Cryosphere glossary
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.
the minimum distance between the ground surface and frozen ground at any time during the thawing season in an area subject to seasonal freezing and thawing.
the distance from the ground surface downward to the level beneath which there is practically no annual fluctuation in ground temperature.
crack or fissure developed in fine-grained soil material as a result of shrinkage during drying.
closed, multi-sided, patterned ground feature formed by desiccation cracks in fine-grained soil material, usually less than 2 meters (6.6 feet) in diameter.
(1) (North American usage) the mean of the three largest depths of seasonal frost penetration measured during the past thirty years, or the largest depth of seasonal frost penetration beneath a snow-free soil surface measured during the past ten years (2) (Russian usage) the mean of the depths of seasonal frost penetration measured during at least the last ten years with the ground surface free of snow and the groundwater level below the depth of seasonal frost penetration.
the cumulative number of degree-days below 0 degrees Celsius, calculated by taking the average of the seasonal freezing indices for the three coldest winters in the most recent 30 years of record.