Sunday, August 13, 2006

Anorak Krakatoa

Woolly Days is reading 'Krakatoa' by Simon Winchester which is a very readable account of the massive volcano which erupted there in 1883. This event plunged the world into darkness for many months and was the first worldwide event that received mass communication after the world was brought together by telegraph cable. The mountain and the entire island was destroyed by the volcano but a new island called Anak Krakatoa (child of Krakatoa) is building up very rapidly to take its place.

The 1883 eruption ejected more than 25 cubic kilometres of rock, ash, and pumice and generated the loudest sound ever historically reported — the cataclysmic explosion was distinctly heard as far away as Perth in Australia (approx. 3100 km distant), and the island of Rodrigues near Mauritius (approx. 4800 km away). Near Krakatoa, official records state that 165 villages and towns were destroyed and 132 seriously damaged, at least 36,417 people died, (plus many more who wouldn’t have been captured by the record) and many thousands were injured by the eruption, mostly in the tsunamis which followed the explosion.

The eruption destroyed two-thirds of the island of Krakatoa. New eruptions at the volcano since 1927 have built Anak Krakatau. The impacts of a possible earlier quake in approximately 535 AD has been blamed for everything from the fall of the Roman Empire and the darkness of the Middle Ages in Europe to the rise of Islam. Most of Indonesia was well and truly Islamised by the 1880s even though the Dutch had ruled it for nearly three hundred years mainly through its proxy the VOC The Dutch East Indian Company, a company which went along way to invented modern international capitalism. On 26 August 1883 after many months of threatening to blow its top, Krakatoa finally gave up its cataclysmic secret and spewed a toxic mix of pumice and ash. The following day it exploded completely. There were four explosions in all, each of which was accompanied by a tsunami. Hot gas, ash and rock (called pyroclastic flow) were strewn across a large area of Sumatra and Java. Ash was propelled to a height of 80kms. Smaller eruptions continued through to February 1884. In the aftermath of the eruption, it was found that the island of Krakatoa had almost entirely disappeared, except for the southern half of Rakata cone cut off along a vertical cliff, leaving behind a 250 m-deep caldera.

Ships as far away as South Africa rocked as tsunamis hit them, and bodies were found floating in the ocean for weeks after the event. There are numerous documented reports of skeletons floating across the Indian Ocean on rafts of volcanic pumice and washing up on the east coast of Africa, up to a year after the eruption. Some land on Java was never repopulated; it reverted to jungle and is now the Ujung Kulon National Park. The eruption was 13,000 times stronger than the Hiroshima bomb. The pyroclastic flows caused several cubic kms of material to enter the sea, displacing an equally huge volume of seawater.

The eruption produced erratic weather and spectacular sunsets throughout the world for many months afterwards, as a result of sunlight reflected from suspended dust particles ejected by the volcano high into Earth's atmosphere. The area around Java is now known as Lady Bull because of its fiery nature. In the year following the eruption, global temperatures were lowered by as much as 1.2 degrees Celsius on average. Weather patterns continued to be chaotic for years, and temperatures did not return to normal until 1888.

Because the underground telegraph cable had recently been laid all the way to Australia, this was massive news quickly across the planet. The Javan name "Krakatau" was turned into the more dramatic sounding Krakatoa and then Hollywood moved the island to east of Java. But Anak Krakatau remains where its parent once stood serenely on the west coast of Java near the coast of Sumatra. But serene isn't the right word. It is growing every day and fast. Hormones, perhaps? The Sunda strait remains a geological time bomb.

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