Global Volcanic Disaster: Could the next massive eruption bring global disaster?

The eruption of Mount Tambora in 1815 was a cataclysmic event that profoundly altered the world, ushering in the infamous “year without a summer.”
This Indonesian volcano’s eruption, the most powerful in recorded history, released an immense plume of sulfur dioxide into the atmosphere, cooling the planet, devastating crops, and triggering widespread starvation and disease.
More than two centuries later, scientists warn that another massive eruption is not a matter of “if,” but “when,” reported CNN quoting Markus Stoffel, a climate professor at the University of Geneva.
Geological evidence suggests a 1-in-6 chance of such an eruption occurring this century.
Massive volcanic eruptions propel sulfur dioxide into the stratosphere, forming aerosol particles that scatter sunlight and cool the Earth.
When Mount Pinatubo erupted in 1991, it released approximately 15 million tons of sulfur dioxide, cooling the planet by about 0.5°C for several years. More ancient eruptions, like Tambora in 1815 and Samalas in 1257, likely caused cooling of up to 1–1.5°C.
These cooling effects, however, are not uniformly distributed. Historical records indicate that the Okmok eruption in Alaska in 43 BC may have lowered temperatures in southern Europe and northern Africa by as much as 7°C.
A warming world faces a colder threat
The next massive eruption would occur in a world already altered by the climate crisis.
According to CNN, the impacts of such an eruption might be even more severe than in 1815, said Michael Rampino, a professor at NYU studying volcanic eruptions and climate.
As global warming accelerates atmospheric circulation and alters ocean dynamics, the cooling effects of an eruption could be amplified. This could lead to disruptions in rainfall, including critical monsoon systems in Asia and Africa.
Moreover, climate change may itself increase volcanic activity. Melting ice caps reduce pressure on magma chambers, potentially triggering eruptions. Extreme rainfall, another byproduct of a warming climate, can infiltrate volcanic systems and react with magma, further increasing the likelihood of eruptions.
Economic and human toll
The immediate impact of a massive eruption would be devastating for those living near active volcanoes. Long-term effects include significant disruptions to global food supplies as colder temperatures and altered rainfall patterns impact key agricultural regions, such as the US, China, and Russia.
A recent analysis by Lloyd’s of London estimated that an eruption comparable to Tambora could cause economic losses exceeding $3.6 trillion in the first year alone.
While some may view volcanic cooling as a temporary relief from climate change, scientists caution against such optimism. The cooling effects are short-lived, and the world would quickly return to its pre-eruption state.
Although it is impossible to predict when and where the next massive eruption will occur, regions like Indonesia and Yellowstone in the US remain under close observation. Stoffel emphasised the need for preparedness, assessing risks, conducting stress tests, and developing plans for evacuations, food security, and aid distribution.
“The probability of a massive eruption may be small, but it’s not negligible,” Stoffel said. Currently, the world lacks sufficient plans to handle the potential fallout from such a disaster. “We’re just at the beginning of getting an idea of what could happen”, Stoffel added.