Scientists discover a mysterious volcano whose eruption shocked Earth’s climate 200 years ago

In 1831 our planet experienced one of its most dramatic moments. A volcano, unknown until recently, erupted with such force that it darkened the skies and lowered temperatures by about 1°C across the Northern Hemisphere. The impact was devastating: lost crops, famines in Europe, India and Japan, and millions of people forced to deal with hunger and desperation. For almost two centuries, the identity of the person responsible remained shrouded in mystery. Today, thanks to a scientific investigation, we know that the volcano is the culprit Zavaritskiilocated on the remote island of Simushirin the Kuril Islands, between Russia and Japan.

The Zavaritskii volcano has never been monitored as it deserves, due to its isolated location and the absence of inhabitants on the island of Simushir. For years, the 1831 eruption was incorrectly attributed to tropical volcanoes. The turning point came thanks to the analysis of Ice cores taken in Greenlandwhere tiny ash particles were trapped.

The doctor William Hutchisonone of the scientists who led the study, recounts the emotion of the moment in which the samples of volcanic ash, compared with the rocks from the island of Simushir, revealed a perfect match:

It was a thrilling moment, a real eureka. The data was incredibly clear.

The Zavaritskii volcano has been identified as responsible for one of the most powerful eruptions of the 19th century. The enormous amount of sulfur dioxide released into the atmosphere caused global cooling, accentuating the already harsh effects of the Little Ice Age.

The global consequences of an “invisible” volcano

The effects of the disaster were immediate and devastating. The colder and drier climate seriously compromised harvests, leading to famines that affected millions of people, as Hutchison explains:

The social repercussions were immense, and understanding the extent to which climate played a role in these tragedies is one of the objectives of current research.

But how is it possible that an event of this magnitude remained forgotten for so long? The answer lies in the geographic isolation of Simushir, an island so remote that not even travelers of the time could accurately document its effects. The only traces, in addition to the ice, were found in the logbooks of some sailors who passed near the archipelago.

Zavaritskii: a warning for the future

Zavaritskii’s story offers us a valuable lesson. The most dangerous volcanoes are not always the most famous or monitored ones. Many, like Zavaritskii, are located in remote and poorly accessible regions. This makes it difficult to predict and mitigate the effects of future eruptions, as Hutchison warns:

We don’t have a truly effective international system for managing large-scale eruptions. It’s something we need to work on as a scientific community and as a society.

Volcanic eruptions can change the course of history, as the one in 1831 demonstrates. With climate change already underway, similar episodes could have even more dramatic effects on an increasingly vulnerable world.