Oceans Turning Acidic Faster than Past 300 Million Years

ORIGINAL: LiveScience

Wynne Parry, LiveScience Senior Writer

02 March 2012

The single-celled organism Stensioeina beccariiformis survived the mass extinction that killed the dinosaurs but went extinct 56 million years ago, when the oceans acidified due to a massive carbon dioxide release.

CREDIT: Ellen Thomas

The oceans are becoming more acidic faster than they have in the past 300 million years, a period that includes four mass extinctions, researchers have found.

Then, as is happening now, increases in carbon dioxide in the atmosphere warmed the planet and made the oceans more acidic. These changes are associated with major shifts in climate and mass extinctions.

But while past increases in the atmosphere's carbon dioxide levels resulted from volcanoes and other natural causes, today that spike is due to human activities, the scientists note.

"What we're doing today really stands out," lead researcher Bärbel Hönisch, a paleoceanographer at Columbia University's Lamont-Doherty Earth Observatory, said in a news release. "We know that life during past ocean acidification events was not wiped out — new species evolved to replace those that died off. But if industrial carbon emissions continue at the current pace, we may lose organisms we care about — coral reefs, oysters, salmon." [Humans Causing 6th Mass Extinction]