Large Waves vs Rogue Waves

[w0nko]

Surf's Up

2 things: Here's a link regarding a 230' splash in Alaska (below).Went sailing week before last on the Ohio R. just downstream of Cincy, OH on my Venture 21. Had a neato experience after being passed by a dowstream bound barge (a big fast one). We were close hauled on the port tack aproximately 200 yards from the Ohio shore and surfed the barge's wake till we got close to shore. Then we tacked and surfed the reflected wake most of the way back to Kentucky. Too cool.

 

[John Nantz]

Whooo-ho-ho-hooo! ! (Jim Seamans Picture)

Those are some pictures!!! Awesome.When we get the "Oh, and I'm wanting to take up sailing so what size boat do I need to go cruising?" question we need to send them your link!Years ago I took a ship from the Antarctic up to New Zealand and we had a storm from the first day out until about a day before docking in Christchurch. That thing rolled so bad, I swear, it was on the verge of going over. You could feel the props start to come out of the water as the ship quit rolling and went the other direction. Back then a lot of people still smoked and the old cigars that spend a year or two on the ice really stank and the ship smelled of diesel fuel which was probably sloshing around in the bilge water.The galley was in operation the whole time but for serving a reduced crew - including me! And the other picture that Bob had with the "Sail R 8" boat, for the owner I have a question. So where is the front end???

 

[Franklin]

Try 500'

That's what they say will be headed toward the east coast of the US if a volcanno falls into the Atlantic off the coast of Africa as many scientist say will happen within two years.

 

[BobW]

That's not MY boat!

Just so people don't think I'm any dumber or crazier than they already do.....I pulled the picture of that little boat off the website I referenced in my post. It is called 'Father's Day' and I wouldn't sail in my bathtub in it, much less cross the Atlantic.... but the guy sitting in it actually did!The website is:www.famoussmallboats.comHere's another picture of the boat... notice, an outboard... he doesn't even have to sail into his slip!!!Franklin, I think the scenario you are describing is what happened recently on the coast of Indonesia. I guess the size of the tsunami that is caused by massive displacement of water by solid material depends on a lot of factors. I do recall, however, that in the open ocean, the tsunami was barely noticeable, no more than about 6 feet of swell.... but it was traveling at about 500 knots (?).... so you had to be paying attention!Even the video of the wave hitting shore in Thailand didn't show a very high wave. I guess that's a function of its speed and the shape of the bottom as it rises.I guess the people on the east coast will have to hope the warning system works.... of course, that won't do anything to prevent the billions of dollars of property damage from a wave that high..... could they aim it at Washington, DC, get rid of the politicians and lobbyists and we could start over???Cheers,Bobs/v X SAIL R 8

 

[JC on Bainbridge]

Got the "Heave Seas" pics

I got the reference from John's post to Jim's post. I should've looked at the previous posts more closely.Thanks guys.

 

[Franklin]

That's funny Bob

I like the comment about directing it to DC.How can anything survive a 500 mph 6' swell? I mean, it's a swell and all, but at 500 mph I would think it would have so much force and speed that boats wouldn't have time to ride up it. Thoughts? There had to be boats out there then but I've yet to hear a story of one.

 

[BobW]

It's a matter of wavelength and amplitude

and in this case the wavelength may be several hundred kilometers..... ah, heck, I'm not an expert on this stuff, so here's a quote from a scholarly source, link at the bottom of this post:"Even killer tsunami are difficult to detect as they move across the open ocean. Sensitive instruments are required because passing tsunami affect sea level by about a meter over wavelengths that are tens to hundreds of kilometers long. Could you even sense a slope in the surface at this scale? Plus, the waves of tsunami are lost like background noise in a sea of much larger wind waves. Sensors may make the pressure measurements, but the data must also be processed to sort things out."Sounds like a small boat wouldn't even notice.BTW, Cruising World March '05 has some accounts of sailors who rode out the tsunami in Phuket, Thailand, while at anchor! What a ride!!!Cheers,Bobs/v X SAIL R 8

 

[Alan]

Franklin

The mega-tsunami that will be created by the island colapse in the Canaries will be on the order of 500 meters not feet. Now we're talking about a wave the height of the Empire State Building. Eveything within 15 miles of the coast will be destroyed the entire length othe eastern seaboard. It will move across the Atlantic near the speed of sound. Where in the hell am I gonna hide!!

 

[BobW]

Glad I'm in California!

Nobody can tell what will happen, but the study quoted in the March issue of C/W mentions "... enough energy to rise as high as 165 feet when reaching shallow water...."I don't think anybody on the East Coast will really care if this happens.... it'll make the Indonesian tsunami look like stinkpot wake!And the scientists are sure it's going to happen, they just don't know when.The study says you (east coasters) will have 9 hours to get ready. So you could head for the hills... with everybody else.... or if you're near your boat, just head to sea - I don't know how far out the 100 fathom line is, but if you get there you've got a shot at riding the wave out!Cheers,Bobs/v X SAIL R 8

 

[Kevin]

Not so fast Bob!

You're not out of the woods (waves) yet! You are also in a target zone. (link) Also, in this link, evidence of a 1,600 foot wave that hit Hawaii! Makes one want to re-consider that nice home on the beach!

 

[patrick]

Ain't Skeered

About the east coast tsunami.... I live in Georgia, our depth drops off so slowly that I believe a tsunami would be no threat at all. Our depths don't break 100 feet until you're 40 miles offshore, the drop off is more like 80 miles. The thing would start to break 80 miles offshore! There is no way that is going to cause any significant damage. You must consider the fact that in Thailand the depths fall off very fast close to shore which allowed the wave's energy to reach shore. I reckon the real damage would occur from the Carolinas north and central Fl south. I wouldn't want to be in the Bahamas! Just my 2 cents

 

[BobW]

A 6,000 foot high column of water, over 100

miles long, travelling at over 500 knots....... go ahead and be confident. That wave isn't going to lose a lot of energy till it starts to dissipate on shore. Good Luck!I'm OK here, Kevin. I live 45 miles inshore, at an altitude over 1,200 feet. If I'm at the boat, I'll just head west as fast as I can.Maybe I should arrange to be able to 'borrow' one of those 'zillion-horsepower' stinkpots that will just get trashed!Cheers,Bobs/v X SAIL R 8

 

[Franklin]

The Gulf of Mexico

Sounds better and better each day

 

[BobW]

Sorry, Franklin

I moved back to paradise (Valencia, Ca) after 5 looonnnnnngggggg years in Lake Charles, LA.We went down to the beach - it was gray, with lots of tar balls that the oil companies swear they don't have anything to do with.Bubba and his buddy had backed their pickup down to where the gray water was lapping at their chrome wheels and were sitting in the back in folding lawn chairs, drinking beer and throwing the empties into the surf.....We knew we were in trouble!So I'll take my chances with the earthquakes and tsunamis..... in an hour I can be out on the REAL ocean, sailing past REAL beaches!And I never even mentioned the heat and humidity!! Or the LOVE-BUGS!!!!!Cheers,Bobs/v X SAIL R 8

 

[JohnS12875]

Gov't secret:

They didn't want to create general panic, but the truth is, skylab was brought down by a rogue wave.Really.

 

[Alan]

patrick

A tsunami wave doesn't start to grow in height UNTIL it gets to more shallow water. Yes the wave will slow down as it gets more shallow, BUT it grows dramatically in height. 45 miles inland will probably not be near enough protection from a mega-tsunami. The amount of energy that a wave of this magnitude will carry will be stagering.There was a smaller version of this in the 1600's that struck Portugal and the wave traveled hundreds of miles up rivers desimating everything in its path.

 

[Kevin]

More bad news Bob.

According to those who study and are experts on the subject, there are better beaches on the Gulf of Mexico than there are in California. Hey, to each his own, and "whatever floats your boat". BTW, I saw those two guys also, they run all around the state doing the same thing. Actually, they are trying out for a beer commercial. Wazzzzzzzzzzup!

 

[Franklin]

JohnS

You trying to make a point or just a joke?

 

[BobW]

Yeah, it's nice if you're east of the Mississippi

I think most of the grunge in the water in LA and Texas is from the river that gets shoved by the current to the west.We had to go more than 40 miles out to be able to dive in reasonably clear water.JohnS.... rogue waves must have loose lips... figure that one out?Alan, you may be right that 45 miles won't be enough.... I'm in the hills, lots of canyons, I'll be ok with a little warning...... the entire Los Angeles County will be wiped clean, though, right up and over the Hollywood sign.We can banter about it, but the Canary Island threat would pretty much wipe out the east coast (EXCEPT Washington DC, of course!) and pretty well destroy our country - the economy, at least.Old chinese proverb - May you live in interesting times.Some consider it a curse!Cheers,Bobs/v X SAIL R 8

 

[JohnS12875]

Franklin

Sorry, just being a wise@$$. It does seems the estimates of potential wave size is getting bigger and bigger as the discussion continues. Me, I'm near DC. I don't know how much power a mega wave will have by the time it rolls over the eastern shore, the bay, and the 30 miles to DC, or snakes it's way up the Potomac. At the very least there'll be some flooding like no one's ever seen. When it's all over, I may own waterfront property. (I may not have a house.) My Dad is already on the waterfront, so he'll be SOL. If we get the signal, I gonna recommend he drive straight to the airport, get in his plane and fly to Denver to visit my sister.