A recording anemoclinometer.

Temperature of equilibrium between the liquid and vapor phases of a substance at a given pressure.

In radiometry, a measure of the intrinsic radiant intensity emitted by a radiator in a given direction.

A precipitation gauge consisting of a receiver in the shape of a funnel which empties into a bucket mounted upon a weighing mechanism. The weight of the catch is recorded as inches of precipitation.

The total area drained by a river and its tributaries. Same as watershed.

Automated Surface Observing System. A network of instrumented weather stations deployed primarily by the National Weather Service to make weather observations without operator involvement.

A sunshine recorder of the type in which the time scale is supplied by the motion of the sun. It consists essentially of a spherical lens which bums an image of the sun upon a specialty prepared card.

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 modification of the dew cell used in radiosonde equipment.

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

A definite portion of a stream channel, commonly taken between two gauging stations, but may be taken between any two specified points.

An instrument for measuring the frost point of the atmosphere.

A graphical aid used in fire weather forecasting to calculate the degree of forest-fire danger (or burning index). Commonly in the form of a circular slide rule, the firedanger meter relates numerical indices of (a) the seasonal stage of foliage, (b) the ...

Same as geostrophic wind level.

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

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.

Abbreviation for precipitation-evaporation ratio.

A forecast of the expected stage or discharge at a specified time, or of the total volume of flow within a specified Interval of time, at one or more points along a stream.

A device which automatically records the water equivalent of snow on a given surface as a function of time. A small sample of a radioactive salt is placed in the ground in a shielded collimator which directs a beam of radioactive particles upwards. A Geig ...