A US Air Force base in Texas has taken the first steps to guard against an Electromagnetic Pulse (EMP) attack. But what exactly is an EMP and how big is the threat?
Officials at Joint Base San Antonioin Lackland, Texas, issued a request for bids to carry-out a survey of a facility, called the Petroleum, Oil & Lubrication Complex.
The survey will identify any equipment which could be vulnerable to an EMP ahead more detailed vulnerability testing, consistent with the request. Then, officials would find out the ways to keep that equipment safe in the event of an EMP attack.
What is an EMP?
An EMP is a massive-burst of electromagnetic energy which can occur naturally, or be generated deliberately using nuclear weapons.
While many experts do not think EMPs pose a big threat, some people argue that these kinds of weapons could be used to cause widespread disruption to electricity dependent societies.
“You can use a single weapon to-collapse the entire North American power grid,” said defense analyst, Peter Pry, who served on Congressional EMP Commission, which was set-up to assess the threat of EMP attacks but shut-down in 2017.
“Once the electric grid goes-down, everything would collapse,” Pry said. “Everything depends on electricity: telecommunications, transportation, even water.”
According to the request, testing at Lackland comes in response to a 2019 executive order issued-by former President Donald Trump for the federal government to strengthen its infrastructure against EMPs.
Pry, who has consulted on the project said, the survey & resulting upgrades are part of a broader initiative by the U.S. Air Force to beef-up its defenses against this type of threat.
Why EMPs are so dangerous?
An EMP releases huge waves of electromagnetic energy, that can act like a giant moving magnet.
Such a changing magnetic field can cause electrons in a nearby-wire to move, there-by inducing a current. With such a big burst of energy, an EMP can cause damaging power surges in any electronics within-range.
These pulses can occur deliberately, or naturally. Natural EMP occur, when the sun occasionally spits out massive streams of plasma and if they come our way, Earth’s natural magnetic-field can deflect them.
But when the sun spits-out enough plasma at once, impact can cause the magnetic field to wobble and generate a strong & powerful EMP.
Last time, this happened was in 1859 in the so-called Carrington Event and while electronics were still rare then, it knocked-out much of the recently built telegraph network.
Then, there is the possibility of deliberate EMPs. If a nuclear weapon were to be detonated high in the atmosphere, Pry said, the gamma radiation, it would release could strip electrons from air molecules and accelerate-them at close to the speed of light.
These charge carrying electrons would be corralled-by Earth’s magnetic field and as they zipped around, they would generate a powerful, fluctuating current, which in turn, would generate a large EMP. The explosion could also distort Earth’s magnetic field, causing a slower pulse almost like a naturally occurring EMP.
Setting-off a nuclear weapon around 200 miles (300 kilometers) above the US, could create an EMP that would cover most of North America, Pry said.
The explosion & radiation from the bomb would dissipate before reaching ground level, but the resulting EMP would-be powerful-enough to destroy electronics across the region, Pry said.
“If you were standing on the ground directly beneath the detonation, you would not even hear it go-off,” Pry said. “The EMP would pass harmlessly through your-body.”
A small EMP with a radius of under a kilometer also can be generated-by combining high-voltage power sources with antennas which release this energy as electromagnetic waves.
The US military has a prototype cruise missile carrying an EMP generator, called the Counter-Electronics High Power Microwave Advanced Missile Project (CHAMP), it can-be used to target specific enemy facilities and Pry said, it would be within the capabilities of many militaries or even terrorist groups, to build an EMP generator.
“We have arrived at a place, where a single individual can topple the technological pillars of civilization for a major metropolitan area all-by himself armed with some device like this,” he said.
The technology required to guard against EMPs is similar to what’s already used to prevent damage from power surges caused-by lightning, Pry said.
These technologies would have to be adapted-to deal with higher voltages, but devices like surge protectors, which divert excess voltage into the earth or Faraday cages, which shield devices from electromagnetic radiation, could do the job.
Pry said, the EMP Commission estimated it would cost $2 billion to $4 billion to guard the most important pieces of equipment in the national grid, but ideally, he would like to see standards changed in order that EMP protection is made into devices.
EMP: Should you worry?
The threat posed-by EMPs is far from settled, though.
A 2019 report-by the Electric Power Research Institute, which is funded-by utility companies, found that such an attack would probably cause regional blackouts but not a nationwide grid failure which recovery times would be almost like those of other large-scale outages.
Frank Cilluffo, director of the Auburn University’s McCrary Institute for Cyber & Critical Infrastructure Security, said that, while an EMP attack would definitely be devastating, it is unlikely that the United States enemies would carry-out such a brazen assault.
“There are other ways that adversaries can achieve some-of the same outcomes, some-of which would be cheaper and some of which would-be less discernible,” Cilluffo said.
Such alternatives might include cyberattacks to take-out critical infrastructure, including the electric grid or even efforts to disrupt space-based communications or the GPS system that modern society is so-reliant on.
Work to guard against EMPs makes sense, particularly given the possibility of another Carrington like event, but these upgrades should not distract from efforts to shore-up defenses against more probable-lines of attack, Cilluffo said.
