When pieces of the ice calve off into the ocean, icebergs are formed. Icebergs occur in many shapes and sizes, and an average iceberg has a life expectancy of about 4 years until it moves into warmer water and melts. When icebergs are only a few meters across, they are called growlers. Icebergs that are tens of meters across are called bergy bits. One such iceberg broke of the Amery Ice Shelf in 1963.
Sea ice is the name given to all the ice that freezes from the sea water.
It can grow to a thickness of many feet. During the winter, the amount of ice around the continent grows substantially. Antarctic sea ice cover varies from a minimum of four million square kilometers in February to a maximum of 20 million square kilometers in September. As you can see, sea ice formation doesn't just happen all at once. As it gets colder in the Antarctic autumn, some of the open water develops needle-shaped crystals forming a slush.