- Industry: Weather
- Number of terms: 60695
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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, ...
The flow of electricity through a gas, resulting in the emission of radiation that is characteristic of the gas and of the intensity of the current.
Industry:Weather
A fundamental property of matter. This property exhibits two states, positive and negative, that result in the action of electric forces in the presence of an electric field. These two states were identified and named by Benjamin Franklin. The positive charge on the proton and the negative charge on the electron represent the fundamental charge, 1. 6 × 10−19 coulomb (C).
Industry:Weather
A significant increase in sea surface temperature over the eastern and central equatorial Pacific that occurs at irregular intervals, generally ranging between two and seven years. El Niño conditions, which are often characterized by “warm events,” most often develop during the early months of the year and decay during the following year. The term was originally applied by fishermen of northern Peru to a warm annual southward coastal current that develops shortly after the Christmas season; hence the Spanish name referring to “the Christ Child. ” The name subsequently became more commonly used in reference to the occasional very strong coastal warmings that are associated with torrential rains in the desert coastal regions of southern Ecuador– northern Peru. The current definition of El Niño developed following the discovery that the coastal warmings are simply part of a larger-scale phenomenon arising from coupled ocean–atmosphere interactions across a broad expanse of the equatorial Pacific. See also La Niña, Southern Oscillation, ENSO.
Industry:Weather
The mechanism by which the effects of boundary layer momentum fluxes are communicated directly to the neighboring (essentially inviscid) fluid. The mechanism involves a forced secondary circulation referred to as Ekman pumping or Ekman suction, depending on its sign. The effect is important in both the atmosphere and the ocean.
Industry:Weather
A hypothetical layer of air at the bottom of a statically neutral atmosphere surrounding a rotating planet, where surface friction and small eddies (local turbulence) cause ageostrophic, cross-isobaric winds. The spiral shape of a hodograph of this flow is called an Ekman spiral. The Ekman layer is not observed in the earth's atmosphere because of the existence of large eddies (nonlocal turbulence) creating a mixed layer, and because the earth's troposphere is statically stable on average, causing a thermodynamic cap to the boundary layer rather than a dynamic cap at a theoretical Ekman layer depth of 20 u*/f, where u* is the friction velocity and f is the Coriolis parameter. Compare atmospheric boundary layer.
Industry:Weather
The chamber that houses dropsonde equipment just prior to and during release from an aircraft. A similar piece of equipment is the dropsonde dispenser.
Industry:Weather
A special notation for writing vector equations using the scalar components of vectors rather than the vectors themselves. This notation has found widespread use in the study of atmospheric turbulence, where the many vector and tensor components of a governing equation can be concisely represented by a much smaller number of terms. The key to this notation is the use of indices (subscripts) i, j, and k, which can each take on the values of 1, 2, or 3 to represent the three Cartesian directions (x, y, z). See also alternating unit tensor.
Industry:Weather
A stream with a flow maintained by base flow during long rainless periods.
Industry:Weather
The average flow rate of material emitted into the atmosphere from a source such as a smokestack. This is the average speed of gas out of the top of a smokestack.
Industry:Weather
In Egypt and the Gulf of Suez, a westerly wind, frequent during winter and accompanied by fog and dust.
Industry:Weather
