photo (60 ft): small floes; medium first-year (Environment Canada)
photo (5000 ft): giant floes; thick first-year (Environment Canada)
Any relatively flat piece of sea ice 20 m or more across.
Floes are subdivided to horizontal extent as follows:
GIANT: Over 10 km across.
VAST: 2 - 10 km across.
BIG: 500 - 2,000 m across.
MEDIUM: 100 - 500 m across.
SMALL: 20 - 100 m across.
