Wave Seekers: Mathematician calculates the ‘sweet spot’ of a wave in La Jolla’s SIO


Like all surfers, Scripps Institution of Oceanography (SIO) post-doctoral student Nick Pizzo has been looking for the perfect spot on a wave since he started surfing at age 15. His research paper “Surfing Surface Gravity Waves,” published in the Journal of Fluid Mechanics June 16, defines that “sweet spot” in mathematical terms. The study explains “which particles on a wave are going to accelerate, and when they do, how fast they’re going to go,” Pizzo said. “As surfers know, the sweet spot is in the curl. It’s right underneath the lip of a breaking wave.

“These things are obvious to surfers, but the intent of the study is not to show things that are obvious to surfers, it’s kind of cool that there’s something people can fundamentally understand, but the idea (of the study) was to understand the currents that are generated by these breaking waves,” he explained.

What he loves about surfing is finding that high speed. “That’s the best part for sure,” he told La Jolla Light. “It’s because it’s that sweet spot, same thing when you’re getting barreled. That’s why it’s so exciting to be there, you have these huge accelerations that happen in the barrel.”

Pizzo completed his Ph.D. in 2015 at SIO, where he has been studying the physics of the ocean. “We want to better understand how the ocean and the atmosphere talk to each other,” he explained. “The way that they do it, is kind of the game of telephone with a little kid in the middle, which is the wave field. The wave field controls how the atmosphere and the ocean actually interact, which is something we care about a lot because we need to understand the dynamics of what’s happening to those waves, to understand how the atmosphere and ocean are in fact talking to each other.”

But blending his two passions wasn’t always his goal. “I was down in Brazil doing research in kind of technical areas of math, and I was kind of like, ‘I like this, but I’m not super good at this.’ It was kind of hard. So I said, ‘I want to do something a little bit more applied.’ So somebody mentioned, ‘You should check out Scripps (Institution of Oceanography).’ I’d never heard of it. I went online, checked out some of what people were doing here and I was like, ‘This looks fun.’ So I came here and decided that waves would be fun to study, also because of some of the science behind them.”

A native of New York, Pizzo first got hooked on surfing while searching for waves in hurricane swells. “And then I kind of just did nothing else for 10 years straight. I took a year off to travel just to surf. I surf here (in La Jolla) every day the waves are good, but it’s not as much of my life as it used to be,” he confessed.

Rather than trying to be a pro surfer, Pizzo concentrates on the fun of surfing. Two years ago, he said, he dumped his shortboard to ride a 7-foot 4-inch Christenson. “It’s been so liberating, you just go fast. I’ve ridden that in big Black’s Beach (surf), or two-foot Scripps’ waves, and it seems to go good in everything,” he said.

What’s in a Wave

“I teach graduate students, and I tell them, waves don’t propagate mass, they propagate energy,” Pizzo said. “A wave in general is anything that has a structure that propagates, so it’s a really abstract term. A wave can be a lot of things that you don’t think about as being waves. Basically, everything is a wave, we’re talking right now (and we’re producing) waves, we’re disturbing the air. We’re seeing things, these are light waves. It’s how your ear drum works, too, it’s like a little drum and the waves hit it. There’s plenty of examples. What we say in math is that, any kind of structure that’s coming in that we can follow, is something we call a wave.”

He said his favorite ocean wave is “Winky Pop,” a break near Bell’s Beach in Australia, one of the most famous surfing spots in the world and a common stop of the Surf World Tour. “It’s a long right hand point over a reef, and you can almost draw a ruler on how straight the lip line is, and it’s super fun!” he related.

“There are waves out here (in San Diego) that get quite big. Imperial Beach (before the sand replenishment) was really good one year, spinning barrels for a whole couple of months. When there’s a swell down in Coronado there are some pretty cool ones down there, it was fun to see those beaches light up like that. Black’s, when it’s big, it’s always pretty epic and terrifying,” he added.

But for Pizzo, surf is not only about speed. It’s also about life lessons. “I grew up in the water. I sailed and my older brother is a sailing coach. Being close to the water is pretty important to me. Surfing teaches you pretty explicit lessons all the time — like patience, humility — whether or not you listen to the lessons is probably a different story, but it seems like every time you go out at Black’s Beach when the waves are over 6-feet, you learn something. Even if you didn’t want to learn a lesson that day, you do. It’s a little bit humbling.”