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soil micromorphology.

a cold wind blowing down an incline; a kind of katabatic wind.

bands of light and dark on a glacier that were formed by rock avalanching.

ice that is anchored to the shore or ocean bottom, typically over shallow ocean shelves at continental margins; fast ice is defined by the fact that it does not move with the winds or currents.

a region of space at each point of which a given physical or mathematical quantity has some definite value; for example, a gravitational field, magnetic field, or electric field; and, in meteorology, a pressure field, temperature field, etc; if the quantity specified at each point is a vector quantity, the field is said to be a vector field.

a process by which currents or winds push around thin ice so they slide over each other.

rounded, well-bonded snow that is older than one year; firn has a density greater than 550 kilograms per cubic-meter (35 pounds per cubic-foot); called névé during the first year.

the minimum elevation of firn lying on a glacier surface; each year's firn line marks a glacier's annual equilibrium line; also called firn line.

the minimum elevation of firn lying on a glacier surface; each year's firn line marks a glacier's annual equilibrium line; also called firn limit.

the height of meltwater within saturated firn that is trapped over ice in a glacier.

a thin sheet of ice formed on the glacier surface by rapid refreezing of solar-heated snow or firn, usually at high elevations during spring.

floating ice of no more than one year's growth developing from young ice; thickness from 0.3 to 2 meters (1 to 6.6 feet); characteristically level where undisturbed by pressure, but where ridges occur, they are rough and sharply angular.

glacial troughs that fill with sea water.

a navigable passage between pack ice and fast ice.

any form of ice found floating in water.

separate patch of floating ice or flat sheet of unbroken pack ice, greater than 20 meters (22 yards) across.

ice that is pushed into the underlying ocean water by the weight of thick snow cover on its surface; the salty ocean water floods the snow cover and creates a salty, slushy layer; flooded sea ice is more common in the antarctic because of more snowfall and thinner sea ice than in the arctic.

a small percolation channel that is a beginning path for surface meltwater through snow or firn.

an iceberg that is grooved into a curtain-like pattern; thought to be carved by small meltwater streams.

a warm wind blowing down an incline; a kind of katabatic wind.

a hydrometeor consisting of a visible aggregate of minute water droplets (or ice crystals), suspended in the atmosphere near the earth's surface; according to international definition, fog reduces visibility below one kilometer, fog differs from cloud only in that the base of fog is at the earth's surface while clouds are above the surface; when composed of ice crystals, it is termed ice fog.

layering in glacier ice that has distinctive crystal sizes and/or bubbles; foliation is usually caused by stress and deformation that a glacier experiences as it flows over complex terrain, but can also originate as a sedimentary feature.

alternate bands of light and dark on a glacier; usually found below steep narrow icefalls and thought to be the result of different flow and ablation rates between summer and winter.

shallow, parallel grooves on the face of a large melting ice crystal.

structure used when the soil near the ground surface is not strong and the weight of the building must be carried by deeper soil layers.

a distinct soil micromorphology, resulting from the effects of freezing and thawing processes, in which soil particles form discrete units that are densely packed.

a distinct soil micromorphology, resulting from the effects of freezing and thawing processes, in which soil particles form discrete units that are coalescing.

a sea channel connecting the Arctic Ocean and the Nordic Seas, running between Greenland and Spitsbergen. Fram Strait is the passageway where most drifting sea ice exits the Arctic.

small needle-like ice crystals, typically 3 to 4 millimeters in diameter, suspended in water, that represent the first stages of sea ice growth; they merge under calm conditions to form thin sheets of ice on the surface, frazil crystals consist of nearly pure fresh water.

fine spicules or plates of ice in suspension in water.

free water is that portion of the pore water that is free to move between interconnected pores under the influence of gravity.

freezing of a material followed by thawing.

refreezing of thawed materials.

the changing of phase from water to ice in soil or rock.

a measure of how cold it has been and how long it has been cold; the cumulative fdd is usually calculated as a sum of average daily degrees below freezing for a specified time period (10 days, month, season, etc.).

drizzle, the drops of which freeze on impact with the ground or with objects on the earth's surface or with aircraft in flight.

the advancing boundary between frozen (or partially frozen) ground and unfrozen ground.

the cumulative number of degree-days below 0 degrees Celsius for a given time period.

(1) the temperature at which a pure liquid solidifies under atmospheric pressure (2) the temperature at which a ground material starts to freeze.

the positive pressure developed at ice-water interfaces in soil as it freezes.

rain, the drops of which freeze on impact with the ground or with objects on the earth's surface or with aircraft in flight.

the number of degrees by which the freezing point of an earth material is depressed below 0 degrees Celsius.

permafrost in which the soil particles are not held together by ice.

from the point of view of the submariner, an icey canopy containing many large ice skylights or other features which permit a submarine to surface; there must be more than ten such features per 37 kilometers (30 nautical miles) along the submarine's track.

in meteorology, generally, the interface or transition zone between two air masses of different density; since the temperature distribution is the most important regulator of the atmosphere density, a front almost invariably separates air masses of different temperature; when warmer air replaces the colder, it is a warm front, and vice-versa.

the condition which exists when the temperature near the earth's surface and earth-bound objects falls below freezing (0 degrees Celsius or 32 degrees Fahrenheit).

the process of alternate freezing and thawing of moisture in soil, rock and other materials, and the resulting effects on materials and on structures placed on, or in, the ground.

a seasonal frost mound produced through doming of seasonally frozen ground by a subsurface accumulation of water under elevated hydraulic potential during progressive freezing of the active layer.

a small mound of soil material, presumed to have been formed by frost action.

a more or less symmetrical zone of frozen ground formed around a buried chilled pipeline or beneath or around a structure maintained at temperatures below 0 degrees Celsius.

the net downslope displacement that occurs when a soil, during a freeze-thaw cycle, expands normal (perpendicular) to the ground surface and settles in a nearly vertical direction.

crystals of ice that form when water vapor becomes a solid (bypassing the liquid phase) and deposits itself on the sea ice surface; frost flowers roughen the surface and dramatically affect its electromagnetic signal.

the upward or outward movement of the ground surface (or objects on, or in, the ground) caused by the formation of ice in the soil.

the difference between the elevations of the ground surface before and after the occurrence of frost heave.

cumulative upward displacement of objects embedded in the ground, caused by frost action.

any mound-shaped landform produced by ground freezing combined with accumulation of ground ice due to groundwater movement or the migration of soil moisture.

the movement of the freezing front into the ground during freezing.

effects of frost action on earth materials and on structures placed in or on the ground.

the highest temperature at which atmospheric moisture will sublimate in the form of hoarfrost on a cooled surface; it is analogous to the dew point.

the mechanical disintegration of rock by the pressure of water freezing in pores and along grain boundaries.

fog-like clouds, due to the contact of cold air with relatively warm water, which appear over newly-formed leads, or leeward of the ice edge, and which may persist while new ice is forming.

the differential movement of soil particles of different sizes as a result of frost action.

the disintegration and break-up of soil or rock by the combined action of frost shattering, frost wedging and hydration shattering.

the mechanical disintegration, splitting or break-up of rock by the pressure of water freezing in cracks, crevices, pores, joints or bedding planes.

ground (soil or rock) in which little or no segregated ice forms during seasonal freezing.

soil in which little or no segregated ice forms during seasonal freezing.

ground (soil or rock) in which segregated ice will form (causing frost heave) under the required conditions of moisture supply and temperature.

soil in which segregated ice will form (causing frost heave) under the required conditions of moisture supply and temperature.

the zone in a freezing, frost-susceptible soil between the warmest isotherm at which ice exists in pores and the isotherm at which the warmest ice lens is growing.

soil or rock in which part or all of the pore water has turned into ice.

the phase transition of a substance passing from the solid to the liquid state, melting; in meteorology, fusion is understood to refer to the melting of ice, which, if the ice is pure and subjected to one standard atmosphere of pressure, takes place at the ice point of 0 degrees Celsius (32 degrees Fahrenheit).

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