| In severe years the sea ice extends along the north coast, and in extremely severe years it reaches the south coast. |
| The melting of sea ice and glaciers on land make surface waters fresher than they are now. |
| But most arctic sea ice consists of pack ice, broken sheets moved by wind and ocean currents. |
| The bright sun shines in a cloudless sky, and a light breeze riffles the clear waters of an open pool in the sea ice of McMurdo Sound. |
| Since 1978 Arctic sea ice area has shrunk by some 9 percent per decade, and thinned as well. |
| The air above this sea ice is deprived of heat and moisture from the ocean. |
