Worldize - Mysterious Sounds of The Sea

Worldize - Mysterious Sounds of The Sea

Worldize - Mysterious Sounds of The Sea

The oceans and what swim in their depths are covered in mystery. In this story, we talk about the mysterious underwater sound known as Julia.


Created by the sound design studios of Badlands Sound.



From Badlands Sound, You are listening to Worldize - The sounds of our world. I am your host Luke Farroh. This story is about the strange sounds underneath our oceans.


The majority of the oceans remain unexplored, leading to mystery and many unanswered questions. We know so little about our oceans that new species are often described as alien. Over the years, agencies throughout the world have been reporting strange sounds recorded with underwater microphones known as hydrophones.


Let's dive into the sonic mystery underneath our oceans.


In the late 90s, the US National Oceanic and Atmospheric Administration known as NOAA, recorded an odd sound beneath the ocean off Antarctica's coast known as "Julia" What you will listen to now is one of the famous mysterious underwater sounds known as "Julia."


(Sound of Julia)


Despite the friendly name it's been given, it's nothing short of terrifying. Robert Dziak is one of the Principal Investigators for the Acoustics Research Group. We were able to email him and clear up a couple of mysterious questions about the sound and how it got its name. "The signal was named "Julia" after the data analyst that found the first one. It stands out because of the clear harmonic tones of the signal," says Robert.

The sound was a very low-frequency range from 40 hertz and decreasing over time to about 10 Hz at the end. It was needed to speed up 16 times its original speed to be audible to human ears. The sound was recorded with a network of hydrophones known as the Pacific Autonomous Array. It was so loud that it could be heard over the entire array, reaching at least 3,000 miles and at a depth of 23,000 feet below sea level.


"We don't have a very accurate estimate of the source strength, but it's likely in the 190-200 decibel range." says Robert. That's 80 decibels louder than a sonic boom from a fighter jet. Or the same loudness as a rocket taking off.



This sound has appeared in many discussions and videos online, and it is estimated that millions of people have heard Julia. With so many people listening to it on the internet, it speculates what the source could be, from undiscovered sea monsters to forgotten cold war testing sites.


It didn't take much time for researchers to believe the sound of Julia was no more than a large iceberg falling and crashing onto the sea floor. We don't know why the NOAA closely monitored this area in the late 90s. Still, their hydrophones have recorded many exciting and mysterious sounds over the years, many believed to be icebergs deep beneath the ocean, while others remain unexplained.


The oceans and what may swim in their depths are covered in mystery; agencies will continue to record and monitor these sounds gaining more information to learn more about our world.




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