Indonesia ? Coral that survived the 2004 tsunami is now dying at one of the fastest rates ever recorded because of a dramatic rise in water temperatures off northwestern Indonesia, conservationists said, warning Wednesday that the threat extends to other reefs across Asia.

The Wildlife Conservation Society deployed marine biologists to Aceh province, on the tip of Sumatra island, in May when surface waters in the Andaman Sea peaked at 93 degrees Fahrenheit — a 7 degree Fahrenheit rise over long-term averages.

The teams discovered massive bleaching, which occurs when algae living inside coral tissues are expelled. Subsequent surveys carried out together with Australia’s James Cook University and Indonesia’s Syiah Kuala University showed 80 percent of those corals have since died.