What Makes Waves?

Some are small. Some are tall. Some lap at our feet. Some knock us over. Some destroy entire cities…towns…islands…and cultures. If we’ve ever seen the ocean-or any other relatively large body of water- we’ve seen wave as well. We see all different kinds, with all different velocities and looks and heights. And oftentimes, we’re more inclined to play in or surf them, rather than ask ourselves…what makes waves? What even are waves?

            In high school physics class, most of us learned about energy (or definitely should have, at least). When we learned about energy, we learned that it moves in waves. All energy possessed different wavelengths, with different heights or crests, but regardless, we learned that all energy moves in this pattern of a wave.

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            Energy is everywhere. It’s in the air, on the ground, in the plants, the animals, ourselves, and anything around us. It’s constantly moving. This holds true to water in the ocean. Given that the Earth is made up of 71% water, whether it be in oceans or lakes, it’s only logical that this constantly moving energy must logically move through the seas as well.

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So it does, and we see it through this perfectly visible medium that is ocean water. Regarding this type of water though, out in the ocean, the waves aren’t typically, actually moving anything- the water remains relatively stationary. What is seen then isn’t necessarily the water moving…but rather, the energy moving. So where does this energy even come from?

Most of the time, it simply originates from the wind. As this wind blows, it collaterally disturbs the surface of the water. And as it continues to blow, more friction is manifested, more continual disturbance is created, and the wave crests continue to rise and rise until the water is higher and waves are effectively created. These types of ocean waves, transferring energy along the water’s surface, is inherently known as surface waves, or wind-driven waves.

            However, as we’ve all probably heard at some point in our lives, the gravitational pull of the moon and the sun cause waves as well. These waves, caused by this gravitational pull and the rotation of the Earth, are generally refereed to as tidal waves.

            With all of this information combined, it only makes sense that tsunamis (which are, despite common belief, not the same as tidal waves) are the same as this typically transferring energy. However, when something such as a landslide or an earthquake contributes an unexpected mass amount of energy to the ocean water, it largely contributes to the waves that are already moving, therefore…simply…creating one massive wave.

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What causes waves to break along the shore though? Well, this energy wave does not only move along the surface of the water. It also moves along the ocean bottom. As the sea gets shallower and shallower toward the shore, “the drag on the wave’s bottom becomes stronger”, and in turn, “the upper part of the wave begins to tilt forward,” as it continues to move at its regular, faster speed. And therefore, the wave as we know it, and the wave as we enjoy it, is created.

As for those waves that are so common to Beaver Stadium? They’re instigated by energy as well- however, it’s main source is often reported to be the pride of Nittany Nation.

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