See photometer.

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.

See stage.

A line drawn through all points on a map having the same amount of cloudiness.

A device for computing certain psychrometric data, usually the dew point and the relative humidity, from known values of the dry-bulb and wet-bulb temperatures and the atmospheric pressure. One type is the circular slide-rule form and, like the psychromet ...

A graphical representation of stage or discharge at a point on a stream as a function of time.

An instrument for measuring snow hardness in terms of the resistance of snow to the pressure exerted by a disk attached to a spring-loaded rod, a gauge calibrated in pounds per square inch registers the amount of resistance. See Canadian hardness gauge.

A systematic summary of the terms (inflow, outflow, and storage) of the storage equation as applied to the computation of soil-moisture changes, ground-water changes, etc. An evaluation of the hydrologic balance of an area. Also called basin accounting, w ...

A type of modulation in which the frequency of a continuous radio carrier wave is varied in accordance with the properties of a second (modulating) wave.

The point (physical and/or electrical) where two distinct data processing elements meet.

Wind with a speed between 28 and 33 knots (32 and 38 mph); Beaufort scale number 7.

A magnetometer of the electromagnetic type which is used to measure the horizontal intensity of the earth's magnetic field.

A precipitation amount of less than 0.005 inches. Also, the record made by any self-registering instrument.

A rotation anemometer which has a horizontal axis upon which helicoidal shaped vanes are mounted. See windmill anemometer.

A mercury barometer in which the tube is U-shaped and the upper and lower mercury surfaces have the same diameter.

Same as precipitation- effectiveness index.

A warm, dry wind on the lee side of a mountain range, the warmth and dryness due to adiabatic compression upon descent.

A unit of luminance or brightness equal to 1/d candles per foot'.

A type of cistern barometer in which the level of mercury in the cistern is adjusted to the zero point of the scale before each reading.

A radiosonde which is dropped by parachute from an aircraft for the purpose of obtaining soundings of the atmosphere below.