Scientists have known for decades that an extreme solar storm, or coronal mass ejection, can damage electrical networks and possibly cause prolonged blackouts. The impacts would be felt everywhere from global supply chains and transportation to the internet and GPS access. Until now, however, less research has been done on the impact such solar emission could have on internet infrastructure specifically. New research shows the outages could be catastrophic, particularly for the undersea cables that power the global internet.
At the SIGCOMM 2021 data communications conference on Thursday, Sangeetha Abdu Jyothi of the University of California, Irvine presented “Solar Superstorms: Planning for an Internet Apocalypse,” a study examining the damage a fast-moving cloud of magnetized solar particles could cause to the global Internet. Abdu Jyothis Research points out an additional nuance to a solar storm that causes blackout: the scenario where even if power returns within hours or days, massive internet outages persist.
There is good news beforehand. Abdu Jyothi found that local and regional internet infrastructure would have a low risk of damage even in a massive solar storm, because fiber itself is not affected by geomagnetic currents. Short cable spans are also grounded very regularly. But for long submarine cables connecting continents, the risks are much greater. A solar storm that disrupted some of these cables around the world could cause a massive loss of connectivity by shutting down countries at the source, even if local infrastructure remains intact. It would be like cutting off power to an apartment building because of a water pipe burst.
“What really got me thinking is that with the pandemic, we saw how unprepared the world was. There was no protocol to deal with it effectively and so was the resilience of the internet,” Abdu Jyothi told WIRED ahead of her talk. “Our infrastructure is not prepared for a large-scale solar event. We have very limited insight into the extent of the damage.”
This information gap is usually due to a lack of data. Severe solar storms are so rare that in recent history there are only three significant examples to rely on. Major events in 1859 and 1921 showed that geomagnetic disturbances can disrupt electrical infrastructure and communication lines such as telegraph wires. During the massive “Carrington Event” in 1859, compass needles swung wildly and unpredictably, and the aurora borealis was visible at the equator in Colombia. But those geomagnetic disturbances occurred before modern power grids came into existence. A moderate solar storm in 1989 knocked out Hydro-Québec’s power grid and caused a nine-hour blackout in northeastern Canada, but that too happened before the rise of modern Internet infrastructure.
Although not common, coronal mass ejections pose a real threat to internet resilience, Abdu Jyothi says. And after three decades of low solar storm activity, they and… other researchers indicate that the probability of a subsequent incident increases.
Undersea Internet cables may be susceptible to damage from solar storms for a number of reasons. To route data intact across oceans, cables are equipped with repeaters at intervals of about 50 to 150 kilometers, depending on the cable. These devices amplify the optical signal and ensure that nothing is lost during transport, such as a relay throw in baseball. While fiber optic cable isn’t directly vulnerable to disruption from geomagnetically induced currents, the electronic insides of repeaters are — and enough repeater failures will render an entire submarine cable useless. In addition, submarine cables are only grounded at longer intervals, hundreds or thousands of miles apart, leaving vulnerable components such as repeaters more exposed to geomagnetically induced currents. The composition of the seafloor also varies, so some grounding points may be more effective than others.