Russian ‘Ghost Ships’ Are Turning the Seabed Into a Future Battlefield

Baltic and North Sea nations are getting nervous about Russia’s unabashed surveys of infrastructure-laden seafloors.

A sailor stands on the deck of the Russian ship Admiral Vladimirsky during an expedition to Antarctica.
A sailor stands on the deck of the Russian ship Admiral Vladimirsky during an expedition to Antarctica.
A sailor stands on the deck of the Russian ship Admiral Vladimirsky during an expedition to Antarctica in December 2019. Alexey Kudenko/Sputnik via AP

The seabed around Denmark holds data cables that connect Europe with the world, gas pipelines that until their sabotage powered German industry, and power cables that promise to light up Europe through the world’s soon-to-be “largest power plant.” And Russia is mapping it all so it can cause havoc, stopping short of war if need be but ready to sow destruction in the event of actual conflict, experts warn.

The seabed around Denmark holds data cables that connect Europe with the world, gas pipelines that until their sabotage powered German industry, and power cables that promise to light up Europe through the world’s soon-to-be “largest power plant.” And Russia is mapping it all so it can cause havoc, stopping short of war if need be but ready to sow destruction in the event of actual conflict, experts warn.

The latest alarm came after a Scandinavian documentary series revealed how dozens of Russian vessels are being used for nefarious purposes in waters around Northern Europe. The series focuses on the Admiral Vladimirsky, a Russian research vessel that was caught traveling through Danish territorial waters last November with its positional transmitter turned off, turning it into what is known as a “ghost ship”—the same tactic that states such as North Korea use to hide illicit trading. Reporters who got too close to the so-called research vessel were greeted with masked gunmen on deck brandishing automatic weapons.

Multiple experts agree that this ship was engaging in a different illicit activity, as it was likely mapping out critical infrastructure ripe for sabotage—for example, the data cables in Danish waters that connect it and Europe to the United States and the United Kingdom; some of those very cables were the ones the U.S. National Security Agency tapped to listen in on then-German Chancellor Angela Merkel.

“The Russians have always done this, used regular ships to listen, photograph, and map areas of interest. This is clearly them laying the puzzle of our vulnerabilities,” said Nils Wang, a retired rear admiral of the Royal Danish Navy and the managing director of the export organization Naval Team Denmark. “Russia has the ability to engage in violence and pinprick operations, making our lives miserable, without going to war. It’s good we haven’t found a smoking gun pointing to Russia for [the sabotage of] Nord Stream,” Wang added, referring to the still-unexplained sabotage of two massive natural gas pipes just off the Danish coast last September.

The documentary series—titled Skyggekrigen, or “The Shadow War”—also alleges that the Admiral Vladimirsky and other Russian vessels spent time, with their transponders off, snooping around waters off the Netherlands and the U.K., including in areas near current and future wind farms. Danish waters are not as heavily loaded as the connection between the Netherlands and the U.K., but the Danish cables are important for European connection, a source in the sea cable industry said—certainly important enough to be of serious Russian interest.

“Denmark is a front-line state in the hybrid war,” said André Ken Jakobsson, a specialist in hybrid warfare at the University of Southern Denmark’s Center for War Studies.

The idea is, in short, that Russia would be able to cause power or communications breakdowns by strategically cutting cables; something just like that happened to a seabed research cable off northern Norway, and no one knows who did it. In times of actual conflict, experts fear, Russia would know exactly where to strike to blackout crucial parts of Europe.

Most modern cables are secured against accidental sabotage by being buried in the sand. Yet accidents still happen; in rough seas, a large ship could lose its anchor and then unknowingly plow through buried cables. For sabotage, all it takes is a heavy anchor, the will to drag it, and the knowledge of just where to do so.

“I think we will start seeing fishing trawlers ‘accidentally’ hitting cables. I mean, just data cables alone, they could disrupt the data flow to Europe,” Jakobsson said.

Cable-cutting has been a tactic of war since the onset of World War I, pioneered by the U.K. Royal Navy when it cut off almost all of Germany’s communications with the outside world by dredging hooks across the seabed. That forced Germany to communicate through neutral countries, but even then it couldn’t escape the British stranglehold on undersea communications: The British intercepted the so-called Zimmermann Telegram, which helped draw the United States into the war, because the inflammatory coded message went through a British cable snaking out of Sweden.

And there’s a lot more than just European telecommunications wiring on the Danish seafloor. Several European nations are currently preparing one of the biggest energy infrastructure projects in the world: building artificial energy islands that will be a central point for the distribution of up to 300 gigawatts of wind power to most of Europe by 2050. Worryingly, one of Denmark’s energy islands will be located near the island of Bornholm, right by where the Nord Stream pipelines suffered a double sabotage.

“Something we took for granted years back, that we could build in the sea and just put down electric [cables] and all would be fine, this is now a security threat,” Danish Foreign Minister Lars Loekke Rasmussen told Danish media after the revelation.

Many maritime and security experts say Rasmussen and others had downplayed the evident dangers of layering the seafloor with infrastructure owned by, in some cases, an often-hostile power.

“We didn’t even think that energy infrastructure had geopolitical importance. I mean, with Nord Stream 1, we invited Gazprom to build in our territorial waters, and … Rasmussen [at the time] thought that was a wonderful idea,” said Trine Villumsen Berling, a senior researcher focusing on the Baltic Sea at the Danish Institute for International Studies. “We had a belief that we had won the Cold War and the political system saw energy infrastructure as an engineering problem. We forgot that energy and natural resources are always something to be counted when measuring power.”

The Danish Justice Ministry is currently exploring the possibility of declaring the areas around offshore windmills and other critical infrastructure as “security zones,” making sailing there illegal and allowing the Danish navy to escort any ship—fishing, research, or other—out of the area. And neighboring Sweden expelled five Russian diplomats at the end of April for carrying out activities that were incompatible with their diplomatic status.

“Denmark has woken from its Sleeping Beauty slumber where war was something far away under foreign skies. Now we need to talk about defending our critical infrastructure,” said Lars Bangert Struwe, the general secretary of the Atlantic Alliance, a think tank in Copenhagen.

The reason extensive surveying, like what Russia is apparently carrying out, is problematic is that it can offer a potential ill-doer the whole blueprint of undersea power and data cables. The grid is not vulnerable to a single point of failure—as could happen with an accidental trawling incident—but would buckle under a coordinated attack, said a representative of the Danish energy services. “No system can handle all power lines or international connections getting cut at once. It’s like pulling the plug on all production essentially,” the representative said on condition of anonymity as they were not authorized to speak to the media.

The fear of Northern Europe’s seabed being mapped out is best exemplified by the North Stream pipelines episode last September. Though no group or state has been conclusively linked to the damage to both pipelines, which effectively put them both out of commission, both Danish and Swedish authorities say there were clear signs of sabotage. In order to carry out such a sophisticated attack on a pair of pipelines almost a day apart, one needs to know exactly how things look down in those murky depths. And Russian ships seem to be doing much of the looking, even if only on the sly.

“Russia is constantly moving close to the threshold of war. They can threaten to essentially cut off Northern European communication or energy,” Struwe said.

Morten Soendergaard Larsen is a freelance journalist based in Seoul who writes about geopolitics.

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