Whether you’re a boater, a landlubber or somewhere in between, the fact that the sea has incredible and practically unparalleled power should come as no surprise. Between the force of the ocean current and the tidal power, water carries a truly astonishing amount of energy.
It’s because of the profound amount of energy that water carries that it is such an exciting, rewarding and, at times, terrifying mode of transportation. Boating would not be nearly as enjoyable if it took place on a more docile and easily predictable means.
However, while the power of the sea imbues boating with a truly thrilling and unpredictable element of fun, it is something that every boater needs to both be aware of and attuned with. Your enjoyment of the water needs to be tempered by also maintaining a healthy respect for it.
One of the easiest ways to tell that the ocean can be as capriciously tempestuous as it can be driven is by considering the idea of wave measurement. While the movement of the water is constantly reflected in the pitch, yaw and roll of the boat, measuring wave size is not necessarily an easy, set or precise process.
Before we discuss how to measure a wave, it’s first important to understand exactly what they are: waves are much more than adrenaline-pumping things to catch. They are, scientifically speaking, the result of wind passing over the surface of the water. Essentially, the wind frequently (but not always) travels faster than the waves can propagate, which results in an energy transfer between the water and the air. This transfer, which occurs due to the differences in air pressure and surface friction, puts stress on the water and incites the growth of waves.
When it comes time to try and measure the actual growth, or, to put it more plainly, the actual height of the wave, there are a variety of factors to consider. Wave height is measured by the speed of the wind, the time period the wind has been blowing, fetch (the distance for which the wind has been exciting the waves), and by the depth of the water and the topography of the ocean floor. As you may have noticed from this definition, simply being out on your boat and trying to get a solid visual estimate of wave height is not a simple matter.
This because many of the factors used to precisely calculate wave height are not elements that lend themselves well to being easily and quickly estimated. In point of fact, there are few things that are as notoriously unreliable as a sailor’s memory. From Moby Dick to Christopher Columbus’s report of the New World, sailing fold tend to have a fairly loose relationship with the truth. It is for this reason that it’s easy to ride out a particularly nasty wave set and then turn to your passengers and ask them what they thought of those three footers, only to have them report, very emphatically, no less, that those waves were at least four footers.
This tendency to have several versions of the same truth is, when you consider the actual mechanics of eaves, quite understandable. One of the biggest obstacles that prevent us from getting an accurate wave height estimate is our perspective: it’s always hard to have the distance you need to truly understand the area through which you’re navigating when you’re right down in the trenches (literally) of the area you’re trying to understand.
Even the National Oceanic and Atmospheric Administration reports wave height according to a fairly expansive range of potential heights. It’s rare that you’ll check the news before you go out and hear that the weather is sunny with one foot waves. Instead, it’s far more likely that you’ll hear the weather is sunny with six inch to two feet waves.
Part of the reason that even the experts assign wave ranges as opposed to hard and fast numbers is that thanks to the very forces that are responsible for engendering wave in the first place are just as variant. Wind speed can change on a dime and, so too, can the size of a wave.
What’s more is that there is nothing more difficult than trying to guess the height of the wave when it’s the same wave that’s rolling and pitching right beneath your feet! When this happens, you’re not looking at the wave’s crest from a right angle, which skews your ability to accurately assess its size. Another thing that makes measuring difficult is the different impacts the direction of your sight can have on your ability to adequately gauge a wave’s direction and true size. For example, when a wave is coming at you, it will both look and feel bigger than it actually is. On the other hand, if that same wave happened to be moving away from you, it would be smaller than it actually is.
Ultimately, wave height is an incredibly powerful and relative phenomena. Always remember that it’s more important to respect the water than it is to try and measure it. When you take the time to prepare for an outing, you will most likely find yourself much better suited to handle the force of the water, no matter the size!
“Image Credit: wikimedia.org“