This is a summary of the Nautilus Magazine article by Adam Piore.
In 2016, world champion surfer Kelly Slater, with the help of aerospace engineers, created the best surfing wave in a central California artificial lake.
Laboratory mimicry of nature has exploded in recent years, and extended itself to waves. However, the secrets of these waves are fiercely guarded at the moment. We do know for one thing that one of those wave machines's first version involved a sloped rubber mat.
Waves are formed when the wind transfers momentum to the sea surface, causing water molecules to circle in place and transfer their momentum to the molecules next to them, in turn causing them to circle in place, and so on. It is the energy that is transferred, not the mass. Mass remains mostly in place, whereas energy travels a comparatively much longer way.
The 'fetch' is the length of open space over which the wind generates waves every time water rises at an angle to the wind. Energy also dissipates downward, with the circling water molecules moving in exponentially smaller circles with depth. Near the coast, the energy does not completely dissipate in the depths, because the bottom is closer than the dissipation depth, so that the energy concentrates, making the waves taller and taller until they break. How the waves break depends on the shape of the bottom.
Dream wave parks already exist where a machine generates static waves. The experience differs from the ocean : Artificial waves have troughs that move away from the surfer, whereas in ocean waves, the trough water moves towards the surfer, making for a more intense dynamic experience in the artificial wave.
New waves are also created by computer, using algorithms relying on water and air temperature, gravity, air pressure, elevation, water viscosity, and the boundary shapes of the wave pool. One of these computer wave simulators makes not only peeling waves, but also peaks, mushy and barreling waves. Another one uses a one-twelfth scale model to test computer simulations. In water chambers at the back of the pool, compressed air pushes water down, causing circular molecular motion like in the open ocean, causing waves to exit the chamber and roll across the pool.
Outdoor surf parks rely on similar technology in artificial lakes with custom bottoms, some with a hydrofoil built to sculpt the wave shape, some with the hydrofoil moving at an angle. Surf parks with artificial waves are making efforts to attract surfers of all experience levels, but for surfers, the energy and barrel of the artificial wave competes with the unpredictability, mysticity and sacredness of the open ocean.
