Value of soil moisture, expressed as a percentage of the mass of dry soil, below which a plant living in the soil dies by wilting.

A set of electrical conductors, often on a backplane, that carry data and power signals among the various components of a computer.

A line drawn through geographical points where a given seasonal biological event occurs on the same date.

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

The total luminous flux received on a unit area of a given real or imaginary surface, expressed in such units as the foot-candle, lux, or phot.

A unit of distance equal to 5280 feet. It is sometimes referred to as a land mile.

Sustained winds greater than or equal to 40 mph or gust greater than or equal to 58 mph.

Anemometer which generates an electrical contact output with a frequency proportional to wind speed.

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

An instrument used for measuring the specific gravity of a liquid.

The intensity (flux per unit solid angle) of visible radiation weighted to take into account the variable response of the human eye as a function of the wavelength of light. Usually expressed in candles.

A thermopile used in some types of radiation instruments. See solarimeter.

Contraction for radiosonde observation.

An instrument for collecting liquid water from the atmosphere.

Upwarddirected solar radiation, reflected by the earth's surface and the atmosphere.

Wind with a speed between 56 and 63 knots (64 and 72 mph); Beaufort scale number 11.

An absolute instrument developed by K. Angstrom for the measurement of direct solar radiation. The radiation receiver station consists of two identical manganin strips whose temperatures are measured by attached thermocouples. One of the strips is shaded, ...

The ratios, to the mean wind speed, of the average magnitudes of the component fluctuations of the wind along three mutually perpendicular axes.

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

The algebraic difference between the upper and lower limits of the measuring range of an instrument, i.e. a thermometer with a range of -35 to 50