Same as dropsonde.

An instrument used for measuring geometric angles. See radio direction-finder.

The lowest level at which the wind becomes geostrophic in the theory of the Ekman spiral. Also called gradient wind level.

The gravity flow of water within soil.

The depth of water that would result from the melting of snow or ice, assuming measurement on a horizontal surface and no infiltration or evaporation.

A contact anemometer connected to an electrical circuit which is so arranged that the average wind speed is indicated.

Solar radiation scattered by particles in the atmosphere.

The temperature at which a solid substance undergoes fusion, i.e. melts, changes from solid to liquid form. All substances have their characteristic melting points. For very pure substances the temperature range over which the process of fusion occurs is ...

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.

The transmission of data collected at a remote location over communications channels to a central station.

Same as marine rainbow.

Sir Napier Shaw's name for the approximate absolute temperature scale,

An instrument which measures the scattering function of particles suspended in a medium in order to determine the visual range through the medium. See visibility meter.

Extended Binary Coded Decimal Interchange Code. A standard code used to represent data using 8 bits per character.

A temperature-sensing element which converts thermal energy directly into electrical energy. In its basic form it consists of two dissimilar metallic conductors connected in a closed loop. Each junction forms a thermocouple. If one thermocouple is maintai ...

A flower-like diagram indicating the relative frequencies of different wind directions for a given station and period of time.

The minimum temperature shown by a minimum thermometer exposed in an open situation with its bulb at the level of the tops of the grass blades of short turf.

Occupational Safety and Health Administration. A regulatory office of the U.S. Department of Labor.

Any twelve-month period, usually selected to begin and end during a relative dry season. Used a basis for processing streamflow and other hydrologic data. The period from October 1 to September 30 is widely used in the U.S.

That part of an audio-modulated radiosonde consisting of the baroswitch, the sensing elements, the reference elements, and the relay.