Undersea passage, are you going the right way?

  Since the beginning of this year, the seabed has not been flat.
  From Japan’s nuclear sewage discharge plan, the natural gas leak of the “Beixi” pipeline, to the nationwide disconnection of Tonga caused by a volcano… everything points to the secrets deep under the sea. But if it weren’t for the sudden news one after another, we might still be immersed in Verne’s gorgeous fantasy about the deep sea, without realizing that in the dark and dark place, the steel giants have already used blood and sweat as ink, and used another kind of The method has written a magnificent chapter.
  There is a Chinese folk saying: reality is more exciting than fiction. That’s right, this time, the theme of the chapter is not only about courage and wisdom, greed and selfishness, but also directly points to the weakness of human beings, showing the absolute power of nature. The ups and downs and fate in it, I am afraid that Verne would sigh after reading it.
Take a hard shortcut from the bottom of the sea

  Whether it is the legends of sea monsters or monsters, or the scientific conception of submarine construction, compared with landlocked countries, island countries surrounded by the sea always have more active ocean reverie. For example, Japan was one of the first countries to propose the idea of ​​an undersea tunnel.
  As early as 1923, Kakuji Abe proposed for the first time the idea of ​​running through the Tsugaru Strait from the bottom of the sea in “The Great Hakodate Theory”. After all, 2/3 of the earth is ocean. If you want to take a shortcut and go from the sea bottom, it is The most intuitive possibility. But this idea spread with World War II, and it was just an understatement on paper for more than 20 years.
  Because, although the walruses in the Tsugaru Strait are bad, the communication between Honshu and Hokkaido has been mainly through 4-5 hours of shipping for a long time. Even if typhoons interrupt shipping at least 80 times a year, people have become accustomed to patience. If there is no reason for “have to”, it is human nature to seek benefits and fear difficulties.
  Until 1954, a shipwreck of unprecedented scale gave the Japanese people this reason. On September 26, the “Toya Maru” ferry carrying 1,337 people crossed the Tsugaru Strait despite the harsh walrus conditions. On the way, it encountered violent waves and capsized. Only 182 people were rescued and survived, and the rest were all drowned or missing; those who died in the same storm , and four other ships, with a total death toll of more than 1,400, making it one of the worst maritime disasters in post-World War II and Japanese history.
  From this moment, the Japanese people and government, driven by anger and grief, are determined to dig the longest and most difficult undersea tunnel in history (total length 53.85 kilometers, 23.3 kilometers under the sea). Construction of the Seikan Tunnel started in 1961. It took 27 years and cost 2.7 billion US dollars to penetrate. During the process, the tunnel was submerged twice by sea water, 33 workers were killed and 1,300 people were disabled. But after it is completed and opened to traffic, the tunnel will shorten the travel time from the main island of Japan to Hokkaido to 30 minutes, and will no longer be affected by walruses, allowing it to pass all year round.

A Russian construction worker during a ceremony marking the start of construction on the Nord Stream pipeline, April 9, 2010.

  Some people ridiculed this belated project as one of the three stupid things of the Showa era in Japan.

  It is a pity that time waits for no one. In the past 30 years since the construction of the Seikan Tunnel, the global sea, land and air transportation has developed rapidly. When the tunnel was finally opened to traffic in the 1980s, the initial demand for “transportation” was no longer so urgent. In addition, the cost of subsea tunnels was high, and going from the bottom of the sea was no longer the best solution for “cutting corners”. Some people ridiculed this belated project as one of the three stupid things of the Showa era in Japan. However, it is undeniable that under the technical conditions at that time, many unprecedented problems solved in the construction of the Seikan Tunnel still provided an important reference for the subsequent human submarine construction.
  And if we refer to the news that Japan decided to dig an undersea tunnel to discharge nuclear sewage this year, we will be even more embarrassed. Today, as the subsea tunnel excavation technology is becoming more and more mature, the Japanese government has instead chosen the most convenient, short-sighted, and irresponsible way to solve the problem, no longer the wisdom and courage of the past.
Online all the time, offline anytime, anywhere

  Although today it seems that the transportation necessity of the Seikan Tunnel is no longer what it used to be, fortunately, by taking advantage of the opportunity of excavation, a large number of cables and optical fibers were buried in the tunnel at the same time. In fact, if people can see through the seabed, they will find that the aorta of transoceanic communication between islands and continents in the world today is not tunnels, but submarine electrical (optical) cables. There are currently about 428 submarine cables/optical cables in the world, with a total length of 683,508 miles (about 1.1 million kilometers), providing Internet and communication connections for the world, and undertaking 95% of information transmission in human society.
  In the 19th century, the emergence of gutta-percha allowed metals to be wrapped in it without seawater corrosion, making it possible to lay cables/optical cables on the seabed; but it also went through arduous attempts from theory to practice.

On March 13, 1988, on the platform of Hakodate Station, Hokkaido, Japan, the train passed through the Seikan Tunnel for the first time

An oil painting based on the shipwreck of the “Toya Maru” ferry on September 26, 1954

  When humans first laid submarine cables in the English Channel, some fishermen mistakenly thought they had found a big fish and pulled the cables out of the seabed. So the engineers knew that the submarine cable must be strong, because it must resist the bite of sharks; at the same time, it must be soft, otherwise it will be difficult to lay accurately; of course, the process must be precise, because maintenance is not so easy.
  So, although what the submarine cable/optical cable really does is probably just a thin bundle of optical fibers at the core, it is wrapped in layers of polyethylene, polyester resin or bitumen, steel strands, aluminum waterproofing, Layers of polycarbonate, copper or aluminum tubes, layers of paraffin, alkane… the diameter is as thick as an arm, and the weight per meter is as high as 10 kg. When laying, it is necessary to first wash out a ditch with the seabed sediment, bury the cable/optical cable, and then cover the sediment with burial. With more than a century of experience accumulated by human beings, the service life of submarine electric (optical) cables has reached 25 years.

  But the premise is that there will be no disasters in the past 25 years. Otherwise, for example, in February this year, the underwater volcano Hunga Tonga in the South Pacific island country of Tonga violently erupted and caused a tsunami, which caused the interruption of Tonga’s national flights and shipping. More than 100,000 people on multiple islands have lost contact with the outside world, and the entire country seems to have disappeared from the earth.
  On the vast ocean, Tonga is not the only island that keeps in touch with the outside world only by a submarine cable. Most of the island countries on the earthquake belt are not unfamiliar with this situation. After earthquakes, volcanoes, and tsunamis, some websites may not be able to log in, or they may be completely disconnected, depending on the degree of damage to the electrical (optical) cables.
  After Tonga’s undersea cable snapped, people waited for volcanic activity to stop, and it took four weeks to restore communication, which was costly. People know this isn’t the first and won’t be the last. Admit it, the ocean is an absolute force that man has so far been unable to conquer. But just like human beings more than a century ago, with great enthusiasm, they tried four times to cross the ocean with a cable as thin as a gossamer, so that the voice of the other half of the earth is close to their ears. People will not give up the submarine cable because of this. / optical cable, and will not give up the possibility of connection.

submarine cable

Russian drilling platform in the sea
It is easy to cut through the waves, but it is too difficult to defend teammates

  Whether it is a submarine tunnel or a submarine cable, it is dangerous to go through the complexity and treachery of nature; it is difficult to survive in the rapids and dangerous rivers of the seabed.
  During the construction of the Seikan Tunnel, seawater leaked, and the engineers poured a layer of cement slurry as thick as 4.5 meters around the entire tunnel, and blocked the rock cracks with steel plates. In the laying of submarine optical cables, the seawater is highly corrosive, and whale sharks come and go, so engineers wrap the optical fiber bundles layer by layer. Humans have invented thermal sensing points, fire detectors, automatic sprinkler devices, early earthquake detection systems, water leak detectors, etc. to ensure underwater safety, and tried to lay more submarine cables/optical cables to deal with natural disasters. In short, human beings seem to have forged a sharp knife with resilience, courage and wisdom, and cut through the waves to open a path.
  But it turns out that cutting through the waves is not the hardest part. Healers don’t heal themselves, gods can’t count their own lives, and the real collapse often happens from within human beings. On September 27 this year, the Danish Energy Agency first discovered a natural gas leak in the nearby sea. The bubbles at the leak rose to the sea surface, forming a bubble group with a diameter of more than 1 kilometer. Later, all parties confirmed that several points of the “North Stream” pipeline, the energy artery that transports natural gas from Russia to Europe, were damaged by man-made explosions on the same day.

  With more than a century of experience accumulated by human beings, the service life of submarine electric (optical) cables has reached 25 years.

  Speaking of which, when “Beixi No. 1” was put into construction under the promotion of Russia and EU countries in 2006, it was also known as an offshore super project. On the one hand, it is because of the long laying of pipelines, but on the other hand, the real difficulty lies in the fact that this project starts from the Russian port of Vyborg in the east, crosses the Gulf of Finland and the Baltic Sea to Greifswald in Germany, involving the United States, Ukraine, the Baltic Sea The interests of the three coastal countries, Russia and other countries are complicated in geopolitics.
  Who would have thought that the construction of the “Beixi No. 1” project was completed in 2011, but it has since become a thorn in the eyes of many countries. This is especially true for “Beixi No. 2”, which will be completed in 2021. Today, there are two “useless” pipelines lying on the seabed, and Russia at sea is holding torches to burn excess natural gas. At the moment when countries are pushing back and suspecting, scientists estimate that the natural gas leaked this time reached 778 million cubic meters, equivalent to the release of 500,000 tons of methane. The greenhouse gas effect of methane is 25 times that of carbon dioxide, and it is more difficult to remove when released into the atmosphere than carbon dioxide.
  While people calculate that the surge in natural gas prices will bring heavy pressure to the European economy, almost no one cares about how the pollution will affect marine life. A super project that once stirred up the Baltic Sea and even the Atlantic Ocean has almost withdrawn from the stage of history in the mist, and has become a secret buried deep in the seabed.