A type of recording siphon barometer. The mechanically magnified motion of a float resting on the lower mercury surface is used to record atmospheric pressure on a rotating drum.

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

One of several constant-pressure levels in the atmosphere for which a complete evaluation of data derived from upper air observations is required.

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

Defect in the action of an aneroid barometer resulting in a sluggish adjustment of the index toward the correct reading when the barometer is subjected to a large and rapid change in pressure.

That part of an audio-modulated radiosonde consisting of the baroswitch, the sensing elements, the reference elements, and the relay.

A set of electrical conductors, often on a backplane, that carry data and power signals among the various components of a computer.

Same as balloon cover.

See radiosonde commutator.

General name for an instrument which measures the earth's magnetic field intensity.

The record made by a hygrograph.

Instrument used to measure the amount of water evaporated from the soil surface during a given time interval.

A plastic molding component formed by the reaction of phenol and formaldehyde. It can be heavily reinforced or "filled" with glass fibers or other materials. Phenolics are known for their high impact strength, excellent wear characteristics, and dimension ...

A decrease in the central pressure of a pressure system. Usually applied to a low rather than to a high.

An air-launched balloon designed to be released in the eye of a tropical cyclone, float within the eye at predetermined levels, and transmit radio signals for RDF positioning.

A thermodynamic change of state in a system in which there is no transfer of heat or mass across the boundaries of the system. In an adiabatic process, compression always results in warming, expansion in cooling. Compare to diabatic process.

See river basin.

The play or loose motion in an instrument due to the clearance existing between mechanically contacting parts.

The condition of the atmosphere when the amount of water vapor present is the maximum possible at the existing temperature.

A small anemometer with flat vanes which indicates the number of linear feet or meters of air which have passed the instrument during its exposure.