Ocean life under threat

Much of the carbon碳 dioxide put into the atmosphere through fossil fuel燃料 burning is being absorbed吸收 by the seas. It's acidifying酸化 the waters, corroding腐蝕 the shells貝殼 and skeletons珊瑚 of corals骨骼, sea urchins海膽 and similar species類似的物種. Scientists want to know how conditions might deteriorate惡化 in the future and have been looking at underwater volcanoes火山, where C02 naturally bubbles through the water.

The level of acidification in these places simulates what the global oceans might look like if we keep on emitting散發 carbon dioxide二氧化碳. And the new data gathered收集 by a Plymouth University team indicates指示 the world's oceans could lose up to 30% of their biodiversity生物多樣性的 by 2100. Dr Jason-Hall Spencer led the research at volcanic火山 vents口 in Europe, the US and in Asia.

CLIP: "What we notice, unfortunately, is there're very dramatic shifts戲劇性的變化 in the ecosystem. There's a tipping point轉折點 that occurs at about the levels of ocean acidification we expect to see at the end of this century, but even before that - even within the next few years - the water becomes corrosive腐蝕性的 to the shells of organisms, and some corals can't survive."

The scientists warn that the rates of change seen in our oceans are unprecedented史無前例的, 空前的 in the recent Earth history, and the damage our seas are on course to sustain維持 could take thousands, even millions, of years to correct.

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http://www.bbc.co.uk/worldservice/learningenglish/language/wordsinthenews/2012/02/120221_witn_oceans.shtml