- 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 state in which the equatorial atmosphere of a celestial body has a larger absolute angular velocity than the more poleward portions of the atmosphere. An equatorial acceleration is exhibited by the Sun, Jupiter, and Saturn. The term is a misnomer since it involves a lateral angular shear, not an acceleration.
Industry:Weather
Geographically, on the earth's surface, the imaginary great circle of latitude 0°, which is equidistant from the poles, and which separates the Northern Hemisphere from the Southern Hemisphere. See meteorological equator, heat equator, thermal equator, celestial equator, aclinic line, geomagnetic equator.
Industry:Weather
The difference at any instant between the apparent solar time and the mean solar time as measured at a specified place; it is the difference between the hour angles of the apparent sun and the mean sun. Tables of the equation of time are available in astronomical almanacs. The equation of time is zero at four times during a year, on about 15 April, 15 June, 31 August, and 24 December, at present. The algebraic sign associated with the equation of time varies from one source to another, a fact that must be kept in mind in abstracting values from almanacs. See apparent solar day, mean solar day.
Industry:Weather
A flat map so drawn that equal units of actual (or represented) area in any two portions of the map have identical map areas. For maps representing portions of the earth's surface this is obtained by continuously changing the scales of the meridians and parallels. Equal-area maps covering the whole globe, such as the Sanson–Flamsteed sinusoidal projection, are approximately elliptical. In Lambert's azimuthal equal- area projection, the parallels of latitude come closer together as the equator is approached. Any map of the whole world or of a hemisphere necessarily distorts the shape of a region far from the center of the map, but such maps are useful for some climatological studies in which the correct representation of area is important. For limited parts of the globe equal-area projections are quite practical. Compare conformal map.
Industry:Weather
Cyclic compound formed by adding a single oxygen atom across the double bond of an alkene. These reactive compounds are used in industrial-scale organic synthesis.
Industry:Weather
1. The formal geochronologic unit, longer than a geologic age and shorter than a geologic period, during which the rocks of the corresponding series were formed (from Glossary of Geology 1997). 2. A term used informally to designate a length (usually short) of geological time, for example, glacial epoch. 3. In paleomagnetism, a date to which measurements of a time-varying quantity are referred, for example, “a chart of magnetic declination for epoch 1965. 0,” or informally as a magnetic polarity epoch. Magnetic polarity refers to whether the geomagnetic field was like it is today (normal polarity) or whether the north and south poles are reversed from their present configuration (reversed polarity).
Industry:Weather
Large reactors, usually made of glass or polytetrafluoroethylene (PTFE) film, in which gas-phase chemical reactions are carried out to simulate changes occurring in the atmosphere. Either natural sunlight or artificial ultraviolet lighting can be used to initiate the chemistry. The buildup of products such as nitrogen dioxide and ozone is monitored using techniques such as gas chromatography or infrared spectroscopy.
Industry:Weather
The general term applied to the study of a variety of atmospheric sound propagation phenomena, including frequency-dependent molecular absorption, refraction by wind and temperature gradients, diffraction by topography, buildings, trees, etc. , and scattering by turbulence. Also of interest are sounds, some of atmospheric origin, ranging from infrasonic emissions by thunderstorms and large explosions to ultrasonic emissions by high-power turbines and transducers used for materials testing.
Industry:Weather
A group of waves with an envelope (the curve touching the surface near the wave crests) that propagates without change of form, as a solitary wave. Under certain circumstances, ocean wave groups have approximately this behavior.
Industry:Weather
External conditions and surroundings, especially those that affect the quality of life of plants, animals, and human beings. In agriculture the environment includes the air, soil, and water conditions.
Industry:Weather
