Cryosphere glossary
fabric
soil micromorphology.
fall wind
a cold wind blowing down an incline; a kind of katabatic wind.
false ogives
bands of light and dark on a glacier that were formed by rock avalanching.
fast ice
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.
Image
Michael Van Woert, National Oceanic and Atmospheric Administration/Department of Commerce
field
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.
finger rafting
a process by which currents or winds push around thin ice so they slide over each other.
Image
Antarctic Sea-Ice Processes and Climate (ASPeCt)
firn
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.
firn limit
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.
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.
firn water table
the height of meltwater within saturated firn that is trapped over ice in a glacier.
firnspiegel
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.
first-year ice
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.
Image
Ted Maksym, United States Naval Academy
fjord
glacial troughs that fill with sea water.
flaw lead
a navigable passage between pack ice and fast ice.
floating ice
any form of ice found floating in water.
floe
separate patch of floating ice or flat sheet of unbroken pack ice, greater than 20 meters (22 yards) across.
flooded sea ice
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.
Image
Ted Maksym, Unites States Naval Academy
flow finger
a small percolation channel that is a beginning path for surface meltwater through snow or firn.
flowline
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.
fluted berg
an iceberg that is grooved into a curtain-like pattern; thought to be carved by small meltwater streams.