"The discovery of ancient mangrove forest remains under the Great Barrier Reef has cast doubt on some theories about how quickly the sea level rose after the last ice age.
Most scientists believe it was a gradual rise over the past 9,000 years. But the existence of relic mangroves 70cm (27in) below the floor of the Barrier Reef, some with leaves and branches still intact, suggests an abrupt rise.
Dan Alongi, a biologist at the Australian Institute of Marine Science, said it appeared that sea levels rose about 3 metres in less than 30 years, drowning forests and flooding estuaries, 20 times faster than previously thought.
"Material was very much intact, it didn't even have time to fully decompose when it was buried," he said. "So it does tell us that when climate change last happened it was comparatively quick."
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http://www.guardian.co.uk/climatechange/story/0,12374,1423983,00.html