Tsunami, a powerful word which can evoke fear and chaos when heard. The sheer enormity and strength of the Tsunami is known to everyone. Destroying everything in its wake, causing billions of dollars worth of property damage, killing thousands of people, and having profound environmental effects is its proficiency. Just take a look at the aftermath of the tsunamis which struck the Indian Ocean in 2004 and Japan in 2011. The countries which were affected required a huge amount of funds to recover from the impact of it. Life was disrupted for a long time and it took a while for everything to get back to normal. We know how powerful the ocean can be and when a tsunami is coming, there isn’t much we can do other than to run away in fear. What if scientists have found a way to fight tsunamis, at least theoretically? What if there is a way to lessen the power of a tsunami before it hits the land? That would be a huge lifesaver. Usama Kadri, a mathematician in Cardiff University found a theoretical way to reduce the impact of tsunamis and published it in Heliyon (Journal).
Before and after a tsunami
What did he publish?
According to Usama Kadri, a lecturer in Cardiff University said if you fire Acoustic-Gravity Waves at a tsunami could scale down its energy and size remarkably while it's still far away in the sea. As unbelievable as it may sound, you can take a look at his work here for proof- http://www.heliyon.com/article/e00234#fg0010
Acoustic gravity waves
You might be wondering what exactly an Acoustic-Gravity Wave is and what does it have to do with a tsunami. Well, an Acoustic-Gravity Wave is a special type of sound wave which can cut through the unfathomable ocean at the speed of sound. They are generated by explosions, landslides, meteorites, surface waves, and underwater earthquakes. These waves can stretch for tens to hundreds of kilometers and travel at depths of hundreds to thousands of meters below the ocean. A tsunami is preceded by these waves.
What can you do with these waves?
The next question that should be in your mind once you understand what these waves are is, what you can do with them and this is a very interesting topic. Scientists have been studying tsunamis and progress is widely reported in connection and causes, forecasting, and recovery. There is one study which deals with suppressing the effect of tsunamis using submarine barriers. Nonetheless, there is no other study which agrees with the direct way of mitigating tsunamis. Acoustic-Gravity Waves (AGW) carry extensive amounts of water, salts, carbon, and other nutrients around the world in a couple of hours. Deep water transport is crucial to the global ecosystem and any hindrance will result in drastic environmental effects. Usama Kadri in 2015 said that studying these waves could improve detecting of tsunamis earlier than usual, help sustain a healthier ecosystem, help seaside communities, and offshore facilities which are susceptible to these killer waves. This translates into precious minutes or hours, depending on the location of the source which will undoubtedly save more lives. To put things into perspective, the tsunami which hit Indonesia and Sri Lanka in 2004 would have been detected 3 and 60 minutes earlier, respectively if we used an Acoustic-Gravity Wave (AGW) alarm system if it was placed 1000 kilometers away from the epicenter of the earthquake. That is a significant improvement as it could have detected the Acoustic-Gravity Waves (AGW) within 11 minutes.
Kadri earlier this year published that theoretically, you could mitigate tsunamis using these waves. However unlikely it may seem, his work shows us that it is possible. He said that a single burst of this wave can shorten the height of the wave and spread its power over a large area. Sending out multiple waves in succession can effectively deplete the wave of its power and stop it completely. So how can this be achieved? By building an underwater cannon (sort of) or modulator which can generate these waves. These machines are supposed to send out waves which can combat a tsunami and stop it in its tracks.
Is there any difficulty in implementing it?
Nothing can sound this good, right? Well, there is a catch to this theory. The problem is that tsunamis have a lot of energy and you need a lot of these waves to effectively combat tsunamis. To produce these waves, in reality, requires a lot more energy, more than what they possess. Also, the length of workings involved to be proportionate to the length of Acoustic-Gravity Waves is illogically long, making it impractical. A workaround has been proposed which is using the naturally generated Acoustic-Gravity Waves produced by the earthquake and modifying it to match the Tsunami. Whether this is practical or not remains to be seen.
It is a big deal that we are making progress in alarm systems which can detect tsunamis faster. The fact that we are able to even consider fighting a tsunami head on shows how much our technology has advanced as they are one of the most deadly forces of nature. Detection systems are straightforward and feasible whereas mitigation of tsunamis requires designs of highly accurate systems to produce these waves, which is challenging and an on-going engineering problem. It wouldn’t be surprising if a group of scientists announces a few of years from now that we can stop tsunamis and earthquakes completely.