August 27, 1883: the earth makes the loudest noise, louder than any it has made since. A volcano on Krakatoa was erupting and it did so with a bang. Literally – the sound was so loud, it was heard across a thirteenth of the globe. If you were in Washington, DC and heard a noise coming from Philadelphia, that would be incredible. But those cities are just 140 miles apart. Krakatoa was heard 3,000 miles away. It would be like if you were in Washington, DC and heard a noise coming from Dublin!
A barometer at the Batavia gasworks (100 miles away from Krakatoa) registered the ensuing spike in pressure at over 2.5 inches of mercury. That converts to over 172 decibels of sound pressure. A jackhammer is about 100 decibels, and a jet engine is about 150 decibels. To register as 172 decibels, 100 miles away? People’s eardrums must have been shattering.
Around 2,000 BC, the city of Akrotiri – built upon an island now known as Santorini, in the southern Aegean Sea – was a bustling sea port. They had multi-story dwellings, their interiors covered in elaborate frescoes, paved roads, advanced metalworking, indoor running water, and flush-toilets. We’d suspect that the natives of Akrotiri were time travelers, if not for the fact that they built their highly advanced settlement right beneath the most destructive volcano the world has seen in the last 10,000 years.
In 17th-century BC, a magnitude 7 earthquake reduced the town to rubble, then smacked the ruins with a few 30-foot tidal waves for good measure. There’s archaeological evidence that the survivors had begun cleaning up and rebuilding… when the island’s volcano, Thera, erupted.
The eruption was four to five times more powerful than Krakatoa, releasing hundreds of atomic bombs worth of energy in less than one second. When the dust finally settled, it perfectly preserved the ruins of the city for modern-day archaeologists to gawk at.
If widespread theories are correct, then Thera may have been Plato’s inspiration for the Atlantis myth – a destroyed island, a lost, highly advanced civilization – but, if anything, the myth downplays the reality. It didn’t just sink beneath the sea, it took a killer three-hit combo from nature, all but simultaneously crumbling, drowning, and exploding.
Krakatoa, the volcano that exploded in 1883 and around the world lead to the re-coloring of the sky that is visible in the famous painting The Scream by Munch, from above. The shock wave of the explosion was felt around the world, and even the fifth time it went around the earth it was still measurable. The explosion is also considered to be the loudest sound ever heard in modern history.
Large, explosive volcanoes, like the 1883 eruption of Krakatoa, can temporarily alter global climate by injecting sulfurous gases into the high atmosphere. These aerosols cool Earth by slightly shading its surface, reflecting back to space some sunlight that would otherwise shine on it. The way volcanic aerosols reflect light produces vivid red sunsets.
The red skies in Edvard Munch’s famous 1893 painting The Scream are now thought to reflect the eerie twilights seen in Norway for months after Krakatoa’s eruption.