Annual average temperatures in the Northern Hemisphere dropped by about 1 °C during one of the most powerful eruptions of the 19th century. Now, nearly 200 years later, scientists have identified the ‘mystery volcano’ that cooled Earth’s climate after its 1831 eruption.
In their research published Monday in the journal Proceedings of the National Academy of Sciences, scientists have linked the 1831 eruption to an island volcano in the northwestern Pacific Ocean.
The ‘mysterious volcano’ was Zavaritsky, also spelled Zavaritsky. It is located on Simushir Island, part of the Kuril Islands archipelago – a territory disputed by Russia and Japan. According to their analysis, the last eruption from Zavaritsky occurred in 800 BC.
Although researchers knew the year of this historic eruption, they were unable to pinpoint the volcano’s location until recently when they sampled ice cores in Greenland.
The eruption occurred during the last gasp of the Little Ice Age, considered one of the coldest periods in Earth’s history over the past 10,000 years. As part of their research, scientists looked at layers of the core, which were deposited between 1831 and 1834, to examine sulfur isotopes, small volcanic glass fragments, and ash particles.
To map the particles’ trajectories, the researchers analyzed radioactive dating, geochemistry and computer modeling.
“For many of Earth’s volcanoes, particularly those in remote areas, we know very little of their explosive history,” said study lead author Dr. William Hutchison, a principal research fellow in the School of Earth and Environmental Sciences at the University of St. Andrews in Britain and lead author of the study. There is poor understanding”.
Since Zavaritsky is located on an extremely remote island between Japan and Russia, “no one lives there and historical records are limited to a handful of diaries of ships that passed by these islands every few years,” Hutchison said via email. from told CNN.
According to the latest study, no one previously thought that Zavaritsky was behind the 1831 eruption because little was known about its activity during the 19th century. Instead, they considered other volcanoes, particularly those located closer to the equator, such as Babuyan Claro Volcano in the Philippines.
