Strong winds concentrated within a narrow band in the atmosphere. The jet stream often "steers" surface features such as front and low pressure systems.

Radiation with wavelengths greater than 4 microns. (In meteorology, same as infrared radiation.)

Wind with a speed below 1 knot (1 mph); Beaufort scale number 0.

The degree of conformity of an indicated value to an accepted standard value, or ideal value. See accuracy rating, measured accuracy.

See bimetallic thermometer.

Any one of a family of circular arcs consisting of concentric colored bands, arranged from red on the inside to blue on the outside, which may be seen on a "sheet" of water drops (rain, fog, spray). The most common of the many possible is the primary rain ...

Same as water year.

A graphical representation of stage or discharge at a point on a stream as a function of time.

A hygrometer using goldbeater's skin as the sensitive element. Variations of the physical dimensions of the skin caused by its hygroscopic character indicate relative humidity. (Note: Goldbeater's skin is the prepared outside membrane of the large intesti ...

An instrument for measuring the extinction coefficient in water.

Apparatus from which the nature and time of precipitation may be determined.

The process of modifying some characteristic of a wave (the carrier) so that it varies in step with the instantaneous value of another wave (the modulating wave) in order to transmit a message. The modified characteristic may be frequency, phase, and/or a ...

Solar and terrestrial radiation directed upward (away From the earth's surface); outgoing radiation.

An instrument for measuring the ultraviolet in solar and sky radiation.

Line drawn through geographical points recording equal amounts of precipitation during a given time period or for a particular storm.

Same as luminous intensity.

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.

An elongated area of relatively low atmospheric pressure. Usually associated with and most clearly identified as an area of maximum cyclonic curvature of the wind flow. The opposite of a ridge.

A thermometer which uses a transducing element whose element proper-ties are a function of its thermal state. Common meteorological examples of such thermometers are the resistance thermometer and the thermoelectric thermometer.

An instrument for collecting liquid water from the atmosphere.