Sixth mass extinction of Earth by 2100

Pablo Tucker
September 22, 2017

Geologists have always been fascinated with past extinction events and now it appears we're may be headed for another one by the end of the century.

The Independent UK further quoted him saying, "By analyzing 31 carbon isotopic events during the past 542 million years, I identify the critical rate with a limit imposed by mass conservation".

In the history of life on Earth, there have been five mass extinction events, with the most extreme example, the Permian extinction, wiping out some 95 percent of all marine life. Unusually high increases in global carbon, leading to a destabilization of practically every ecosystem, with a punctuated impact on oceans.

Increasing carbon levels in the oceans may lead to the sixth mass extinction in Earth's history by about 2100, MIT scientists have predicted after analysing data from the last 540 million years.

Does this mean that mass extinction will soon follow at the turn of the century? "But how that process plays out remains unknown", the paper said.

The data suggests that the carbon cycle in the nature will be unstable in the near future, and its behavior can not be predicted. Finally, he plotted both the mass and timescale of each event.

He then compared his prediction to the total amount of carbon added to the Earth's oceans by the year 2100, as projected in the most recent report of the Intergovernmental Panel on Climate Change.

From this, he constructed a database to assess how much carbon mass was pumped into the world's oceans in each historical event.

By looking at that critical rate, as well as the 10,000-year timescale it takes for the marine carbon cycle to correct itself after a major disruption, Rothman calculated how much carbon it would take today to tip us over the threshold.

Professor Rothman's analysis identified "thresholds of catastrophe" in the carbon cycle that, if exceeded, would lead to an unstable environment, and ultimately, mass extinction. He also analysed that 310 gigatonnes carbon is required to lead Earth to its 6th mass extinction, which is likely to happen by the year 2100. "It became evident that there was a characteristic rate of change that the system basically didn't like to go past". They were relatively benign - not enough to destabilise the system toward catastrophe. But that threshold was crossed four times, corresponding to four of the five worst mass extinctions.

Rothman said there were similarities now because of man-made global warming.

"There should be ways of pulling back [emissions of carbon dioxide]", he says.

Most of the other half has dissolved into the ocean, causing acidification. In most of these episodes, the carbon volume stayed under a certain threshold.

'But this work points out reasons why we need to be careful, and it gives more reasons for studying the past to inform the present'.

Up to now, there's been strong evidence that, because of human activity, we are sprinting towards the sixth great mass extinction. The research is published in Science Advances. American scientist predicts that it will take about 310 additional gigatons of carbon in the world ocean waters to cross the threshold and enter the "area of instability".

Other reports by iNewsToday