for National Geographic News
The prehistoric bout of volcanic activity that slowly ripped Greenland from Europe triggered a deadly global warming event, a new study says (map showing Greenland and Europe today).
The event, which happened about 55 million years ago, has similarities to today's climate changes, which have been linked to human generation of greenhouse gases from fossil fuels.
(Related: Hot "Prehistoric" Conditions May Return by 2100, Study Says [September 28, 2006])
"It was a real event, and it obviously provides some interesting lessons for what's happening now," said geochronologist Michael Storey of Roskilde University in Denmark. Geochronologists date rocks, sediments, and fossils as a way of chronicling Earth's history.
The ancient climate change made the oceans much more acidic, killing many deep-sea species, the researchers report.
(Related: "Acid Oceans Threatening Marine Food Chain, Experts Warn" [April 26, 2007].)
During the event, sea-surface temperatures spiked 9 degrees Fahrenheit (5 degrees Celsius) in the tropics and more than 11 degrees Fahrenheit (6 degrees Celsius) in the Arctic.
"It seems like a cause-and-effect situation," Storey said.
He and his colleagues dated volcanic ash from the beginning of the eruptions to the start of the global warmup known as the Paleocene-Eocene Thermal Maximum (PETM). Their results will appear in tomorrow's issue of the journal Science.
James Zachos is an earth and planetary scientist at the University of California, Santa Cruz, who is an expert on the PETM.
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