Difference between the temperatures of the dry-bulb and the wet-bulb thermometers of a psychrometer.

The volume of water required to cover one acre to a depth of one foot: 43,560 cubic feet.

pattern barometer-Mercurial barometer with a fixed scale and cistern and which therefore requires only one adjustment before each reading.

A unit of luminous intensity of a light source.

Occupational Safety and Health Administration. A regulatory office of the U.S. Department of Labor.

A photometer which measures the intensity of radiation as a function of the frequency (or wavelength) of the radiation.

A line of equal or constant pressure.

See gain.

See hurricane beacon.

Interational thermometric scale on which the freezing point of water equals 0

Line drawn through geographical points recording equal amounts of precipitation during a given time period or for a particular storm.

A graphical aid used in fire weather forecasting to calculate the degree of forest-fire danger (or burning index). Commonly in the form of a circular slide rule, the firedanger meter relates numerical indices of (a) the seasonal stage of foliage, (b) the ...

A method of upper air observation consisting of an evaluation of the wind speed and direction, temperature, pressure, and humidity aloft by means of a balloon-borne radiosonde tracked by radar or a radio theodolite.

The water portion of the earth as distinguished from the solid part, called the lithosphere, and from the gaseous outer envelope, called the atmosphere.

Overflowing by water of the normal confines of a stream or other body of water, or accumulation of water by drainage over areas which are not normally submerged.

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

Generic term for rapid variations in apparent position, brightness, or color of a distant luminous. object viewed through the atmosphere.

One of several constant-pressure levels in the atmosphere for which a complete evaluation of data derived from upper air observations is required.

A general term for atmospheric water in any of its forms, i.e. clouds, fog, hail, ice crystals, rain.

Same as water year.