Scientists propose using sound to stop killer tsunamis at sea

Most people know that if you want to cancel a wave out - whether it's a sound wave, or even a wave in the bath, then you need to blast it with an equal, and opposite wave. Next time you're in the bath have a go and you'll see what I mean.

Now, according to new research published last week in the journal Heliyon a team of international scientists, led by Usama Kadri, a mathematician at Cardiff University in the UK, have announced that they believe they've found a way to neutralise, and stop, even the most monstrous tsunamis at sea before they get anywhere near a coastline and have the opportunity to wreak untold havoc. And the principle behind it isn't too far removed from the one above, with the only difference being, rather than using your hand to create the opposing new wave, they want to use immensely powerful deep ocean sound waves called Acoustic Gravity Waves (AGW) which, if they can be harnessed or made, could stop almost an tsunami of any size as they appear.

AGWs are sound waves that occur naturally, moving through the deep ocean at the speed of sound and they can travel thousands of meters below the water surface and scientists have been studying them for years now as a means to try to predict both tsunamis and earthquakes.

The sound waves can measure tens and even hundreds of miles in length and it's believed that certain life forms, such as plankton, which are incapable of swimming against the current, rely on the waves to help them move, thus being able to find food and sustain life.

The research, which on the one hand is aims to stir debate, and on the other present a serious solution to a "problem" that's killed hundreds of thousands of people over the years, suggests that the scientific community should coordinate its thinking to find a way to engineer these massively powerful sound waves so that in a case of a tsunami, we could fire them and reduce their amplitude, height or both.

Cancelling out waves using waves

If science could find a way to engineer AGW's, and it's certainly possible, then all the evidence suggest that they'd cause the tsunami to spread its energy, dissipating it over a larger area, producing less overall harm and saving lives. Furthermore, the researcher suggests that this technique could be performed repeatedly until the tsunami is completely dissipated, lacking the power to produce damage on the shoreline.

Example AGW set up

In 2004 a tsunami in the Indian Ocean, which was triggered by a magnitude 9 earthquake, killed over 230,000 people in 14 countries and the mechanics of that tsunami's power, the energy released on the Earth's surface by both the earthquake and the tsunami was approximated to 1,500 times more powerful than the Hiroshima atomic bomb.

"Unlike surface ocean waves, AGWs form with tsunamis and induce pressure disturbances not only near the surface but in the whole water column, reaching the sea-floor where they leave measurable pressure signatures, which makes them perfect tsunami precursors. Such a detection station should be installed in the deep ocean where AGWs are expected to travel freely in the water column. This has clear benefits relative to standard warning systems that rely on the actual arrival of the tsunami," said Kadri.

For the technology to be created, engineers would need to be able to create very accurate AGW frequency transmitters or modulators, but for now in case of a tsunami, the best means of prevention currently available is evacuating people in the red flagged areas as soon as possible, immediately following the warning.

"When the instruments detect a major earthquake and the potential for a tsunami to occur, warnings are issued to local authorities who can order the evacuation of low-lying areas, if necessary," say the US National Weather Service.

However, who knows, even though Kadri's proposal like science fiction - being able to create a AGW device that can create waves with enough power to cancel out a tsunami - in an age when we're creating laser tractor beams, new alien life forms, 3D printing body parts on the battlefield and self-evolving, self-fabricating intelligent machines, never say never, and with powerful truck sized nuclear fusion reactors just over the horizon... well, maybe there's your energy source.