Ice Terminology

Ice shelf: a large slab of ice flowing on the sea but remaining attached to, and partly fed by, land-based ice

Glacier: a mass of ice, irrespective of size, derived from snow and continuously moving from higher to lower ground, or spreading over the sea

Icebergs: a piece of ice of the order of tens of metres or more that has been shed by a glacier into a lake or the sea

Types of Icebergs

Grounded berg: where the iceberg has run into shallow coast and is unable to move

Tabular berg: flat topped iceberg, usually derived from an ice shelf, may drift for years before melting

Rolled berg: iceberg that has literally rolled over as a result of becoming top-heavy from the lower section melting in the sea water; they tend of have a smooth, rounded shape

Calving: the process of detachment of blocks of ice from a glacier into water

Bergy bit: a piece of floating glacier ice up to several meters across, commonly derived from the disintegration of an iceberg

Growler: a piece of glacier ice almost awash, up to a few meters across, but smaller than a bergy bit

Brash ice: small fragments of glacier ice, smaller than growlers

Sea-ice: ice that forms by the freezing of the sea (**Sea water freezes at -1.8 degrees C, but it depends on the salinity of the water)

Grease ice: early ice that forms as the temperature falls and small ice crystals clump together into congealed greasy ice slicks

Pancake ice: ice spun around in waves and thickened into free floating ice disks (up to 3 meters in diameter)

Pack-ice: formed from ice floes freezing together

Polynya: area of open water within pack-ice, caused by local wind and current patterns

Fast-ice: ice attached to land

Tide crack: crack in the fast-ice caused by tidal movement of the ocean