Cryosphere glossary
the boundary layer between the troposphere and stratosphere, where an abrupt change in temperature lapse rate usually occurs; it is defined as the lowest level at which the lapse rate decreases to 2 degrees Celsius per kilometer or less, provided that the average lapse rate between this level and all higher levels within 2 kilometers does not exceed 2 degrees Celsius per kilometer; occasionally, a second tropopause may be found if the lapse rate above the first tropopause exceeds 3 degrees Celsius per kilometer.
lower part of the atmosphere, extending from the surface up to a height varying from about 7 to 9 kilometers (4.3 to 5.6 miles) at polar regions to approximately 17 kilometers (10.6 miles) in tropics; characterized by decreasing temperature with height, appreciable vertical wind motion, appreciable water vapor content, and weather.
in meteorology, an elongated area of relatively low atmospheric pressure; the opposite of a ridge.
treeless terrain, with a continuous cover of vegetation, found at both high latitudes and high altitudes.
a mineral soil showing marked evidence of cryoturbation, as indicated by broken horizons and displaced material.
a hummock consisting of vegetation and organic matter with or without a core of mineral soil or stones.
a solifluction terrace with its front covered by a vegetation mat.
ground in which two layers of permafrost are separated by a layer of unfrozen ground.
a passive heat transfer device, filled with a temperature-dependent liquid/vapour combination, installed to remove heat from the ground.
electromagnetic radiation of shorter wavelength than visible radiation but longer than x-rays; roughly, radiation in the wavelength interval from 10 to 4000 angstroms.
a hard snow surface lying upon a softer layer; may be formed by sun, rain or wind, and is described as breakable crust or unbreakable crust, depending upon wether it will break under the weight of a turning skier.
a method to determine the short-term strength of rocks; conducted by employing a constant loading rate until failure; the failure load is used to calculate the failure stress; can also be used to determine the elastic constants of rocks (i.e. Young's modulus, Poisson's ratio).
air in which static instability prevails; this condition is determined by the vertical gradients of air temperature and humidity.
the advance of a freezing front upwards from the permafrost table during annual freezing of the active layer.