Sea ice in the Beaufort Sea
NASA

Related links:

Are Polar Bears on Thin Ice?

Movie showing Yearly Changes of Sea Ice Extent in the Arctic

Movie showing Yearly Changes of Sea Ice Extent in the Antarctic

Interactive: Compare Images of Arctic Sea Ice Extent Side-by-side

Interactive: Compare Images of Antarctic Sea Ice Extent Side-by-side

Activity: Graphing Sea Ice Extent in the Arctic and Antarctic

Antarctic Penguins: Bellwethers of Environmental Change

Dwindling Arctic Sea Ice

Warmer Temperatures are Changing Antarctic Phytoplankton

Sea Ice in the Arctic and Antarctic

Sea ice is frozen seawater. It floats on the oceans that are in Earth's polar regions. The salt in the seawater does not freeze. Very salty water gets trapped in the sea ice when it forms. The pockets of salty water work their way out of the sea ice over a few years. During the summer much of the sea ice melts and during the winter months it forms again. Some sea ice stays around all year long.

The Arctic Ocean has a large amount of sea ice floating at its surface, especially in winter. Sea ice is very important for the people and animals that live in the Arctic region. Animals like polar bears live on the sea ice and find their food in the ocean below it. Marine animals live under the Arctic sea ice too. In the South Polar Region, sea ice is important for penguins like the Emperor penguins in the movie "March of the Penguins".

Because of global warming, more sea ice is melting each year. Scientists are studying how animals like polar bears and penguins are affected by melting sea ice.

Last modified April 13, 2007 by Randy Russell.

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