A nephoscope in which the motion of the cloud is observed by its reflection in a mirror.

Water vapor content of the air. See absolute humidity, dew point, mixing ratio, relative humidity, specific humidity.

Instrument which measures and records the amount of evaporation over time.

A type of pressure-tube anemometer, named after the inventor.

The direction toward which the wind is blowing; with the wind.

For a given locality and month, an empirical expression devised for the purpose of classifying climates numerically on the basis of precipitation and evaporation.

A protocol similar to RS232 which permits data interchange on multidrop networks of up to 32 nodes using a single twisted pair cable. In order for this protocol to be used, each device on a network must have some level of intelligence in order establish o ...

An instrument which measures the instantaneous rate at which rain is falling on a given surface. Also called a rate-of-rainfall gauge.

The elevation of the water surface in a stream as measured by a river gauge with reference to some arbitrarily selected zero datum.

An instrument which measures the transmissivity of the atmosphere between two points for the determination of visual range.

An instrument used to measure the water vapor content of the air.

An Instrument used to determine dew point.

An instrument used to measure the amount of dew formed on a given surface.

A system of physical units based upon the use of the meter, the metric ton (106 grams), and the second as elementary quantities of length, mass, and time, respectively.

The audio-frequency signal transmitted by the Diamond-Hinman radiosonde when the baroswitch pen passes each fifth contact of the commutator up to a number determined by the design of the commutator. It then signals every contact except the fifth, which is ...

The closeness of agreement among a number of consecutive output values measuring the same input value under the same operating conditions, approaching from the same direction. Usually measured as nonrepeatability but expressed as repeatability, a percenta ...

The flux of visible radiation, so weighted as to account for the manner in which the response of the human eye varies with the Wavelength of radiation. The basic unit for luminous flux is the lumen,

Same as aneroid barometer. Holostelic means wholly made of solids, while aneroid means devoid of liquid.

Transistor-Transistor Logic.

Technically, the temperature registered by the dry-bulb thermometer of a psychrometer. However, it is identical with the temperature of the air and may also be used in that sense.