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forums.bateau2.com/viewtopic.php?p=42539&sid=75dc8d001bcd9552e3fab7f328dfac92
- What do you mean "a 2.7 footer peaking can be about 5 foot high"? I assume that wave height is measured from the bottom of the preceding swell to the crest of the wave?
- That's how some surfers measure, but the correct way is from the nominal flat surface of the water to the crest. I find it easier to judge real wave height from the back than the face of the wave.
Actually, I just figure wave height by estimating the face height and cutting that in half. Although you can use subjective measures, too: a 1-foot wave looks like a 1-foot wave, a 2-foot wave looks like a 3-foot wave, and a 10-foot wave looks like a 25-foot wave.
- I'm not sure if there's a consensus on how to measure wave height. So if you say the waves are 3' high, they'll be (about) 6' from swell to crest?
- I'll be drip-dried. I've always heard sea waves described in terms of their height above mean sea level, and surfers talk about face height. After more than an hour on the web, I find credible sources using both definitions. Learn something new every day...
- After living and surfing in Hawaii in my younger days I realized wave height is measure from the backs. If the wave is a sine wave curve the measurement is from 0 (baseline) to the top, not from negative bottom to positive top.
The C19 bow is about 5 feet high, and the reported 2 to 2.7 footers were creating front faces that almost covered the bow if the speed was too high.
Surfing in hawaii on a 2-3 foot day you could ride down some 5 foot faces.
- Growing up in MN, there was little to no need to measure wave height... But coming down to south florida 6 years ago, I at first started measuring them using your criteria. Peak-to-base as electrical engineers would say.
However, EVERYONE I've talked to (off of this site) measure from the swell to the crest. So I started doing the same.
Convention is one thing. Right or wong, we should at least be consistent.
But I suppose what prompts you to measure it the way you do is how the wave interacts with you. Engineers measure RMS wave heights because that determines how much power is in the wave. Boaters and swimmers might quote peak-to-peak because that big 5' wave face is what's effecting them, and to call it a 2' wave doesn't really indicate the impact it'll have on your boat or body.
- I think the "bait shop" measurement of wave height came about so people could brag about going out in 6-footers. It doesn't sound very impressive to say that you quit fishing because the waves kicked up to 3 feet.
- we should at least be consistent. I was being consistent, .... with the buoy data and hawaiian surf shop conventions. They called it 2 foot wind wave with 0.7 swell so the larger built waves were 2.7 three seconds away from a 2 footer. I said they were stacked three footers, .... I think? Someone asked what stacked three footers was. Then someone asked how I measure waves. I promise to consistently describe wave heights the way noaa and hawaiian surf reports do, from baseline to crest, not the face height (bottom to top).
Varken mer eller mindre. Och med den linjen han som åker håller kommer han att få äta lite skit. 
