International Association for Hydraulic Research Association
Internationale de Recherches Hydrauliques Section on Ice Problems/Seion
De Glaces
MULTILINGUAL ICE TERMINOLOGY
ADDENDUM I
Published by the Research Centre for Water Resources Budapest, 1980
BASIC ENGLISH TERMS
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Agglomerate
An ice cover of floe formed by the freezing
together of various forms of ice.
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Anchor Ice
Submerged ice attached or anchored to the bottom,
irrespective of the nature of its formation.
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Anchor Ice Dam
An accumulation of anchor ice which acts as a
dam and raises the water level.
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Beginning of the breakup (Date) Rivers
Date of definitive
breaking or movement of ice due to melting, current, or rise of water
level.
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Beginning of the breakup (Date) Lakes
Date of visual evidence
of initial deterioration along shoreline - appearance of shore leads.
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Beginning of Freeze-up (Date)
Date on which ice forming stable
winter ice cover first observed on the water surface.
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Black Ice
Transparent ice formed in rivers and lakes.
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Border Ice
An ice sheet in the form of a long border attached
to the shore.
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Brackish Ice
Ice formed from brackish water.
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Brash Ice
Accumulation of floating ice made up of fragments not
more than 2 metres across; the wreckage of other forms of ice.
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Break-up
Disintegration of ice cover.
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Break-up Date
The date on which a body of water is first
observed to be entirely clear of ice, and remains clear thereafter.
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Break-up Period
Period of disintegration of an ice cover.
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Candle Ice
Rotten columnar-grained ice.
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Channel lead
Elongated opening in the ice cover caused by a
water current.
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Columnar Ice
Ice consisting of columnar shaped grain. The
ordinary black ice is usually columnar-grained.
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Concentration
The ratio in eights or tenths of the water
surface actually covered by ice to the total area of surface, both ice
covered and ice free, at a specific location or over a defined area.
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Concentration Boundary
A line approximating the transition
between two areas of floating ice with distinctly different
concentrations.
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Consolidated Ice Cover
Ice cover formed by the packing and
freezing together of floes, brash ice and other forms of floating ice.
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Corn Snow Ice
Rotten granular ice.
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Crack
A separation formed in an ice cover of floe that does not
divide it into tow or more pieces.
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Deformed Ice
A general term for ice which has been squeezed
together and forced upwards in places /and downwards/. Subdivision are
rated ice, ridged ice, hummocked ice, and other similar deformations.
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Dendrites
Thin branch-like growth of ice on the water surface.
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Diffuse Ice
Poorly defined ice edge limiting an area of
dispersed ice; usually on the leeward side of an area of floating ice.
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Drifting Ice
Pieces of floating ice moving under the action of
wind and/or currents.
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Dry Crack
Crack visible at the surface but not going right
through the ice cover, and therefore dry.
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Duration of Ice Cover
The time from freeze-up to break-up of an
ice cover.
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Dynamic Ice
Pressure due to a moving ice cover or drifting ice.
Pressure occurring at movement of first contact termed Ice Impact
Pressure.
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Floating Ice
Any form of ice floating in water.
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Floc
A cluster of frazil particles.
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Flooded Ice
Ice which has been flooded by melt water or river
water and is heavily loaded by water and wet snow.
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Fracture
Any break or rupture formed in an ice cover or floe
due to deformation.
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Fracture Zone
An area which has a great number of fractures.
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Fracturing
Deformation process whereby ice is permanently
deformed, and fracture occurs.
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Frazil
Fine spicules, plates or discoids of ice suspended in
water. In rivers and lakes it is formed in supercooled turbulent
waters.
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Frazil Slush
An agglomerate of loosely packed frazil which
floats or accumulates under the ice cover.
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Freeze-up Date
The date on which the water body was first
observed to be completely frozen over.
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Freeze-up Period
Period of initial formation of an ice cover.
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Frost Smoke
Fog-like clouds due to contact of cold air with
relatively warm water, which can appear over openings in the ice or
leeward of the ice edge and may persist while ice is forming.
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Frozen Frazil Slush
Accumulation of slush that has completely
frozen.
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Granular Ice
Ice made of granular ice grains.
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Grounded Ice
Ice which has run aground.
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Glare Ice
Ice cover with a highly reflective surface.
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Hanging /ice/ Dam
A mass of ice composed mainly of slush or
broken ice deposited under an ice cover in a region of low flow
velocity.
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Hinge Crack
Crack caused by significant changes in water level.
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Hummocked Ice
Ice piled haphazardly one piece over another to
form an uneven surface.
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Hummock
A hillock of broken ice which has been forced upward by
pressure.
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Hummocking
The pressure process by which ice is forced into
hummocks.
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Ice Boom
Floating structure designed to retain ice.
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Ice Bridge
A continuous ice cover of limited size extending
from shore to shore like a bridge.
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Ice Clearing
Break-up prior to full melting.
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Ice Cover
A significant expanse of ice of any possible form on
the surface of a body of water.
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Ice Crossing
Man-made ice bridge.
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Ice Edge
The demarcation at any given time between the open
water and ice of any kind, whether static or dynamic. It may be termed
compacted or diffuse.
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Ice Floe
Free floating piece of ice greater than one metre in
extent.
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Ice Foot
A narrow fringe of thickened ice attached to the shore
unmoved by changes in water level.
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Ice-Free
No floating ice is present.
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Ice Gorge
The gorge or opening left in a jam after it has
broken.
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Ice Impact Pressure
/see Dynamic Ice/
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Ice Jam
An accumulation of ice at a given location which, in a
river, restricts the flow of water.
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Ice Jamming
The process of accumulation of ice to form an ice
jam.
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Ice Ledge
Narrow fringe of ice that remains along the shores of
river after break-up.
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Ice Needle
A small needle-like ice crystal formed under certain
nucleation conditions.
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Ice Pot Hole
A roundish hole formed in the ice by water motion
in a narrow crack or small hole or by the effect of radiation. It may
or may not extend through the ice cover.
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Ice Push
Compression of an ice cover particularly at the front
of a moving section of ice cover.
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Ice Rind
See ice term, similar to skim ice.
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Ice Run
Flow of ice in a river. An ice run may be light or
heavy, and may consist of frazil, anchor, slush, or sheet ice.
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Ice Sheet
A smooth continuous ice cover.
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Ice Shove
On-shore ice push caused by wind, and currents,
changes in temperature, etcetera.
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Ice Twitch
Downstream movement of a small section of an ice
cover. Ice twitches occur suddenly and often appear successively.
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Ice Wrinkle
An uneveness appearing in the surface of an ice
cover due to folding by horizontal pressure.
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Insitu Break-up
Melting in place.
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Lake Ice
Ice formed on a lake, regardless of observed location.
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Lead
Long, narrow opening in the ice.
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New Ice
A general term for recently formed ice which includes
frazil ice, slush, shugs/sludge/, and other types of ice.
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Pancake Ice
Circular flat pieces of ice with a raised rim; the
shape and rim are due to repeated collisions.
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Polynya
Any non-linear shaped opening enclosed by ice. Polynyas
may contain brash ice and/or be covered with new ice.
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Puddle
An accumulation of melt water on ice, mainly due to
melting snow but in the more advanced stages also to the melting of
ice. Initial stage consists of patches of melted snow.
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Rafted Ice
Type of deformed ice formed by one piece of ice
overriding another.
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Rafting
Pressure processes whereby one piece of ice overrides
another. Most common in new ice.
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Ridge
A line or wall of broken ice forced up by pressure. May
be fresh or weathered.
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Ridged Ice
Ice piled haphazardly one piece over another in the
form of ridges or walls.
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Ridging
The pressure process by which ice is forced into
ridges.
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River Ice
Ice formed on a river, regardless of observed
location.
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Rotten Ice
Ice in an advanced stage of disintegration.
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Rough Ice
General term for ice covers with rough surfaces.
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Sea Ice
Any form of ice originating from the freezing of sea
water.
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Shale Ice
An accumulation of thin broken plates of ice formed
when skim ice breaks up.
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Shear Crack
Crack formed by movement parallel to the surface of
the crack.
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Shearing
Motion of an ice cover due to horizontal shear
stresses.
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Shore Lead
A water opening along the shore.
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Shore Depression
Depression in the ice cover along the shore
often caused by change in water level.
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Sludge
An accumulation of spongy ice lumps formed from
compressed frazil slush, snow slush, or anchor ice.
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Skim Ice
Initial thin layer of ice on a water surface.
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Slush Ball
The result of extremely compact accretion of snow,
frazil, and ice particles. This is produced by either wind and wave
action along the shore of lakes or in long stretches of turbulent flow
in rivers.
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Slush Ice Run
Ice run composed mainly of slush ice.
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Snow Ice
Ice that forms when snow slush n an ice cover freezes.
It has a white appearance due to presence of air bubbles.
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Snow Slush
Snow which is saturated with water on ice surfaces,
or as a viscous mass floating in water after a heavy snowfall.
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Stranded Ice
Ice that has been floating and has been deposited
on the shore by a lowering of the water level.
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Static Ice Pressure
Pressure developed by a static ice cover.
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Surface Crack
Crack visible at the surface.
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Tabular Ice
A particular type of ice whose grains have large
horizontal dimensions.
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Thaw Holes
Vertical holes in ice formed when surface puddles
melt through to the underlying water.
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Thermal Crack
Crack caused by contraction of ice due to change
in temperature.
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Through Crack
Crack extending through the ice cover.
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Tide Crack
Crack caused by the rise and fall of tides.
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Unconsolidated (Ice Cover)
Loose mass of floating ice.