The Volcano That Shook The World: Are We Ready for the Next Tambora?

In 1815, Mount Tambora in Indonesia unleashed the most powerful volcanic eruption in recorded history. The explosion hurled vast quantities of sun-blocking particles into the atmosphere, plunging the planet into a temporary chill that reshaped history. The aftermath became known as the “Year Without a Summer,” a global catastrophe marked by plunging temperatures, crop failures, widespread famine, and the spread of cholera. The death toll reached tens of thousands, and some even credit the eerie, cold weather for inspiring Mary Shelley to pen Frankenstein during a frigid summer in Switzerland.

Although numerous volcanoes have erupted since, none have matched the magnitude of Tambora. More than 200 years later, scientists warn that another massive eruption is not just possible but likely. Markus Stoffel, a climate expert at the University of Geneva, estimates a 1-in-6 chance of such an event occurring this century. Unlike 1815, the next eruption would strike a vastly changed world—one grappling with a warming climate and a much larger population.

A Recipe for Chaos

The next massive volcanic eruption could wreak unparalleled havoc. “It will cause climate chaos,” Stoffel warns, emphasizing humanity’s lack of preparation for such an event. While volcanoes have long played a role in shaping our planet, their power to influence climate can be devastating.

When volcanoes erupt, they release a mix of lava, ash, and gases, including carbon dioxide. But for climate scientists, the focus is on sulfur dioxide, a gas capable of creating sun-reflecting aerosols high in the stratosphere. These aerosols can scatter sunlight, cooling the planet for years. For instance, Mount Pinatubo’s 1991 eruption in the Philippines, though smaller than Tambora, cooled the Earth by 0.5°C for several years.

Reconstructing the impacts of ancient eruptions, like Tambora or the 1257 Samalas eruption, shows that these events cooled the planet by 1°C or more, disrupted monsoon patterns, and altered rainfall systems. The stakes are even higher today in a world already destabilized by climate change.

A Warmer World, Bigger Impacts

Paradoxically, the warming climate could amplify the effects of a massive volcanic eruption. Faster atmospheric circulation could scatter aerosols more efficiently, intensifying the cooling effect. Meanwhile, warming oceans could trap cooler surface temperatures, exacerbating weather disruptions.

Climate change could also trigger more frequent eruptions. Melting glaciers reduce pressure on magma chambers, increasing the likelihood of eruptions, while extreme rainfall can penetrate deep underground, interacting with magma to spark activity.

A Disaster in Waiting

The immediate impact of an eruption would be devastating. Around 800 million people live within 60 miles of active volcanoes, with cities like Naples, near Italy’s Campi Flegrei, at risk of annihilation. The longer-term consequences could be equally dire. A global temperature drop of even 1°C could devastate agriculture, trigger food shortages, and ignite geopolitical tensions.

Historical examples highlight the danger: the eruption of Okmok in Alaska in 43 BC caused regional cooling of up to 7°C, severely impacting agriculture in southern Europe and northern Africa. Modern analyses suggest a Tambora-like event could cause over $3.6 trillion in economic losses in the first year alone, with no lasting relief from climate change once the cooling dissipates.

Preparing for the Unpredictable

While predicting the exact timing and location of the next massive eruption is impossible, scientists urge proactive planning. Potential hotspots include Indonesia and Yellowstone in the U.S., both long overdue for significant activity. Stoffel advocates for comprehensive preparation, from evacuation strategies to securing global food supplies.

The probability of such an event may seem low, but it’s far from negligible. “We’re just at the beginning of understanding what could happen,” Stoffel said. The question is not whether humanity can prevent the next Tambora, but whether we are ready to face it.