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Cryosphere glossary

a foundation pile on which a liquid coolant refrigeration system has been installed to remove heat from the ground.
a mass of rock fragments and finer material, on a slope, that contains either an ice core or interstitial ice, and shows evidence of present movement.
the process by which characteristic landforms are currently developing as a result of thawing of ice-rich permafrost or melting of massive ice.
a general term referring to several forms of slope failures or failure mechanisms commonly occurring in the active layer overlying permafrost.
the thickness of the layer of the ground that is subject to annual thawing and freeing in areas underlain by permafrost.
the tensile or shear strength which has to be overcome to separate two objects that are bonded together by ice.
the process by which two objects are bonded together by ice formed between them.
when a mountain glacier's terminus extends farther downvalley than before; glacial advance occurs when a glacier flows downvalley faster than the rate of ablation at its terminus.
the horizontal transfer of air mass properties by the velocity field of the atmosphere.
fog which forms in the lower part of a warm moist air mass moving over a colder surface (land or water).
non-gaseous substances, divided into solid particles or liquid droplets, held in suspension in the atmosphere.
the additional ground ice formed as a direct result of permafrost aggradation.
the cumulative number of degree-days below 0° C for the air temperature during a given time period.
an extensive body of the atmosphere in which physical properties, particularly temperature and humidity, exhibit only small and continuous differences in the horizontal plane; it may extend over an area of several million square kilometers and over a height of several kilometers.
the ambient temperature indicated by a thermometer exposed to the air but sheltered from direct solar radiation, or placed in an instrument shelter 1.5 to two meters above ground; also called surface temperature.
the cumulative number of degree-days above 0°C for the air temperature during a given period.
a large depression of the ground surface produced by thawing of a large area of very thick and exceedingly ice-rich permafrost.

a non-dimensional, unitless quantity that measures how well a surface reflects solar energy; ranges from 0 - 1; a value of 0 means the surface is a perfect absorber, where all incoming energy is absorbed, a value of 1 means the surface is a perfect reflector, where all incoming energy is reflected and none is absorbed.

a low centered on the eastern slope of the Canadian Rockies in the province of Alberta, Canada.
the low pressure center located near the Aleutian Islands on mean charts of sea level pressure during the winter; it represents one of the main centers of action in the atmospheric circulation of the northern hemisphere.