The actual time during which physical events take place.

Same as instrument shelter.

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

A line drawn through geographical points where a given seasonal biological event occurs on the same date.

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

A temperature scale on which the freezing point of water equals 32

The lowest value of a measured quality at which a sensor responds. Compare to tracking.

A local variation of the wind vector or any of its components in a given direction.

Electromagnetic radiation of shorter wavelength than visible radiation but longer than x-rays, between 0.02 and 0.4 micron (200 and 4000 angstrom).

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

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

An instrument which automatically determines the size distribution of raindrops.

A temperature scale with the ice point at 273 degrees and boiling point of water at 373 degrees. It is intended to approximate the Kelvin temperature scale with sufficient accuracy for many sciences, notably meteorology.

A sounding balloon which, when operationally inflated, resembles an inverted teardrop.

Same as atmospheric pressure.

Abbreviation for radio frequency.

An instrument for measuring temperature by utilizing the variation of the physical properties of substances according to their thermal states. Thermometers may be classified into types according to their construction; deformation thermometer, electrical t ...

Operation mode of a communication circuit in which each end can transmit and receive, but not simultaneously.

A combination cup anemometer and pressure-plate anemometer, consisting of an array of cups about a vertical axis of rotation, the free rotation of which is restricted by a suitable spring arrangement.

A rain gauge which indicates but does not record the amount of precipitation captured.