Surfing Meets Science

Surfing Meets Science

Finding a Wave’s “Sweet Spot”

On a recent family trip to Cocoa Beach, I found myself body surfing in the midst of the relaxed, Atlantic waves off the East Coast of Florida. Surfing anywhere can prove to be a challenge, as it’s difficult to learn the ocean’s rhythm and catch some waves in the process. Any good surfer will tell you that the key is to jump into a wave’s “sweet spot.” After years of Floridian beach-going experience, I’ve personally found that the sweet spot is right below the crest of the wave, just before it breaks into a rolling white foam. The majority of surfers will agree that positioning yourself within this spot is critical for catching the ocean’s waves and having a successful and enjoyable surfing experience—And it turns out that scientists agree too.

In a June 2017 study published in the Journal of Fluid Mechanics, physical oceanographer Nick E. Pizzo identified the sweet spot of a wave, the point where the water particles “surfing” the wave accelerate the fastest. Pizzo’s study confirms that this sweet spot is located “below the crest on the forward face of the wave”.1 A surfer himself, Pizzo was interested in scientifically confirming what his experience on the water had already taught him about waves.2

Pizzo’s research first sought to understand the criteria necessary for particles to “surf” a wave. That is, what conditions allowed for a water particle to catch a wave and experience an increase in its velocity.  Pizzo derived an equation created by Fritz John, originally intended to describe the movement of particles in stress-free conditions, to mathematically model the movement of particles surfing a wave. He discovered that a particle must be traveling around the same speed as the wave for it to “catch the wave.” He then applied this criterion and his derived acceleration equations to a theoretical wave to model where the point of maximum acceleration is actually located. He found that the sweet spot is located right under the crest of the wave, also known as its “curl.” 1

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Pizzo’s findings come as no surprise to himself and other experienced surfers. However, his study is the first to scientifically confirm the “sweet spot” of a wave, validating knowledge that surfers have been taking advantage of for years. His work was inspired in part by a well-known physics principle called Landau damping, a phenomenon that describes how charged particles can “surf” electric fields within plasmas upon meeting certain conditions.1 The researcher successfully showed that this surfing phenomenon can occur in many other forms than just electric fields.

Ultimately, there are many implications for Pizzo’s research besides the sport of surfing. As members of the Air-Sea Interaction Research Lab at the Scripps Institution of Oceanography, Pizzo and his fellow researchers can use their mathematical identification of the sweet spot to further their understanding of the kinematics behind breaking waves. Breaking waves dramatically impact the thermodynamics, chemistry, and currents of the surf zone near the world’s coasts, meaning Pizzo’s findings could lead to a better understanding of our coasts and their integration with other earth systems.1 Furthermore, his work has the potential to improve global climate models, which rely upon sensitive measurements affected by the currents of breaking waves.2

Next time you head to the beach, keep Pizzo’s research in mind and remember to shoot for the curl of the wave when surfing. After all, science says so!

Works Cited:

  1. Pizzo, Nick E. “Surfing Surface Gravity Waves.” Journal of Fluid Mechanics 823 (2017): 316-28. Print.
  2. Wood, Lauren. “A Wave’s ‘Sweet Spot’ Revealed.” Scripps Institution of Oceanography. N.p., 29 June 2017. Web. 13 July 2017.