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Chinese merchant ships that appear to take an unusual interest in ocean floor infrastructure are not the only things causing disorder in the Baltic Sea. In recent months, automatic identification system (AIS) spoofing has been increasing there, too. Since these systems exist to allow ships to know where they and other ships are, manipulation that shows vessels being somewhere completely different is not a trivial matter. But Western governments can’t do very much about it—and other countries could adopt the subversive practice, too.
The Yi Peng 3, a Chinese bulk carrier, has emerged as the prime suspect in the Baltic Sea cable cuts in November. After the incident, the vessel made its way westward, toward the Atlantic but anchored in the Kattegat Strait between Denmark and Sweden. It has remained there, watched by Danish naval vessels (as the ship is in Denmark’s exclusive economic zone) and sometimes by Swedish and German coast guard vessels, as well.
Chinese merchant ships that appear to take an unusual interest in ocean floor infrastructure are not the only things causing disorder in the Baltic Sea. In recent months, automatic identification system (AIS) spoofing has been increasing there, too. Since these systems exist to allow ships to know where they and other ships are, manipulation that shows vessels being somewhere completely different is not a trivial matter. But Western governments can’t do very much about it—and other countries could adopt the subversive practice, too.
The Yi Peng 3, a Chinese bulk carrier, has emerged as the prime suspect in the Baltic Sea cable cuts in November. After the incident, the vessel made its way westward, toward the Atlantic but anchored in the Kattegat Strait between Denmark and Sweden. It has remained there, watched by Danish naval vessels (as the ship is in Denmark’s exclusive economic zone) and sometimes by Swedish and German coast guard vessels, as well.
But other vessels are also causing headaches for Scandinavian governments. Pekka Niittyla of the Finnish Coast Guard told Reuters that ships sailing through the Gulf of Finland in recent weeks have been turning off their AIS. Lulu Ranne, Finland’s minister of transport and communications, said Russia is likely interfering with navigation systems. That matters because the Gulf of Finland and the rest of the Baltic Sea are busy waters with narrow and congested shipping lanes.
Satellite navigation systems, which help ship crews know their location and that of other vessels, are indispensable in modern shipping and to modern economies. Last year, the United Kingdom’s government calculated that Global Navigation Satellite Systems (GNSS) provide economic benefits of $17.2 million each year. Ships, in turn, are required to use AIS, which signal their location. But now Russia is interfering with those systems—messing both with the satellites that send the signals and with the AIS signals sent from some of the ships themselves.
For ships going about their business in the Baltic Sea, that means they may see a ship very nearby that, according to their radar, is somewhere completely different. “This is something that is coming in the wake of the Ukraine war,” said Nils Wang, a retired admiral and former Danish Navy chief. “We’ve definitely seen an increase since February 2022. The Russians’ ability to engage in AIS spoofing and related disturbances has increased, which seems to be a result of what they’re doing in the Black Sea. They’re becoming very good at it.”
The Black Sea appears to have served as a laboratory for the AIS spoofing now taking place. In 2017, merchant vessels traveling in the Black Sea began reporting mysterious oddities in their locations. They knew roughly where they were, but their radars showed them being somewhere completely different, often on land. An alert issued by the U.S. Maritime Administration read, “A maritime incident has been reported in the Black Sea in the vicinity of position 44-15.7N, 037-32.9E on June 22, 2017 at 0710 GMT. This incident has not been confirmed. The nature of the incident is reported as interference. Exercise caution when transiting this area.”
Since then, AIS incidents linked to Russia have accelerated. In May 2022, C4ADS, a Washington-based nonprofit, reported that it had identified 9,883 suspected instances of such interference across 10 locations that affected 1,311 civilian vessel navigation systems since Feb. 2016. Last year, suspected Russian AIS spoofing created a “Z” pattern of vessels on radar screens. (“Z” is the Russian symbol for the war in Ukraine.)
Now, GNSS and AIS disturbance is growing in the Baltic Sea—hardly a coincidence. The majority of Russia’s shadow fleet—which transports Russian crude above the price cap imposed by Western governments in response to its invasion of Ukraine—travels to and from Russia’s ports in the Gulf of Finland (the Baltic Sea’s easternmost part). Since shadow vessels operate in, yes, the shadows, they take pains not to advertise their position. That means they turn off or spoof their AIS. If someone also interferes with the navigational systems themselves, significant disorder results.
Back in 2022, Danish officials discovered that mysterious GPS dysfunctions on the ferry between the Danish island of Bornholm (which is located southeast of Sweden) and mainland Denmark had been caused by jammers in two trucks. “Disrupting GNSS and GPS is one of the things Russians are extremely good at. It’s also in their interest to spoof AIS, and it’s no surprise that this is primarily taking place in the Gulf of Finland, since it’s the primarily the Finns seeing what goes in and out of Russia’s Baltic Sea ports,” said Anders Grenstad, a retired admiral and former Swedish Navy chief.
Spoofing of identification signals—which can also be achieved through attacks on GPS and similar systems—is also a way of creating disorder without fear of punishment or retaliation. (It is, in other words, perfect gray-zone aggression, which is a type of nonmilitary aggression sometimes referred to as hybrid warfare.)
“This is the Russians’ way of protesting against Sweden’s and Finland’s accession to NATO and the establishment of what people call a ‘NATO lake,’” Wang said. “They’re sending the message that even though NATO dominates the Baltic Sea, they can still engage in subversive actions.” Cheerful Western talk about a NATO lake suggests the Baltic Sea is far more peaceful than it actually is, and it risks triggering not just Russian AIS disturbance but lots of other subversive activities.
That disturbance could result in collisions precisely because ships’ real location is different from what’s on the radar. That means it’s only a matter of time before there’s an accident. AIS jamming makes navigation harder for all ships, but AIS spoofing, which entails creating a false picture, presents a real danger to other ships.
“The Russians circumvent the rules that govern shipping, which undermines the maritime order that we work hard to abide by … The only acceptable reason to switch or spoof is to avoid a piracy attack or other safety concerns,” Line Falkenberg Ollestad, an advisor at the Norwegian Shipowners Association, said.
Collisions would, of course, cause harm to the Baltic Sea’s already weakened maritime environment. “AIS is meant to increase maritime insecurity,” Grenstad said. “Instead, it could cause collisions. That poses enormous dangers to the environment … If ferries or cruise ships collide, it would cause loss of life.”
Fortunately, shipmasters are skilled professionals and often detect when something is iffy with other vessels’ radar locations. “The risk is that if you’re in waters with dense traffic like in the Danish [straits] and the Baltic [Sea], the master will be confused if his GPS doesn’t work or if he sees AIS tracks that he can’t see with radar or with the naked eye,” Wang said. “That means he has to slow down to find out what’s going on. That creates delays.”
Such delays will be exacerbated by the fact that today’s seafarers are used to sailing with digital tools like GPS and AIS. “If you can’t rely on your electronic means, you have to use manual tools, but not too many seafarers are used to that anymore,” Wang said. GPS or AIS disturbance thus risks causing delays, which means delayed arrival of cargo in every subsequent port. That will result in economic harm not just to the affected shipping lines but to countries, too.
What can be done about this menace? Not very much, because NATO is hardly going to use its military might to punish some electronic disturbance. And responsible countries, like the other Baltic Sea states, would never retaliate by, say, spoofing merchant traffic in the Caspian Sea. The spoofing in the Baltic Sea will continue and perhaps even grow, and it’s already being joined by other subversive activities like the severing of undersea cables.
When it comes to navigational interference, other countries should watch the Russians’ experiments in the Baltic Sea and the Black Sea. “This is beginning with Russia because they’re so good at it, but it could spread to China, and Iran, and other countries that have an interest in disguising their activities,” Grenstad said. “It’s incredibly perilous for the international maritime order.”
The NATO lake was never going to be placid.