The direct evaporation of snow and ice without a liquid phase.
Bergy Bit
A large piece of floating glacier ice, generally showing less than 5 meters above sea level but more than 1 metre and normally about 100-300 square meters in area.
Black Ice
Newly-formed iced over sea water. It is thin enough for the dark water to be visible through it and can be crossed only at speed by a light sledge.
Blizzard
A violent windstorm that carries dry snowflakes and is intensely cold.
Brash Ice
Accumulations of floating ice made up of fragments not more than 2m across, the wreckage of other forms of ice.
Breakout
The summer breaking up and floating away of fast ice that has built up during winter.
Calving
The breaking away of a mass of ice from an ice wall or iceberg.
CCAMLR
Convention on the Conservation of Antarctic Marine Living Resources.
Crevasse
Cracks in the ice formed when the ice moves over uneven rocks or when floating ice spreads.
CRAMRA
Convention on the Regulation of Antarctic Mineral Resources.
Diotom
Single-cell plant with siliceous shell, common in surface waters of polar regions in summer. Very important as the main photosynthesizers or "fixers" of solar energy.
Drift Snow
Loose snow that has been moved by the wind and has not yet compacted.
Fast Ice
Sea ice which forms and remains fast along the coast, where it is attached to the shore, between shoals or grounded icebergs.
Frostbite
Inflammation of the body, especially hands, face and feet, caused by exposure to extreme cold.
Glacier
A mass of slow-moving ice formed from accumulated snowfalls.
Gondwana
The early southern supercontinent composed of Africa, South America, Antarctica, Australasia and the Indian subcontinent
Grounded Ice
Any floating ice which is aground in shallow water.
Growler
A piece of sea ice smaller than a bergy bit.
Ice Edge
The demarcation at any given time between the open sea and sea ice of any kind whether fast or drifting.
Ice Floe
A large piece of floating ice.
Ice Foot
The ice that remains attached to the land after a breakout.
Ice Shelf
A floating ice sheet of considerable thickness showing 2-50 meters or more above sea level, attached to the coast.
Iceberg
A massive piece of ice greatly varying shape which has broken away from a glacier.
Katabatic
(Of wind) flowing downhill in response to gravity, e.g. masses of cold, dense air flowing down the seaward slopes of the Antarctic continent, forming strong local winds.
Krill
A tiny crustacea that feeds on plankton and forms the basis of most of the Antarctic food chain.
Lead
Any fracture or passageway through sea ice which is navigable by surface vessels.
Melt Pool
A small frozen body of fresh water in a glacier or snow surface.
Nilas
A thin elastic crust of ice, easily bending on waves and swell and under pressure. Has a matt surface and is up to 10cm in thickness.
Nunatak
The tip of a mountain that appears above the Antarctic icecap
Pack Ice
Broken pieces of floating ice which forms when storms or warmer weather melt the sea ice.
Pancake Ice
Predominantly circular pieces of ice from 30cm to 3m in diameter and up to about 10cm in thickness, with raised rims due to the pieces striking against one another.
Phytoplankton
Tiny plants that float in the ocean at the mercy of the currents.
Polynya
Any non-linear shaped opening in enclosed ice.
Pressure Ridges
Columns of ice formed by movement of ice against a shore. Usually a haphazard pile.
Rafted-up Iceberg
Large pieces of ice which have ridden up over each other.
Rafting
Pressure processes whereby one piece of ice overrides another.
Ruckle
Jumble of blocks of ice at the foot of an ice cliff.
Sastrugi
Sharp irregular ridges formed on a snow surface by wind erosion and deposition.
Sea Ice
The area of frozen sea stretching out from the land.
Seracs
Precarious large blocks of ice on an hanging glacier or large ice cliff.
Snowdrift
An accumulation of windblown snow deposited in the lee of obstructions.
Tabular Berg
A flat-topped iceberg formed by calving from an ice shelf or glacier tongue.
Tidal Hinge
The region where the sea ice joins the fast ice.
Tide Crack
The ice at the junction of the land and fast ice that is regularly broken because of tidal movements.
Wind Force
Measurements of the wind on a scale of one to twelve used by mariners.
Windscoops
Scours in a snow slope or surface caused by wind erosion.
Zooplankton
The small animals which drift in the surface waters of the ocean.
