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You'd want to orient the ship to hit it bow first probably, rather than on the side where it could roll or punch a hole in the ship. But what Captain in a serio
by eloff 7y ago
You'd want to orient the ship to hit it bow first probably, rather than on the side where it could roll or punch a hole in the ship. But what Captain in a serious storm is not going bow first through the waves anyway? I don't know much about the industry, so that's an honest question - maybe deadlines and route optimization still plays a role and they will often sail at an angle to the waves, I doubt they would ever sail near 90 degrees in any case, but maybe you could change a 30 degree angle to closer to 0 if you had warning.
- i_am_proteus 7y agoIt's absolutely normal to steam with little regard to wave direction in mild seas. Merchant ships typically follow great circle routes with as little deviation as possible.
- eloff 7y agoRight, but in a serious storm?
- mark-r 7y agoI think the point of a rogue wave is that it can form even when there's not a storm. They seemingly come out of nowhere.
- eloff 7y agoNot really, they're still proportional to the average wave height. So while you could always be at risk for rogue waves, the sea has to be quite rough before a large vessel need be worried about them.
- mark-r 7y agoI didn't see anything in the article that implied the rogue waves were proportional to the average. In fact the thing that makes them rogue is that they are many standard deviations away from the average.
- eloff 7y agoThis is not the first article I've read on the subject, it's my understanding that rogue waves are built from regular waves, therefore they're proportional - just many standard deviations away as you say. You can get a 20 meter wave in the midst of 10 meter waves, but you're not going to find that in 2 meter waves, rounded to an appropriate number of decimal places.
- gamblor956 7y agoThe whole point of the article is that rogue waves aren't just built from regular waves syncing together...
- wahern 7y agoDo you have a citation for that? The definition of a rogue wave is a function of existing conditions, but that doesn't exclude a rogue wave in calm conditions; it just requires a greater height in rougher seas. Intuitively I would expect rogue waves to be more likely in rougher seas, but it's another thing entirely if the physics of rogue waves requires rough seas locally. I don't disbelieve you, but an explanation of that claim would answer a ton of questions about how rogue waves form (answers missing from the Wikipedia page, which seems more inconclusive) and a page worthy of bookmarking. EDIT: Your claim seems consonant with the "linear" theory of rogue waves, but as the Quanta article explains that theory is contested by proponents of the "non-linear" theory.
- eloff 7y agoI think I see the confusion, rogue waves, by definition, are just waves much larger (twice as large, again from the definition) than the surrounding ones, sufficiently so that they're impossible under the old wave models. So you can obviously get them in any conditions. But you're not likely to get one that can sink a large container ship in otherwise calm seas (although it's not in theory impossible), which is what I was talking about if you go back to my original comment. The height is still proportional to the other waves.
- slavik81 7y agoIf the wave is big enough, bow-first won't save you. If you go over the wave, half your ship ends up cantilevered over the peak. A ship isn't built to hold half its weight in the air like that. It will break. If you go through the wave, the upper decks get hit by a wall of water. The windows blow out, the bridge is destroyed, the computers are toast and the ship is swamped.
- HenryKissinger 7y agoForce shields it is then.
- eloff 7y agoAgreed, that if the wave is big enough you're toast anyway, but bow-first still gives your best chance as I understand it. So if you had warning you'd want to get your crew into less vulnerable positions where they can evac more easily, and ensure you're facing bow-first into the waves.
- irrational 7y agoAll that is left is to go under the wave.
- gamegoblin 7y agoFWIW, this is exactly what surfers do ("duck diving").
- echelon 7y agoWhy don't we design submersible container ships? Are the energy costs of displacement while moving entirely underwater too expensive?
- learn_more 7y agoPerhaps the density of the cargo is, on average, too low. The amount of ballast needed would make it impractical.
- 7y ago
- btilly 7y agoYou'd want to orient the ship to hit it bow first probably, rather than on the side where it could roll or punch a hole in the ship. But what Captain in a serious storm is not going bow first through the waves anyway? Hitting the swell bow first will not necessarily help you. See https://www.youtube.com/watch?v=A2KqofR05TE https://www.youtube.com/watch?v=A2KqofR05TE for a video of a boat actually hit by a rogue wave. They are riding the swell correctly - but the wave hits from the side. Note that a swell and a current are known conditions that make rogue waves more likely. And it is not uncommon for rogue waves to be moving in a different direction than the swell.
- eloff 7y agoSomeone else also commented that it won't save you if the wave is big enough. I'm not contesting that. I'm just saying that gives you your best chance.
- btilly 7y agoYou ignored the point that rogue waves often move in a different direction than the swell. So orienting by the swell doesn't help you with a rogue wave.
- eloff 7y agoI'm not sure if I just missed it because I was busy, or if you edited the comment afterwards, but that's a good point. If the rogue wave comes from a different direction then orienting with the rest of the waves won't save you. In that case maybe if you could get some warning in time it could help. You might not be able to get to 90 degrees, but maybe you won't get caught flat out on the side either. Still even that may not be enough to save you. The ship that went down in the North Atlantic was hit front on and sunk.
- emmelaich 7y agoIn the sort of seas that produce rogue waves, the direction of the rogue wave is also less predictable.