The atmospheric pressure computed using station elevation as the reference datum level. Station pressure is usually the base value from which sea level pressure and altimeter setting are determined.

A rainbow seen in the spray of the ocean. It is optically the same phenomenon as the ordinary rainbow.

A recording anemoclinometer.

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.

Any emission of light at temperatures below that required for incandescence.

A thermometer. the sensitive element of which consists of two metal strips which have different coefficients of expansion and are brazed together. The distortions of the system in response to temperature variations are used as a measure of temperature. It ...

Any sudden and heavy rain, almost always of the shower type.

A scale with the ice point at zero degrees and the boiling point of water at 80 degrees, with pressure of one atmosphere.

A systematic summary of the terms (inflow, outflow, and storage) of the storage equation as applied to the computation of soil-moisture changes, ground-water changes, etc. An evaluation of the hydrologic balance of an area. Also called basin accounting, w ...

A hygrometer which determines the amount of precipitable moisture in a given region of the atmosphere by measuring attenuation of radiant energy caused by the absorption bands of water vapor.

A rain gauge which is placed under trees or foliage to determine the rainfall in that location. By comparing this catch with that from a rain gauge set in the open. the amount of rainfall which has been intercepted by foliage can be determined.

A strong wind characterized by a sudden onset, a duration on the order of minutes, and a rather sudden decrease in speed.

A vent used with pressure sensors to reduce the effect of wind on the pressure inlet. It is normally mounted remotely and connected to the sensor using airtight tubing.

That portion of the record of a microbarograph between any two (or a specified small number) of successive crossings of the average pressure level (in the same direction). Analogous to microseism.

A rain gauge or array of rain gauges designed to measure the inclination and direction of falling rain.

Operation mode of a communication circuit in which each end can simultaneously transmit and receive.

A unit of distance equal to 5280 feet. It is sometimes referred to as a land mile.

An instrument used to determine atmospheric pressure or elevation by observing the boiling point of water or both liquids. The sensitivity of the hypsometer increases with decreasing pressure, making it more useful for high altitude work.

Name applied to a class of instruments which measure the liquid content of the atmosphere.

A clock-driven device for recording the time of occurrence of an event or the time interval between the occurrence of events.