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.

Same as rain gauge.

A device used to switch electrical current at a selectable setpoint temperature.

A reflecting type telescope with a 45

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.

Very generally, any moving- stream of air. It has no particular technical connotation.

Any quantity, such as force velocity, or acceleration, which has both magnitude and direction at each point in space, as opposed to scalar which has magnitude only. Such a quantity may be represented geometrically by an arrow of length proportional to its ...

A instrument designed to study small fluctuations of some quantity. The microbarograph is an example of a recording pressure variometer.

The process by which events in the real world are translated into machine-readable signals.

A line drawn through geographical points having the same pluvial index.

Operation mode of a communication circuit in which each end can simultaneously transmit and receive.

The difference between the air temperature and the dew-point. Also called dew-point deficit, dew-point depression.

A graphical representation of stage or discharge at a point on a stream as a function of time.

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

In a system of moist air, the dimensionless ratio of the mass of water vapor to the mass of dry air. For many purposes, the mixing ratio may be approximated by the specific humidity.

A modification of the dew cell used in radiosonde equipment.

A radiosonde which transmits the indication of the meteorological sensing elements in the form of a code consisting of combinations of dots and dashes.

A device that allows a terminal or computer at one location to communicate with a terminal or computer at a distant location via wire or phone lines.

Same as atmospheric pressure.

A balloon designed to float at a constant pressure level. This may be accomplished by a pressure valve which controls the release of ballast so as to maintain flight above a selected pressure level until the supply of ballast is exhausted. See Moby Dick b ...