That can be arranged in almost any pattern, but if it's all in one area that's a significantly large area that you could find at any time during the summer. The reason there is open water at the North Pole is because the ice cap is not, as some people might think, a stable, unchanging sheet of ice. Far from it, says Rothrock. It has floating sea ice covering it, which is typically about ten feet thick. It's not like an ice sheet or glacier on land, which is the situation at the South Pole.
Sea ice is pretty mobile stuff.
It moves around. It piles up. It's always on the go. This isn't to say that the Arctic ice cap hasn't undergone some dramatic changes. Dr. Igor Polyakov is a physical oceanographer at the International Arctic Research Center in Fairbanks.