wave breaking in the ocean is a three-dimensional process

[floater]

a. from the fp. looks like a significant (to me) advance in the study of so called 'freak' waves. As I understand it, it's been long a mystery that observed 'freak' waves appear both more common and larger than theory would predict. Perhaps discovery of this so called 'third dimension' is the breakthrough needed to decipher a maritime mystery.

fp: https://sailinganarchy.com/2022/06/10/axisymmetric/

To establish the differences between wave breaking in two dimensions and three dimensions, researchers used the circular wave tank at FloWave Ocean Energy Research at the University of Edinburgh to reproduce an extreme three-dimensional axisymmetric wave, the spike wave.

Results from the wave tank demonstrated that axisymmetric wave breaking behavior was very different to the wave breaking associated with traveling waves.

article:

Axisymmetric 'spike waves' far exceed limits previously thought to dictate maximum height of ocean waves

In a new study on ocean wave breaking, researchers have demonstrated that the breaking behavior of axisymmetric "spike waves" is quite different to the long-established theories on the breaking of traveling waves.

phys.org

1 minute demonstration of spike wave tank:


b. also. just thought I'd test how some of these new forum tools..

 

[Marty Gingras]

Cool. Thanks for posting that.

 

[ProaSailor]

Sailing a 35' Shuttleworth catamaran around Kauai from Hanalei to Nawiliwili Harbor (singlehanded), I once saw "pyramid waves" like this when I cut too close to land south of Anahola. Conditions were relatively mild but suddenly one of these "spikes" rose up over my head (10+ feet above the waterline!) and passed over the boat! Or the boat passed through the spike/pyramid wave... I was drenched, both companionways were open so both hulls took water below, and it was over. Another beautiful Hawaiian day. Wow, I was surprised!!

P.S. 10+ feet is a conservative estimate because I remember looking up at the wave as it passed over the boat. It might have been 14 feet as it hit the boom and main. Other than water below, there was no damage and it was a rather gentle experience.

 

[floater]

reminds me of the following. just imagine if that pyramid wave had launched directly beneath a hull.

In what seemed to be the span of seconds, the crew aboard the 57-foot Atlantic catamaran Leopard heard a freight-train-like sound, the windward hull lifted and continued to rotate-abruptly inverting everything... The cause of the capsize has been debated by meteorologists and bar-bound sailors alike. Some suggest that a volatile tornadic waterspout overwhelmed the vessel while others blame a microburst associated with an outflow boundary from the front.

Skipper Recounts Capsize 57-foot Atlantic Cat - Practical Sailor

Since 1974, Practical Sailor’s independent testing has taken the guesswork out of boat and gear buying.

www.practical-sailor.com

 

[Devoforedeckus]

A wave in the ocean, chance in a million.