Wondering how you can catch the perfect wave? Dive into the fascinating and complex physics of surfing.
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Whether or not you realize it, surfers are masters of complicated physics. The science of surfing begins as soon as a board first hits the water. Surfers may not be thinking about weather patterns in the Pacific, tectonic geology or fluid mechanics, but the art of catching the perfect wave relies on all these things and more. Nick Pizzo dives into the gnarly physics that make surfing possible.
00:00Whether or not you realize it, as a surfer, you're a master of complicated physics.
00:13The science of surfing begins as soon as you and your board first hit the water.
00:20The board's size and light construction help it displace a lot of water.
00:25In turn, a buoyant force equal to the weight of the displaced water pushes up,
00:31counteracting you and your board's weight.
00:34This lets you stay afloat while you wait to paddle for a wave.
00:38And what exactly are you waiting for?
00:40The perfect wave, of course.
00:42Like other waves in physics, ocean waves represent a transfer of energy.
00:49Wind blowing across the ocean accelerates water particles near the surface,
00:54leading to the growth of ripples that become waves.
00:58These deviations from the flat surface are acted upon by gravity,
01:02which tries to restore the surface to its original flat state.
01:08As the waves then move through the water, particles push and pull on their neighbors
01:13through the wave-induced pressure.
01:15And this motion propagates energy through the water in unison with the wave motion.
01:21The motion of these particles is much more limited than the overall motion of the waves.
01:27Near the shore, the shallower seafloor constrains the motion of the waves to occur in a more limited region than out at sea,
01:35concentrating the wave energy near the surface.
01:38If the topography of the shoreline is even and smooth, this will refract the waves to become more parallel to the shore as they approach.
01:47This is the crucial moment.
01:50As the wave gets near, you quickly pivot your board in the same direction as the wave and paddle to match its speed.
01:57Your board forms an angle with the water, and this creates a dynamic pressure on the bottom of it,
02:04forcing you and your board out of the water to skim along the surface.
02:09At the same time, your increased forward momentum makes you more stable, allowing you to stand up and surf along the wave.
02:18Now you've caught the wave and are riding along its front face parallel to the shoreline.
02:24Fins on the surfboard allow you to alter your speed and direction by repositioning your weight.
02:30Above you is the wave's crest, where the water particles are undergoing their greatest acceleration.
02:37That forces them to move faster than the underlying wave, so they shoot ahead before falling under gravity's influence.
02:45This forms the wave's characteristic curls, or jets, as they break along the shore.
02:51Sometimes the curl might completely enclose part of the wave, forming a moving tube of water known as the barrel.
02:59Because of irregularities in the seafloor and the swell itself, few barrels last as long as the legendary 27-second ride off the coast of Namibia.
03:09But many who manage to get barreled have said they feel time passing differently inside,
03:15making it one of the most magical experiences a surfer can have.
03:20Of course, not all beaches are created equal.
03:23Offshore underwater canyons or rock formations in certain locations like Nazare, Portugal or Mavericks, California,
03:31refract the incoming wave energy into a single spot, creating massive waves sought by surfers worldwide.
03:39And some of these waves travel for more than a week, with swells originating more than 10,000 kilometers away from shore.
03:48Waves surfed in sunny California may have originated in the stormy seas near New Zealand.
03:55So, while you may not be thinking about weather patterns in the South Pacific, tectonic geology, or fluid mechanics,
04:02the art of catching the perfect wave relies on all these things and more.
04:08And the waves we surf, created by wind,
04:11are just one visible part of the continuous oscillation of energy
04:15that has shaped our universe since its very beginning.
04:19Despite its association with fun and sun,
04:22surfing has a richer, deeper, and much more complicated history than many realize.
04:27Check out this episode to uncover the hidden history of surfing.
