Study Finds Toba’s 74,000-Year-Old Eruption Cooled Earth Only 0.5C for Under 2 Years
Updated
Updated · Ars Technica · Aug 7
Study Finds Toba’s 74,000-Year-Old Eruption Cooled Earth Only 0.5C for Under 2 Years
3 articles · Updated · Ars Technica · Aug 7
Summary
Lake-core evidence from the Kenya-Tanzania border suggests the Mount Toba eruption caused less than two years of climate disruption and only about 0.5C of cooling.
Jinheum Park and colleagues say that finding undercuts the long-standing idea that the eruption nearly wiped out early humans through a prolonged volcanic winter.
The team argues earlier estimates swung wildly because Toba’s sulfur output was uncertain, making computer models range from near-extinction scenarios to minor disruption.
Their explanation is that extremely large eruptions can produce heavier sulfate aerosols that fall out faster, limiting how long they reflect sunlight and cool the planet.
The study also highlights why many seafloor and lake mud records struggle to capture 1-to-3-year volcanic shocks: sediments mix signals from multiple years.