Bear in mind that a mass of water moving with enough energy to form a cohesive whole won't always present as a breaking wave. It's when it collides with something it builds up into a breaker. That something can be another mass of water. Typically it's rising land to the beach or cliff. Or a contained body of water. Some of the truly huge tsunami waves were compressed by the landscape.
If you look at videos of the fukashima tsunami it's not "great wave off Kanagawa" as much as an unavoidable rising mass of water, inexorably pushing all and everything it confronts ahead of it, or subsuming it into the body.
(Not a hydrologist)
Depends on the surrounding terrain and if you are on street level. This video here has moments that if you are on street level it crashes all around 4:30 https://youtu.be/EPjliKVtmUA?si=5ELV7bnxkQBa_xZt
For example last year's Greenland Tsunami that was in a fjord reached 200m height and a top speed of 150km per hour.
Wow, I was really sad to see the number of people still running/driving up that narrow street as the waves crashed in, absolutely tragic.
> For example last year's Greenland Tsunami that was in a fjord reached 200m height and a top speed of 150km per hour.
There is no video right?
No video since nobody was around, just one abandoned station. But - the waves revertebrated in the fjords for next 9 days as its seismic impact was recorded all over the world.
Yes, Fukushima looked a lot like a flash flood compared to the kind of wave portrayed in apocalypse themed movies.
>It has often been assumed that waves are two-dimensional and understanding of wave breaking to-date has been based on these assumptions
Has it really? That seems unlikely to me. I am not even sure what the two dimensions would be, looking at the water from above or from the side?
I think what was meant were the direction of travel of the wave as one axis and the height as the second axis. The third axis would then be the direction along the length of the wavefront, as seen from above.
The assumption was that this third axis was irrelevant with respect to the wave's breaking behavior and max height - so simulating waves in a narrow channel of water would be the same as simulating waves in an ocean (as far as max height is concerned).
This paper now showed the assumption is wrong, and interactions parallel to the wave front (or coming from yet other directions) also influence the max height.
At least, that's my understanding.
from the side; the assumption is that the wave is propagating in a single direction so the two dimensions are the vertical and the axis of propagation
A great example of what waves can do when they meet each other from separate directions is watching surfers get launched when the backwash meets the oncoming wave in videos of the Wedge from Newport Beach in Orange County, California.
The article does not say what the previously thought max was and what the new height might be. Nazare in Portugal famous for its surfing conditions has waves exceeding 100 meters in height.
I think (but definitely could be wrong) that this is more about how open-water waves can form great heights (i.e. what I've often heard referred to as "rogue waves" in the past). I do know these rogue waves were a bit of a mystery in the past because mathematical modeling said waves shouldn't get that big.
Near shorelines/sea floors is a whole other ball of wax, though, because the terrain can essentially "funnel" waves into giant monstrosities like what happens at Nazare. Depending on the shape of the shoreline I don't believe there is a single "max wave" height, i.e. I believe you can have situations like the Bay of Fundy (that is tides though, not waves) where you can get massive difference in high vs. low tide due to resonance.
The fundy basin reveals many interesting hyrological phenominon,large standing waves(the dorey rippes),tidal bores(wall of water rushing inland up bays and rivers,which ((not kidding)) black ducks surf to get to the high tide and then forage all the way back out on the outgoing tide) also whirl pools form,each tide at the tip of cape split its a monsterous amount of water/mass not sure of the exact numbers,but the earths crust must flex a bit with the fundy tide then there is the permanent circum polar wave that circles antartica,100 meters plus
The Southern Ocean routinely has waves of 20-30m in size because of the uninterrupted belt of water and wind that circles the globe in those latitudes (aka the "Furious Fifties" and "Shrieking Sixties"). We obviously can't track every wave in the ocean but I think we're fairly certain there are 30m+ waves happening down there and they are not that rare.
TIL that the largest waves in recorded history were up to 500m (!!), generated by a tsunami off the coast of southern Alaska.
Even 20 meters is insane. That's 4-5 double decker buses stacked on top of each other (and probably hits with more force than they would...)
Hello, I recently read in the comment section on HN that the waves at Nazare are more like 30 meters high. Maybe you mixed up meters and feet ? Just to let you know, in case you didn't notice the other comments. Cheers, mate.
Nazare is around 28m max. Been there, and I know the world record holder.
You mixed up feet with meter.
This caught my eye. After checking it seems that the correct height is 100 feet, or ~30 meters.
Meters or feet?
The surfing records from Nazare are all under 30 meters, i.e. under 100 feet.
100 meters seems much too high for any non-tsunami wave.
The Portuguese town of Nazaré can deliver 100-foot (30.4 meters) waves.
Here's a discussion of the freak wave generation and the experimental wave pool facility where the work was done:
Bremer was in a quanta interview recently https://www.quantamagazine.org/what-causes-giant-rogue-waves...
> Wave breaking plays a pivotal role in air-sea exchange including the absorption of CO2, while also affecting the transport of particulate matter in the oceans including phytoplankton and microplastics
What impact on the climate and microplastic models does this new research have?
Irrelevant to the article/topic, but this title reminded me the phrase "Those are not Mountains. Those are Waves."
I was just thinking about this, I was at the beach so I was thinking about sneaker waves.
It sounds like the way it works is that a typical wave is a certain height, but if two waves from a wave train hit at the same time, they might be twice the normal height. But there's no reason it would only be two at time at a maximum, is there? Waves could hit from different angles and combine at the impact point (the beach), on rare occasions.
Waves are from Extremistan, using the Taleb terminology. If the maximum wave that hits a certain beach on a typical day is 10 feet, the maximum that might hit on an atypical day isn't going to be 20 feet, it's not going to be 100 feet or 1,000 feet. There's just no telling where the top of the "atypical" distribution is. The black swan wave might wipe out everything and everyone for miles around.
But that was just me thinking, not an expert on waves. The biggest ones I saw were 6 feet tops.
I've gotten into surfing over the last few years (started during covid) and it's made me really appreciate how elaborate wave patterns are.
If you know the directions of the incoming swells and you're out in the water judging each wave to decide if you can ride it, you start to get a feel for how swells that have different frequencies and are coming from different directions can merge together.
There are times when a certain combination of swell forms a great peak—maybe the long period south swell and short period southwest swell are merging—and you realize it's happening on a regular basis, like once every three or four sets. This kind of thing can actually be very useful for getting waves when it's crowded. People will tend to concentrate where the peaks are showing up most consistently, but if you can identify a "weird" peak that reoccurs on a regular basis, you can get it to yourself each time it appears even if there are like 30 other surfers nearby.
Rogue waves/sneaker waves are the same kind of thing. In surfing there's the term "cleanup set" for a set of waves that are way larger than the typical pattern and break much further out. I tend to see at least one of these per session in northern CA, though it depends on the day—while you can get cleanup sets in relatively small conditions, they seem to show up more frequently as the swell gets larger and more powerful.
And then every once in awhile there are waves that are on a whole other level. I used to play poker a lot and statistically it reminds of something like getting a straight flush. It's quite rare obviously but if you spend a lot of time playing poker you'll eventually get some. I was surfing in Linda Mar on a fairly calm shoulder high day (3-4f) and then out of nowhere I got to experience what I'm pretty sure was a double overhead wave (10-12ft) during a cleanup set. Linda Mar is a beginner spot so you can imagine the carnage that it left behind :)
How does it work from an energy point of view. If a wave weighs ten tonnes per meter width per meter high, say, each collision needs to move increasingly large amounts of water up like a hanoi tower (although some of the energy may come from vacating space going down). Is that energy coming from currents or the waves? Can you really get 100x bar a tsunami or similar?
I think the chances of three of anything colliding in a single place are extremely low
If you have 2 periodic waves of amplitude a1 and a2 coming from different directions the peaks combine at every intersection, so there's always a grid of a1 + a2 double-peaks. If the wavelengths are around 100m, there's a double-peak every 10000 m^2 (1 hectare).
If you add a 3rd periodic wave from another direction, at any point in time some of these double-peaks will align with the peak of the 3rd wave to form a triple-peak. If you set the cutoff at a1 + a2 + 0.95a3, then about 10% of the double-peaks are triple-peaks (because cos(10% * pi) ~ 0.95).
Add a 4th orthogonal wave and about 1% are at least a1 + a2 + 0.95a3 + 0.95a4. So with 4 waves, we have a quad-peak every 100 hectares (a small farm).
There are a lot of waves, and a lot of time, I wouldn't discount it ever happening.
Like he chance of someone somewhere winning a lottery.
Waves are weird and scary. Being out at sea in big waves 10m+ is some harrowing stuff. If you time your movement right you can kind of just float up stairs between levels. Keeping your meal on the table gets real hard and keeping the food down even harder. Overall would recommend atleast once. It's a hell of a life experience living out at sea, even more so when it's on a commercial boat.
Rogue waves are scary.
Not as scary as Gyp Rosetti
> The findings could have implications for how offshore structures are designed, weather forecasting and climate modeling, while also affecting our fundamental understanding of several ocean processes.
Does this translate to terrestrial and deep space signals? FWIU there's research in rogue waves applied to EM waves and DSN, too
What is the lowest power [parallel] transmission that results in such rogue wave effects, with consideration for local RF regulations?
> Professor Ton van den Bremer, a researcher from TU Delft, says the phenomenon is unprecedented, "Once a conventional wave breaks, it forms a white cap, and there is no way back. But when a wave with a high directional spreading breaks, it can keep growing."
> Three-dimensional waves occur due to waves propagating in different directions. The extreme form of this is when wave systems are "crossing," which occurs in situations where wave system meet or where winds suddenly change direction, such as during a hurricane. The more spread out the directions of these waves, the larger the resulting wave can become.
ScholarlyArticle: "Three-dimensional wave breaking" (2024) https://www.nature.com/articles/s41586-024-07886-z
Rogue wave > 21st century, Other uses of the term "rogue wave": https://en.wikipedia.org/wiki/Rogue_wave
' > See also links to Branched flow and Resonance
Branched flow: https://en.wikipedia.org/wiki/Branched_flow :
> Branched flow refers to a phenomenon in wave dynamics, that produces a tree-like pattern involving successive mostly forward scattering events by smooth obstacles deflecting traveling rays or waves. Sudden and significant momentum or wavevector changes are absent, but accumulated small changes can lead to large momentum changes. The path of a single ray is less important than the environs around a ray, which rotate, compress, and stretch around in an area preserving way.
Are vortices in Compressible and Incompressible fluids area preserving?
(Which brings us to fluid dynamics and superhydrodynamics or better i.e. superfluid quantum gravity with Bernoulli and navier-stokes, and vortices of curl, and gravity (maybe with gravitons) if the particles are massful, otherwise we call it "radiation pressure" and "solar wind" and it also causes relative displacement)
Resonance: https://en.wikipedia.org/wiki/Resonance :
> For an oscillatory dynamical system driven by a time-varying external force, resonance occurs when the frequency of the external force coincides with the natural frequency of the system.
I doubt this is relevant for EM waves. Water waves are much more complicated because the wave speed in water is highly frequency dependent. That makes things much harder to model. Whilst in optics (and thus EM) people have been reasoning in terms of wavefronts in 3d for about half a century. Look at a YouTube channel like Huygens optics to see what a former professional can easily do in his shed.
> superfluid quantum gravity with Bernoulli's and Navier-Stokes, and vortices of curl
And Gross-Pitaevskii
Surfers know this... so? Is this sort of fibbing that 3d waves are a new idea?
No, it's acknowledging that for decades, the people doing mathematical modeling of waves dismissed lived experiences and reports of waves that didn't fit their models as "anecdotal", "folklore", and "insufficiently evidenced".