Hunga Tonga, a harbinger of things to come?/Wikimedia Commons

While you worry about global warming from the carbon dioxide build-up in the atmosphere above, vulcanologists are now warning that you should also be worrying about the heat that lurks below.

They’ve handicapped the odds of a massive volcanic explosion disrupting life on the planet at one in six this century and, in a paper published in Nature this week, questioned whether humanity recognized the be-prepared warning from a recent eruption in Tonga “or will a large-magnitude eruption be the next planet-disrupting event to catch the world unawares after the pandemic?”

The Hunga Tonga–Hunga Ha‘apai volcano eruption (click here to see the video captured by a Tonga Geological Survey Team) that devastated the island in January and sent vibrations rippling around the globe was small when compared to the explosions the geologic record predicts, they warned.

“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 6,” they wrote. “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.

“The world is woefully unprepared for such an event. The Tongan eruption should be a wake-up call.”

Better volcano monitoring is needed, they said, and some research effort should be directed toward how to “curtail a volcanic winter.

“…It is theoretically possible to release a short-lived warming agent, such as a hydrofluorocarbon, to counteract the cooling of sulfates, or to use a high-altitude aircraft to release non-toxic substances that bind to sulfate aerosols to enhance their removal from the atmosphere, in a manner similar to cirrus-cloud thinning. Such efforts might have significant costs and side effects, such as acid rain, as well as large potential benefits.”

More than a century has passed since the last magnitude-7 eruption in Tambora, Indonesia, in 1815.

“In the archipelago, an estimated 100,000 people died as a result of volcanic flows, tsunamis, the deposition of heavy rocks and ash on crops and houses, and subsequent effects,” wrote authors Michael Cassidy from the University of Birmingham and Lara Mani from the University of Cambridge. “Globally, temperatures dropped about 1 °C (1.8 degrees Fahrenheit) on average, causing the ‘year without a summer’. The eastern United States and much of Europe endured mass crop failures, and the resulting famines led to violent uprisings and disease epidemics.”

And now?

The more technologically sophisticated world of today is in some ways better prepared to deal with the consequences of a year without a summer, but it is also facing climate-change-driven shifts in ocean and atmospheric circulation that could compound the danger of a large-magnitude eruption in the tropics and in the process cause “60 percent more cooling in the next century compared with today. The frequency of eruptions could also increase as geophysical forces on the planet’s surface shift because of ice melt, changes in precipitation and sea-level rise.

“The global population is eight times larger now than in 1800, and the trade it relies on has grown more than 1,000-fold since then. As the COVID-19 pandemic and the war in Ukraine have shown, the modern world is highly dependent on global trade for food, fuel and resources; a disaster in one spot can cause price spikes and shortages far away.

“The financial losses resulting from a large-magnitude eruption are estimated to be in the multi-trillions, roughly comparable to those of the pandemic. Given the estimated recurrence rate for a magnitude-7 event, this equates to more than $1 billion per year. Investing in crisis preparedness and mitigation would be far cheaper than reacting to a disaster.”

Pandemic losses were inflated by global lockdowns that were part of an effort to wipe out the SARS-CoV-2 virus before it became endemic. Just about every government save that of China has now accepted that battle was lost long ago and that the human population from here on is going to be dealing with SARS-Co-2 in the way it has dealt with influenza, the common cold and other contagious diseases.

Humankind might be able to inflate the consequences of a massive volcanic eruption, too, but the projections of Cassidy and Mani are based on an analysis by the Cambridge Centre for Risks Studies that ignored the compounding of economic costs due to political blundering.

Researchers there in 2018 took a shot at forecasting the financial fallout from a variety of “severe natural catastrophes,” specifically “two major earthquakes, two tropical windstorm events, and two volcanic eruptions.”

Bye, bye Seattle

One of the volcanic assessments just happened to focus on Mount Rainier, the snow-covered peak to the southeast of Seattle through which so much of Alaska’s commerce funnels. Rainier was seen as something of a ticking time bomb with the potential to bury  “several major US airports and sea ports in tephra (volcanic rock fragments and particles). Tephra deposits are swept as far away as the east coast of Canada, impacting air travel following the eruption. In both cases, global temperatures are affected by the eruptions, leading to three years of climate abnormalities, global food shortages and soaring inflation.”

The $7.6 trillion costs of a Rainier eruption were judged to be four times the $1.9 trillion costs of a massive earthquake in Tokyo, one of the most densely populated places on the globe.

“The magnitudes of the chosen scenarios are thought to be towards the upper end of current scientific constraints,” they added, “but it is plausible that even larger magnitude events could occur….Volcanic eruptions can occur that are orders of magnitude larger than the Volcanic Explosivity Index (VEI) 6 events we model. There have been more than 60 known VEI 7 (‘super-colossal) eruptions in geological history and records of VEI 8 (‘mega-colossal) eruptions.”

The 1980 blast that tore the top off Washington’s Mount St. Helen was a VEI 4 event, according to the U.S. National Park Service, and although the St. Helens eruption is the largest to have taken place in the United States in more than 100 years, it is not even close to being the largest eruption in North America.

“The 1912 eruption of Novarupta in Katmai National Park and Preserve was about 30 times larger than St. Helens based on the volume of magma emitted…(and) the Novarupta eruption is itself small compared to the largest eruption at Yellowstone (2.1 million years ago),” according to the agency. “The Yellowstone Huckleberry Ridge eruption emitted 590 cubic miles (2,450 cubic kilometers of magma—approximately 10,000 times of what St. Helens erupted.”

Two years ago, researchers from the University of Leicester in the United Kingdom, reported for the first time that the Huckleberry Ridge eruption had been preceded by the even larger Grey’s Landing super eruption.

“The Grey’s Landing eruption enameled an area the size of New Jersey in searing-hot volcanic glass that instantly sterilized the land surface,” lead researcher Thomas Knott told the Geological Society of America. “Anything located within this region would have been buried and most likely vaporized during the eruption. Particulates would have choked the stratosphere, raining fine ash over the entire United States and gradually encompassing the globe.”

For too long, the authors of the Nature paper wrote, the risks inherent in such eruptions have been ignored.

Focus down, not up

“Over the next century, large-scale volcanic eruptions are hundreds of times more likely to occur than are asteroid and comet impacts put together,” they wrote. “The climatic impact of these events is comparable, yet the response is vastly different. ‘Planetary defense’ receives hundreds of millions of dollars in funding each year, and has several global agencies devoted to it.

“In September, NASA’s Double Asteroid Redirection Test (DART) mission will try to nudge an asteroid’s trajectory, testing capabilities for future asteroid deflection. That advance-preparation project will cost over $300 million. By contrast, there is no coordinated action, nor large-scale investment, to mitigate the global effects of large-magnitude eruptions. This needs to change.

“Although researchers have long known of the drastic impacts of large-scale volcanic eruptions, the likelihood of such an event has only recently been clarified.

“The recurrence rate of large eruptions can be determined by searching the long-term records for sulfate spikes, stemming from the gas released during globally significant events. In 2021, researchers looked at ice cores from both poles and identified 1,113 signatures of eruptions in the Greenland ice and 737 in Antarctica, occurring between 60,000 and 9,000 years ago. They found 97 events that probably had a climatic impact equivalent to that of a magnitude 7 eruption or greater. They concluded that magnitude-7 events happen about once every 625 years, and magnitude-8 events (also called super-eruptions) about once every 14,300 years. That’s more frequent than suggested by previous assessments – using geological records and statistical techniques – that found recurrence intervals of 1,200 years for magnitude 7 and 17,000 years for magnitude 8.”

Clearly it’s time to get the mainstream media busy mongering up some more fear about a big boom. Even if it were to happen faraway and unheard, it clearly holds the potential to cause even more global havoc than former President Donald Trump.