The Wave Pressure Hypothesis

I watched the waves on Lake Erie at Buffalo on one windy day. The wind was roughly from the west along the length of the lake and the waves were much higher than usual. Yet, I wondered why the waves in the lake never reached the magnitude of the waves in the oceans. This got me thinking and led me to a factor in wave formation in bodies of water that I had never seen documented before.

It is well-known that moving air has lower pressure than still air. This is why an airplane flies. It's wings are curved on the top and flat on the bottom. This shape is known as an airfoil. It means that, as the wing slices through the air, the air above the wing will have to travel faster than the air below the wing. Since the faster moving air above the wing exerts less pressure on the wing than the air below it, the airplane becomes airborne when the difference in pressure exceeds the weight of the plane.

In older cars, before the advent of fuel injection, carburetors operated by the same principle to mix fuel vapor with air flowing through the air filter. The incoming air flowed into a narrow tube called a venturi, which caused the pressure of the air to drop because it had to move faster in order to move the same volume of air through a narrower tube. This drop in pressure in the venturi pulled fuel vapor in to mix with the flowing air, which than went into the engine's cylinders.

This principle of faster-moving air exerting lower pressure is relied upon in transportation technology. Yet, I have never seen it referred to in earth science.

There are two forces holding the earth's bodies of water in place. The first, of course, is gravity. The second is the downward pressure from the atmosphere above the water. The earth's atmosphere exerts a pressure of approximately 14 pounds per square inch at sea level.

But what happens when the wind blows across the water? Using this airfoil or venturi principle, (take your pick which you want to call it) the pressure above the water should be lower than if the air was still, right? My hypothesis is that an important but overlooked factor in the formation of waves in the oceans is this principle.

If the wind is blowing over a stretch of ocean but the air above the water some distance away on either side of the wind is still, that would decrease the relative atmospheric pressure on the water below the wind. That would logically cause pressure on the water to "pile up" in the windy area. This "piling" would help the wind to "catch" the water and thus would create larger waves than if there were no differences in atmospheric pressure above the water.

We already know well that a decrease in atmospheric pressure in the middle of a tropical storm pulls up water. This is the so-called "storm surge", a term that residents of New Orleans will never forget. This hypothesis may explain the impressive waves of the Pacific Ocean. The Atlantic is more stormy, the word "pacific" actually means "peaceful". But the Pacific Ocean is much larger than the Atlantic and so has more variations in the atmospheric pressure above it. This makes it possible for areas around the Pacific, such as California, Hawaii and, Australia to be famous for their surfing.