The interval between the lower and upper measuring limits of an instrument, i.e. a thermometer with a range of -35 to 50

See gain.

The most common of the principal rainbow phenomena, which appears as an arc of about 42

Name given to the unit of pressure in the International System of Units (SI). Equal to 1 newton/meter2 or 0.01 millibar.

Same as aneroid barometer. Holostelic means wholly made of solids, while aneroid means devoid of liquid.

The closeness of agreement among a number of consecutive output values measuring the same input value under the same operating conditions, approaching from the same direction. Usually measured as nonrepeatability but expressed as repeatability, a percenta ...

The maximum distance, usually horizontally, at which a given object or light source is just visible under particular conditions of transmittance and background luminance.

A thermometer used in aircraft which automatically corrects for adiabatic and frictional temperature rises by imparting a rotary motion to the air passing the thermal sensing element.

A recording weight barometer.

A graphical aid used in the reduction of data from a winds aloft observation.

Rain gauge which registers precipitation that is too light to be registered by ordinary recording of the depth of water from precipitation. Same as ombrometer.

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.

The ratio of the output of an instrument to the input value, i.e. a rain gauge with a sensitivity of 1 tip per 0.01"

The line-of-sight distance between two objects.

A motorlike device containing a rotor and a stator and capable of converting an angular position into an electrical signal, or an electrical signal into an angular position. When several synchros are correctly connected, all of the rotors will align thems ...

A line drawn through geographical points having the same pluvial index.

A measure of the amount of "spin" (or rotation) in the atmosphere.

Pertaining to the action or effect of the wind. Derived from the name of the Greek god of the winds, Aeolus.

The standard deviation of a sufficiently large number of measurements of the same quantity by the same instrument or method. The non-correctable part of the inaccuracy of an instrument, it represents the limit of measurement precision. The uncertainty of ...

meter-An instrument for measuring the transmissivity of the atmosphere; a type of transmissometer. It consists of a constant- intensity collimated light source located at a suitable distance from a photoelectric cell. Variation in the turbidity of the atm ...