The group of bits which a computer processes as a unit; often, 8 bits.

The source of illumination for an antenna reflector. Also called antenna feed.

A thermometer consisting of a clock mechanism the speed of which is a function of temperature.

A type of climatic diagram whose coordinates are some form of temperature vs. a form of humidity or precipitation.

A measure of the relative power, or of the relative values of two flux densities, especially of sound intensities and radar power densities. The decibel is derived from the less frequently used unit, the bel, named in honor of Alexander Graham Bell.

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.

Downward-facing pyranometer used for measuring reflected solar radiation.

Erasable Programmable Read Only Memory. Programable read-only memory which can be erased, usually by ultraviolet light, and re-programmed.

A sunshine recorder of the type in which the time scale is supplied by the motion of the sun. It consists of two opaque metal semi-cylinders mounted with their curved surfaces facing each other. Each of the semi-cylinders has a short narrow slit in its fl ...

A tube designed to measure the rate of flow of fluids. It consists of a tube having a constriction or throat at its midsection. The difference between the pressure measured at the inlet and at the throat is a function of the fluid velocity. Compare to Pit ...

General name for an instrument designed to measure the vertical component of the wind speed. See anemoclinometer.

Winds from the four cardinal points of the compass; that is, north, east, south, and west winds.

A particular pattern of snow sampler having an internal diameter of 1.485 inches so that each inch of water in the sample weighs one ounce.

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

A modification of the dew cell used in radiosonde equipment.

The statement that the viscosity of air is independent of the density of air.

An instrument which measures the instantaneous rate at which rain is falling on a given surface. Also called a rate-of-rainfall gauge.

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

A liquid-in-glass or liquid-in-metal thermometer using mercury as the liquid.

The stage on a fixed river gauge at which it is necessary to begin issuing warnings or river forecasts if adequate precautionary measures are to be taken before flood stage is reached.