resistance encountered when it is forced into a material such as snow or soil. See ram penetrometer.

A strong wind characterized by a sudden onset, a duration on the order of minutes, and a rather sudden decrease in speed.

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

Anemometer which measures wind speed by measuring the degree of cooling of a metal film heated by an electric current. A type of cooling-power anemometer.

A unit of distance equal to 5280 feet. It is sometimes referred to as a land mile.