A question regarding swell.
 

When swell is measured for height how is it measured???
For example, a 4 foot swell. Would it be 4 ft measured from the median line? (where the water would be with zero swell)
Or is a 4 ft swell measured from the bottom of the swell up to the top of it???
Mike

I was going to guess and say it was the average water line, like your first guess. But I looked it up and I was wrong. Swell is just a word for open water wave height, and it is all measured peak to trough


Attachment 14098

How it it measured?


Seriously?




No, seriously?








C'mon man, really?













Its measured with one of these






















http://www.cepro.com/images/uploads/...pe_measure.jpg

The buoys record the data as the swells rise, so does the buoy. That being said, the buoys are usually offshore and almost all beaches take a certain swell in a certain way.

Thanks Brandon...
That explains it.
:cheers1:

Thanks Jorge for the swell reply.

Dude!

Seriously?


You're my Homie





I'm always there for my Homies:cheers1:

:D :cheers1:

Others already mentioned the right answer, but it may be worth mentioning the bouys may read 3-4ft swells but at the beach it could be a bit bigger than that. Just something I've noticed as a surfer.

Depends on where you are... Hawaiians will measure from the median to peak. So 4' Hawaiian is actually 8' here. What you're noticing is the discrepancy between swell height and wave height, which has everything to do with bathymetry and wave period. Swell is measured trough to peak. A 4' swell can easily make a 10' (face) wave if it is long period swell hitting a deep water reef. Conversely, a 4' swell with mid to short period hitting a shallow sandbar may only create a 3' face wave because the energy is dissipated by the bathymetry of the shoreline. A three foot swell at 20 second interval can make a big freaking wave if there is an underwater canyon funneling the swell, such as at the shores launch or blacks.