- 行业: Weather
- Number of terms: 60695
- Number of blossaries: 0
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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, ...
Branch of hydrology of the land surface dealing with rainfall–runoff relationships and the general water budget on the surface of the earth.
Industry:Weather
Body of water moving under the influence of gravity, to lower levels, in a well-defined natural channel.
Industry:Weather
Aviation forecast for a specific air route or for a specific portion of an air route. See'' also'' ROFOR, ROFOT, ROMET, flight cross section, route cross section.
Industry:Weather
Averaging out the effects of waves to determine sea level. The measurements can be made in several ways, for example, for the reading of tide poles, the averaging is by eye, in stilling wells the waves are damped out by a narrow constriction, acoustic and pressure gauges may apply electronic averaging to rapid samples, and satellite altimetry is corrected for general wave conditions within the footprint of the transmission.
Industry:Weather
Audio frequency signals, usually regarded as noise, that are detected by radio receivers. Radio noise emitted by lightning is the most common natural source of static. There are also many common man-made sources, such as corona discharges from high-voltage transmission lines, defective vehicular ignition systems, and high-power switching relays for large motors.
Industry:Weather
Averaging a wave characteristic over one full cycle. Buoyant oscillations in the form of gravity waves can exist in the atmosphere and ocean, and these oscillations can transport momentum and energy. However, the amount of transport often oscillates too, so an instantaneous measure of these momentum or energy fluxes would not be representative. A better value is obtained by measuring the transport at many closely spaced intervals during the passage of any one wave, and then finding the mean value of the measurements.
Industry:Weather
Attenuation of electromagnetic waves propagating through precipitation. Depending on the wavelength of the radiation, the attenuation is accounted for by some combination of absorption and scattering by the precipitation particles. The relative importance of scattering tends to increase as the wavelength becomes shorter. For radar, the specific attenuation ''Y'' (dB km<sup>−1</sup>) due to rain is described by empirical power relations of the form ''Y'' = ''aR<sup>b</sup>'', where ''R'' (mm h<sup>−1</sup>) is the rainfall rate, and ''a'' and ''b'' are empirical constants that depend on wavelength and temperature. The specific attenuation of snow is less than that of rain, and for wavelengths of 10 cm and longer is usually negligible. For lidar, the precipitation attenuation is approximately proportional to the cross-sectional area of the precipitation particles per unit volume. See rain attenuation; Compare cloud attenuation.
Industry:Weather
Atmospheric processes that cannot be adequately resolved within a numerical simulation. Examples can include turbulent fluxes, phase changes of water, chemical reactions, and radiative flux divergence. Such processes are often parameterized in numerical integrations and even neglected in some applications. See parameterization, convective adjustment, Mellor–Yamada parameterization, shallow convection parameterization.
Industry:Weather
Atmospheric motions that fulfill the principles and requirements of quasigeostrophic theory.
Industry:Weather
Atmospheric motion that fulfills the principles and requirements of semigeostrophic theory.
Industry:Weather
