Same as photometer.

A cup anemometer with its shaft mechanically coupled to a magneto.

An instrument that automatically records pressure and temperature.

An apparatus, used in studying soil temperatures, for measuring the total supply of heat during a given period.

See foehn.

A radiosonde which is dropped by parachute from an aircraft for the purpose of obtaining soundings of the atmosphere below.

An instrument for measuring the intensity of light or the relative intensity of a pair of lights. Also called an illuminometer. If the instrument is designed to measure the intensity of light as a function of wavelength, it is called a spectrophotometer. ...

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.

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.

A recording weight barometer.

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

Board that holds graph paper on which is plotted information obtained from a pilot-balloon observation.

Transistor-Transistor Logic.

A flower-like diagram indicating the relative frequencies of different wind directions for a given station and period of time.

A systematic observational error due to the characteristics of the observer. The uncertainty in a reading made by an observer may be acertained by a statistical analysis of his or her readings.

A systematic summary of the terms (inflow, outflow, and storage) of the storage equation as applied to the computation of soil-moisture changes, ground-water changes, etc. An evaluation of the hydrologic balance of an area. Also called basin accounting, w ...

The mass density of a parcel of air expressed in units of mass per volume.

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 wave disturbance in airflow due to some barrier in the flow. i.e. a hill or mountain.

Any source of radiant energy, especially electromagnetic energy.