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

A temperature telemeter.

An instrument used for measuring the specific gravity of a liquid.

A method of streamflow routing which assumes that storage is a linear function of the weighted flow in the reach and is adaptable to a simple mathematical solution.

Diffuse solar radiation which has the same intensity in all directions.

A direct-vision nephoscope which is constructed in the following manner: a comb consisting of a crosspiece containing equispaced vertical rods is attached to one end of a column eight to ten feet long and is supported on a mounting that is free to rotate ...

Abbreviation for radio frequency.

A pressure tube anemometer, consisting of a pitot tube mounted on the windward end of a wind vane and a suitable manometer to measure the developed pressure and calibrated in units of wind.

Thermometer used for measuring the lowest temperature attained during a given interval of time, for example, a day.

An instrument for measuring the ultraviolet in solar and sky radiation.

A hydrometeor consisting of a visible aggregate of minute water droplets suspended in the atmosphere near the earth's surface. Fog differs from cloud only in that the base of fog is at the earth's surface while clouds are above the surface.

A large plastic constant-level balloon for duration flying (in excess of 24 hours) at altitudes above 40,000 feet, used for the determination of wind fields and the measurement of upper atmospheric parameters.

A recording anemometer.

A colorless and odorless gaseous element. The lightest and apparently the most abundant chemical element in the universe. However, it is found only in trace quantities in the observable portion of our atmosphere, only about 0.00005 percent by volume of dr ...

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

A numbering system using a base number of 2 and having only two digits: 0 and 1. The fundamental system of representing information with electrical pulses.

The portion of the strearnflow during any month or year derived from precipitation in previous months or years.

Name given to the unit of pressure in the International System of Units (SI). Equal to 1 newton/meter2 or 0.01 millibar.

The actual lifting force of an inflated balloon, usually expressed in grams.

A hygrometer in which the rotation of the hygrometric element is a function of humidity.