- 行业: Weather
- Number of terms: 60695
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The American Meteorological Society promotes the development and dissemination of information and education on the atmospheric and related oceanic and hydrologic sciences and the advancement of their professional applications. Founded in 1919, AMS has a membership of more than 14,000 professionals, ...
An anemometer that utilizes the principle that the convection of heat from a body is a function of its ventilation. In its usual form it consists of a thin platinum wire heated to approximately 1000°C so that its temperature is relatively independent of ambient temperature variation. Wind speed is determined by measuring either the current required to maintain the hot wire at a constant temperature or the resistance variation of the hot wire while a constant current through the wire is maintained. Wind speeds as low as a few centimeters per second can be measured in this manner. The response time constant of the wire can be made very small. See hot-film anemometer.
Industry:Weather
An analysis showing the distribution of wind speed by means of isotachs, contours of constant wind speed.
Industry:Weather
Aggregate of rivers and other permanent or temporary watercourses, lakes, and reservoirs over any given area. See also stream network.
Industry:Weather
Adjustment of sea level to changes in barometric pressure; in the case of full adjustment, an increase in barometric pressure of 1 mb corresponds to a fall in sea level of 0. 01 m. If there is this full adjustment, the observed pressures at the sea bed are unchanged.
Industry:Weather
Accumulation of frazil under an ice cover on a river that reduces the cross section of the stream.
Industry:Weather
A zone of crowded isotherms on a synoptic upper-level chart. The temperature gradient is many times greater than normally encountered in the atmosphere.
Industry:Weather
Absorption of fluid by a solid or colloid, as in a seed swelling in the act of water absorption prior to germination.
Industry:Weather
A well drilled into the unsaturated zone for the purpose of increasing recharge by gravity.
Industry:Weather
A wide-ranging subject that consists of chemistry involving two phases, usually one or more gaseous reactants, and a condensed phase substrate where the reaction occurs, either liquid or solid. Generally the substrate facilitates the reaction and many heterogeneous reactions do not proceed in the gas phase. Reactants include free radicals as well as closed-shell molecules. Often, a reactant will hydrolyze (react with H2O) heterogeneously; in this case a major constituent of the substrate is a reactant. Common substrates are fog and rain droplets as well as aerosol in the lower atmosphere and sulfuric acid aerosol (see stratospheric sulfate layer) and water ice particles in the upper atmosphere. See polar stratospheric clouds.
Industry:Weather
