The South Pacific Drone Zone

You know what sucks? Manmade noise pollution. Swelling mass acoustics have some pretty miserable side effects, not least that the late-night semis screaming down the Brooklyn-Queens Expressway, horns ablazing, will often rouse me from my padded first-world slumber. Now that we've maybe surpassed the symbolic 7 billion human barrier, too, I'll hazard the guess that from here on out, things are just going to get noisier.

If for whatever reason you're fixing to pinpoint the loudest, most unrelentingly dinny place on Earth that's populated with humans, you'll want to look toward the usual suspects – New York City, Cairo, Mumbai, Chicago, and on and on. But if you're looking for something a bit more organic, a bit slower and bellowing and mysteriously droo(oo)ning, you'll want to board a ship and head due west from the southern tip of South America.

Tectonically, this remote region is a patchwork. The Antarctic, Nazca and Pacific plates all converge here. Even better, four of modern history's unaccountable terra-acoustical blasts have all eked from its depths.

Welcome to the other loudest fucking place on earth.

The VENTS Program of the National Oceanic and Atmospheric Administration's Acoustic Monitoring Project has been using various autonomous underwater hydrophones and the U.S. Navy SOund SUrveillance (SOSUS) network since 1991 to listen closely for these sorts of hydroacoustic phenomena, the sources of which are often unknown, despite some speculation.

To give you an idea of what the combined amp potential of (old) Dylan Carlson and Joe Preston could never touch, below are NOAA's field recordings of those four rumblings traceable to the South Pacific Drone Zone. Keep in mind that most played out slowly, so the audio on a select few has been sped up. Go ahead and put on your headphones now.

NOAA picked up this ultra-low frequency tone in 1997 at around 15° 0′ 0″ S, 115° 0′ 0″ W. Detected a few times by the Equatorial Pacific Ocean autonomous hydrophone array (a system using U.S. Navy technologies originally designed to monitor Soviet subs) the sound is significantly louder than a blue whale, the loudest animal on earth. As NOAA put it, the sound "rises rapidly in frequency over about one minute and was of sufficient amplitude to be heard on multiple sensors, at a range of over 5,000 km."

Dr. Christopher Fox with NOAA first postulated that ice calving in Antarctica was Bloop's source. Later, Fox would suggest it could've been some seabeast's doing. We may never know.

The autonomous hydrophone array picked up this lass in early March 1999 at 15° 0′ 0″ S, 98° 0′ 0″ W. The speed here is real-time, so to speak, having only lasted about 15 seconds.

Slow Down decreases in frequency over a span of about seven minutes. As such, it's the longest of the Drone Zone's tones. Recorded May 19, 1997, at 15° 0′ 0″ S, 115° 0′ 0″ W, Slow Down, much like Bloop, may've been the result of ice on the move, as sound spectrograms (the still images on these videos) of friction are not dissimilar to those of the frictional phenomenon of ice creeping over land.

But again, the world may never know. For now, I'll blame a Kraken.

This guy is particularly strange. It's as if the noise, a lengthy series of narrow-banded upsweeps that last for a few seconds, has been on some seasonal tip since first being detected in August 1991 near 54° S 140° W. Upsweep typically peaks in the fall and spring (whether this is a result of shifts in the propagation environment or in the source itself is undetermined – again, I'll stick to the Kraken), though its overall levels have been waning since SOSUS first picked it up.

If the ocean's aren't weird, full of creepy shit and loud enough as they are – I'll admit that today's column is long overdue – the South Pacific Drone Zone speaks to the most profound and perennial oddity: this planet. In many ways, we know more about distant heavenly bodies than everything screaming beneath our feet.

ODDITY examines strange and esoteric phenomena and events from the remote, uncanny corners of technology, science and history.

Reach this writer at brian@motherboard.tv. @TheBAnderson