Volcanoes pose a greater threat than a large asteroid

08/21/2022 at 22:33

EST

There is a one in six chance of a magnitude seven explosion in the next hundred years.

The probability of a volcanic catastrophe is hundreds of times greater than the combined chances of an asteroid or comet collision. There could be dozens of dangerous volcanoes scattered around the world with the potential for extreme destruction, which humanity has no idea about, experts warn.

The world is “woefully ill-prepared” for a massive volcanic eruption and the potential repercussions on global supply chains, climate and food, according to experts at the Center for the Study of Existential Risk (CSER) at the University of Cambridge.

In an article published in the journal Nature, they say there is a “widespread misconception” that the risks of major eruptions are low, and describe the current lack of government investment in monitoring this risk and responding to potential volcanic disasters as “reckless”.

The researchers argue that steps can be taken to guard against volcanic devastation, from better surveillance to more public education and magma manipulation, and the resources needed to do so are long overdue.

The volcano plays dice

“Data collected from ice cores on the frequency of eruptions in deep time suggest that there is a one in six chance of a magnitude seven explosion in the next hundred years. That’s a roll of the dice,” explains paper co-author and CSER researcher Dr. Lara Maniglobal risk expert.

“These gigantic eruptions have caused abrupt climate change and the collapse of civilizations in the distant past & rdquor ;, adds Mani.

Compare the risk of a giant eruption to that of a 1 km wide asteroid crashing into Earth. Such events would have similar climatic consequences, but the probability of a volcanic catastrophe is hundreds of times greater than the combined chances of an asteroid or comet collision, the researcher says.

An eruption in Tonga in January was the largest ever recorded instrumentally. The researchers argue that if it had lasted longer, released more ash and gas, or occurred in an area full of critical infrastructure, such as the Mediterranean, then the global shock waves could have been globally devastating.

“The Tonga eruption was the volcanic equivalent of an asteroid just hitting Earth, and should be treated as a wake-up call,” Mani says.

Lava in the volcano of La Palma. | Eph

Rash regularity

CSER experts cite recent research detecting the regularity of large eruptions by analyzing trace sulfur spikes in samples of ancient ice. An eruption ten to a hundred times larger than the Tonga explosion occurs once every 625 years, twice as many as previously thought.

“The last magnitude seven eruption was in 1815 in Indonesia,” said co-author Dr. Mike Cassidy, a volcano expert and visiting researcher at CSER.

“An estimated 100,000 people died locally and global temperatures dropped by one degree on average, leading to massive crop failures that led to famines, violent uprisings and epidemics in what is known as the year without a summer,” he said.

“We now live in a world with eight times the population and more than forty times the level of trade. Our complex global networks could make us even more vulnerable to the impacts of a major eruption & rdquor ;, concludes Cassidy.

Financial losses from a major eruption would be multimillion-dollar and on a scale comparable to the pandemic, experts say.

steps to take

Mani and Cassidy outline steps they say should be taken to help forecast and manage the possibility of a planet-altering eruption, and help mitigate the damage from smaller, more frequent eruptions.

These include a more precise identification of risks. We only know the location of a handful of the 97 eruptions classified as large in the “Volcanic Explosivity Index” during the last 60,000 years.

This means that there could be dozens of dangerous volcanoes scattered around the world with the potential for extreme destructionof which humanity has no idea.

Monitoring needs to be improved, say CSER experts. Only 27% of eruptions since 1950 have had a seismometer near them, and only a third of that data has ever again been entered into the global database for “volcanic disturbances.”

Experts also call for more research into the “geoengineering” of volcanoes. This includes the need to study ways to counteract the aerosols released by a massive eruption, which could lead to a “volcanic winter”. They also say that work should be undertaken to investigate the manipulation of magma pockets beneath active volcanoes.

Reference

Huge volcanic eruptions: time to prepare. Michael Cassidy & Lara Mani. Nature 608, 469-471 (2022). DOI:https://doi.org/10.1038/d41586-022-02177-x

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