Volcanoes may not, generally speaking, take as many lives as earthquakes and floods – 92,000 in the last 100 years. But the greatest of volcanic outbursts can bring about a global freeze, worldwide harvest failure and unimaginable loss of life. Around 74,000 years ago, a colossal super-eruption of the Toba volcano in Sumatra may have brought our race to the brink of extinction, while as recently as 1783, famine caused by the climatic impact of an eruption of Iceland’s Laki volcano may have led to as many as six million deaths worldwide.
There are at least 1,500 active volcanoes around the world, of which around 50 erupt every year. To most people the idea of a volcano erupting equates to the outpouring of red-hot lava, but this is rarely a killer.…