21.   Scientists have worried for decades that the Antarctic ice sheet was shrinking, threatening a global rise in sea level.

22.   Two polar explorers who were stranded on an Antarctic ice shelf for two days have been airlifted to McMurdo Station where they were quickly snowed in again.

23.   Already glaciers are in retreat, a large part of the Antarctic ice shelf has broken away and tropical coral reefs appear to be dying because of global warming.

24.   Cracks have appeared in another section of a vast Antarctic ice shelf, the northern section of which collapsed two years ago, a leading geologist says.