Study: Oceans acidifying fastest in 300M years

(CBS) Because of industrial emissions, the earth's oceans are acidifying faster now than at any point in the past 300 million years, says a study by researchers at Columbia University.

According to a blog post from The Earth Institute at Columbia University Thursday, the acidity of the oceans has increased 30% in the past 100 years due to carbon emissions by human beings.

According to the post:

While the amount of carbon in the air and oceans has fluctuated naturally over time...oceans may be acidifying faster today from industrial emissions than they did during four major extinctions in the last 300 million years when carbon levels spiked naturally.

A press release put out by The Earth Institute at Columbia University describes the pH drop as possibly "unprecedented" and says the change threatens various oceanic species. Oceans soak up excess carbon dioxide from the atmosphere like a "sponge," according to the blog post, and changes in ocean acidity can affect corals, mollusks and plankton.

"(I)f industrial carbon emissions continue at the current pace," Barbel Honisch, a paleoceanographer at Columbia University's Lamont-Doherty Earth Observatory and the study's lead author, says,  "we may lose organisms we care about."

"What we're doing today," according to Honisch, "really stands out."

The international team of researchers looked at hundreds of paleoceanographic studies and determined that there was only "only one period in the last 300 million years when the oceans changed even remotely as fast as today," the release says. During that period 56 million years ago, "As many as half of all species of benthic foraminifers, a group of single-celled organisms that live at the ocean bottom, went extinct.

Researchers believe that organisms higher on the food chain may also have gone extinct in that period.

The study "raises the possibility that we are entering an unknown territory of marine ecosystem change," co-author Andy Ridgwell of Bristol University said, according to AFP.

The study appears in the journal Science.