Jimmy Blears was telling me something like that when he was working at Ala Moana park just before he retired. He believed in the face height system as most lifeguards do because they are the ones who have to save the people who go out when they shouldn’t.
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in the above x is sea level - you don't measure the trough! and the wave height is not the "peaking" height [/quote]
I don't know where you got that graphic from, but it is inaccurate. The trough of most waves is never below sea level.
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that graph is from wiki, but it is how all waves in science are measured
Of course the trough is below sea level. If it isn't where does the water above sea level that make up the waves come from? it doesn't just appear from nowhere, the volume of water in the sea doesn't change.
Any volume of water above sea level in the wave is equal to water taken from below sea level to create the wave.
as for the slope of course - it's simple pythogaras theorem.
1 wrong
and
2 wrong.
Ocean waves adhere to the principles of other types of waves, generally. The exception being the wave form as it pertains to the medium.
A swell in open water, which is called a deep water wave, exerts equal energy above and below the surface. When a swell passes a stationary object that is floating, the object will move forward, up, and back in a near circle. Place a buoyant object that is tethered below the water’s surface, and that will also move in the same circular pattern. The waves we ride are that portion of a bundle of energy moving through the water that is above the surface. It’s the reason waves break. The energy under water is attenuated by the sea floor. The upper part of the wave retains forward speed relative to the lower part, and eventually the top becomes unstable and spills, or pitches, forward.
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[quote="$1"] For sizing the waves based on the face it's best to look at it from sea level. [/quote]
True. According to a respected scientist who spent his whole life studying waves, the most accurate way to measure height with just the naked eye is as follows.
Calculate your eye level above sea level. When a wave crest is even with the horizon, the height is equal to your line of sight above sea level.
So, if you are standing four feet higher than the water line, your eyes are about nine feet above sea level. A wave that meets the horizon would be nine feet high.
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If you are talking abour Willard Bascom in 1964, you are close, but he measured the top of the breaking wave not the crest when the wave was peaking. makes a huge difference.
The top of a wave is the crest, last I recall.
Yes, I’m referring to Bascom. I’ve been through two copies of the original '64 printing (first one was bought in 1964), and now also have a copy of the second printing (1980)
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[quote="$1"] that graph is from wiki, but it is how all waves in science are measured(1)
Of course the trough is below sea level.(2) [/quote]
1 wrong
and
2 wrong.
Ocean waves adhere to the principles of other types of waves, generally. The exception being the wave form as it pertains to the medium.
A swell in open water, which is called a deep water wave, exerts equal energy above and below the surface. When a swell passes a stationary object that is floating, the object will move forward, up, and back in a near circle. Place a buoyant object that is tethered below the water's surface, and that will also move in the same circular pattern. The waves we ride are that portion of a bundle of energy moving through the water that is above the surface. It's the reason waves break. The energy under water is attenuated by the sea floor. The upper part of the wave retains forward speed relative to the lower part, and eventually the top becomes unstable and spills, or pitches, forward.
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1. how? that graph is pretty standard to measure wave length and amplitude.
2. it doesn't matter how energy makes the wave move. the fact is that to have water above sea level, water from below sea level has to be displaced. fill up your laundry sink. mark a line at the water line. make some waves. i bet the water level drops below the water line between the "waves".
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[quote="$1"] If you are talking abour Willard Bascom in 1964, you are close, but he measured the top of the breaking wave not the crest when the wave was peaking. makes a huge difference. [/quote]
The top of a wave is the crest, last I recall.
Yes, I'm referring to Bascom. I've been through two copies of the original '64 printing (first one was bought in 1964), and now also have a copy of the second printing (1980)
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PEAKING wave and BREAKING wave are totally different heights.
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Right about that Beery.
Moonee Mick & I were at G land { 96} Mackin storm surf, One guy {Camel} paddles out & catches some bombs....
As high as telegraph poles !!! We estimated 3 boardlenghts high, it turned out he was ridin a 9' 6" brewer pin. Next day I asked him how big he thought it was ? His answer..... 12ft Hawaiian. Fu@k me dead if those faces wern't 30feet high I'm a bad judge.So maybe by youre proposed scale it woulda been 5 times over head ?
Always a contentious point."
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CAMEL ....
here he is on what he may call a ' 6 foot' day , at his home break, recently .
I have not personally met the guy , but friends who have , and have surfed with him , say he is fairly ..er...'out there' [ that's is putting it mildly ! ] .... so , perhaps his judgement is er a little 'off'' , eh ??!!
I like measuring waves the moment they begin to tube but that’s just me. If there is no tube, I measure the wall excluding the through and I try to avoid using feet. I use: knee, waist, shoulder, head high, 2XOH, 3XOH etc… A lot of people here in Puerto Rico talk about 7’ or 9’ waves… hey, if you are going to use feet: 1,2,3,4,5,6,8,10,12,15,20,25,30. After 6’ use even numbers all the way to 12’ then 15’ and up in 5’ increments. I believe it is very subjective trying to tell the difference between a 9’ and a 10’ wave… By the way, if we are going to talk open ocean wave heights, which is another good way to call it, wave period is way more important…
Hey, ankle snappers is very descriptive for wave heights.
Made me think of a new scale: Ankle Snappers, Stomach Punchers, Face Slappers, Head Guillotines, Slam Your Back into the Reef r’s, Pile Drive Half your Body into the Reef r’s, Need to Remove you from the Reef with a Spatula r’s, Hold your breath for 15 Seconds r’s, Hold your Breath for 30 Seconds and Say your Pray r’s .
Note: this system is based on the aggressive nature of ankle “slappers”…
Chippy, to say Camel is “out there”, probably couldn’t be a larger understatement !!
Certainly with regards to his ability to charge in larger than “average” conditions. The guy must have balls like an elephant !!!
Hey Chip how’s it going ?
That G-Land sesh that Silverbak was talking about was maybe half as big again as those shots of Margs . HUGE barrels !!! Camel is wired up perfectly for surf like that .
It was knee high today … small but a ball.
Cheers
Mooneemick
Mr. Chip, I am curious, where is that wave Camel is riding in the photos (if it’s ok to tell) it looks big but also very hollow. Looking at the photo makes me feel like standing on a very high building and looking down, kinda get the urge to jump… Looks scary, I would be shitting my pants at half the size of that tube… “El Camello tiene cojones!”
The way I see it, there are only two wave sizes. Small enough to not even bother paddling out and then everything else.
TonyLion, if I’m reading this right, I think those pics are from Margaret River West Oz.
Thanks