A recording magnetometer.

An instrument for determining the direction from which radio waves approach a receiver. It may consist of a manually operated direction indicator, or it may use a servo system to position the antenna automatically in the direction of the incident waves. T ...

Old snow that has become granular and compacted as a result of melting and refreezing.

An estimate of the temperature of an incandescent body, determined by observing the wavelength at which it is emitting with peak intensity (its color) and using that wavelength in Wien's law.

A hygrometer which uses a transducing element whose electrical properties are a function of atmospheric water vapor content. The humidity strip and carbon-film hygrometer element are examples of such a transducer.

The total amount of water transferred to the atmosphere by evapotranspiration.

A weakly colored lunar halo identical in form and optical origin to the solar parhelion.

Clouds which cover between 6/10 and 9/10 of the sky. See Sky Terminology.

Temperarure at which a liquid solidifies under any given set of conditions. It may or may not be the same as the melting point or the more rigidly defined true freezing point or (for water) ice point.

A description or explanation of the manner in which the height of the ceiling is determined, i.e. aircraft ceiling, balloon ceiling. estimated ceiling, indefinite ceiling, measured ceiling, precipitation ceiling.

Read Only Memory. A memory that cannot be altered in normal use of a computer, Usually used to store information permanently, such as firmware programs.

Literally "not wet", containing no liquid.

The energy of any type of electromagnetic radiation. Also called radiation.

An instrument for measuring differences in electric potential.

Same as marine rainbow.

An instrument for measuring radiant energy. See actinometer, Dines radiometer, photometer, Tulipian radiometer.

Any and all forms of water particles, liquid or solid, that fall from the atmosphere and reach the ground.

A motorlike device containing a rotor and a stator and capable of converting an angular position into an electrical signal, or an electrical signal into an angular position. When several synchros are correctly connected, all of the rotors will align thems ...

A pointed device which indicates the amount of resistance encountered when it is forced into a material such as snow or soil. See ram penetrometer.

An instrument, dropped from high attitude and carried by a stable parachute. used to measure the vertical component of turbulence aloft.