A number of quantity defining a limit that errors will not exceed when a device is used under specified operating conditions. Accuracy rating can be expressed in a number of forms, i.e. in terms of the measured variable (+/- 1 C), percent of span (+/-0.5% ...

Any device or instrument for measuring salinity, especially one based on electrical conductivity methods.

An old nautical term for mercury barometer.

See calorie.

The temperature at which a solid substance undergoes fusion, i.e. melts, changes from solid to liquid form. All substances have their characteristic melting points. For very pure substances the temperature range over which the process of fusion occurs is ...

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

Companion to the wet-bulb thermometer in a psychrometer. Used to measure ambient air temperature.

National Centers for Environmental Prediction. Central computer and communications facility of the National Weather Service; located in Washington, DC.

A method of winds aloft observation accomplished by tracking a balloon-borne radar target or radiosonde with either radar or a radio theodolite.

A relatively small-scale, upward moving current of air.

The temperature to which a sample of air must be cooled, while the mixing ratio and barometric pressure remain constant, in order to attain saturation by water vapor. When this temperature is below O

Same as dropsonde.

A wind blowing in the same direction as the heading of a moving object. thus assisting the object's intended progress. The opposite of a head wind.

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

A scale with the ice point at zero degrees and the boiling point of water at 80 degrees, with pressure of one atmosphere.

A system in which radar techniques are used to determine the range, elevation, and azimuth of a radar target carried a!oft by a radiosonde, so that wind data may be obtained along with the other meteorological data.

A cover which fits over a large inflated balloon to facilitate handling in high or gusty winds.

Same as atmospheric pressure.

Precipitation composed of balls or irregular lumps of ice with diameters between 5 and 50 mm.

Negative Vorticity Advection.