Le Mystère du Hum Dans la Zone Crépusculaire de l'Océan

Sympa

Dans la zone crépusculaire de l'océan, les scientifiques ont découvert un étrange bourdonnement à basse fréquence - et personne ne sait exactement ce qui le cause. 🌊🐠 Ce son mystérieux pulse à travers l'eau et se produit chaque jour, juste autour du lever et du coucher du soleil. Certains experts pensent qu'il pourrait provenir de millions de minuscules créatures marines se déplaçant de haut en bas dans l'eau, comme une immense migration sous-marine. D'autres croient qu'il pourrait être lié aux courants océaniques ou même à des formes de vie marine inconnues communiquant de manière que nous ne comprenons pas encore. Quelle qu'en soit la cause, ce bourdonnement étrange est différent de tout ce que nous avons entendu auparavant ! Peut-être que résoudre ce mystère permettra de dévoiler des secrets sur les profondeurs marines que nous n'avions jamais imaginés. 🌊🔍  Animation créée par Sympa. ---------------------------------------------------------------------------------------- Musique par Epidemic Sound https://www.epidemicsound.com   Pour ne rien perdre de Sympa, abonnez-vous!: https://goo.gl/6E4Xna​ ---------------------------------------------------------------------------------------- Nos réseaux sociaux : Facebook: https://www.facebook.com/sympasympacom/ Instagram: https://www.instagram.com/sympa.officiel/  Stock de fichiers (photos, vidéos et autres): https://www.depositphotos.com https://www.shutterstock.com https://www.eastnews.ru ----------------------------------------------------------------------------------------  Si tu en veux encore plus, fais un tour ici:  http://sympa-sympa.com

Transcript

00:00Here you are, while you take a seat on board your submarine, apprehension wins you.

00:06You are about to dive several hundred meters to explore the abysses.

00:10But so many things could go wrong.

00:12Technical failure, crushing pressure, terrifying marine creatures, and strange noises.

00:17Indeed, an enigmatic rumbling emanates from the depths.

00:21Even more disturbing, it seems to manifest only at dawn and dusk.

00:26This sound could play a role similar to that of a bell announcing the time of the meal.

00:31Because it seems to be linked to the movement of large numbers of marine creatures in search of food.

00:36But this is still a hypothesis.

00:39Thanks to extremely sensitive underwater microphones,

00:43researchers have captured a low-frequency rumbling between 200 and 1000 meters deep.

00:48This sound, although perceptible, only exceeded 3 to 6 decibels, the usual background noise of the ocean.

00:55For comparison, a whisper in the calm of a library reached about 30 decibels.

01:01This acoustic phenomenon was distinguished by a tonality oscillating between rumbling and rumbling.

01:06The most intriguing?

01:08Despite their efforts, scientists have not been able to identify with certainty the species at the origin of this sound.

01:14The origin of this sound is located at a depth known as the twilight zone.

01:20This space, plunged into darkness, is poor in nutrients and devoid of essential solar light for photosynthesis.

01:27The fauna that thrives there depends on suspended organic particles and dead organisms falling from the upper layers.

01:34Despite this apparent austerity, the twilight zone is far from desert.

01:39A 2015 study suggests that up to 90% of the fish on the planet could reside there,

01:45among which many species still unknown.

01:49Let's go back to this enigmatic noise.

01:51Researchers estimate that it could be linked to the vertical migration of small marine creatures such as fish, shrimp and squid.

01:58These animals go up to the twilight surface to feed on plankton, taking advantage of the darkness to escape predators.

02:06At dawn, they dive back into the depths to hide.

02:10This phenomenon, one of the largest animal displacements on Earth, mobilizes billions of organisms every day.

02:17Scientists assume that this hustle and bustle accompanies this migration,

02:21perhaps serving as a means of communication or coordination.

02:25They could also signal to the group the right time to go back to feed.

02:29If this hypothesis is confirmed, it would make it possible to better understand life in the abyssal depths.

02:35For a long time considered as the kingdom of silence,

02:37the twilight zone could actually be home to social interactions and much more elaborate behaviors than we imagined.

02:46But the ocean is not the only one to produce strange sounds.

02:49The Earth itself emits an incessant rumbling.

02:52This phenomenon, inaudible to the human ear, has nothing to do with earthquakes.

02:57It results from tiny vibrations and continues within the earth's crust,

03:02so weak that they can only be detected with specialized equipment.

03:07Known as free oscillation, this resonance, observed for a long time by scientists, could be recorded.

03:15Earthquakes, on the other hand, are the most perceptible ground movements.

03:20According to the Institute for Geological Studies of the United States, the Earth undergoes about 5 million earthquakes each year.

03:26Among them, only 100,000 are powerful enough to be felt, and a hundred cause significant damage.

03:34Even during the calms between two earthquakes, the Earth vibrates constantly under the effect of imperceptible movements.

03:40Contrary to the brutal shaking of earthquakes, this rumbling is constant and regular, resulting in micro-seismic activity.

03:48Seismometers, instruments measuring the vibrations of the ground, are able to capture this phenomenon everywhere on Earth.

03:55For years, the origin of this rumbling has been debated among researchers.

03:59Some attributed it to waves deeply penetrating the seabed, others to the collision between surface waves.

04:06In 2015, it was confirmed that these two mechanisms contributed to the permanent vibration of the planet.

04:12If this phenomenon had already been recorded on Earth, the underwater data is now much more precise and detailed.

04:20To study it, scientists deployed seismometers at the bottom of the Indian Ocean, near an island east of Madagascar.

04:27Between September 2012 and November 2013, 57 autonomous seismometers were distributed over an area of 2,000 square kilometers.

04:36Designed to reach the ocean floor, these devices record the most subtle vibrations.

04:42During these 11 months of study, researchers filtered the interferences linked to waves and sea currents.

04:48They were able to isolate clear and constant signals of the Earth's rumbling, with peaks of frequencies between 2.9 and 4.5 millihertz,

04:57well below the threshold of human perception, set at 20 hertz.

05:01The detection of the Earth's rumbling from the abysses goes beyond the scope of simple scientific curiosity.

05:07It offers researchers a new approach to analyze the propagation of energy through crust and the Earth's mantle.

05:15The world around us is full of enigmatic sounds, some of which remain unexplained.

05:20Among them, the bloop remains one of the most fascinating.

05:24Recorded in 1997 by the American Oceanic and Atmospheric Observation Agency, NOAA,

05:30this powerful underwater sound of a minute began with a deaf rumble before seeing its frequency intensify.

05:36With an intensity such that it was captured over 4.8 million kilometers,

05:40the bloop first fueled speculations about the existence of a gigantic marine creature still unknown.

05:46However, NOAA later established that it probably came from the village of Iceberg,

05:51when huge blocks of Antarctic ice detached before collapsing into the ocean.

05:56Other marine sounds remain just as enigmatic.

06:00Julia, a strange murmur, could be linked to the rattle of an iceberg on the ocean floor.

06:06Another, named Train, evokes the rolling on a railway and seems to come from the Ross Sea in Antarctica.

06:14As for Loopsweep, a strident seasonal sound recorded in the Pacific since 1991,

06:20its exact origin remains undetermined despite years of research.

06:25The underwater world also reveals singular sounds similar to fish hearts.

06:30Off the coast of Port Headland, in Western Australia,

06:34scientists have discovered that some marine species sing in synchronization with dawn and dusk, like birds.

06:41Over a period of 18 months, researchers have recorded a multitude of sounds,

06:46including the deaf and deep calls of the cichlids, comparable to mist horns,

06:51as well as the rhythmic ba-ba-ba sequences of the platax.

06:55These songs, characterized by repetitive patterns overlapping within vast groups,

07:00play an essential role in the reproduction, feeding and territorial dynamics.

07:07The abysses also hold their share of acoustic mysteries.

07:11NOAA researchers have explored the sounds emanating from the Challenger Deep,

07:15the deepest point of the Marian Basin.

07:18Thanks to a microphone encapsulated in titanium,

07:21able to withstand a pressure exceeding 1,000 times that of the atmosphere at the surface level,

07:26they have recorded, for 23 days, a myriad of sounds,

07:30ranging from the whistling song of whales to the distant rumbling of earthquakes.

07:34If the depths of the ocean are full of enigmatic sounds, the mainland is no exception.

07:39One of the most confusing phenomena is HUM,

07:42a serious rumbling heard in specific regions,

07:45such as Taos, New Mexico, or Bristol, England.

07:50Described as a slight rumbling evoking the rumbling of an engine,

07:54this noise remains an enigma.

07:56Some researchers advance the hypothesis of a psychological phenomenon,

07:59where the attention of individuals would be focused on sounds of background usually ignored.

08:04To date, no definitive explanation has been found.

08:09Even rock formations are able to sing.

08:12The Rainbow Bridge, a 90-meter-high ridge located in Utah,

08:17vibrates like a guitar string under the effect of sound waves,

08:21distant earthquakes, or waves from Lake Powell.

08:24Scientists analyze these frequencies to assess their impact on the stability of the structure over time.

08:30Intriguing fact, some visitors claim to hear slight rumbling as they approach the site.

08:36The sky, too, reserves its own strange harmonies.

08:40For centuries, the populations of the polar regions have been hearing rumblings,

08:45whistling, and clacking accompanied by the auroras of Boreal.

08:49A Finnish researcher made the first recordings of these sounds

08:53and identified their origin, electrical discharges in the low atmosphere,

08:57about 70 meters from the ground.

09:00Powered by magnetic storms,

09:02these charges produce perceptible low sounds during clear and calm nights.

09:07Other natural phenomena generate sounds as powerful as intriguing.

09:12The rubbing of icebergs on the seabed and underwater volcanic activity

09:17generate rumblings, creaking and creaking

09:20that scientists analyze to better understand the glacial and geological dynamics.

09:25As for me, I also produce my share of strange noises,

09:29but that's a subject for another video.

09:31Or maybe for my next medical report.

Category

Transcript

Recommended