The Risks of Large Volcanic Eruptions

The eruption of the Hunga Tonga-Hunga Ha-apai volcano earlier this year was one of the largest in the last century. It seems to have kindled renewed interest in large volcanic eruptions. Here are links to a few articles that I've come across in the last couple of weeks about eruptions and the effects that they have had or may have in the future. 

• Hunga Tonga Volcano Update; This Eruption will Warm the Planet, Not Cool It. (YouTube link) "The destructive eruption of Hunga Tonga Hunga Ha'apai which occurred in January of 2022 was the largest explosive eruption of the 21st century. New research into the eruption has revealed something completely surprising; instead of cooling the planet slightly like other prior large explosive eruptions have, the eruption instead will warm it. So, why is this the case, and why is this eruption so unique? This video will answer these questions and discuss the highly explosive volcanic eruption." I should note that injection of water into the stratosphere would be an effect of a major ocean meteor strike.
• The volcanic eruption in Alaska that rocked ancient Egypt. "Researchers link an eruption in the Aleutian Islands to Nile flood failures during Cleopatra’s reign."
• Source of the great A.D. 1257 mystery eruption unveiled, Samalas volcano, Rinjani Volcanic Complex, Indonesia. "Based on ice core archives of sulfate and tephra deposition, one of the largest volcanic eruptions of the historic period and of the past 7,000 y occurred in A.D. 1257. However the source of this “mystery eruption” remained unknown. Drawing on a robust body of new evidence from radiocarbon dates, tephra geochemistry, stratigraphic data, a medieval chronicle, this study argues that the source of this eruption is Samalas volcano, part of the Mount Rinjani Volcanic Complex on Lombok Island, Indonesia. These results solve a conundrum that has puzzled glaciologists, volcanologists, and climatologists for more than three decades. In addition, the identification of this volcano gives rise to the existence of a forgotten Pompeii in the Far East."

Finally, here's an editorial from Nature that argues that new research is showing that large volcanic eruptions are more common than previously thought and we need to make more of an effort to prepare for them and combat their effects.

The massive eruption of the Hunga Tonga–Hunga Ha‘apai volcano this January in Tonga, in the south Pacific Ocean, was the volcanic equivalent of a ‘near miss’ asteroid whizzing by the Earth. The eruption was the largest since Mount Pinatubo in the Philippines blew in 1991, and the biggest explosion ever recorded by instruments.

Ash fell over hundreds of kilometres, affecting infrastructure, agriculture and fish stocks. The damage caused amounted to 18.5% of Tonga’s gross domestic product. Submarine cables were severed, cutting off Tonga’s communications with the outside world for several days; farther afield, the blast created a worldwide shockwave and tsunamis that reached Japanese and North and South American coastlines. Mercifully, the eruption lasted only about 11 hours. Had it gone on for longer, released more ash and gas or occurred in more densely populated areas of southeast Asia, or near a high concentration of vital shipping lanes, electricity grids or other crucial global infrastructure, it would have had repercussions for supply chains, climate and food resources worldwide1.

The world is woefully unprepared for such an event. The Tongan eruption should be a wake-up call. Recent data from ice cores suggest that the probability of an eruption with a magnitude of 7 (10 or 100 times larger than Tonga) or greater this century is 1 in 62. Eruptions of this size have, in the past, caused abrupt climate change and the collapse of civilizations, and have been associated with the rise of pandemics.

Update: Here's an interview with the authors of the Nature article.