Dimitris Drikakis, a fluid dynamics researcher at the University of Nicosia in Cyprus, led the study both to illuminate the ongoing risks of nuclear escalation and to examine how one might stand a chance of survival if the unthinkable were to happen. “People have forgotten the devastating impacts nuclear war can have. But now we’re seeing the discussion start again, and there’s a debate about the potential for nuclear war in Ukraine,” Drikakis says. “I think this type of study raises awareness within the wider population that nuclear explosions are no joke.”
His sombre research comes just as the Bulletin of the Atomic Scientists announced it has ticked the mark Doomsday clock forward, 90 seconds to an apocalyptic midnight, citing the rising nuclear tensions that followed Russia‘s invasion of Ukraine. Scientists and artists have developed the metaphorical clock to communicate the risks posed by man-made global problems including climate changebut the dangers of nuclear war they have been a major focus since its inception.
Drikakis sifted through scientific research on what the consequences of using nuclear weapons would look like and identified a gap: There is little knowledge of the effects on humans indoors in the “moderate damage zone” a few miles from the epicenter. far enough that the buildings might not be torn apart. He and his colleague Ioannis Kokkinakis focused on this area and published their work in Physics of fluids diary last week.
Since nobody goes around testing nuclear weapons on buildings these days, this type of research uses computer simulations. Drikakis and Kokkinakis simulated the effects of the explosion of a 750-kiloton warhead – such as the hundreds of largest bombs in Russia’s arsenal – launched by an ICBM, which would explode about 3 kilometers above a metropolis. They studied how supersonic shock waves would propagate through a three-room concrete structure located in the moderate damage zone and hypothesized that the concrete was strong enough to withstand the pressure of 3 to 5 pounds per square inch of the wave shock.
Their research shows that, if an atomic bomb were ever detonated in a modern city, some people in the surrounding areas would have made it. They may have five to 10 seconds after the initial flash to get to safety. If they were in a thick concrete structure with few openings, like in a bank or subway, they might survive if they used that limited time to run into the corner of a back room with few openings.
Being in an enclosed space is important because, the researchers find, the winds that follow the initial fireball can be even more dangerous and deadly than the explosion itself. These winds push outward behind the shock wave, and anyone bearing the brunt of it could be slammed into a wall at high speed. Winds are especially dangerous if a person is near a door or window or in a hallway or opening in a room. Winds quickly funnel through such areas, tossing people and furniture around – it’s like a storm raging through a building.
(If you are wondering if you can copy the Indiana Jones to move The realm of the crystal skull, survive a nuclear explosion by jumping into a refrigerator, says Drikakis could To be possible. But it’s also possible that the strong wind will blow the refrigerator with Indy inside.)
Ferenc Dalnoki-Veress, scientist in residence and nuclear physicist at the Middlebury Institute of International Studies in Monterey, points out that if more buildings are between the structure you’re standing in and the incoming blast wave, that shadow effect can diminish. the speed and the forces involved. Those in a basement could avoid even the worst effects of the explosion. “A lot of people have a nihilistic view that there’s nothing we can do about it,” but that’s not the case, he says.
But let’s be honest: most people, even in the moderate damage zone, won’t survive. Hardly anyone lives or works in almost windowless reinforced concrete buildings, nor in the vicinity of a concrete bunker. (Even people in a bank would have to go into the vault to be in the safest place; people in a subway would benefit the most in a station that is very deep underground.) Most people live in wooden structures or in other less armored buildings.
This shouldn’t be interpreted as a way to be safe in a nuclear explosion, says Dylan Spaulding, an earth scientist and nuclear expert at the Union of Concerned Scientists. Strong structures made of concrete with metal reinforcement and designed for seismic safety would survive the pressures the team modeled, he says, but those pressures would be enough to destroy most traditional wood-frame homes and unreinforced brick structures.
And he points out that the shock wave is only part of the story. While it is the main source of danger in a non-nuclear explosion, such as the one that rocked Beirut in 2020caused by a large amount of flammable ammonium nitrate stored in the city’s port. Nuclear weapons also emit ionizing radiation and heat, followed by radioactive fallout.
Radiation exposure through the skin or inhalation can have many health effectsincluding skin burns, organ damage, and cancer. The radiation exposure radius could extend tens of miles from the epicenter, so people who survive the blast could later be knocked down by radiation.
Drikakis’ example focused on what is termed a “strategic” atomic bomb deployed on an ICBM, but there are also “tactical” nuclear weapons, which are dropped from an aircraft onto a battlefield and which can explode on the ground. Such explosions play out differently but can be just as lethal and destructive, potentially exposing more people to lethal doses of radiation, Spaulding says.
Russia and the United States also possess so-called low-yield nuclear weapons, which have 5 to 10 kilotons of yield and are somewhat smaller than the 15 kiloton bomb dropped on Hiroshima. These would still inflict massive devastation and cross a dangerous red line, perhaps escalating a conflict to the use of larger weapons.
Mankind’s most destructive weapons have only been used in warfare once, when the United States demolished Hiroshima and Nagasaki, Japan, with two atomic bombs at the end of World War II in 1945. Together they killed more than 100,000 Japanese civilians and they injured many more. And Spaulding points out that together with the experiments conducted at Nevada Test sitethey offer some of the only real-world evidence on the types of structures that can survive an atomic blast, and how well.
But last year Russian President Vladimir Putin hinted as much nuclear weapons are not off the table in his attack on Ukraine. While NATO leaders have not used such threatening rhetoric, the international organization conducted nuclear exercises in October, simulating the launch of B61 nuclear bombs. That of US President Joe Biden Revision of nuclear posture the same month, it abandoned a “no first use” policy it had previously advocated. One could imagine nuclear risks in other conflicts as well, such as the possibility of North Korea using an atomic bomb against South Korea, or Pakistan and India using them against each other.
World arsenals amount to about 12,700 warheads, according to an inventory of Federation of American Scientists. That’s less than their peak of about 70,000 near the end of the Cold War, thanks to arms reduction treaties. But some of those the pacts have since been dissolvedand the dangers never went away, as the doomsday clock metaphor illustrates.
This is not a game, Drikakis says. The risks of a devastating nuclear attack are all too real, he says: “We must keep the peace by understanding the risks of not keeping the peace.”