Study: Oceans becoming more corrosive

HONOLULU, Feb. 20 (UPI) -- Earth's oceans may soon become more corrosive than they were when the dinosaurs died if the world's carbon dioxide emissions are not reduced.

Ken Caldeira, of the Carnegie Institution's department of global economy, said the rising levels of carbon dioxide are rapidly making the world's oceans more acidic and could cause a mass killing of marine life.

He said his computer models predict the oceans will become far more acidic within the next century. He said he compared that data with ocean chemistry evidence from the fossil record and found some startling similarities.

"The geologic record tells us the chemical effects of ocean acidification would last tens of thousands of years," Caldeira said. "But ... recovery could take millions of years. Ocean acidification has the potential to cause extinction of many marine species."

The last time oceans endured such a drastic chemical change was 65 million years ago, about the same time dinosaurs became extinct. Although researchers don't know what caused that ocean acidification, he says it was directly related to the cataclysm that wiped out dinosaurs.

Caldeira presented his findings Monday during the American Geophysical Union's annual meeting.