A precipitation gauge consisting of a receiver in the shape of a funnel which empties into a bucket mounted upon a weighing mechanism. The weight of the catch is recorded as inches of precipitation.

A calorimetric radiation instrument of historic interest used for the measurement of outgoing heat radiation from the earth during an interval of time. The time integration is performed by allowing the radiation to fall on an uninsulated vessel containing ...

A measure, proposed by Angstrom, of the precipitation effectiveness of a region.

A measure of the relative power, or of the relative values of two flux densities, especially of sound intensities and radar power densities. The decibel is derived from the less frequently used unit, the bel, named in honor of Alexander Graham Bell.

An apparatus, used in studying soil temperatures, for measuring the total supply of heat during a given period.

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

A type of anemometer in which the rotation of an element serves to measure the wind. Rotation anemometers are divided into two classes; those in which the axis of rotation is horizontal, such as the windmill anemometer, and those in which the axis of rota ...

A component of the wind (often using Cartesian coordinates. i.e. X and Y wind vectors). Also, an arrow representing wind velocity, drawn to point in the direction of the wind and with a length proportional to wind speed.

An instrument for determining the direction from which radio waves approach a receiver. It may consist of a manually operated direction indicator, or it may use a servo system to position the antenna automatically in the direction of the incident waves.

An instrument used to measure the water vapor content of the air.

That stage, on a fixed river gauge, at which overflow of the natural banks of the stream begins to cause damage in any portion of the reach for which the gauge is used as an index.

The distance that an observer can see vertically into a surface-based obscuring phenomenon such as fog, rain, or snow. The distance estimate must be based upon ceiling balloon ascensions or ceiling light projector measurements.

A device which converts energy from one form into another, i.e. an ac generator transducer which converts the mechanical motion of anemometer cups into an electrical signal.

The group of bits which a computer processes as a unit; often, 8 bits.

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.

Wind with a speed between 11 and 16 knots (13 and 18 mph); Beaufort scale number 4.

A device, similar to a phytometer, for measuring transpiration. It consists of a small vessel containing water and sealed so that the only escape of moisture is by transpiration from a leaf, twig, or small plant with its cut end inserted in the water.

Closed, curved, flexible tube of elliptic cross section which is deformed, according to type, by variations of atmosphere spheric pressure or temperature and so provides a measurement of the particular parameter.

A device that combines several separate communications signals into one and outputs them on a single line.

Any sudden and heavy rain, almost always of the shower type.