Cryosphere glossary
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. Also known as landfast ice.
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Note: This is land fast ice.
Michael Van Woert, National Oceanic and Atmospheric Administration/Department of Commerce
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.
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Nilas showing finger rafting.
Antarctic Sea-Ice Processes and Climate (ASPeCt)
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.
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Ted Maksym, United States Naval Academy
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.
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Ted Maksym, Unites States Naval Academy
a small percolation channel that is a beginning path for surface meltwater through snow or firn.
a line following the spatial pattern of glacier movement from the top to the terminus. Englacial and supraglacial moraines make some glacier flowlines discernible from the surface.
an iceberg that is grooved into a curtain-like pattern; thought to be carved by small meltwater streams.