Annual ice cycle

A crack in smooth ice with a person standing beside it holding a long, thin auger.
Expeditioner at ice fracture in the sea ice (Photo: Paul Dudley)

In winter Antarctica becomes so cold that the surrounding sea freezes for up to 300 kilometres. The ice undergoes a change in area from roughly 3 million square kilometres in the spring to 20 million square kilometres in the winter. This makes it the world's largest seasonal event!

  • Have students mark on a map of Antarctica a 300 km wide 'ice skirt' around the continent, using the maps at the bottom of the page. Ask them to think of reasons why sea ice might complicate research, and how it might help it.

Further information

The ASPECT site has information on the role of sea ice in the climate system.

For an animation of the changes in ice cover around Antarctica go to Gulf of Maine Research Institute. For satellite images showing the changes in Antarctic sea ice over the course of 12 months see fun without touching: satellite remote sensing of sea ice.

Two maps of Antarctica with variations in ice coverage shaded to show the difference between the maximum and minimum ice spread

This page was last modified on January 23, 2014.