How to Understand Waves for Surfing

Surfing is one of the best sports out there with a great history and an even better future, but to harness the power of the ocean you must first know the anatomy of a wave.

The most common source of waves is wind action in the open ocean. Earthquakes and volcanic eruptions beneath the ocean can cause seismic sea waves, but these are rare. Storms in the open ocean, on the other hand, are quite common and result in variations in air pressure to force gusty winds upon the ocean's surface. If the wind is strong and steady enough, it will form chop over a large area, referred to as a sea. As these wind waves are blown downwind, they become longer, smoother, and more organized, taking the form of what is known as a swell. A swell is what we recognize as the marching lines of energy that travel across the open ocean. Swells can travel thousands of miles without losing much energy until they hit shallow water on our shores to form a breaking wave.

California's surf is a result of north, northwest, west, southwest, south, and wind swells.

North and northwest swells are produced by storms in the North Pacific in the winter months and are the largest and most powerful.

West swells are created by storms in the West Pacific and are most common in fall and spring.

South and southwest swells are generated by storms in the South Pacific in our summer months and can also result in strong and good-size waves.

Wind swell is a term used to refer to less consistent and usually smaller waves that are produced by storms or strong winds within a couple of hundred miles of our coast.

Waves generated by the wind may range in height from less than an inch to as much as 60 feet. The size of ocean waves is determined by wind velocity, the size of the area affected by the wind, and the length of time the wind blows. Big surf is made by large, long-lasting storms with strong winds far out at sea. Surf forecasters today can precisely determine when large waves will hit a particular spot on the coast by using weather data and computer models.

The highest part of the wave is called the crest or peak. The lowest part is called the trough or pit. The front of the wave is called the face, while the back is generally referred to as simply the back.