Rogue waves are little known and can kill. Here’s why they’re so dangerous

It was supposed to be a relaxing day full of tacos, swimming and watching people surf. But it almost ended in tragedy. Noah Mintz was on a trip to Sayulita, Mexico with his ex-girlfriend and went swimming at the beach. The water seemed to be good.

As he made his way back to shore, with water up to his knees and the ocean on his back, he was knocked over by what was probably a fake wave.

“I was just lying flat in the water, face down, unable to move,” said Mintz, 54, of Toronto. “I just thought, ‘This is it. This is the moment. I’m going to die right now.'”

A rogue wave is characterized as one that is 2.2 times larger than the average wave around it. They can be deadly and take people by surprise. They can occur when ocean waves collide and merge to create a larger wave, according to research published by National Geographic.

According to the USA National Ocean Servicerogue waves can also form in a storm, when regular waves move against the typical direction of the current and merge with others into one large and long-lasting wave.

While the number of rogue waves is hard to quantify — no organization tracks them or injuries from them — Mintz is far from the only one who has experienced their power. One of the biggest waves recorded so far was not far from the coast of BC

Johannes Gemmrich, who studies these waves, says there needs to be more awareness of what they can do.

Most people imagine a rogue wave as something that might hit a cruise ship or ship in the middle of the ocean. But they are more than that, he says.

“I don’t think most people are aware of rogue waves, especially not that they can also occur in the coastal area where most people interact with the ocean,” said Gemmrich, an oceanographer at the University of Victoria.

Wave power

As Mintz lay face down in the water, he recalled key moments in his life, wanting to find the perfect one to focus on as he died.

Fortunately, he didn’t have to. Instead, his ex managed to find him in the water and flip him over. He was then lifted onto a surfboard and taken to shore, paralyzed but conscious.

“I know you shouldn’t turn your back on the ocean, but I didn’t think so,” Mintz said.

His neck was broken in two places, along with several scratches and cuts. After surgery and several months of rehabilitation, he managed to fully recover, except for minor nerve damage on his left side.

He was able to re-emerge relatively unscathed from his experience. But this is not always the case.

Mary MacNutt, Tassie Notar and another friend were on vacation in Chacala, Mexico in December 2023. They had just arrived, and MacNutt and Notar, then 66 and 70, wanted to go swimming.

There were waves, so the couple decided to move down the beach to find a calmer area. But while Notar and MacNutt, both from Toronto, were enjoying the sun and ocean, a big wave started coming toward them.

“This wave was an aberration. This wave was a monster wave,” said Notar, who estimates it was about four meters high. “It was so high. And we both turned around and immediately started swimming to shore.”

They didn’t know what to do. The wave was coming fast, and they weren’t close enough to shore to turn back.

After the wave hit, Notar couldn’t find her friend. She ran to the beach, shouting for help, but no one moved. Then she turned and saw someone on the beach giving MacNutt CPR.

We didn’t know it then, but she was already a quadriplegic, Notar said.

A few weeks later, she was airlifted to Toronto. She needed support to breathe and was told it was unlikely she would get better. She asked to be taken off life support and died on January 7, 2024.

“She reassured me the whole time. She said, ‘I’ve had a very good life. Don’t worry, I’ve had a very good life’.”

What could be done?

The notary wonders what else they could have done when they saw the wave and if there was any way to avoid it.

Gemmrich, the oceanographer, says that if it’s far, you can try to reach the shore. But even that is difficult, because he moves much faster than any swimmer can.

“The best way is to actually dive into it. So, wait until it gets close, or back away slowly, but when it gets close, dive into it, because the force decreases with depth.”

And instead of trying to avoid it, Gemmrich says the answer is early detection.

Early warning system

The study of rogue waves began in the 1990s, when one such wave was measured by a drilling rig with scientific equipment. Before that, they were considered fairy tales told by sailors.

“Even scientists thought it was not possible to have a wave twice as high as the background wave,” Gemmrich said.

Spurious wave research was initiated in the early 2000s. In 2020, what some consider to be the most extreme rogue wave ever recorded at 17.6 meters high, off the coast of Ucluelet, BC, far above the average six meter waves around it.

Gemmrich studied exactly this wave. He says a rogue wave usually happens every few days, but if it’s small or there aren’t people or boats around, no one notices.

And while the risk of it forming at a height and location that would cause danger to people is small, Gemmrich says it’s important that people are prepared.

That is why he is developing an early warning system. He cannot predict exactly where and when a false wave will form, but he can predict when the conditions are ripe for it.

Forecast wind patterns for the next few days are needed, along with ocean wave physics. It can then predict the creation and evolution of the wave field. He wants it implemented in regular forecasts.

“That model is now working as a research model and will be transferred to Environment and Climate Change [Canada] in the near future to bring it into the public domain of prediction,” Gemmrich said.

The notary wishes there were better signs when she and MacNutt went swimming. He is still pushing for better signs near the resort where they stayed, specific to rogue waves.

“The rogue wave, to me, I think if people don’t know what it is, it sounds scary. And it’s different than a red flag on the beach,” Notar said.

Mintz learned from experience. He is not afraid of the ocean and is still ready to go swimming. But he is a little more careful on the beach.

“Like when you’re dealing with a wild animal, it’s completely unpredictable. And you never turn your back on the ocean until you’re out of it.”