SOURCE: Independent

DATE: Aug 9, 2017

SNIP: The ocean is slowly being suffocated with levels of oxygen falling at a similar rate to 94 million years ago when there was a mass extinction of marine life, scientists have warned.

While that event was caused naturally, humans are responsible for several different factors driving the increase in “dead zones” in our seas.

Writing in the journal Science Advances, the researchers said that current rates of deoxygenation were similar to those 94 million years ago during what is known as Oceanic Anoxic Event-2 (OAE-2).

OAE-2, which developed over about 50,000 years, is believed to have caused the extinction of about 27 per cent of marine invertebrates.

One of the researchers, Dr Sune Nielsen, of Woods Hole Oceanographic Institution in the US, said: “Our results show that marine deoxygenation rates prior to the ancient event were likely occurring over tens of thousands of years, and surprisingly similar to the two per cent oxygen depletion trend we’re seeing induced by anthropogenic activity over the last 50 years.

“We don’t know if the ocean is headed toward another global anoxic event, but the trend is, of course, worrying.”