Tuesday, August 26, 2008

125 years ago today

125 years ago, the entire world shook. Almost literally.

On Aug 26-27, 1883, the volcano Krakatau/Krakatoa blew it's lid. It had simmered for several months, spitting out ash and smoke, but nothing like today. Krakatoa is a volcano island sitting between Java and Sumatra in the southeast Asian Indonesia.

Why is some volcano eruption 125 years ago important? Listen to the effects around the world:
  • The volcano eruption had the force of 200 megatons of TNT, roughly equivent to 13,000 times the force of the "Little Boy" used in Hiroshima, Japan in WWII
  • The sound of the explosions (actually at 10:20am on Aug 27 1883) were so loud, they were measured at 183 dB 100 miles away. Let me put this into perspective: A jet engine at 100 meters produces about 110-140 dB. This was 100 miles. 134 dB is supposedly the threshold of pain. Anyone within 100 mile radius of the explosion would have not only heard the explosion, but would have lost their hearing (at least maybe temporarily)
  • The blast was audible in Perth, Australia, 2200 miles away, and also the island of Rodrigues, nearly 3000 miles away (and 4 hours after the event). The Guinness Book of World Records reports that the blast was heard on over 1/13 of the surface of the earth.
  • The pressure shockwave from the final blast was measured on barometers all over the world. In fact, the wave was measured to circle the globe atleast 7 times, days after the event.
  • According to an official Dutch count (Indonesia being a Dutch colony at the time), the eruption and resulting tsunamis killed 36,417, however unofficial counts place the death toll somewhere around 120,000. These tidal waves were reported anywhere from 100-130 feet high.
  • In 1884, the year following the eruption, average temperatures around the globle dropped 2.16 degrees F due to ash in the upper atmosphere. The blast shot ash up to 50 miles high
  • The ash in the upper atmosphere would have caused spectacular blood red sunsets all around the globe for years. The yellow light of the sun cutting through the earth at an angle at sunrise/sunset usually causes the reddish color, however it would have been amplified by the ash. It's thought that Edvard Munich's painting "The Scream" was directly influenced by the eruption, despite the fact that he was in Norway.
The power and effects of an eruption like this leave me in awe.

More info: http://www.wired.com/science/discoveries/news/2008/08/dayintech_0826

1 comment:

Bek said...

That is INSANE. I hope it never erupts again. I never would have known without this post. Could you imagine living in that time, wondering what on earth was going on?