Maxed out on disaster yet? Group warns of volcanic risk

The world is “woefully unprepared” for a massive volcanic eruption and the likely repercussions for global supply chains, climate and food. That’s according to experts from the University of Cambridge’s Centre for the Study of Existential Risk (CSER).

Mount Rinjani in Indonesia, site of an eruption in 1257, the biggest in the last millenium (magnitude 7).

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

However, they argue that steps can be taken to protect against volcanic devastation – from improved surveillance to increased public education and magma manipulation.

“Data gathered from ice cores on the frequency of eruptions over deep time suggests there is a one-in-six chance of a magnitude seven explosion in the next one hundred years. That’s a roll of the dice,” said CSER researcher Dr Lara Mani, who co-authored the article with researchers from the University of Birmingham.

“Such gigantic eruptions have caused abrupt climate change and collapse of civilisations in the distant past.”

Mani compares the risk of a giant eruption to that of a 1km-wide asteroid crashing into Earth. Such events would have similar climatic consequences, but the likelihood of a volcanic catastrophe is hundreds of times higher than the combined chances of an asteroid or comet collision.

“Hundreds of millions of dollars are pumped into asteroid threats every year, yet there is a severe lack of global financing and coordination for volcano preparedness,” she said, adding that this urgently needs to change.

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

“The Tonga eruption was the volcanic equivalent of an asteroid just missing the Earth, and needs to be treated as a wake-up call,” said Mani.

The CSER experts cite recent research detecting the regularity of major eruptions by analysing traces of sulphur spikes in ancient ice samples. An eruption ten to a hundred times larger than the Tonga blast occurs once every 625 years – twice as often as had been previously thought.

“The last magnitude seven eruption was in 1815 in Indonesia,” said co-author Dr Mike Cassidy. “An estimated 100,000 people died locally, and global temperatures dropped by a degree on average, causing mass crop failures that led to famine, violent uprisings and epidemics in what was known as the year without summer,” he said.

Financial losses from a large magnitude eruption would be in the multi-trillions, and on a comparable scale to the events of 2020, say the experts.

Steps they say need to be taken to help forecast and manage the possibility of a planet-altering eruption include a more accurate pinpointing of risks. We only know locations of a handful of the 97 eruptions classed as large magnitude on the “Volcano Explosivity Index” over the last 60,000 years. So there could be dozens of dangerous volcanoes out there, about which humanity has no clue.

Monitoring must be improved. Only 27% of eruptions since 1950 have had a seismometer anywhere near them, and only a third of that data again has been fed into the global database for “volcanic unrest”.

Another worthwhile point o attack is research into volcano “geoengineering”. This includes the need to study means of countering aerosols released by a massive eruption, which could lead to a “volcanic winter”. They also say that work to investigate manipulating pockets of magma beneath active volcanoes should be undertaken.