It is estimated that about 5 to 10 volcanoes worldwide are capable of producing a super-eruption that could catastrophically affect global climate. One of these volcanoes hides below the waters of Lake Toba in Sumatra and has caused two super-eruptions in the last million years. But when will the next one be? Will there be any warning signs?
Click here for original story, The silent build-up to a super-eruption
Source: Phys.org