- 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, ...
1. An atmospheric circulation in a vertical plane oriented along a meridian. It consists, therefore, of the vertical and the meridional (north or south) components of motion only. See meridional cell. 2. See meridional flow.
Industry:Weather
A very large-scale convection circulation in the atmosphere or ocean that takes place in a meridional plane, with northward and southward currents in opposite branches of the cell, and upward and downward motion in the equatorward and poleward ends of the cell. There are three annual mean meridional cells in each hemisphere, the strongest of which is the Hadley cell. A much weaker indirect cell is the Ferrel cell located between 30° and 60° latitude. There is a very weak direct cell in the polar latitudes. These are integral parts of the general circulation. Compare Hadley cell, polar cell.
Industry:Weather
In meteorology, a flow, average, or functional variation taken in a direction that is parallel to a line of longitude; along a meridian; northerly or southerly; as opposed to zonal.
Industry:Weather
The great circle on the earth that passes through the North Pole, the point in question, and the South Pole. Meridians intersect the equator at right angles.
Industry:Weather
A liquid-in-metal thermometer in which mercury is enclosed in a steel envelope. The change in internal pressure caused by the temperature variation is measured by a Bourdon tube that is connected to the mercury by a capillary tube. This instrument is very accurate and has extremely good pen control when arranged as a thermograph.
Industry:Weather
A common type of liquid-in-glass thermometer used, in meteorology, in psychrometers and as a maximum thermometer.
Industry:Weather
A liquid-in-glass thermometer or liquid-in-metal thermometer using mercury as the liquid.
Industry:Weather
The column of mercury employed in a mercury barometer, the height of which (inches of mercury) is used as a measure of atmospheric pressure.
Industry:Weather
A glass manometer, employing mercury in its vertical column, that is used to measure atmospheric pressure. The basic construction, unchanged since Torricelli's experiment in 1643, is a glass tube about three feet long, closed at one end, filled with mercury, and inverted with the open end immersed in a cistern of mercury. With the cistern surface exposed to atmospheric pressure, the height of the mercury column varies with that pressure. Mercury barometers may be classified into three groups according to their construction: cistern barometers, siphon barometers, and weight barometers. See also aneroid barometer, inch of mercury.
Industry:Weather
(Symbol Hg. ) A metallic element, atomic number 80, atomic weight 200. 61; unique (for metals) in that it remains liquid under all but very extreme temperatures. Its density of 13. 596 g cm<sup>−3</sup> and melting point of −38. 87°C (−37. 8°F) make it very useful as the medium for liquid barometers and thermometers. Mercury is very poisonous and can be absorbed through the skin. It can form organic derivatives that can enter the food chain, particularly via marine organisms. Atmospheric mercury is predominantly in the elemental form.
Industry:Weather
