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I'm curious how the weather of the sea affects military naval operations.

How can an aircraft carrier launch and recover planes if it's being rocked by waves?

How can a destroyer launch missiles from vertical launch cells if waves are constantly crashing on the deck?

I wonder how a Navy made up entirely of nuclear submarines would fare against a more diverse force with an equal number of hulls.

Submarines won't do the coastal bombardment and air strikes and escort and reconnaissance work that regular navies are capable of.
Well they do some of that: reconnaissance both electronic and visual, coastal bombardment (and air strikes) with cruise missiles, and they can land very small groups of special forces too. Not to the extent surface ships can but if suddenly something made surface warfare impossible, submarines could take over a chunk of it. And you can imagine easily how drones might be embarked on a submarine and launched like cruise missiles.
> coastal bombardment (and air strikes) with cruise missiles

Submarine-launched missiles, in a diverse navy, can launch from underwater. That's great for stealth. It's terrible for budget. A submarine-only fleet would need to surface to economically attempt coastal bombardment and air defence.

That said, I'm not sure what fraction of e.g. the U.S. Navy's submarine missiles are capable of subsurface dispatchment.

Aircraft carriers are gigantic and are designed to be stable. I’ve never been on the largest ones, but as a Marine I was on the Essex (a smaller carrier for jump jets and helicopters) and we sailed basically directly through a typhoon. The ship was pretty stable, pitching about 10 degrees from side to side. Enough to make some experienced sailors toss their lunch, and even if there was no wind, I think it would have been very treacherous to do flight ops with the deck pitching like that.

For fixed wing jets that need to land on deck… even if you ignored the wind that goes along with these conditions, I think recovering aircraft would be too great a risk. That does bring up the wind and visibility that (almost always) goes along with these extreme sea states, which would be probably just as hazardous as the deck pitching about to flight ops.

For basically everything else, I think the naval systems work just fine in bad weather.

In regards to rogue waves, an 85 foot wave would put green water on the flight deck of the carrier I was on, something that would be difficult to imagine for me. Aircraft on the flight deck are chained down with multiple chains, each of the chains having the strength to hold the entire aircraft down, so I can’t imagine losing aircraft, but flooding the planes with sea water probably wouldn’t be good for them.

> Aircraft carriers are gigantic and are designed to be stable

The ocean is bigger.

It is only a matter of time until one is lost

The ocean is the boss of sailors, a loving but harsh mistress.

There have been plenty of aircraft carriers sunk, not sure what your point is.
https://en.wikipedia.org/wiki/Typhoon_Cobra

3 destroyers sank, with almost 1000 lives lost, and virtually every ship in the fleet took enough damage to at least force a port visit, if not a major repair/refit.

Not positive how this got misconstrued, but I'm not saying an aircraft carrier is unsinkable. I'm saying it's designed not to pitch and roll as much as a say a destroyer or frigate. That's it.
There were carriers in the Typhoon rolling 70 degrees.

Virtually every aircraft in the fleet either tossed into the sea or damaged beyond even wartime economic repair

I'm curious how such a wave could be....intentionally created.
That's actually a minor plot point in Neal Stephenson's latest novel "Termination Shock."
There were attempts to create tsunamis with nukes. But I’m not sure how effective this sort of thing would be against a carrier. A single wave could I guess be spotted from pretty far away, and is just a problem for a plane that wants to land or takeoff at that very moment. Creating general chop in excess of what the carrier can handle might be annoying, but it seems much more difficult (lots of energy involved in creating a bunch of waves, and I guess this rules out using a single huge explosion).

Plus, I bet somebody would work out who did it if a country used a nuke to create a wave, there are only a couple candidates for who could do this sort of thing, after all. I bet it would have pretty significant diplomatic ramifications to… inconvenience a carrier group for a couple minutes.

> There were attempts to create tsunamis with nukes. But I’m not sure how effective this sort of thing would be against a carrier.

Not very effective.

Tsunami waves move huge volumes of water, but in the open ocean they are also very long waves. Their travel speed is about the same as the "linear long wave speed", or about sqrt(g*D) where D is the depth of the water.

As these waves approach the shore, however, the ocean becomes more shallow. Waves slow down. The tsunami effectively "piles up" on itself, and a wave that was a little high and a lot long becomes a wave that's a lot high and a little long.

A carrier operating away from shore would see the tsunami in its more benign state. Coastal cities, however, would be in trouble.

There was an experimental, and secret, programme in WWII to attempt to generate tsunami as weapons In New Zealand

I know very little more than that, but it was in the news here some years ago.

I do know it was a failure, quite a comprehensive failure

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Are rogue waves just the various component waves on different frequencies lining up "perfectly" such that they sum to one large wave? Or are they a different phenomena?
No one really knows what causes them - plenty of theories but not facts - and that's why they are both exceptionally facinating as to how they form, and yet also utterly terrifying.
I have a theory that there is something down there, deep in the uncharted depths of the oceans lurking and causing rogue waves, but its just a theory one I dearly hope is wrong...
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Even worse, it's standing in our night sky, in periodic plain sight, taunting us with it's waxing and waning, knowing there's nothing we can do to stop it.
Cold-hearted orb that rules the night...
In partnership with the murder-ball of burning hate that bakes the day.
Now imagine how scary the rogue holes are, the inverse of rogue waves.
”[T]hree years past, there happened to me an event such as never happened to mortal man -- or at least such as no man ever survived to tell of -- and the six hours of deadly terror which I then endured have broken me up body and soul.”

A Descent Into The Maelstrom, Edgar Allan Poe, 1845

https://poestories.com/read/descent

I may have experienced a very small one, 10-15 years ago - and I still have flashbacks.

Was a crew member in a sailing regatta and for one 5-10 minute period the waves were just coming from everywhere, breaking all over the place. It was exhilarating, like riding a roller coaster up and down! Then a (relatively) very big one, out of the blue. It seemed to go between us and the next boat, maybe 60 feet away. From the deck, we couldn't even see the top of the mast of the other boat.

And then we fell out of the water.

Our boat, all 30,000 pounds of it, dropped straight down and we crashed, hard, into the water below. The mast bent so much that the cable stays were loose. The impact threw everyone down. The sound: it sounded like the fiberglass crunched and broke. For a moment we all thought we were dead. But we weren't. The mast snapped back so hard the cable stays made a twanging sound. Sails limp - no wind at the bottom of the hole. Then the water all around us swallowed us up; our buoyancy sent us shooting straight up with a lot of force. The wind hit us hard; no time to reflect; have to deal with that now.

Oof. That would make a landlubber out of me.
All those years of racing, including being in multiple collisions, taught me that it is surprisingly difficult to sink a boat. As long as you can maintain hull and deck integrity, you need a LOT of water inflow in a very short amount of time to eliminate buoyancy.

We were never a good team, but I came away from it with far more confidence being on the water than I started :)

"Always step up into the lifeboat."

This is advice, hard won, by mariners who abandoned their ship, were lost at sea in their lifeboat, and left behind them a ghost boat that eventually makes its way to shore.

only kind of, the suprising thing is they are way bigger than expected (or rather, rogue waves of a given height are orders of magnitude more likely than you would expect from just adding together the statistics of each frequency of wave). There's some other interaction or non-linear behaviour going on which causes them to occur with the frequency that they do, and I don't think there's a single model which actually explains them.
Wave dynamics, specifically ones which have interactions with the ground, are some of the few systems that need derivatives higher than two to describe them. Lots of interesting stuff going on
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They're quite rare, but my understanding is that they can come from an angle different from the prevailing winds / waves, so it's something else.
If you are interested in this topic, I recommend _The Wave_ by Susan Casey. She covers both rogue waves and big wave surfers.
I thought this book was decent, and I don't know of any others better in the niche, but I wanted a bit more science than was presented. I think Casey got too intimidated by the scientists to really try to understand the models at all, and then spent too much time fawning over Laird Hamilton. But perhaps that was a decision made by the editors rather than by Casey navigating two very different groups of protagonists.
Yeah, it was definitely not what I was expecting in terms of balance between the science and the surfing personalities. My impression was that she really lacked enough hard science material (that was sufficiently interesting given the audience). I will admit that in the end I was way more interested in the big wave surfing, a topic I really didn't appreciate before.
I don't understand this article. It says at the beginning:

```

In November of 2020, a freak wave came out of the blue, lifting a lonesome buoy off the coast of British Columbia 17.6 meters high (58 feet).

The four-story wall of water was finally confirmed in February 2022 as the most extreme rogue wave ever recorded.

```

However, right below that, it says:

```

It wasn't until 1995 that myth became fact. On the first day of the new year, a nearly 26-meter-high wave (85 feet) suddenly struck an oil-drilling platform roughly 160 kilometers (100 miles) off the coast of Norway.

```

New wave is 58 feet, wave in 1995 is 85 feet?

It is indeed unclear.

The resolution is that the absolute rogue-wave-height isn't the measure of extreme, it's the rogue-wave-height relative to the typical height. This is explained in TFA if you read carefully.

> Scientists define a rogue wave as any wave more than twice the height of the waves surrounding it. The Draupner wave, for instance, was 25.6 meters tall, while its neighbors were only 12 meters tall.

And of course this makes sense.

as the article says, it's "most extreme" with respect to its size compared to the surrounding waves: "the Ucluelet wave was nearly three times the size of its peers."
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> the one that surfaced near Ucluelet, Vancouver Island was not the tallest, its relative size compared to the waves around it was unprecedented.

>Scientists define a rogue wave as any wave more than twice the height of the waves surrounding it. The Draupner wave, for instance, was 25.6 meters tall, while its neighbors were only 12 meters tall.

The one in Norway was only roughly double the height of surrounding waves.

>> Scientists define a rogue wave as any wave more than twice the height of the waves surrounding it.

Right, so they have to be much more common than said, because a rogue wave could be 6" high on glass-calm seas.

'Extreme' is probably relative to the other waves in the area. Like doritos extreme.
Basically a five foot wave surrounded by one foot waves would be most extremist extremely rogue wave ever.
I'm surprised someone tried to estimate that this is one-in-1300 years event when we don't know how they form, have no data on them, don't know much about those waves.
> we don't know how they form, have no data on them, don't know much about those waves

We know a surprising amount about their mechanics due to replication in the lab [1][2]. We don't have lots of observational evidence to support the lab effects accurately replicating the ocean, but I don't think we've generally seen evidence for lab surface water materially differing from ocean surface water.

[1] https://en.wikipedia.org/wiki/Rogue_wave

[2] https://openresearch-repository.anu.edu.au/bitstream/1885/70...

If you start measuring something (wave height) and detect a high value in, say, the first year, you better have a very good reason the think the event happens every 1000 years. Especially if you are measuring a few points in a very large ocean.
Right. The "once in X years" reporting is always exaggerated, by subtly constraining it to a specific geographical point.

If there are 500 measuring stations, then every year some one of them is going to experience a once-in-500-years event. We just never notice the other 499, and cherry-pick the one outlier after it already happened. (Yeah, there can be correlation between station measurements; obviously I'm speaking in generalities.)

> Right. The "once in X years" reporting is always exaggerated, by subtly constraining it to a specific geographical point.

Not really. You got it exactly backwards. The return period of an event is determined based on all recorded events. This does not mean that massive events that took place in the past didn't existed if no record was kept. Consequently, massive events are underrepresented both in magnitude and in frequency, and consequently estimates of their return period tend to be larger.

Think of it this way: the concept of the return period of an event (i.e., this is a one in X year's event) is determined based on the average time between similar events.

I think what that is, is the probability prediction you get from the naive model, known to underestimate the probability of very large waves.
Indeed!

The buoy was in for at most a handful of years, and catches a 1-in-1300 year event in that one location?

The first thought on that should not be "what incredible luck!", but "is there something special about this location, or is that 1-in-1300 estimate off?".

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The nomenclature of 1 in x years is based on statistics and equates to the chance, 1/x, that in a given year this event will happen. You don't need 1300 years of data to say this was a 1 in 1300 year event, but you can say that this event had a 1/1300=7.6^-4 chance of happening in a given year. And that can be calculated based on any amount of data. Of course, more data will give a higher confidence to the statement.
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Such an exceptional event is thought to occur only once every 1,300 years.

Do they mean per-buoy? Or what?

They have no idea and are making up numbers
-- having trouble picturing this - from a distance it look like a massive wall of water floating along on its own? - waves go up and down so why doesnt the masive wave going down change the amplitude of the waves in advance of it? - so confusing try to picture - the animation in the article didn't help --
Dunno but you know how you can do a single big wave on a long skipping rope traveling down the rope? You like whiplash it.
Short, non-technical answer: These waves are actually the "sum" of a number of different waves (of different frequency and/or phases). It can happen that many of these _usually_ cancel each other out in the sum, but once in a blue moon, their peaks happen at virtually the same time. Then you get one massive pulse. The moments right before and after could look quite normal.
Not sure if this is what you mean but there's a documentary out there called 100 Foot Wave that has tons of video footage of gigantic waves. It's about surfing, so these waves break, but it's worth a watch if you'd like to see these things in action. The images of the waves are awe inspiring, even on a TV screen.
In the video they show the full animation with the surrounding wave context and it makes it a little easier to understand than the gif.

The first massive wave lumbers through at the same pace of the surrounding waves leaving you thinking "Oh that big wave is the rogue wave" when suddenly the bottom drops out and an even more massive wave comes very fast and seemingly overtakes the slower one. It seems like the slower large wave just stops in place and reduces in amplitude while the rogue wave overtakes it.

I'm really excited about seeing this on HN - the CEO of MarineLabs was my roommate in university!
My buddies and I aspire to sail around Vancouver Island, but it's stuff like this that scares me.
In the open ocean these are terrifying and why you must always be vigilant. But it is close to land where they are deadly

The bottom may be exposed by the trough

They may crest breaking over your boat smashing it

In confined waters maintaining heading may not be possible, which is critical

I'd probably be more wary of logs in the water than freak waves
I sail in the area and would be more worried about shipping traffic and submerged/lost trees or shipping containers. Hope you all get to make the trip someday, on my list as well
Oof, we have already bonked into enough lumber in poor visibility. Hoping that if we keep X miles offshore there's fewer logs.

I've been petitioning for a bow- or mast-mounted camera for spotting debris.

For those interested in this topic, The Wave by Susan Casey https://susancasey.com/books-list/the-wave is an entertaining read, alternating between accounts of surfers following the waves and history of various waves. Some science of various resonances and chaotic systems is discussed but all too briefly.

The most interesting part of her documentary book for me was the fairly recent event of 1740 foot/~550 meter tall tsunami wave that generated by a mountain breaking and falling into the sea as result of serious earthquake in Alaska, and 1 (one) person who survived riding on it in his boat. Truly an epic wall of wate that was measured for us by the high watermark of the broken trees on the surrounding mountains.

> the fairly recent event of 1740 foot/~550 meter tall tsunami wave

This isn't exactly true. The ~550 meter height corresponds to the height up to which trees were cleared. However, the tsunami was created by a massive landslide in a contained bay, which pushed the water uphill much like someone falling in a filled tub can push water up the walls.

A rogue wave captured on film was in the second season of The Deadliest Catch: https://www.youtube.com/watch?v=A2KqofR05TE
Dunno if the narrator is just hamming it up for the audience but what he says completely contradicts the article:

> The four-story wall of water was finally confirmed in February 2022 as the most extreme rogue wave ever recorded.

Video says it was a 5-story wave.. "60 feet", article's wave was 58 feet.

The one confirmed in 2022 wasn’t the biggest ever recorded in overall height, but the biggest compared to the other “regular” waves occurring around it.
I'm sorry but this reeks of made up bullshit for TV on a show that would be notoriously boring if not for invented drama. I'm sure they took a wave but I don't see any evidence that it was a rogue wave.
There aren’t just rogue waves, there are rogue holes too. Imagine being in a boat and it just drops a 50ft.