- 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 mathematical symbol that stands for a specific operation upon a variable or function. See linear operator, del operator, Laplacian operator.
Industry:Weather
The limiting values of ceiling, visibility and wind, or runway visual range, established as safety minimums for aircraft landings and takeoffs. Civil aircraft operate under limits stated in Civil Air Regulations and military aircraft operate under limits established by the respective military organizations. Limits for day and night operations usually differ. Also, the limits vary according to airport environment, navigational aids, and type of aircraft.
Industry:Weather
The degree to which a point on the earth's surface is in all respects subject to the influence of the sea; the opposite of continentality. Oceanicity usually refers to climate and its effects. One measure for this characteristic is the ratio of the frequencies of maritime to continental types of air mass.
Industry:Weather
A thermodynamic system so chosen that there may be transfer of mass across the boundaries; for example, an air parcel undergoing a pseudoadiabatic expansion. Compare closed system.
Industry:Weather
A numerical formulation of the governing equations of hydrodynamics applied to operational (as opposed to research) problems; typically used in reference to operational weather prediction models.
Industry:Weather
Cumulus clouds that align themselves in polygonal or elliptical shapes with clear center areas surrounded by clouds. Open-cell cumulus are found mainly over oceans in areas of strong cold-air advection.
Industry:Weather
The regular array of clear patches with a connecting lattice of cloud that comprises a layer cloud.
Industry:Weather
In U. S. Weather observing practice, the amount (in tenths) of sky cover that completely hides all that might be above it; opposed to transparent sky cover. In the case of an obscuration or partial obscuration, the total sky cover attributed thereto must be opaque.
Industry:Weather
A variety of cloud (sheet, layer, or patch), the greater part of which is sufficiently dense to obscure the sun (betweeen 10 and 20 optical depths). This variety is found in the genera altocumulus, altostratus, stratocumulus, and stratus. (Note: cumulus and cumulonimbus clouds are inherently opaque. ) In the case of altocumulus opacus or stratocumulus opacus the elements stand out in true relief at the cloud base, rather than as a consequence of varying degrees of opacity. Also, in these cases, this variety usually modifies the species stratiformis. See cloud classification.
Industry:Weather
