- Industry: 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 letter code used by aircraft in requests for information; it is also used in the supply of information to aircraft. Certain items in the code relate to meteorological information, for example, QFE refers to station pressure, QNH to altimeter setting.
Industry:Weather
A layer in the middle or upper troposphere in widespread precipitation in which ice crystals form in small convective cells and fall to lower altitudes. Such layers are thought to be characterized by convective instability. Small convective cells called generating cells that develop within the layer may produce ice crystals that then settle into lower altitudes. The base of the convectively unstable layer is called the snow-generating level. On time–height displays from vertically pointing radars, generating cells are typically observed to extend about 1–2 km above the snow-generating level. Snow trails, or streamers, are terms used to describe the trails of precipitation that subsequently emerge from the base of the generating cells.
Industry:Weather
A lead between pack ice and fast ice, or between floating ice and the shore. It may be closed by refreezing or by wind or currents so that only a tide crack remains.
Industry:Weather
A layer in the atmosphere across which there is a change of wind speed or wind direction.
Industry:Weather
A law or regulation that governs behavior, actions, or operations. In rule-based systems, only those rules with true antecedents are used. For example, a rule that begins “IF the temperature is less than 0°C. . . ” is ignored whenever the measured temperature is 0°C or higher. See IF–THEN rule, production rule, antecedent, consequent.
Industry:Weather
A laterally extensive accumulation of snow on the ground that persists through winter and melts in the spring and summer.
Industry:Weather
A large plastic constant-level balloon for duration flying at very high altitudes, used for determining wind fields and measuring upper-atmospheric parameters.
Industry:Weather
A large block of ice, generally taller than broad, formed by the fracturing of ice. Most commonly found within an icefall, at the edge of an ice cliff, or at the margins of fast- moving ice.
Industry:Weather
A large frost mound of more than one year's duration. While this Eskimo term is used in several related senses, the above meaning is becoming increasingly accepted.
Industry:Weather
A Lagrangian method for the acoustic observation of ocean currents in the interior of the ocean. The main components of a RAFOS system are a minimum of three fixed sound sources moored at intermediate depths and free-drifting floats labeling a certain water mass. The term RAFOS (SOFAR spelled backwards) was selected for this technology to indicate that the sound transmission direction is the opposite of the SOFAR technology. In both cases, the minimum in vertical profiles of sound velocity in the ocean is utilized for communication between the sources and receivers. RAFOS floats are expendable receivers that listen for coded signals from the moored RAFOS sound sources. After their underwater mission is terminated (duration up to two years), RAFOS floats drop a ballast weight, ascend to the surface, and transmit their internally stored data via satellite link to a shore-based receiving station. The RAFOS technology enables acoustic observations of ocean currents to within the millimeter per second range.
Industry:Weather
