Ice, Bergs, Etc.

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Ice comes in many shapes and sizes. As it forms, a thin sheet of ice called grease ice appears on the surface. It looks a bit like a grease slick. The ice thickens in areas to form small pancake shapes. As the small pancakes come together they form larger pancakes, and so on. Ultimately what forms is a network of large pancakes making up the pack ice. As the pack ice moves with the water pieces often hit each other creating small mountains of ice from the impact, a buckling effect. Often you will see in these buckled areas what is called blue ice. When ice forms from saltwater the salt seeps out into the water below so that what is left is freshwater-ice. When the light filters through the buckled areas the ice appears blue. Below are examples of the different types of ice you would see at sea in the Antarctic.

When large pieces of an ice shelf or a glacier break off into the sea icebergs are formed.

What you see above water is only a small part of the whole berg. Two-thirds of the berg remain underwater. The biggest iceberg on record was 208 miles by 60 miles, bigger than some small countries. Icebergs usually last several years before melting as they drift northward.

Go To Photos of the Ross Ice Shelf

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