- 行业: Weather
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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, ...
A satellite with its orbital plane coincident with the earth's equatorial plane. This orbit will have zero inclination angle.
Industry:Weather
The large eastward flow of electrical current in the ionosphere that occurs near noon within 5° of the magnetic equator. It causes an abnormally large maximum value of the northern component of the geomagnetic field near local noon for stations in this region.
Industry:Weather
As used by some authors, the trade winds in the summer hemisphere when they are very deep, extending to at least 8–10 km altitude, and generally not topped by upper westerlies. If upper westerlies are present, they are too weak and shallow to influence the weather. In the winter hemisphere, these easterlies are restricted to a narrow belt along the equator. Compare tropical easterlies.
Industry:Weather
An arid region existing in the equatorial trough resulting from low-level wind divergence and subsidence. The most famous dry zone is situated a little south of the equator in the central part of the equatorial Pacific.
Industry:Weather
A vertical stack of alternately eastward and westward ocean currents below the thermocline within a degree of the equator. First discovered in the Indian Ocean, equatorial deep jets have been most extensively observed and described in the Pacific. There they have a dominant vertical wavelength of 300–400 m, and are most clearly seen at depths between 500 and 2000 m. The eastward and westward relative current extreme values may be superimposed on a larger vertical scale flow that may be either eastward or westward. For example, an eastward jet may appear in a given measurement as a relative minimum in a larger-scale westward flow. On a given longitude the depths of the jets vary interannually, but there is no clear evidence for steady vertical propagation.
Industry:Weather
The system of ocean currents found in the upper Atlantic and Pacific Oceans between 20°S and 20°N. Its major components are the westward flowing North and South Equatorial Currents (NEC and SEC), which occupy most of the region. The Equatorial Intermediate Current (EIC) is a subsurface band of intensified westward movement between 2°S and 2°N at depths between 300 and 1000 m. All other components of the system are narrow (200–400 km) bands of eastward flow: the North and South Equatorial Countercurrents (NECC and SECC), found at depths between 0 and 200 m and located between 5° and 10°N and 5° and 10°S, respectively; the Equatorial Undercurrent (EUC), found on the equator at a depth of 200 m; and the North and South Subsurface Countercurrents (NSCC and SSCC), found on either side of the EIC at depths between 400 and 700 m. The major elements of the equatorial current system, particularly the NEC, SEC, NECC, and EUC, are also seen in the Indian Ocean during the northeast monsoon season (December–April) but are significantly modified during the southwest monsoon season. In addition, the Indian equatorial jet is a feature not seen in the other oceans.
Industry:Weather
The local solar time of a satellite's passage over the equator. Orbital numbers are assigned at the ascending crossing point and are advanced by one when the polar-orbiting spacecraft completes a full revolution about the poles and again reaches the equator.
Industry:Weather
A climatic zone with a climate typical of regions along the equator. See tropical climate.
Industry:Weather
The gross deviation of the earth from a spherical shape due to its rotation. The approximate shape of the earth is an ellipsoid. The equatorial radius is about 7 km greater and the polar radius about 14 km less than the corresponding radius of a sphere with the same volume as the earth.
Industry:Weather
According to some authors, the air of the doldrums or the equatorial trough, to be distinguished somewhat vaguely from the tropical air of the trade-wind zones. Tropical air “becomes” equatorial air when the former enters the equatorial zone and stagnates. There is no significant distinction between the physical properties of these two types of air in the lower troposphere.
Industry:Weather