Temperature assumed by an unsaturated air parcel when brought adiabatically to a standard pressure (1,000 mb).

A scale of yellows, greens, and blues for recording the color of sea water, as seen against the white background of a Secchi disk.

Generally, the relative states of inflow, outflow, and storage of moisture over a given area of earth's surface.

Same as geostrophic wind level.

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

An instrument for determining the degree of polarization of light. See photopolarimeter.

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

Wind with a speed between 11 and 16 knots (13 and 18 mph); Beaufort scale number 4.

Diffuse solar radiation which has the same intensity in all directions.

Moisture contained in the soil above the water table, including water vapor which is present in the soil pores. In some cases this term refers strictly to the humidity contained in the root zone of plants.

An element that can control current without moving parts, heated filaments, or vacuum gaps.

Same as rain gauge.

A recording siphon barometer.

Snow shower, particularly of a very light and brief nature.

Precipitation of very small, white opaque particles of ice, fairly flat or elongated, with diameters less than 1 mm. The solid equivalent of drizzle.

A set of rules or conventions used to standardize data transfer between devices.

The processing of the form or mode of a signal so as to make it intelligible to, or compatible with, a given device.

A system of designating meteorological observing stations by number. established and administered by the World Meteorological Organization. Under this scheme, specified areas of the word are divided into "blocks" each bearing a two-number designator. Stat ...

The amount of precipitation falling in one day, or other specified period, that is likely to be equalled or exceeded in any given place only once in a century. That is, a precipitation amount that has a return period of 100 years.

Atmospheric layer throughout which there is no change of temperature with height, i.e. a zero lapse rate.