A、They could be a sign of global warning. B、They are disturbing Antarctic bird habitats. C、They have destroyed research faciliti

W: Doctor White, we recently learned that a large piece of the Larsen Ice Shelf in Western Antarctica broke off in early January. Could you please tell us exactly what happened?
M: I’d be happy to. The piece that broke off was over a thousand square miles in area. More recently and quite alarming to scientists is that a forty-mile crack, some 30 feet wide in places has torn through the ice shelf.
W: I understand that the scientific community is quite concerned. What is the significance of these events?
M: Well, some scientists believe that this is a clear sign of global warming. Back in 1978, some American researchers predicted that Antarctica would show early signs of global warming due to the green house effect.
W: But couldn’t crumbling ice shelves also be a result of the unusual weather Antarctica itself has experienced lately?
M: That’s certainly possible, but you’ll have to remember that over the past thousands of years, ice shelves have been through a lot of weather changes without breaking up.
W: I think most people know that if the ice cap over Antarctica melts, the level of the oceans will rise. What sort of impact will this have?
M: Well, the ice shelves currently insulate the Antarctic continent from wind, which slows down the melting. If the winds cause even a tenth of the continent’s ice to melt, the world’s oceans could rise as much as 30 feet.
Questions 8 and 11 are based on the conversation you have just heard.
8. What has broken off in early January?
9. Why are the events important?
10. Why doesn’t the woman believe that weather is responsible for the recent events?
11. What would be the likely result of the melting of the ice cap?