Super eruptions in Australian volcanos around 252-56 million years ago led to catastrophe that killed 85% of all species at the time.
A volcano in present-day Russian Siberia erupted around 252 million years ago, spewing large amounts of carbon dioxide and methane into Earth’s atmosphere, depriving oceans of oxygen, and killing around 85 per cent of all species on the planet at the time.
This is what existing research suggests. Recently, however, researchers have found that it was not a singular event. They suggested that there were also volcanic explosions in China that were part of a “two-punch” geological activity – the other being the Siberian eruption.
The latest research – published this week – suggests that the Siberian and Chinese volcanic activity only added to the extreme climatic activities that were already happening. The research found that massive volcanic “super eruptions” in Australia – besides those in China and Siberia – also added to that climate catastrophe at the time that wiped 85 per cent of all life at the time.
The research, published in Nature journal by a group of American and Australian researchers, discovered ancient volcanic activity in Australia that not only shaped Australian climate but also added to the contemporary extreme climatic events.
They noted in their study that sea temperatures had risen by 6-8*C over thousands of years by the time of these “super eruptions”, so they did not cause the catastrophe in itself but were part of a number of causative factors.
Volcanoes in Australia’s New South Wales spewed at least 1,50,000 cubic kilometres of ash and gases during 252-256 million years ago.
Three authors of the study provided a perspective of the scale of eruption in an article in The Conversation. They wrote, “The 79 AD eruption of Mt Vesuvius, which obliterated the Italian city of Pompeii, produced just 3–4 cubic kilometres of rock and ash. And the deadly Mt St Helens eruption in 1980 was about 1 cubic kilometres.”
It shaped the Australian landscape forever. The authors noted, “Today’s coal deposits in eastern Australia show ancient forests used to cover much of this land. After the super eruptions, however, these forests were abruptly terminated in a series of bushfires over some 500,000 years.”
Timothy Chapman, Ian Metcalfe, and Luke Milan noted that the Australian super explosions affected all the ancient continents and led to the rise of dinosaurs.
They wrote, “Australia’s super eruptions were a key marker of change in the ancient world. And this collapse of ecosystems was not limited to Australia, either. The catastrophic event affected all of the ancient continents. It had a substantial influence on the evolution of life — which eventually led to the rise of the dinosaurs.”
The study highlights that while one cause might appear for a significant event – such as a natural disaster, there are likely many causes.
Initially, it was believed that the Siberian explosions killed 85 per cent of all life on Earth at the time. Later discoveries from China and Australia suggested that all of these activities over a long period of time caused this climate catastrophe.
The study also highlights that what happens in one country does not have consequences for that country alone. The research on ancient Chinese eruptions had worldwide consequences just like the ancient Australian eruptions.
“There would have been global effects on climate as material from the eruptions would have been carried around the globe by stratospheric winds,” New Scientist quoted Michael Rampino of New York University as saying.
In the present-day context, experts have highlighted that a global effort is needed to deal with climate change. Ancient catastrophes reinforce the requirement as they show that a disaster in one country can affect all continents.