‘Not A Villain’ Webcomic – Page 317a

The outside water's temperature hovers around 4°C (39°F). TENka City's spheres start to cool from the outside first (obviously) so the worst place to be during a prolonged power out is near the outside windows. On the other hand, those outside windows are the only places where you can see what's going on during a power out and most of the main hallways are on the outside edge as well.

All assembly points are situated deep inside the spheres, though. It helps to conserve as much heat as possible. And the arrival of lots of bodies helps, too. And that's when they get to focus on another fast approaching problem: the depletion of oxygen in the air (or rather, too much carbon dioxide overwhelming the available oxygen).

Also, I'm traveling today, so comments may be slow in showing up.

31 Comments

… I suppose there aren’t enough working servers
for them to have one not be connected to the net.

I just love how much you’ve thought this out, the construction of the city.

4° Celsius? That’s really low. Are they drifting below Antarctic ice, by any chance?

No, that’s just the equatorial ice.

Actually, a supervolcano going off would probably produce a volcanic winter, so equatorial sea ice is not out of the question.

4 Celcius is the temp that water is at when it’s at its most densest. So deep waters tend to be 4C all the time. I’d say they’re deep, rather than north.

…north or south I meant to write. Curse you, lack of edit feature. =P

Be it Arctic, Antarctic, equatorial, or what, they are not that deep and they are definitely under ice.

http://navcomic.com/not-a-villain/page-315/

We don’t know how deep they are because there’s nothing to give scale to that image. We know that the top of the city is a bit more than the city’s diameter beneath the surface. The city could be 150 m across or it could be a kilometer and a half across.

4 Celsius isn’t even that cold.

I would say the same, but most people aren’t Canadian

With the air handling fans off turned off the air will quickly stagnate in places. If they wanted to help combat that while still retainining heat, they could slightly slope the floors or use grates that would allow the CO2 to fall, displacing O2 higher up. Course eventually the CO2 would fill the entire space unless they had some sort of plant which didn’t need light to process CO2 into O2 and planted low in the building. of course people moving around would probably stir the air around slightly as well.

Aneeka, what level does water shift to 4c and remain there? wouldn’t it be pitch dark at some point?

All plants need light to process CO2– that’s how photosynthesis works. There are chemical scrubbers that can help pull the CO2 out of the air, but those will only last so long.

“Aneeka, what level does water shift to 4c and remain there? wouldn’t it be pitch dark at some point?”

Light and temperature varies depending on location, but generally it becomes pitch black in the Bathyal zone which can start at 1000 meters (3300 feet) below the ocean’s surface.

TENka City is hovering in the Mesopelagic Zone (second level/zone in the ocean) with temperatures that can range from 20 °C (68 °F) to 4 °C (39 °F). However, due to the thick layer of ice above, the water can’t be warmed, so it tends to hover around 4 °C.

As for light, it should probably be a lot dimmer, but then readers can’t see much 😛 So, I’m claiming artistic license for the amount shown 🙂

4C is so minor that just matter of wearing a little extra clothing… Not much of a problem normally except for… humidity. Lower temp and water starts to condense and especially electrical stuff is at risk of shorting, also rust, rot, etc. become more issue. Humans exhale lots of moisture so their assembly points would also become very damp.

CO2… I assume they are using plants or synthetic equivalent to convert CO2 to oxygen because also need food, and lack of power means no grow lights for the plants.

Water is a more efficient conductor of heat than air, so 39 F water is quite chilly to the touch. Your refrigerator is at (or should be…) about the same temperature, so if you take a swig of water that has been sitting in the fridge it’s similar to the temperature outside the city.

I’ll agree 39 F isn’t ‘that’ cold for air temp, but 39 F water is about the limit of the thickest wetsuits. So now I’m curious about underwater repairs if they have access to any…

Full agreement here. I have snow melt for drinking water here…. Rivers and some lakes here are the same. Hypothermia is a real thing for people who go swimming, that water is $&%*@ cold. Air however, I don’t mind shorts in sub-zero (Fahrenheit scale) temps.

Thinking….
Heat. Air. Food. Power. Fix the last one of those and you remedy the first two… End of the day, was this city designed to survive its current predicament, or is this the titanic with one too many watertight compartments leaking?

Torrenal,

If you don’t mind me asking, where are you from? Sounds like wonderful rural living – I’m envious. 🙂

Drysuits are a must when diving in winter temperatures, so would presume that’s what they’d use for outside repairs. But even if the physical structures of the living spheres cooled down fast, the air inside would not. Air is a poor conductor of heat. So with woolly socks or something, they’d fare quite a while without heating.

To answer a couple questions people have asked:

Light: The Ocean generally gets too dark for photosynthesis at about 200 m. By the time you get to 1,000 m it’s pretty much completely pitch black.

Temperature: 4C is the average temperature of the entire ocean. In the polar oceans there’s not a whole lot of difference in temperature between the surface and the depths. In the abyssal zone, at the bottom of open ocean, water temperature is usually around -1C to 3C. In the tropics, the water temperature hits 4C typically between 2,000 m and 4,000 m.

Survival: This is really all about preparedness. 4C may not be all that cold if you’re talking about winter weather, but if you don’t have warm clothing and shelter at hand, it can kill you pretty quickly. Also keep in mind that water has a huge heat capacity – the highest of all common solids and liquids in fact. Which means that the ocean is going to act like an enormous and extremely efficient heat sink that will suck all the thermal energy out of the city very quickly.

Now given that the good folks of Tenka City have just recently gone through the end of the world, I would assume they have pretty good preparations for disaster. Assuming they have emergency shelters with warm clothing, chemical CO2 scrubbers, bottled oxygen, food and drinking water, they can probably hold out for a pretty long while without power.

Diving: The biggest problem with doing outside maintenance on the city would be pressure, not temperature. Scuba systems are limited to a few hundred meters at most, and the bottom of the city is almost certainly considerably deeper than that. I would imagine that they use ROV’s (remotely operated vehicles) for most routine maintenance and inspection purposes.

I expect any long-term under water habitat would be kept at the local pressure, give or take a couple atmospheres. This puts less strain on the structure and lets you swim in the local water. Forget to depressurize when you leave however…. And you have a few sad minutes ahead.

Which local pressure? Remember that pressure increases by a full bar every 10 meters. There’s not a good sense of scale in the picture, but Tenka City must be pretty big. The bottom is going to be at a lot higher pressure then the top. I can’t imagine making a habitat with a different pressure on each floor. You’d have to decompress every time you go up a few floors.

Some back of the envelope calculations: Let’s assume Tenka City has a population of 10,000. (I get the impression it’s actually a lot higher then that, but that seems like the minimum to call it a city.) Let’s say each person is going to need 200 cubic meters of space at a minimum: living space and mechanical space to support them. That’s a total volume of 2 million cubic meters. The illustration makes it look roughly spherical, so a sphere with that volume would have a radius of 78.16 m. So let’s round up slightly and say a total diameter of 160 m. that would mean the outside pressure at the bottom is about 16 bars higher than at the top. That’s a big pressure differential, and I’m deliberately low balling all the numbers.

Which local pressure -> Hence the ‘give or take’.

Sure, the sphere is big, i’m not arguing that. Water is dense stuff, thus pressure changes quickly with depth. No arguments there either.

But this sphere… It’s deeper than it’s big. So don’t pressurize it for the surface. Pressurize it for something near where it is.

I’d favor either all negative or all positive pressure on the sphere, so pressurize the interior to a level above the top or below the bottom. This makes the engineering problem simpler, as the sphere surface is either exposed wholly to compressive or expansive forces.

Consideration: over-pressurize, and water doesn’t leak in.
Under-pressurize, and you don’t leak air out. You don’t need to decompress to do exterior maintenance. Compressive forces are also simpler to deal with – a compressive force can more easily hold together multiple parts than a expansive force.

Assuming adequate control over leaks, exterior excursions take precedence (whether for maintenance or entertainment). Pressurize it for ten or so meters above the sphere (a true engineer might’ve able to refine where exactly to set the pressure… A diver may also have advice on depth. I’m just arm-chairing this here)

Ah, well that answers it. If it’s in the Mesopelagic, that’s just too deep to be over pressurized. Even with exotic breathing gas mixtures like heliox we can’t operate at those sorts of pressures. Of course future advancements will make deeper diving possible, but the mesopelagic is really awfully deep. At some point you’ll be running up against the fundamental limits of human physiology.

A lot of the details of the design would depend on what the engineering priorities and limitations were. And that gets back to what it was originally designed to do. Your priorities are going to be different for, say, a research station than for a commercial hub.

Actually, the thing I’m wondering is why was Tenka City built in the first place? Building an underwater habitat that big would be a huge engineering challenge. Seriously, that would probably be more difficult than building an orbital space station colony. Presumably it was built before The End, so was Tenka just showing off their engineering skills or was there a reason for it?

I would assume that it was a research station, or something of the kind, and was adapted after the End.

On the other hand, humans could have been slowly moving most of their cities to the oceans, so as to open up more farm land to tend the growing word population before the End happened, therefore TENKA City would have just been a privately owned city.
(A third-class community)

I’m new to this comic but I am enjoying what I have seen so far of it! I love the detailed world you have woven with this story and I do intend to come back and read the full archive sometime this weekend. Again, really awesome comic! 😀

Well, if Tenka City is built under a think layer of ice, that would explain to me the reason that #315 showed the city supported from above rather than anchored to the sea floor.

the detail and thought you put into your work… the art, the story, the filler info below the page… blows my mind… I truly love it all… I hope I die of old age before you decide to stop 😀

I still can’t get over the fact they seem to have no backups. No emergency lighting, no emergency power, no emergency heating by the sounds of it. I know they’re all addicted to the game, but that would make electrical power higher on their list of priorities.

They are not addicted to the game. The game serves as a distraction. Like going home and watching TV or any other mindless activity. A way to not have their situation in the foreground. I’m not sure what I would do, I gave up TV 20 years ago, instead I do stuff online of go outside. I learn, explore, and better myself. I don’t worry about second life because I have first life.

Not A Villain Webcomic

Webcomic of a semi- reformed hacker trying to redeem herself in a post- apocalyptic world she may have created.

‘Not A Villain’ Webcomic – Page 317a