Sea Ice in the Arctic and Antarctic Sea ice is frozen seawater.
It can be several meters thick and it moves over time. Although
the salts in the seawater do not freeze, pockets of concentrated
salty water become trapped in the sea ice when it first forms.
The pockets of salty water can work their way out of the sea ice
over a few years. During the summer months 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 surrounding and underlying ocean.
Marine life exists under the Arctic sea ice too. Over the past
few decades, more and more of the sea ice has been melting in
the summer as Earth’s climate warms. Scientists predict that
within the next 40 years with continued global warming, there
will be no sea