Same as precipitation- effectiveness index.

Same as river gauge.

A liquid-in-glass thermometer which uses an organic substance such as alcohol as the thermometer liquid. This type of thermometer has a low freezing point and a high coefficient of expansion. It is less accurate, however, than a mercury thermometer.

Any wind blowing down an incline. If warm, it is a foehn. If cold, it may be a fall wind or a gravity wind.

The lowest value of a measured quality at which a sensor meets its accuracy specification.

An instrument which measures evaporation by measuring the loss of water from a burette reservoir through a ceramic disc.

The difference between temperature measurements taken at two significant levels above the ground. Temperatures at 10 and 40 meters are commonly used.

See stage.

Snow shower, particularly of a very light and brief nature.

A rain gauge which is placed under trees or foliage to determine the rainfall in that location. By comparing this catch with that from a rain gauge set in the open. the amount of rainfall which has been intercepted by foliage can be determined.

A hypothetical, ideal body which absorbs completely all incident radiation. independent of wavelength and direction. No actual substance behaves as a true black body, although platinum black and other soots rather closely approximate this ideal. However, ...

Thermometer used for measuring the lowest temperature attained during a given interval of time, for example, a day.

Barometer in which pressure is determined by balancing air pressure against the weight of a column of mercury in an evacuated glass tube.

The humidity transducinu element in a Diamond-Hinman radiosonde. Also called electrolytic strip.

An absolute pyhrliometer, developed by C.G. Abbott, in which the radiation-sensing element is a blackened water-calorimeter.

An instrument which automatically determines the size distribution of raindrops.

To free something from the binding action of ice by warming it to a temperature above the melting point of ice. Also, a warm spell when ice and snow melt.

A relatively small-scale, downward moving current of air.

An instrument used for the determination of the electrical conductivity of the atmosphere.

A current meter consisting of six conical cups, mounted around a vertical axis, which rotate and generate a signal with each rotation. Tail vanes and a heavy weight stabilize the instrument.