- 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 spectrum in which wavelengths (and wavenumbers and frequencies) are represented by the continuum of real numbers (or a portion thereof) rather than by a discrete sequence of numbers. A continuous function on an infinite interval, even though the function is nonzero over only a finite interval, must be represented by the Fourier transform rather than by Fourier series, and the resulting spectrum will be continuous. See also discrete spectrum.
Industry:Weather
A spherical particle of liquid water, from a few micrometers to a few tens of micrometers diameter, formed by condensation of water vapor on a hygroscopic aerosol particle (cloud condensation nucleus). Such drops, apparently suspended in the air with other drops, form a visible cloud. Clouds may also contain interstitial haze particles, smaller than a few micrometers (μm) in diameter. Activation distinguishes a cloud from a haze, which contains only or mainly unactivated droplets. Cloud drops differ in size from drizzle drops and raindrops. A diameter of 0. 2 mm has been suggested as an upper limit to the size of drops that shall be regarded as cloud drops; larger drops fall rapidly enough so that only very strong updrafts can sustain them. Any such division is somewhat arbitrary, and active cumulus clouds sometimes contain cloud drops much larger than this.
Industry:Weather
A species of cirrus without gray parts, the elements of which are often in the form of a comma, topped with either a hook or a tuft that is not rounded. The species uncinus is unique to the genus cirrus. The hook takes the shape of a reverse question mark under positive wind shear (wind increasing with height) conditions and the shape of a question mark under negative wind shear.
Industry:Weather
A species of cumulonimbus cloud characterized by the presence, mostly in its upper portion, of distinct cirriform parts, frequently in the form of an anvil (incus), a plume, or a vast and more or less disorderly mass of hair. This cloud is usually accompanied by a shower or thunderstorm, often by a squall, and sometimes by hail. It generally produces very apparent virga. The species capillatus is unique to the genus cumulonimbus.
Industry:Weather
A species of cumulonimbus cloud evolving from cumulus congestus. The protuberances of its upper portion have begun to lose their cumuliform outline; they loom and usually flatten, then transform into a whitish mass with more or less diffuse outlines and vertical striations. Cirriform cloud is not present, but the transformation into ice crystals often proceeds with great rapidity. Most often, this cloud is accompanied by showers. By convention, the name cumulonimbus calvus is given to any highly developed cumuliform cloud that produces lightning, thunder, or hail, although the top shows no obvious trace of transformation into ice. The species calvus is unique to the genus cumulonimbus.
Industry:Weather
A special type of chilled mirror hygrometer capable of measuring very low frost points. These low temperatures at the mirror are attained by evaporating low boiling point or cryogenic fluids. This strong cooling capability allows cryogenic hygrometers to maintain reasonable response times even at low frost points. Cryogenic hygrometers are used for airborne humidity measurements from aircraft or balloons, but also in semiconductor industries for monitoring very dry environmental conditions needed in manufacturing processes.
Industry:Weather
A small pit in an ice surface produced by the sinking of a particle of dust of cosmic origin (known as cryoconite, a fine-grained dark-colored substance).
Industry:Weather
A sky free of clouds and other obscurations as observed from the point of observation.
Industry:Weather
A small balloon used to determine the height of the cloud base. The height can be computed from the ascent velocity of the balloon and the time required for its disappearance into the cloud.
Industry:Weather
A simple wave or progressive disturbance in the one-dimensional isentropic flow of a compressible fluid, such that the pressure and density of a fluid particle increase on crossing the wave in the direction of its motion. A compression wave is illustrated, for example, by the compression of gas in a cylinder by means of a piston. When the gas is initially at rest in the cylinder, a compression wave may move into the undisturbed fluid at the speed of sound as the piston is advanced.
Industry:Weather
