- 行业: Weather
- Number of terms: 60695
- Number of blossaries: 0
- Company Profile:
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, ...
A current-measuring instrument employing the transmission of high-frequency acoustic signals in water. The current is determined by a Doppler shift in the backscatter echo from plankton, suspended sediment, and bubbles, all assumed to be moving with the mean speed of the water. Time gating circuitry is employed, which uses differences in travel time to divide the water column into range intervals called bins. The bin determinations allow development of a profile of current speed and direction over the entire water column. The ADCP can be deployed from a moving vessel, towing platform, buoy, or bottom-mounted platform. In the latter configuration, it is nonobtrusive in the water column and thus can be deployed in shipping channels.
Industry:Weather
The separation of a sound wave into its frequency components as it passes through a given medium. The velocities of the wave components change as they pass through the medium.
Industry:Weather
Scattering of sound or ultrasound in the direction of the source.
Industry:Weather
A sound-transmitting or receiving system with elements arranged to give desired directional characteristics.
Industry:Weather
The line through those points on the earth's surface at which the magnetic inclination is zero. The aclinic line is a particular case of an isoclinic line. In South America the aclinic line lies at about 15°S latitude, while from central Africa to about Indochina it coincides approximately with the parallel of 10°N latitude. Compare agonic line, geomagnetic equator.
Industry:Weather
A record of the H+ concentration in an ice core. Unless otherwise stated, the H+ concentration is indirectly determined by the measuring the electrical conductivity. Annual layering, volcanic activity, periods with abundant alkaline dust, and biomass burning can sometimes be detected.
Industry:Weather
The quantitative capacity of aqueous media to neutralize strong bases. The acidity of a water sample is determined by titrating it with a strong base (e.g., NaOH) to a defined pH.
Industry:Weather
A popular expression for the deposition by rainfall of various airborne pollutants (especially SO2 and NO2) that have harmful effects on vegetation, soils, buildings and other external structures.
Industry:Weather
Chemicals not occurring naturally in the atmosphere that either are acidic, or that easily react or dissolve in water to become acidic.
Industry:Weather
