A physicist says blowing up nuclear weapons in the ocean to trigger tsunamis 'would be completely stupid'

British tabloids recently reported that Russia could trigger tsunamis with nuclear "mole" missiles buried near US coasts.
The claim was rejected by both nuclear weapons experts and the alleged source of the idea.
Underwater nuclear detonations can trigger large waves, but
it's nothing compared to natural tsunamis.

Nuclear weapons are as awesome as they are terrifying. In an instant, their explosions can vaporize people, level cities, and obliterate military forces.

But could this fearsome power be harnessed by Russia or other nuclear nations to lob deadly tsunamis against an enemy coastline, as British tabloids recently reported?

If you ask a nuclear physicist, you're likely to be laughed out of the room.

"It would be a stupid waste of a perfectly good nuclear weapon," Greg Spriggs, a nuclear-weapons physicist at Lawrence Livermore National Laboratory, told Business Insider in an email.

Here's why it doesn't make sense and where the myth came from.

The science of nuclear wave-making

A nuclear weapon detonated below the ocean's surface can cause great devastation.

One need not look further than the underwater US nuclear weapons tests of the 1940s and 1950s, including operations "Crossroads Baker" and "Hardtack I Wahoo" to see why. These underwater fireballs — roughly as energetic as the bombs dropped on Hiroshima or Nagasaki in August 1945 — burst through the surface, ejecting pillars of seawater more than a mile high while rippling out powerful shockwaves.

Some warships staged near the explosions were vaporized. Others were tossed like toys in a bathtub, sinking them. Others sustained crushed or cracked hulls, crippled engines, and other damage from the shockwaves. And — notably— the explosions roughly doubled the height of waves to nearby atoll islands, flooding inland areas there.

Yet Spriggs says it's unlikely that even the most powerful nuclear bombs could come close to unleashing a significant tsunami.

"[T]he energy in a large nuclear weapon is but a drop in the bucket compared to the energy of a [naturally]-occurring tsunami," he said. "So, any tsunami created by a nuclear weapon couldn't be very large."

"And second, because of the small solid angle that would subtended by a nuclear-induced tsunami (in the direction of the shoreline), most of the energy would be wasted going back out to sea," Spriggs said.

Perhaps the most damning point against using nuclear weapons to trigger tsunamis is how much more effectively the same weapon could kill people above-ground.

"[I]f they dropped a 10 MT weapon directly over a city, they could kill millions of people as opposed to a small nuclear-induced tsunami that may, at best, kill only a few thousand people that may be within a few thousand yards of the beach," Spriggs said. "In short, I don't believe it."

The origins of the nuclear-tsunami myth

The claim that underwater nuclear blasts could trigger devastating tsunamis appears to have started with and spread by some media outlets in the UK.

Those stories referenced a commentary piece by Viktor Baranetz, a former spokesman for the Russian Defense Ministry, that was published February 28 in Komsomolskaya Pravda, a Russian tabloid. At the time, Baranetz was responding to President Donald Trump's desire to increase US military spending by $54 billion, on top of an annual budget of about $600 billion — what he claimed is roughly 10 times that of Russia's yearly military investment.

According to a March 8 translation by the Middle East Media Research Institute, Baranetz suggested that Russia has "already found asymmetrical responses" to counter such US military might including, for example (our emphasis added):

"[N]uclear warheads that can modify their course and height so that no computer can calculate their trajectory. Or, for example, the Americans are deploying their tanks, airplanes and special forces battalions along the Russian border. And we are quietly 'seeding' the U.S. shoreline with nuclear 'mole' missiles (they dig themselves in and 'sleep' until they are given the command)[...]"

Starting around April 30, however, several British outlets — including the Daily Star, Daily Mail, Telegraph, and The Sun — wrote that Baranetz claimed such "mole" missiles could detonate underwater to trigger deadly tsunamis against US coastal targets.

But Baranetz's text doesn't mention underwater detonations or tsunamis. In fact, he wrote a piece on May 2 that decried the suggestion of nuclear tsunamis as a "lie". (Business Insider contacted several prominent British outlets that published the nuclear tsunami claim; in response, at least one publication removed all references to the idea in its story.)

In his follow-up commentary on May 2, Baranetz also clarified the suggestion of "mole missiles":

"In Russia, any student who owns a computer will explain that 'Status-6' is a Russian project of an unmanned nuclear submarine. The mission of the apparatus is to deliver a nuclear munition with the aim of destroying important coastal elements of the enemy's economy and inflicting guaranteed unacceptable damage by creating extensive zones of radioactive contamination."

The Kremlin quickly and roundly denied Baranetz's claims, according to a piece by Tom O'Connor at Newsweek, and experts doubt the existence of "mole" missiles.

However, this does not change the reality that US and Russia together have deployed more than 3,700 nuclear warheads, with many thousands more stockpiled. Where many of the deployed weapons are at a given moment is either country's guess, given submarine and other covert military technologies.

Elena Holodny contributed Russian translation assistance for this post.