英语听力:自然百科 澳大利亚大堡礁 Great Barrier Reef—18(在线收听

 It's an astounding mechanism, but it looks like it's being overwhelmed. Recently, the coral has been telling us that it’s had enough. Because when it overheats, it self-destructs, expelling the algae that live with them. They turn deathly pale, a process known as bleaching. It's a desperate measure will eventually kill them. So, Ove is constantly monitoring the reef to see which corals are at risk.

 
“Now there’s no point in using these instrument on these corals, because they are dead.”
 
A temperature rise of just two degrees will wipe out almost all the coral on the Great Barrier Reef--a change that could happen within the next 60 years, 
 
Ncoral, no fish, no life.
 
“We've already committed ourselves through the CO2 that we’ve put into the atmosphere to some changes on the Great Barrier Reef. Now what happens to next is really up to us.”
 
And it's not the only effect of global warming. As carbon dioxide levels rise in the atmosphere, acidity levels rise in the ocean, dissolving the living coral away from the rocks. If it continues, the Great Barrier Reef will perish. We may be the last generation to see this incredible natural wonder as it is today. But the one thing that the past has taught us is that the reef always bounces back. The question is will we be around to see it?
  原文地址:http://www.tingroom.com/lesson/zrbaike/2011/259932.html