Coral reefs may perish by end of century.

From Reuters: (thanks JenK)

Increasingly acidic oceans and warming water temperatures due to carbon dioxide emissions could kill off the world's ocean reefs by the end of this century, scientists warned on Monday.

The experts told a meeting in London the predicted pace of emissions means a level of 450 parts per million of carbon dioxide (CO2) in the atmosphere will be reached by 2050, putting corals on a path to extinction in the following decades.

The two dozen coral reef specialists and climate change exerts represented universities, government research offices and the Intergovernmental Panel on Climate Change.

"The kitchen is on fire and it's spreading around the house," Alex Rogers of the Zoological Society of London and the International Program on the State of the Ocean, said in a statement.

"If we act quickly and decisively we may be able to put it out before the damage becomes irreversible."

Oceans absorb large amounts of CO2 emitted by the burning of fossil fuels. But scientists say the oceans are acidifying as they absorb more carbon, disrupting the process of calcification used by sea creatures to build shells as well as coral reefs.

Researchers around the world have been urging governments to take more account of such threats to the oceans in a new U.N. treaty on fighting global warming due to be agreed in Copenhagen in December.

Coral reefs -- delicate undersea structures resembling rocky gardens made by tiny animals called coral polyps -- are important nurseries and shelters for fish and other sea life.

They also protect coastlines, provide a critical source of food for millions of people, attract tourists and are potential storehouse of medicines for cancer and other diseases.