- 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 upper portion of a two-part division of the atmosphere according to the general homogeneity of atmospheric composition; the layer above the homosphere. The heterosphere is characterized by variation in composition and mean molecular weight of constituent gases. This region starts at 80–100 km above the earth and therefore closely coincides with the ionosphere and the thermosphere. See atmospheric shell.
Industry:Weather
The top of the homosphere, or the level of transition between it and the heterosphere. It probably lies between 80 and 90 km, where molecular oxygen begins to dissociate into atomic oxygen. The homopause is somewhat lower in the daytime than at night.
Industry:Weather
The top of a haze layer that is confined by a low-level temperature inversion and has the appearance of the horizon when viewed from above against the sky. In such instances the true horizon is usually obscured by the haze layer. See also haze line, dust horizon, fog horizon, smoke horizon.
Industry:Weather
The temperature of the seawater as measured at the seawater intakes in the engine room of a vessel.
Industry:Weather
The temperature at which a mixture of air-saturated pure water and pure ice may exist in equilibrium at a pressure of one standard atmosphere. The ice point is often used as one fiducial point (0°C or 32°F) in establishing a thermometric scale because it is reproduced relatively easily under laboratory conditions. The ice point is frequently called the freezing point, but the latter term should be reserved for the much broader reference to the solidification of any kind of liquid under various conditions. See melting point; compare boiling point.
Industry:Weather
The time over which the number of radioactive nuclei of a given species decays exponentially to half its initial value. Half-lives range from small fractions of a second to billions of years. Half-life is also applied to any exponential decay. That is, if a physical quantity N at any time t is related to its initial value N0 by
the half-life for this process is τ ln 2, where τ is the mean life.
Industry:Weather
The technique of measuring radiant energy, especially radiant energy in that portion of the total electromagnetic spectrum lying within the infrared region (wavelengths between 3 and 13 μm).
Industry:Weather
The study that treats the measurement of the humidity of the atmosphere and other gases.
Industry:Weather
The sudden and usually turbulent passage of water in an open channel from low stage, below critical depth, to high stage, above critical depth. During this passage, the velocity changes from supercritical to subcritical. There is considerable loss of energy during the jump. For meteorological applications, see pressure jump. See also bore, critical velocity.
Industry:Weather
