A synoptic code approved by the World Meteorological Organization in which the observable meteorological elements are encoded and transmitted in "words" of five numerical digits length. Often abbreviated synoptic code.

Same as precipitation- effectiveness index.

A type of cistern barometer in which the level of mercury in the cistern is adjusted to the zero point of the scale before each reading.

The humidity transducinu element in a Diamond-Hinman radiosonde. Also called electrolytic strip.

A line drawn through all points on a map having the same amount of cloudiness.

In general. the severe wind of an intense tropical cyclone (hurricane or typhoon). The term has no further technical connotation, but, unfortunately, is easily conftlsed with the strictly defined hurricane-force wind,

Of equal or constant pressure, with respect to either space or time.

A mercury barometer in which the tube is U-shaped and the upper and lower mercury surfaces have the same diameter.

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 ...

The study of waters (including oceans, lakes, and rivers) embracing either: (a) their physical characteristics, from the standpoint of the oceanographer or limnologist; or (b) the elements affecting safe navigation, from the point of view of the mariner. ...

A large plastic constant-level balloon for duration flying (in excess of 24 hours) at altitudes above 40,000 feet, used for the determination of wind fields and the measurement of upper atmospheric parameters.

A seasonal wind of persistent direction, characterized by a pronounced change in direction between seasons.

See stage.

An instrument for measuring the intensity of light or the relative intensity of a pair of lights. Also called an illuminometer. If the instrument is designed to measure the intensity of light as a function of wavelength, it is called a spectrophotometer. ...

A hygrometer in which the rotation of the hygrometric element is a function of humidity.

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.

The physical exposure of an instrument. The effect of immediate environment upon the representativeness of the measurements obtained by meteorological instruments is considerable and not always correctable. The purpose of the instrument shelter is to prov ...

The point (physical and/or electrical) where two distinct data processing elements meet.

Precipitation composed of white or translucent ice crystals, chiefly in complex branched hexagonal forms.

Lowest altitude in the atmosphere over a given location at which the air temperature is 0