Toba catastrophe theory
The Youngest Toba eruption was a supervolcanic eruption that occurred around 75,000 years ago at the site of present-day Lake Toba in Sumatra, Indonesia. It is one of the Earth's largest known explosive eruptions. The Toba catastrophe theory holds that this event caused a global volcanic winter of six to ten years and possibly a 1,000-year-long cooling episode.