Q 01/05

An iceberg is a piece of what kind of ice, over 15 metres long, broken off a glacier or ice shelf?

A) Freshwater ice

B) Frozen seawater

C) Compacted sea ice

D) Brackish ice

Answer · why

A) Freshwater ice

Frozen seawater is sea ice, a different thing; icebergs are born on land.

Q 02/05

Roughly what fraction of an iceberg's volume sits above the water?

A) About one half

B) About one third

C) About one quarter

D) About one tenth

Answer · why

D) About one tenth

Pure ice has a density of about 920 kg per cubic metre against seawater's 1,025, so Archimedes does the rest.

Q 03/05

The word 'iceberg' is a partial loan translation from which language?

A) Dutch

B) Norwegian

C) Icelandic

D) Inuit

Answer · why

A) Dutch

Ijsberg literally means 'ice mountain', with cognates in Danish, German and Swedish.

Q 04/05

Bergy bits are floating ice under 5 metres high. What are pieces under 1 metre called?

A) Ice floes

B) Growlers

C) Brash ice

D) Nilas

Answer · why

B) Growlers

Both are hard to spot on radar and dangerous to small boats.

Q 05/05

What is the technical term for a mass of ice breaking away from a glacier or ice shelf?

A) Calving

B) Shearing

C) Sloughing

D) Ablation

Answer · why

A) Calving

It is often preceded by a loud crack or boom, and blocks up to 60 metres high can crash into the water.