A balloon used to carry a radiosonde aloft, considerably larger than pilot balloons or ceiling balloons.

Same as dew-point hygrometer.

The temperature at which the liquid and solid forms of a substance may exist in equilibrium at a given pressure (usually one standard atmosphere). The true freezing point of water is known as the ice point.

An instrument resulting from the combination of a thermograph and a hygrograph and furnishing, on the same chart, simultaneous time recording of ambient temperature and humidity.

In folklore, a name for rain.

A contact anemometer connected to an electrical circuit which is so arranged that the average wind speed is indicated.

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 ...

Generally, the relative states of inflow, outflow, and storage of moisture over a given area of earth's surface.

An evaporation pan in which the evaporation is measured from water in a pan floating in a larger body of water.

A unit of luminous intensity of a light source.

A hygrometer which includes an arrangement for the time recording of atmospheric humidity.

Pertaining to measurements or devices in which the output varies continuously, i.e. voltage or rotation signals. Compare to digital.

Apparatus using the combined simultaneous action of a bimetallic thermometer and a hair hygrometer to move a needle in front of a divided scale. fts construction permits dew point variations to be indicated approximately.

A river gauge in which a weight suspended on a wire is lowered to the water surface from a bridge or other overhead structure to measure the distance from a point of known elevation to the water surface.

A scale with the ice point at zero degrees and the boiling point of water at 80 degrees, with pressure of one atmosphere.

See Koschmieder's law.

A basic equation in night visual range theory, relating the illuminance of a point source of light to distance and the transmissivity of the atmosphere.

Operation mode of a communication circuit in which each end can transmit and receive, but not simultaneously.

An atmometer consisting of a porous porcelain or ceramic container connected to a calibrated reservoir filled with distilled water. Evaporation is determined by the depletion of water in the reservoir.

In the direction from which the wind is blowing.