bucket rain gauge-A rain gauge where the precipitation collected by the receiver empties into one side of a chamber which is partioned transversely at its center and is balanced bistably upon a horizontal axis. When a predetermined amount of water has bee ...

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 ...

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

A type of atmometer. It is a pan used in the measurement of the evaporation of water into the atmosphere. The NWS Class A pan is a cylindrical container 48 inches in diameter and 10 inches deep.

Solar and terrestrial radiation directed downwards (towards the earth's surface); incoming radiation.

Wind with a speed between 17 and 21 knots (19 and 24 mph); Beaufort scale number 5.

Overflowing by water of the normal confines of a stream or other body of water, or accumulation of water by drainage over areas which are not normally submerged.

For a given locality and month, an empirical expression devised for the purpose of classifying climates numerically on the basis of precipitation and evaporation.

Particle on which the freezing of water occurs.

For a given location, a measure of the long-range effectiveness of precipitation in promoting plant growth. Also called precipitation-evaporation index.

A class of rain gauge in which the level of the collected rain water is measured by the position of a float resting on the surface of the water.

Same as dew-point hygrometer.

A term used to describe a sensor (or sensors), the associated transducer(s), and the data readout or recording device.

A fixed support for mounting maximum and minimum thermometers of the liquid-in-glass type. The support holds the thermometers at the correct operating attitude and also permits their rotation for resetting when desired.

Radiation coming from the solid angle of the sun's disc, as opposed to diffuse sky radiation, effective terrestrial radiation, or radiation from any other source. Direct solar radiation is measured by pyrheliometers.

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.

An anemometer in which the sensor rotation is transmitted to a mechanical counter which directly integrates the air movement past the sensor. Used to determine total air passage (wind run). Average wind speed can be calculated from the difference between ...

Instrument for measuring the mean intensity of glo global solar radiation (direct and diffuse) near the earth's surface in a specified time interval.

Same as Aeolian.

A device that allows a terminal or computer at one location to communicate with a terminal or computer at a distant location via wire or phone lines.