CORAL GRIEF; Global warming will kill reefs 'in 20yrs'.

CATASTROPHE threatens the world's coral reefs, leading scientists warned yesterday.

Global warming and pollution have already destroyed more than a quarter of them and without drastic action the rest may be dead in 20 years.

That will mean starvation for millions of fishermen and their families. Thousands of fish species also risk becoming extinct.

The threat was revealed at an international conference attended by 1,500 environmentalists in Bali, Indonesia.

They disclosed that in some worst-hit areas, like the Maldives and Seychelle Islands, up to 90per cent of corals have been killed in the past two years by an increase in water temperature.

Australian scientist Clive Wilkinson said: ''You have to go and look at coral reefs now... we are losing them fast ."

Governments must wake up and reverse global warming trends," he added.

Colleague Ove Hoegh-Guldberg said coral reefs generated an estimated pounds 25bn a year in fishing and tourism. A total of 26 per cent had already been destroyed. He added: "The world's attitude to global warming must change."

Raw sewage and over-fishing are major problems but the most serious and immediate threat is warming. A rise in water temperatures of just a few degrees did massive damage. The heat stresses the coral, forcing it to expel the microscopic plants which give its vibrant colour. If the coral is not cooled, it dies.

TONY Blair will today announce a pounds 100m drive to cut pollution. In a major speech in London he is expected to unveil plans for a pounds 50m trust" aimed at cutting emissions from cars and factories. A further pounds 50m will be channelled into developing new energy sources from the wind, waves and the power of the sun.