Do waves move at the same speed (regardless of height)? How fast do they move? Has anyone measured their speed while surfing waves?
4,800,000
in 0.05 seconds. google- wave dynamics
http://www.seakayak.ws/kayak/kayak.nsf/NavigationList/NT0000C07A
steve
Not sure it’s all true but commonly
– Last Updated: May-18-05 11:08 PM EST –
people say average ocean waves close to shore travel about 10-15 mph, to catch a large wave >30' you need to be towed about 30 mph. Tsunami's travel at high rates of speed supposedly 500-600 mph. The crest is so wide however you wouldn't notice it if you were out on the ocean. There were some kayakers here in san diego who had the Indonesian Tsunami pass under them and did not notice. As a wave encounters the bottom as it comes to close to shore it will interact with the bottom and slow down.
http://www.geocities.com/surfer_ed/california.html
Another aspect of an ocean wave is if it peels as it breaks ... take a look at some of the shots in this link at
huntington beach, Scripps/lajolla shores and cardiff reef. The waves at the first two sites are peeling very quickly, the one at Cardiff is pretty fast. If a wave starts to barrel you can pick up tremendous speed. On a surfboard or a fast waveski an expert can go about 35 mph in the curl of a fast breaking wave. A whitewater kayak surfing can't keep up with the speed of the breaking wave. Really fast glass surf kayaks can do pretty well. Real surfing means riding in the power pocket as the wave breaks and peels. Surfing along the wave not perpendicular to it. If you get on a big wave and surf it you feel like you are really flying over the water, the sensation of speed is much different and more intense than riding in a car or on skis for me. The biggest wave I have ever surfed is probably about 12', the fastest I have gone is on a smaller barreling wave in the curl, it was fast but nothing like 35 mph.
GPS
– Last Updated: May-19-05 12:28 PM EST –
I was surfing some waves in a bay two weeks ago and my GPS showed a max speed of 8.5 mph.
I think the wind was blowing around 20 - 25 mph.
GPS
in the Columbia gorge on a big day (+35kn), I have logged 10.5 knots surfing windwaves.
deployed skegs generally start to vibrate at about 6-8 knots. IMO, a cool thing!
steve
GPS
21 mph Cardiff Reef …
(The max speed also has the largetst uncertainty of any measurement on a GPS so I would not put a lot of weight on it.)
That Is What I Heard, Also
That is about what I have been told also. Really large waves, over 20’, do about 30MPH. Under 12’ close to shore is only about 10-15 MPH.
It seems faster, but on a long ride when there is a second to observe, you can tell you are not going nearly as fast as it feels.
Period (length) determines speed
Not height. See link below.
cool
very good info and more than most want to know!
steve
My “Questions” About Waves…
When, where and how big? 
Speed? Don’t know. Just know that when I have a head high set with 10 second or more interval, I feel like I am flying with a lot of room ahead me to play. The stuff of stoke.
sing
As the water depth changes, wave speed
changes. The speed in shallow (ocean) water increases as the square root of the water depth. The energy in a wave is relatively constant. Both speed and wave height contribute to the energy. As a wave comes into shore, the smaller velocity in the shallower water must be offset by the wave getting bigger. In very shallow water, the top of the wave sees a bigger depth and is going faster than the bottom. When the wave can’t hold, but breaks, you get surf.
I measure wave height from the middle to either the crest or the trough (half height or amplitude) , except when I’m looking up at it. Then I measure from the bottom all the way to the top!
Cool Link
Challenging visuals needed to comprehend some of the info. Intersting that in open deep water, individual waves move at about 3 times their interval. That is an individual wave with a 15 second interval is moving at about 45 knots. But just as interesting is that the wave set is moving at about half that speed. The individual waves move from the back of the set to the front then dissapear and form again at the rear! When the get to shallow water, they all move at the same lower speed of the set.
Personally, I prefer the measurement of the wave face since that is what I will be dealing with in either punching out or getting back in. If you are in the wrong spot, and wave with an 8-ft face dumps on you, it still dumps from 8-ft. Does not matter if it is only a 4-ft wave from the back. Since the back of waves have a much gentler slope, they are even harder to estimate from on the water than the face. It also seems to make sense that non-breaking deep water swells have the same depth trough in front as in back. I agree the most important part is that everyone you paddle with is on the same page.