Cryosphere glossary
a principal low-level cloud type (cloud genus) in the form of individual, detached elements which are generally dense and possess sharp non-fibrous outlines; these elements develop vertically, appearing as rising mounds, domes, or towers, the upper parts of which often resembles a cauliflower; the sunlit parts of these clouds are mostly brilliant white; their bases are relatively dark and nearly horizontal; near the horizon the vertical development of cumulus often causes the individual clouds to appear merged; if precipitation occurs, it is usually of a showery nature.
process of initiation or intensification of a cyclonic circulation in the atmosphere; the opposite to cyclolysis.
process of weakening or terminating of a cyclonic circulation in the atmosphere; the opposite of cyclogenesis.
area in the atmosphere in which the pressures are lower than those of the surrounding region at the same level; it is represented on a synoptic chart by a system of isobars at a specified altitude level (or a system of contours at a specified pressure level) which enclose relatively low values of pressure (or altitude); a cyclone begins when a wave (young) cyclone forms and moves along a front; a mature cyclone has well-developed warm sectors and both cold and warm fronts; an occluded cyclone is that within which there has developed an occluded front.
atmospheric circulation associated with a cyclone (depression, low pressure area); it is counterclockwise in the northern hemisphere and clockwise in the southern hemisphere.
the spatial displacement of a center of low pressure caused by the local redistribution of mass in the atmosphere; the trajectory of the center is often altered by heating or cooling on the air column, which can result from thermal fluxes at the surface or latent heat transformations associated with cloud formation and precipitation; these processes change the temperature distribution in the air column, resulting in density changes which modify the surface pressures.
the removal of ice accumulation on aircraft, ships and other objects by mechanical, thermal or chemical devices.
a sudden and destructive variety of landslide, in which loose material on a slope, with more than 50% of particles larger than sand size, is mobilized by saturation and flows down a channel or canyon.
the ability of a material to change its shape or size under the influence of an external or internal agency, such as stress, temperature, or pore pressure.
(1) the total degree of saturation of frozen soil is the ratio of the volume of ice and unfrozen water in the soil pores to the volume of the pores (2) the degree of saturation of frozen soil by ice is the ratio of the volume of ice in the soil pores to the volume of the pores.
a derived unit of measurement used to express the departure of the mean temperature for a day from a given reference (or base) temperature.
the failure strength of a material at a given strain rate or after a given period under deviatoric stress.
in meteorology, an area of low pressure (i.e. a low); usually applies to a particular stage in the development of a cyclone.
a kind of hoarfrost; ice crystals that develop by sublimation within a layer of dry snow; characterized by rapid recrystallization, usually caused by large temperature gradients; similar in physical origin to crevasse hoar; crystals are faceted, rather than rounded.
vertical interval between the top surface of a snow layer and the ground beneath; the layer is assumed to be evenly spread over the ground which it covers.