Nearly two centuries ago, an explosive volcanic eruption in 1831 cooled the Earth's climate, but the location of the "mystery volcano" remained unknown.
Now, scientists have identified the culprit: the Zavaritskii volcano on Simushir Island in the Kuril Islands, located between Russia and Japan.
Greenland Ice Links Zavaritskii to 1831 Climate Cooling
This eruption was one of the most powerful of the 19th century, releasing massive amounts of sulfur dioxide into the atmosphere.
According to CNN, the volcanic activity lowered Northern Hemisphere temperatures by about 1 degree Celsius (1.8 degrees Fahrenheit), causing global cooling during the tail end of the Little Ice Age — a centuries-long period of cooler temperatures that spanned the early 1400s to 1850.
Researchers cracked the case by analyzing ice cores from Greenland. These cores, which contain layers of ancient ice, held traces of sulfur isotopes, ash, and microscopic volcanic glass shards from the eruption.
By comparing these findings with geochemical samples from known volcanic regions, the team pinpointed the source. Their analysis linked the chemical signatures to Zavaritskii, which had not been suspected because of its remote location and sparse historical records.
Zavaritskii, part of the uninhabited Simushir Island, last erupted in 800 BCE, according to previous records.
However, the 1831 eruption was catastrophic, forming the caldera that dominates the volcano today. The size and impact of the eruption were comparable to that of Mount Pinatubo in 1991, which similarly cooled global temperatures.
Scientists Call for Better Monitoring After Solving 1831 Eruption Mystery
Dr. William Hutchison, a volcanologist at the University of St. Andrews and the study's lead author, described the discovery as a "genuine eureka moment."
The ash samples from the Greenland ice cores and Zavaritskii's caldera matched perfectly, confirming the volcano as the source, ScienceAlert reported.
Further analysis of the caldera's sulfur isotopes and tephra deposits placed the eruption within the early 19th century.
The global impact of the 1831 eruption was severe. The cooling caused by the volcanic ash led to crop failures and widespread famine in regions like India, Japan, and Europe.
While researchers continue to study how much of the devastation was due to volcanic cooling versus socio-political factors, the findings underscore the significant role that remote volcanoes can play in shaping global climate.
Dr. Hutchison emphasized the importance of monitoring isolated volcanoes like Zavaritskii to prepare for future large-scale eruptions. "We need to consider how to coordinate an international response when the next big eruption happens," he said.
The identification of Zavaritskii not only solves a centuries-old mystery but also highlights the ongoing need for better monitoring of remote volcanic activity. These efforts are vital to understanding and mitigating the global impacts of future eruptions.
