- 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, ...
According to the Norwegian cyclone model, the situation where a cold front catches up with a portion of a warm front above the cold frontal surface. This conceptualization of cold type occlusion development is not often observed in nature; however, it is undisputed that in strong cyclones the low center often retreats toward the cold air separating itself from the cold and warm fronts. A trough in sea level pressure is found between the cyclone center and the wave on the front, and this trough is the occluded front. Regardless of the formation processes, characteristics of a cold type occlusion are 1) a warm temperature or thickness ridge along the occluded front; 2) a trough in the sea level pressure field along the occluded front; 3) relatively colder air behind the front; and 4) an increase in lower-tropospheric static stability behind the front.
Industry:Weather
A species of cumulus characterized by small vertical development, uniform flat bases and a general similarity among clouds. Its vertical growth is usually restricted by the existence of a temperature inversion in the atmosphere; this in turn explains the unusually uniform height of the cloud tops of this cumulus species. A single cloud element that is able to penetrate the inversion may develop into cumulus congestus or even further to become cumulonimbus. As in all species of cumulus, wind shear with height may give rise to a hard appearance upshear, where cloud erosion in dry environment air is taking place, and a fuzzy appearance downshear. This species is unique to the genus cumulus.
Industry:Weather
A species of cumulus characterized by small vertical development, uniform flat bases and a general similarity among clouds. Its vertical growth is usually restricted by the existence of a temperature inversion in the atmosphere; this in turn explains the unusually uniform height of the cloud tops of this cumulus species. A single cloud element that is able to penetrate the inversion may develop into cumulus congestus or even further to become cumulonimbus. As in all species of cumulus, wind shear with height may give rise to a hard appearance upshear, where cloud erosion in dry environment air is taking place, and a fuzzy appearance downshear. This species is unique to the genus cumulus.
Industry:Weather
In coherent radar or lidar systems, the time interval over which the received signal may be regarded as approximately monochromatic. For atmospheric targets this time varies from about 1 s at a wavelength of 1 m to 1 μs at a wavelength of 1 μm.
Industry:Weather
In coherent radar or lidar systems, the time interval over which the received signal may be regarded as approximately monochromatic. For atmospheric targets this time varies from about 1 s at a wavelength of 1 m to 1 μs at a wavelength of 1 μm.
Industry:Weather
The level in the atmosphere at which a particle moving rapidly upward will have a probability of 1/e of colliding with another particle on its way out of the atmosphere. It is also the level at which the horizontal mean free path of an atmospheric particle equals the scale height of the atmosphere. The critical level of escape is the base of the exosphere. The height of the critical level, which can vary from 500 to 1000 km, is strongly dependent on the temperature of the upper thermosphere, and varies diurnally and with the level of solar activity. See cone of escape, fringe region.
Industry:Weather
The level in the atmosphere at which a particle moving rapidly upward will have a probability of 1/e of colliding with another particle on its way out of the atmosphere. It is also the level at which the horizontal mean free path of an atmospheric particle equals the scale height of the atmosphere. The critical level of escape is the base of the exosphere. The height of the critical level, which can vary from 500 to 1000 km, is strongly dependent on the temperature of the upper thermosphere, and varies diurnally and with the level of solar activity. See cone of escape, fringe region.
Industry:Weather
A system of curvilinear coordinates in which the position of a point in space is determined by 1) its perpendicular distance from a given line, 2) its distance from a selected reference plane perpendicular to this line, and 3) its angular distance from a selected reference line when projected onto this plane. The coordinates thus form the elements of a cylinder, and, in the usual notation, are written r, θ, and z, where r is the radial distance from the cylinder's z axis, and θ is the angular position from a reference line in a cylindrical cross section normal to the z axis. The relations between the cylindrical coordinates and the rectangular Cartesian coordinates (x, y, z) are x = r cos θ, y = r sin θ, z = z. See also polar coordinates.
Industry:Weather
A system of curvilinear coordinates in which the position of a point in space is determined by 1) its perpendicular distance from a given line, 2) its distance from a selected reference plane perpendicular to this line, and 3) its angular distance from a selected reference line when projected onto this plane. The coordinates thus form the elements of a cylinder, and, in the usual notation, are written r, θ, and z, where r is the radial distance from the cylinder's z axis, and θ is the angular position from a reference line in a cylindrical cross section normal to the z axis. The relations between the cylindrical coordinates and the rectangular Cartesian coordinates (x, y, z) are x = r cos θ, y = r sin θ, z = z. See also polar coordinates.
Industry:Weather
An independent variable, or predictor, in a regression equation. Also, a secondary variable that can affect the relationship between the dependent variable and independent variables of primary interest in a regression equation.
Industry:Weather
