World coral reefs to die by 2050, scientist warns
Date: 07-Sep-01
Country: UK
Author: Ed Cropley
"It is hard to avoid the conclusion that most coral in most areas will be lost," Rupert Ormond, a marine biologist from Glasgow University, told a science conference.
"We are looking at a loss which is equivalent to the tropical rain forests."
Only the coral reefs in non-tropical regions such as Egypt stand any chance of lasting beyond 2050, Ormond said, but even the days of the stunning marine parks of the Red Sea are numbered as sea temperatures continue to creep up.
In the past, reefs have suffered from sediment build-up and the coral-eating "crown of thorns" starfish whose numbers have exploded due to the over-fishing of their predators.
Now the main threat to the delicate structures which harbour some of nature's most stunning creations comes from warmer seas, which cause coral "bleaching".
Microscopic algae which support the coral polyps cannot live in the warmer water and the polyps, the tiny creatures which actually create the reefs, die off within weeks.
Scientists agree the world's oceans are now warming at a rate of between one and two degrees Celsius every 100 years due to the increased amounts of so-called greenhouse gases in the atmosphere which trap the sun's rays.
But even if humans stopped pumping out greenhouse gases such as carbon dioxide tomorrow in a bid to halt the process, it would still be too late to save the reefs, Ormond said.
"I don't know what can be done, given that there's a 50-year time lag between trying to limit carbon dioxide levels and any effect on ocean temperature," he told the conference, held by the British Association for the Advancement of Science.
The implications stretch far beyond the death of the colourful coral structures themselves. The weird and wonderful eels and fish which inhabit the nooks and crannies will become homeless, and many species will die out.
"We are looking at a gradual running down of the whole system. Over time, the diversity of coral fish will die," Ormond said.
Mankind will also suffer directly as the dead reefs are eroded and shorelines which have been protected for the last 10,000 years face the wrath of the oceans without their natural defences.
In an age of relatively cheap SCUBA diving holidays, this also means many developing countries in the tropics, such as Kenya or the Caribbean, face losing a major source of revenue.
The only cause for optimism was that new coral reefs could start to emerge in colder waters such as the north Atlantic Ocean and Mediterranean Sea.
