Ground swell vs windswell

surfed OC & AI, got my share of poundings, but made a fair share of fast, steep barrels. Stoked

 

That's awesome you got a few good ones. I am "pounding" averse, lol. I went for several big waves but never saw one that wouldn't end up drilling me or anyone foolish enough to drop in for that matter. There was a sandbar down the beach that was breaking into deeper water so it seemed to stay open longer but there was a pack of guys already on it. The last wave I went for was looking good until the last second then it jumped up like the rest and closed down for 500 feet. As I paddled back out an outside wave exploaded 25 feet beyond me so I turned around ,bear hugged my board and got the sh*t kicked out of me. When i finally came up I was 30 feet from shore and my feet were on sand so I said screw it and packed it in. Not my day for sure, but I'm glad it was somebody's.

 

Assateague? I had so much fun there today down the ORV beach. A dolphin scared the **** out of me right at sunset. Damn near bumping my board. So many great waves without a tough paddle. It gets bigger but not too much more fun.

 

I think for me, please, we should start with a definition of ground swell and wind swell.
Windswell are waves generated by the wind - right?
So what is a ground swell?
Swell generated by the ground as in the ocean bottom?

 

excellent pic Big Mike!
I was surfing those today, i mean yesterday now, on assateague too- it was a great day for assateague!
I mean wow!

 

I did the absolute most stupidest thing I've ever done yesterday too, though...i was paddling out at AI and went to duckdive, not realizing I was right over the sandbar, slammed my face straight into the sandbar in about a foot of water...not fun, but luckily I was able to shake it off...that's the first time that has ever happened to me. Can't believe with all the waves I dropped in on yesterday, I end up hurting myself on the paddle out...

 

All the waves (at least the waves we are interested in) are generated by wind.
In a given storm or wind pressure system, you will have short period wind waves generated near the center of the storm, or pressure gradient where the winds are being generated. This is what we call wind swell. As the waves move away from the stormy (strong wind) area, the wave energy becomes sorted out into groups of swells, where the high frequency waves travel faster then the lowest frequency waves. The energy of the very short period wind waves dissipate away from the center storm area due to frictional energy loss, and we are left with just the stronger, long period wave energy, which is what is often call ground swell.

The term "ground swell" is used, because as the frequency (wave period) increases the wave energy is felt deeper into the ocean depths, and can be felt all the way to the ocean bottom when approaching coastal regions.

In the surf community, the phrase "ground swell" is thrown around a little haphazardly. In oceanography text, I've never seen the term "ground swell" used, but rather "wind waves" and "swell". On Swellinfo, the terms "short period", "medium period", "long period", and "extra long period" are used.

 

It's Mitchell's photo. He deserves the credit.

 

great answer - thanks!