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

The average temperature of the air as indicated by a properly exposed thermometer for a given time period, usually a day, a month, or a year.

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.

An aneroid barometer arranged so that the deflection of the aneroid capsule actuates a pen which graphs a record on a rotating drum. Sometimes called aneroidograph.

A clock-driven device for recording the time of occurrence of an event or the time interval between the occurrence of events.

A unit of luminous intensity of a light source.

The height at which the maximum wind speed occurs, determined in a winds-aloft observation.

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

A system of physical units based on the use of the centimeter, gram. and the second as elementary quantities of length. mass. and time.

Operation mode of a communication circuit in which one end can only transmit and the other end can only receive.

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, ...

As used by the U.S. Army Corps of Engineers, the departure (in

A measure of luminous flux remaining in a light beam after it has passed through a specified distance of the atmosphere.

A special type of radar target, usually a comer reflector, tied beneath a free balloon and designed to be an efficient reflector of radio energy.

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

See instrument error, observational error. random error, standard error, systematic error.

Any conventional barometer fitted with an extended scale so that atmospheric pressure measurements may be made at both high and low altitudes.

In radiometry, a measure of the intrinsic radiant intensity emitted by a radiator in a given direction.

The frequency of a carrier wave.

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.