is the conventional wave height measurement used by surfers
, also used in Australia
and parts of South Africa
The measurement is always in feet and scaled so the actual height on the face is roughly twice what's quoted. So a 3-foot wave would be head high (to a 6-foot person), or 2-foot around chest high. 6 to 8 foot would be 2 to approaching 3 times head high. Large waves are difficult to judge though, and the measurement becomes a little fuzzy towards 20 feet.
The origin of the scale is obscure. The candidates are:
[*]Hawaiian life guards calling smaller sizes to keep tourists away.[/list]
[*]The measurement is "from the back" of the wave, or from wave buoy readings.[/list]
[*]Macho understatement by early surfers.[/list]
In Australia, which is otherwise metric, feet are still used by surfers and surf-specific media (e.g. ASL and Tracks magazines). Some of the non-surfing media make an attempt at metrication by direct conversion (e.g.), so 3 feet becomes 1 metre. In a sense that satisfies neither surfers who don't use those units, nor non-surfers don't know it means twice that on the face.
[*]Hawaiian Scale: Measuring Wave Heights in Hawaii by Neal Miyake, 2003"[/list]
An old Hawaiian Fisherman, Marcus Rosehill, told me when I was young, that the measuring of waves from the back was a practice of ancient canoe voyagers.
They time spent in the open ocean and approaching the shore was the easist time to understand the size of the swell,
My statement was meant to clarify, not to cause turmoil.
Aloha from Oregon!