2829: Iceberg Efficiency

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Iceberg Efficiency
Our experimental aerogel iceberg with helium pockets manages true 100% efficiency, barely touching the water, and it can even lift off of the surface and fly to more efficiently pursue fleeing hubristic liners.
Title text: Our experimental aerogel iceberg with helium pockets manages true 100% efficiency, barely touching the water, and it can even lift off of the surface and fly to more efficiently pursue fleeing hubristic liners.


Ambox notice.png This explanation may be incomplete or incorrect: Created by A 90% EFFICIENT ICEBERG. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

This comic humorously plays with the idea of efficiency in a typically absurd and satirical "Black Hat" fashion. Black Hat starts by critiquing traditional icebergs, which are mostly hidden underwater, as inefficient. Efficiency is typically measured in relation to a desired outcome or purpose; Black Hat seems to imply that the obvious purpose for icebergs is to be seen above the water. He then presents his solution - a foam-filled iceberg that floats almost entirely above the water, claiming it to be highly efficient.

Black Hat's idea is absurd. Icebergs are naturally formed structures, with no particular purpose in existing. It is possible to imagine edge cases where a "more efficient" iceberg would be desirable, such as if the goal were to increase the overall albedo of the planet (perhaps to mitigate climate change), but on the whole his proposal to create a "foam-filled iceberg" is not only impractical but also comically exaggerated.

Black Hat then absurdly suggests that his lightweight iceberg can still pose a threat to ocean liners (as if that's the "purpose" of icebergs – in the 20th century, at least six ships sank directly as a result of iceberg collisions, famously the Titanic) through the use of torpedoes. In addition, given that Black Hat is promoting the idea that icebergs should be able to damage ships, it's not really so inefficient to have much of the iceberg underwater, since ocean liners also have a significant portion of their hulls underwater, which can be damaged by an iceberg. The second panel shows that the foam-filled iceberg has a small attachment underneath it, which is apparently a turret for launching torpedoes.

The unnamed individuals in the last panel are clearly baffled and concerned.

The title text introduces the concept of an "experimental aerogel iceberg with helium pockets." Aerogels are a class of solid, porous materials known for their extremely low density (making them among the lightest solid materials yet synthesized). Their low density should make them float well in liquids, though their low mass and their porous and brittle material properties make them unsuitable as a ramming implement. They are very strong for their mass, but would not be able to support iceberg-sized amounts without collapsing without internal supports which would vastly outweigh the aerogel. Most aerogels cannot float in water without some kind of surrounding coating or container, since the water would soak into the aerogel as it does a sponge. Worse, most aerogels are very hygroscopic, and contact with liquid water can destroy them because attraction to the water collapses the structure. (This can be prevented by treating the aerogel with a hydrophobic material that coats the aerogel particles.) The structure of an aerogel surrounds pockets of air, leaving spaces that could be infused with a specific gas such as Helium. Helium is lighter than air, and is often used to make gas-filled objects such as balloons float. An aerogel iceberg infused with helium gas could theoretically hover or fly like a balloon as suggested in the comic. This idea of producing a man-made flying iceberg for the sole purpose of endangering cruise liners, would likely be seen as preposterous, as more practical or direct methods of attacking such vessels exist[citation needed], thereby adding an extra layer of exaggerative humor to the comic.

The mention of this high-tech iceberg being able to "more efficiently pursue fleeing hubristic liners" is a playful nod to the comic's theme of optimizing icebergs for efficiency. It implies that not only can this special iceberg float efficiently, but it's also equipped to chase after and "efficiently pursue" arrogant or prideful ocean liners, turning the concept of iceberg efficiency into a surreal scenario. The "hubris" alludes to the (possibly apocryphal) quote "God himself couldn't sink this ship," and similar sentiments expressed in reference to the ocean liner Titanic, which struck an iceberg and sank with many casualties.


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Black Hat is holding a stick and standing next to an image of an iceberg halfway submerged in water, presenting to an unseen audience.]
Black Hat: A standard iceberg is only 10% efficient.
Black Hat: 90% of the ice is hidden underwater, totally wasted.
[Black Hat is now standing next to an image of the same iceberg, with another "iceberg" almost entirely above the surface of the water to the right of it.]
Black Hat: Our next-generation foam-filled iceberg achieves near-100% efficiency, floating almost entirely above the ocean surface.
[Black Hat is still holding a stick, but is standing next to nothing. There are no other people directly shown, but three distinct 'off-frame' voices are indicated.]
Black Hat: "But wait," you might be thinking. "How will such a lightweight iceberg pose a threat to hubristic ocean liners?"
Black Hat: That's where the torpedoes come in.
Off-panel voice 1: I'm sorry, what project are you part of, again?
Off-panel voice 2: I assumed he was with you.
Off-panel voice 3: Security?

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BH clearly isn't Freudian. For the Iceberg of the Mind, the most important part is the 90% of it that is hidden. Which makes for a totally different (and potentially more implementable) solution whenever you happen to consider that the most important function of an iceberg is to sneak up on ships... ;) 13:26, 15 September 2023 (UTC)

i added a transcript hopefully it isn't horrible Me[citation needed] 13:47, 15 September 2023 (UTC)

Tweaked (slightly, to personal descriptive tastes), but definitely not horrible. 14:07, 15 September 2023 (UTC)

Does anyone have knowledge of aerogels being infused with helium? I'm assuming it wouldn't be too outlandish to do so, but honestly don't have a lot of experience with them. Fifteen12 (talk) 14:39, 15 September 2023 (UTC)

It'd be complex. Most are 'open cell', so need an external coating. Or "pockets of helium" could mean small helium-filled ballonettes embedded within aerogel; being uniformly externally supported by the aerogel, these pockets could be structurally less bulky than traditional bladders of lift-gas (still need to be impermeable, but without the inflate-stretching of rubber, can be a more 'delicate but efficient' material, perhaps graphene). You could (also?) coat the outside of the aerogel, but adding an arbitrarily large envelope of such a membrane around helium-infused aerogel and then adding more (normally aerated) aerogel onto the outside as additional buffer/structural precaution might be wise(r), as you go ship-hunting... 15:22, 15 September 2023 (UTC)

It seems ChatGPT was use to write the description text? The contributor share in on XKCD's euphoria channel: https://chat.openai.com/share/02006f2e-cca5-4518-8fb4-f9176b39512e 16:04, 15 September 2023 (UTC)

What aerogel would break down in water? From what I've seen, I thought most aerogel was made of silica? (There's actually no gel left in an aerogel; the gel is replaced by gases.) Is this an error produced by ChatGPT? Since my searches just now have turned up no mention of aerogel being made water soluble, I'm removing that statement for now; if someone has a citation supporting it, we could add it back in? ProphetZarquon (talk) 20:28, 15 September 2023 (UTC)

Wikipedia has a section on waterproofing aerogels which talks about "hyrodoxyl groups...causing [the aerogel] to catastrophically dissolve in the water". However, the source it cites clarifies that this is only for aerogels made with a certain process. Other aerogels can be easily made that invert the hydrodoxyl groups and prevent structural breakdown, resulting in hydrophobic aerogels. I presume Black Hat would be smart enough to get his chemistry right. I agree with removing that part.Fifteen12 (talk) 01:20, 16 September 2023 (UTC)
Silica is so hydrophilic that when a drop of water contacts a silica aerogel, the aerogel rips itself apart to soak into the water. Or so I have read about the early research on aerogels. It's why the gel has to be dried by supercritical extraction rather than just by evaporation/heating. BunsenH (talk) 19:43, 16 September 2023 (UTC)
Unsurprisingly, the information I learned back when aerogels were newly discovered is out of date. But it appears that good-quality silica aerogel, and pieces of any significant size, still require supercritical drying. BunsenH (talk) 19:50, 16 September 2023 (UTC)
Neato! I'd never heard about that in any of my reading on the subject! What about the explanation saying that (non-soluble) aerogels would admit water like a sponge? That sounds incorrect, as they wouldn't have good insulative properties if the cells weren't closed off from each other. I'm pretty sure any aerogel that doesn't dissolve, would float, exceptionally well?
ProphetZarquon (talk) 02:04, 17 September 2023 (UTC)
The structure of silica aerogels is a network of "strands" composed of tiny silica nodules. It's entirely open. They're good thermal insulators because the network disrupts convection and somewhat inhibits other gas movement. Back when aerogels were novel, when I was in grad school doing organometallic chem, we had a weekly presentation by one or two of us -- brainstorming our research + getting practise in presenting. I did one such talk about aerogels, mostly because they were Really Cool, but I tied it in to our own work by noting their potential for catalysis. The nifty thing about aerogels in that regard is that they're almost entirely "surface area": almost every atom/molecule is close to direct contact with the void volume. That makes for efficient use of a solid catalyst, which are often expensive... either making aerogel directly from them, or bonded to something like silica. BunsenH (talk) 04:15, 17 September 2023 (UTC)
Indeed, now that I look specifically for aerogel + water, I see that they're extremely useful for their selectivity as a filter material, with hydrophilic & hydrophobic variants being just the tip of the iceberg (so to speak). ([1]) I'm amazed that a material that's almost entirely hollow, can also be open-celled & yet still obstruct gas flow enough for an inch of it to stop an acetylene torch cold (so to speak!)! The only closed-cell aerogels I find reference to, use plastics to seal them up; the aerogels are just a lattice... This is directly at odds with my initial impression of aerogels as basically being a hard-set silica or carbon foam. Once set, it really is structurally more like a sponge than a foam? Thanks for the enlightenment; this info has led me to a bunch of fascinating reading on a subject I thought I'd grown bored of hearing about!
ProphetZarquon (talk) 22:25, 17 September 2023 (UTC)
Thank you for that link; that's going to make for some interesting reading. There's a lot more to the field than I could have imagined. Without having gone to the source papers yet, I can make guesses about some of the chemistry: "if I wanted to use aerogels to selectively capture heavy metals, I'd do it with sulfide groups". I'll see how my guesses pan out. :-) I admit to some skepticism about trying to do some of the extractions on a large scale rather than a bench scale. Trying to do environmental remediation, as implied, would require large amounts of expensive and somewhat fragile gel material.
EDIT: As far as I'm aware (and again, I'm way out of date), aerogels pretty much have to have an open structure in order for the escape of the solvent/gases that are evolved/used in their manufacture. BunsenH (talk) 16:06, 18 September 2023 (UTC)

Why not filling the aerogel with hydrogen? You might save for torpedoes then. -- Hkmaly (talk) 21:24, 15 September 2023 (UTC)

"God himself couldn't sink this ship." That's just giving Murphy a temptation far too great to resist. Naval architect Thomas Andrews, the leader of the Titanic's design team, knew exactly how much damage his ship could sustain and stay afloat, and he knew that the damage inflicted by the iceberg was too great to sustain. He did not survive the sinking. 22:12, 15 September 2023 (UTC)

Wouldn't helium be a better choice for the low-mass pursuit iceberg? Not only is hydrogen even lighter than helium, it can combust when exposed to heat and oxygen, making the limited kinetic energy of a collision less relevant. GreatWyrmGold (talk) 14:28, 16 September 2023 (UTC)

Assume you meant "Wouldn't hydrogen be a better choice...", from context/rest of your argument. In which case, pperhaps a floating(-in-air!) iceberg that attacks just the one ship is considered less efficient than one which can (potentially) attack several..? 15:31, 16 September 2023 (UTC)
An hydrogen-filled "airberg" would also be easier to dispatch by firing at it remotely, igniting the hydrogen. An helium one wouldn't have that weakness. Black Hat would have anticipated this. Ralfoide (talk) 17:19, 16 September 2023 (UTC)

Since an _iceberg_ is made of ice, how would be called an helium-filled one? "hellberg"? I posit that the generic term would be an "airberg". Ralfoide (talk) 17:19, 16 September 2023 (UTC)

I did some calculations, based on the data that, at 0 degrees C and sea level, a cubic meter of either hydrogen or helium will lift 1 kilogramme (close enough) of mass, and the average Iceberg Alley iceberg has a mass of 100,000 tonnes. I worked out that, to lift that "average iceberg", one would need a cube of lifting gas 500 m (five average USA city blocks) per side. If this is correct, the challenge of fitting that cube of gas inside the average iceberg is (ahem) nontrivial. 17:45, 16 September 2023 (UTC)

How about if you used liquid helium, the same lift in a smaller volume? (/jk!) 18:49, 16 September 2023 (UTC)

The 'Lusitania' was sank by torpedoes fired from underwater.

"This idea of producing a man-made flying iceberg for the sole purpose of endangering cruise liners, would likely be seen as preposterous". In fact, that would be an perfect plot for an upcoming 'James Bond' film, as an high percentage of the Villain's plots in the franchise are considered preposterous: Every Bond Villain Plan, Ranked by Insanity These Are Not The Comments You Are Looking For (talk) 18:53, 17 September 2023 (UTC)

Disappointed that that link doesn't bother to include the other Casino Royale (with David Niven, although the rather sane/'sorta-faithful' Barry Nelson version predated even that), which has in-universe insanity in spades (never mind actual production-insanity!), including an actual flying 'UFO' (used for kidnapping, not for torpedoing). 21:15, 17 September 2023 (UTC)

i'm removing the incomplete tag on the transcript since nobody's touched it for 4 days Me[citation needed] 23:18, 19 September 2023 (UTC)