Two types of swell; Ground swell and Wind swell
Chances are that a non-surfer friend has told you: “You should go surfing because there is a strong wind, there must be good waves!” Surfers know that it doesn’t quite work like that. The ideal playground for surfers include clean and powerful waves, without (on or side shore)wind. There are two types of swell (swell=series of waves). Ground swell and Wind swell. In this article we explain the difference between the two and how they are formed.
1. Ground swell
Ground swell is the best swell for surfers. As the swell has more power, energy and a better ‘wall’ to surf/play on.
Imagine when you throw a stone in the water, wrinkles are formed and keep on rolling even when the stone has arrived to the ground.
Ground swells are formed in a similar way, only in this case not by a stone but by a low pressure system. Which was active hundreds to thousands of kilometres/miles away from the coast. The depression causes wind, wind causes waves and when the wind keeps on for a while the waves become more solid and formed into groundswell. The distance between waves determines the power of the waves. Surfers call this the ‘period’ between waves. So the bigger the wave period, the more powerful the waves are.
There are three factors influencing the wave height: wind speed, wind duration (how long the wind blows) and the distance that the wind blows.
Faster waves catch up with slower waves and become a group of larger waves called set waves. These are the waves most surfers wait for in the line-up as these are the higher and more powerful waves. They come in intervals and very between 3 to 8 waves.
2. Wind swell
Wind swell is formed by local winds closer to shore. This results in usually choppy / messy waves. These waves didn’t travel far and didn’t have the chance to become solid waves. They might seem more consistent but due to the lack of power (small wave period) in them and messy conditions they are not the best for surfing. This doesn’t mean that you can’t have a great surf session! Every condition can be seen as a new challenge and practising in less ideal conditions can definitely improve your surfing!