Surfing Waves

I swear that this is true. Except for when you pass on the first one, and there just is no second one.

I was kind of joking but...

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"So the engineers sat down and studied the equations that govern wave motion. They found that certain (very tiny and usually neglected) nonlinear terms in the equations of motion of deepwater waves act to transfer energy (very slowly) from the leading and trailing edge of a set of waves, toward the center waves. Thus the central waves get bigger at the expense of leading and trailing waves."

-http://www.surfingvancouverisland.com/weather/wave.htm

this can be true. It really depends. I try to look for the cleanest line that will produce the best ride. I dont care whether it is the first or last wave in the set.

1st wave of the set - no problems with backwash, can be a touch cleaner, gonna be dozens of people on it if there hasn't been a wave for a while, leaves you caught inside.

2nd wave of the set - probably significantly bigger, everyone knows its coming - gonna be crowded, still going to leave you caught inside.

3rd (last) wave of the set - you know whats going on now, might be bumpy, last chance - everybody goes for it, first two waves have cleared the line-up a little bit, not gonna get caught inside and an easy paddle back out.


Pros and cons - make your choice.

coldhands wrote:I swear that this is true. Except for when you pass on the first one, and there just is no second one.

Ok this is quite a complicated issue as it doesn't always hold true due to the random nature of sea states and overlapping wave sets of differing frequencies and periods.
However if you look at one particular wave set that is not being influenced by any others the following is true.
The middle wave of a set of waves will be bigger in amplitude than the ones at the back and the front.
When you see waves approaching what you need to remember is that the water in the waves are not travelling towards but are in fact only moving up and down vertically. Until the wave breaks of course and then some different physics take place. It is the energy in the wave that is moving towards you. Wave sets are born by waves of simillar periods grouping themselves togther with the same wave length and hence wave velocity. If you watch sets of waves travel through deep water you will see that a wave will be born at the back of the group then travel forwards through the set getting bigger as it goes and then disappearing at the front. In fact the waves in the group travel twice as fast as the actual speed of the group of waves. If the individual waves in the set didn't travel faster than the overall speed of the group of waves then the wave energy wouldn't propergate forwards.
As the group of waves approaches shallow water the front waves will slow down before the waves behind and the wave height increases dramatically and the phenomena becomes noticeable. The reason why we as surfers don't see waves at the back of the set travelling to the front is because it is a property of deep water waves but the transistion from deep to shallow is fast enough and means that the group of waves retains the wave profile it had in deep water of the waves at the front and the back being smaller than the ones in the middle.

KS