What the surface reveals about what lies beneath.
Surfing lets us explore the unknown. The element of the unknown has always drawn us towards the water and is one of our favorites things about paddling out. Many modern sports have painted lines on the field and a set amount of time for each half or quarter. The length of the field is fixed and the ground is fixed beneath your feet. For these types of sports, there is not much unknown except who will win and who will loose. Surfers, on the other hand, play on a field that covers 71% planet; of which only 5% has been explored by humans. There is no set time for a surf session and the water is constantly changing underneath your board. The ocean floor can consist of a variety of things; ranging from reef to rock, to sand, to a combination of these.
Surfing doesn't come with a hard and fast rule book like many of there sports, it is up to you to understand what the ocean is telling you and heed its warnings. The modern surfer is part oceanographer in addition to being athletically fit. In today's world, a surf starts with checking the forecast online to see size, tide and wind conditions. If the forecast shows promise, then its packing up the boards and seeing what the break is actually doing.
Surfing 101 - Reading Waves
When we pull up to our favorite break and start to see the lines rolling in, our evaluation of the day's waves has begun. Even at our home break, where we have surfed dozen's of times can produce dramatically different conditions depending on the swell angle, tide and build up [or depletion] of sand bars. Its important to pause for a moment and gauge the conditions.
As you sit on the beach before paddling out, look out for potential opportunities and hazards. In the photo above we've spotted some 'boils' in the water. These boils are caused by tall protrusions on the bottom which translate to shallower water. Often Coral Heads or Large Rocks. Waves break as the swell energy moves from deeper to shallower water, causing friction which slows the wave face down causing the top to topple over [break]. If you are surfing over rock or reef you will likely be surfing on or next to boils like this. Be sure to know what the tide is doing as on a dropping tide the tops of the coral heads or rock could become exposed and cause injury.
Understanding Whats Below The Wave
As the image explains, the breaking whitewater is in the most shallow area of the reef. Just next to the white water is the 'power section' of the wave. This is also called the 'pocket' and is where the most energy is. Under the water, this part of the wave is hitting shallower water and causing it to 'stand up'. The more slopey face to the far left is where the water is deeper and thus the wave has not had the friction to stand up.