Slab surfing refers to surfing on a wave that is described as a “slab” wave. This type of ocean wave is different from others in that it is actually formed in the deeper depths of the ocean, rather than closer to the surface as many waves are.
Once a slab wave does reach the ocean surface, it does not rise. Rather, its motion is described as one which takes in all the water in its path. From there, rather than forming a wall, as other oceans waves might as they rise, a hole appears in the wave. It is these holes that those who participate in slab surfing try to ride.
A combination of things must occur in order for a slab wave to even form. Wind and swell conditions must be just right. Even then, the water level on the ocean floor itself, which is constantly changing, must be compatible with the wind and swell conditions. For this reason, slab waves are not very common.
As with any sport, new ways of experiencing surfing come and go. Slab surfing was not very popular for quite a while, but started to see a resurgence in 2000. Since then, as more and more surfing enthusiasts tried their luck at slab surfing, and recorded their efforts, and continue to do so, it has become even more popular.
The object of slab surfing is to surf the hole in the slab wave for as long as possible before the lip of the wave starts to come over. If a surfer is still in the hole when the lip curls, he or she can be violently tumbled about. When this occurs, injuries from striking unseen objects in the ocean, or from being tossed unceremoniously on the shore, can happen. These can include broken bones, abrasions from the rough contact with the sand, and other injuries.
But, perhaps that is what makes slab surfing so exciting. Just as one never knows when the next good slab wave is going to come along, neither does the surfer know what will happen if he catches it and rides the hole.