Impressive current view of Anak Krakatau volcano - growing inside the caldera created by the 1883 explosion of Krakatoa.

How Weather Created The Vikings

You may have heard of Krakatoa, a giant volcanic explosion which caused the year without a summer. But did you know something equally giant happened in 536 CE? A vast cloud of dust darkened the sky, likely caused by a combination of cataclysms such as comets or meteorites, plus at least one volcanic eruption. Whatever happened caused lower summer temperatures in the northern hemisphere for the next fourteen years!

The added cold and darkness devastated Scandanavia. In the Uppland region, for instance, we know nearly 75% of villages were abandoned during this period. And the legend of Ragnarok may have been inspired, or embellished, during this period; the end of the world is supposed to start with Fimbulwinter, a deadly time when the sun turns black and the weather bitter and changeable – just like the harsh years after 536 CE. 

Scholars note that when Scandanavian society eventually rebounded, their culture was much more war-centered, with men and women alike celebrating the virtues of fearlessness, aggression, and physical prowess. Local rulers were constantly seizing and defending abandoned territory, fighting for good farmland and good fishing territory. Graves are suddenly filled with weapons and shields. A militarized society arose, which would one day be known and feared across the continent.

At 10:02 AM on August 27th, 1883, a volcanic island in modern day Indonesia called Krakatoa erupted. The blast sent shockwaves across the ocean, triggering tsunamis that destroyed the coast of Java and Sumatra. The sound was so loud it was heard 3000 miles away.

As Aatish Bhatia notes in this recent article:What we’re talking about here is like being in Boston and clearly hearing a noise coming from Dublin, Ireland.

Barometric readings at the time clocked the sound pressure at 172 decibels ONE HUNDRED MILES AWAY from the island.

Here’s a handy reference:

  • Using a jackhammer – 100 decibels
  • Human threshold for pain – 130 dB
  • Standing next to a jet engine – 150 dB

And the scale is logarithmic - so a 10 dB increase doubles the loudness.

The Sound That Shook The World

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. 

4 Nightmare Apocalypses Humanity Forgot Were Possible

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.


August 27, 1883: Krakatoa erupts.

The volcanic island of Krakatoa, located between the islands of Java and Sumatra, lay dormant for at least two centuries, before a passing European ship reported seeing enormous clouds of ash and dust rising from the area in May of 1883. Over the following months, volcanic activity in the region intensified, before reaching an apex on August 26th and 27th of that same year.

Four enormous explosions took place on August 27th, resulting in the destruction of at least two-thirds of the island. The sound produced by the eruption was so loud that it could be heard 3,000 miles away (on the island of Rodrigues in the Indian Ocean, the sound was initially thought to be the “roar of heavy guns”). The black clouds of ash spewed into the air by the volcano rose fifty miles high. Each of these colossal explosions was accompanied by tsunamis, which single-handedly killed off a large fraction of the (official) death toll, which was estimated at 36,000. Pyroclastic flow reached neighboring islands (including Sumatra) and wiped out vegetation, villages, and people. For months around the world, sunsets glowed unusually brilliant colors as a result of the gases emitted by the volcano; one British poet, Gerard Manley Hopkins, described this phenomenon:

…more like inflamed flesh than the lucid reds of ordinary sunsets… it bathes the whole sky, it is mistaken for the reflection of a great fire.

It is also sometimes theorized that Edvard Munch’s The Scream also depicts the after-effects of Krakatoa, similar as to what was described by Hopkins.

In modern terms, the eruption of Krakatoa is estimated to have had a yield of around 200 megatons; to put things into perspective, the “Fat Man” device detonated over Nagasaki had a yield of 21 kilotons, while Tsar Bomba, the most powerful nuclear weapon ever detonated, had a yield of 50 megatons.