27th August, 1883, 10:02am local time. This was when Krakatoa last erupted – and what an astonishing event it was. I'm currently reading Krakatoa: The Day The World Exploded and it's a fascinating read. Allow me to share with you some quite astounding details of the event.
The final explosion (Krakatoa had been erupting since May, and seriously for a day) is reckoned to be the loudest sound in recorded history. It was heard over about 13% of the surface of the globe.
The air shockwave from the explosion circled the globe seven times. The sea waves were recorded as far away as the English channel.
Six cubic miles of rock were vaporized.
Sea waves1 were several and reckoned by many reports (and confirmed by the area they reached inland) to be somewhere around 120 feet high. A lighthouse was simply smashed off its base by a huge lump of coral (say about 600 tons) dredged from the deep. A ship was picked up out of harbour and dumped miles upriver inland, where it remained, providing a home for wildlife until the last remains rusted away in the 1980s.
Over 36,000 people were killed.
And of course there are many reports of other apocalyptic phenomena, e.g. constant St. Elmo's Fire among the shipping in the area, and rafts of pumice containing human skeletons washing ashore in Africa.
But equally as fascinating was the world's reaction to the event. It was the beginning of the global village – underwater cables had recently linked practically all parts of the globe, enabling messages to be sent in a matter of hours rather than weeks. Prior to this, for example, it had taken a full five days for folks in London to learn of the assassination of Lincoln – and that was fast! As well as reading about the eruption in the papers, it was the first time that folk realised that things happening nearly half a world away could have an effect locally – of course, the sunsets, which persisted for a period of years. And the shockwave circling the earth? Well that was picked up by many a European barograph – the latest gadgets of the time were causing a craze for amateur meteorology among fashionable Victorians. This is partly the reason why we are able to pinpoint the exact timeline of the eruption (the other reason is the barometric record of the gasometers in Batavia, 90 miles away from Krakatoa).
Tracking the path of Krakatoa's ejecta in the upper atmosphere also helped lay the foundations for the meteorology of today, and the data still yielded information on analysis well into the latter half of the 20th century.
Anyway, a fascinating read.
1. Sea wave, I read, is a preferred term for tidal wave. Of course almost all waves are sea waves, but then again almost all waves are tidal – funnily enough, except “tidal waves” which are caused by cataclysmic events. So there is a certain logic to preferring sea waves. Of course, the term tsunami fits even more succinctly.