KRAKATOA! Just the name is enough to terrify the residents of the islands of Java and Sumatra, who live in the shadow of one of the most lethal volcanoes in history.
Ever since the mammoth eruption of 1883, which blacked out the sky and was heard more than 2,000 miles away, Krakatoa, which stands in the Sunda Strait between Sumatra and Java, has been shorthand for a disaster of Biblical proportions.
Just as the 79AD eruption of Vesuvius, which obliterated the residents of Pompeii and Herculaneum, horrified the ancient world, so Krakatoa is the destructive volcano of the modern age – shooting out ash, pumice stone, steam and volcanic gas.
Just like Vesuvius, it produces a deadly ‘pyroclastic flow’ – hot gas and volcanic matter reaching temperatures of 1,000C and flying at 430 mph, killing everything in its path.
Lava streams down from the volcano Anak Krakatau – meaning Child of Krakatoa – during the eruption as seen from Rakata island in South Lampung, Indonesia
In fact, the weekend’s deadly volcano – which has been active for six months, pouring out lava and shooting fire, debris and smoke nine miles into the air – is Anak Krakatau, which means Child of Krakatoa (the name Krakatoa, of unknown origin, can be spelt in more than 20 different ways).
It was formed in 1927, inside the caldera – or cauldron-like hollow – created by that vast 1883 explosion of the original Krakatoa volcano.
Active volcanoes are forever changing shape: the Krakatoa eruption in the 19th century itself blew away two-thirds of the island of Krakatoa, including three peaks of old volcanoes that had been there before.
As the people of the region mourn their losses this week, they will reflect on the latest deadly harvest from this malign behemoth, which has been erupting for thousands of years. There was a particularly vicious eruption in 535AD-536AD – said to be the worst year in human history, partly thanks to Krakatoa’s atmospheric dust veil causing crop failures, famines and appalling weather across the world. Throughout the Middle Ages, Krakatoa is thought to have erupted roughly once a century.
It isn’t yet clear exactly how Saturday’s tsunami, which has killed more than 220 people, was triggered, but volcanologists are near certain that it was set off by volcanic activity at Anak Krakatau. It’s thought that the eruption has either blasted off a side of the volcano into the sea, generating the massive waves, or the eruption has shifted a huge movement of sediment on the sea floor, in turn creating those waves.
Either way, the eruption brings up heart-stopping memories of the Krakatoa eruption – or series of eruptions – from August 26 to 27, 1883, which are thought to have killed more than 35,000 people.
Krakatoa had been experiencing lesser eruptions – worryingly like the current one – since May 20, 1883. And then, at the end of August, the big one came.
The combined eruptions produced the equivalent of 200 megatons of TNT – that’s 13,000 times the explosive effect of the nuclear bomb that flattened Hiroshima in 1945 during the Second World War.
The 1883 eruption was heard nearly 3,000 miles away to the west near Mauritius, and more than 2,000 miles to the south-east in Alice Springs, Australia. Anyone within ten miles of the volcano was said to have gone deaf.
‘Those who weren’t killed by the intense heat would have been sandblasted to death,’ says Dr Dave Rothery, from the Department of Earth Sciences at the Open University. ‘It was hot enough to carbonise everything in its path.’
The effects were felt across the world for years. Skeletons of Indonesians were found floating on fragments of detonated pumice a year after the eruption, washed up on the east coast of Africa. As skies darkened across the world thanks to the ash-filled atmosphere, global temperatures dropped by 1.2C for a year.
Fire and ash: An aerial view of the volcano on Sunday after the eruption which sent a wall of water slamming into the shore, in a natural disaster which has killed 222 people
The eruption played havoc with the world’s climate for five years. Some experts have even suggested the blood-red sky in the background of Edvard Munch’s famed 1893 picture The Scream was created by the after-effects of the eruption as far afield as Norway, where it was painted.
Just like at the weekend, the 1883 eruption had massive tidal effects, with the wave travelling around the planet three times, and ash thrown 50 miles into the air. The waves reached 130 feet high, tossing 600-ton chunks of coral reef on to the coast.
Because the eruption happened in the modern age, after the invention of Morse code and the underwater telegraph cable, it was one of the first international media events, reported almost immediately.
First-hand accounts from survivors in the region swept across the world, including the quarry manager who told how a wave had plucked him from the top of an office block and swept him into the jungle, alongside a crocodile.
He leapt on the back of the croc, which carried him for two miles before dropping him off in the rainforest.
If there’s any consolation for modern Indonesia – and there is little at the moment – the current eruption was dwarfed by the 1883 event, which killed 36,417 people and destroyed or damaged nearly 300 villages.
Just like the residents of Naples living in the shadow of Vesuvius, the Indonesians have grown used to the eruptions of Anak Krakatau, which has blown in 2009, 2010, 2011 and 2012.
With every eruption, Anak Krakatau has grown spookily taller, adding on 250 feet since 2011.
What is especially chilling is that Krakatoa is directly – and fatally – just above the area where two of the Earth’s tectonic plates making up the planet’s subterranean shield meet. One of the tectonic plates is being pulled beneath the other, at a rate of six centimetres a year.
The Earth’s protective crust, it is thought, is particularly shallow here – meaning it is lethally easy for an eruption to burst forth into the atmosphere, to devastate the region around with deadly effect.