Go on, take a guess. What’s the loudest sound in history? Maybe liftoff of the great Saturn V booster helping an Apollo mission to the moon. Or maybe a Deep Purple or Metallica concert. The detonation of a nuclear device? Good guesses, but not even close. According to scientists, the the eruption of Krakatoa, a volcano on Rakata Island in Indonesia, in 1883.
I’ve written about “the loudest sound ever made” before, but that was just a mere 270dB SPL.
Krakatoa was estimated to be 310dB SPL and could be heard 3,000 miles away!
Just for comparison, standing next to a jet engine is around 150dB.
In fact, the shock wave was so massive that it circled Earth four times in each direction before finally dissipating. For a full five days, weather stations around the world experienced spikes in pressure every 34 hours, which is about how long it takes for sound to circumnavigate the globe.
It delivered the equivalent force of a 200-megaton bomb — four times as powerful as the largest-ever thermonuclear explosion, Tsar Bomba, which up until then produced the loudest human-made sound in history.
It was estimated that 6 million cubic meters of soil was blown into the air. In fact, summer temperatures in the northern hemisphere fell by an average of 0.4 °C (0.72 °F) in the year and the sky took on an eerie red glow following the eruption.
Half the crew of the ship 40 miles away had ruptured ear drums, so this wasn’t something that you wanted to experience too closely.
You can read more Krakatoa here, but the point is that loud sounds are nothing to mess around with. According the an article in fivethirtyeight, “Humans exposed to infrasounds above 110 decibels experience changes in their blood pressure and respiratory rates. They get dizzy and have trouble maintaining their balance. In 1965, an Air Force experiment found that humans exposed to infrasound in the range of 151-153 decibels for 90 seconds began to feel their chests moving without their control. At a high enough decibel, the atmospheric pressure changes of infrasound can inflate and deflate lungs, effectively serving as a means of artificial respiration.”
Yes, you can even die from super high audio levels, so keep those studio monitor levels under control.
If you want to get a feel for what the shock wave at Krakatoa was like, here’s a video of a small volcanic eruption in Papua, New Guinea.
