Climate thread for bizarre cases and pedantics

Substantial postings about constructed languages and constructed worlds in general. Good place to mention your own or evaluate someone else's. Put quick questions in C&C Quickies instead.
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Climate thread for bizarre cases and pedantics

Post by mèþru »

A lot of people seem to have questions on how to make a realistic planet. The problem is that the guides that they are directed to don’t clarify everything. Some details are not touched on, and some just assume that the person knows how to adjust astronomy equations for situations unexplained in the guide. This topic is for those who have trouble with the astronomy and climate making parts of conworlding and need help that can’t be found on the Climate Cookbook or the PCK. This is for questions of pedantic precision and astronomic equations, both simple and complex.

Click SHOW to see my own question (Warning! Very long!):
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I have looked for guides on making climates and filling details about a planet, but all of them assume a planet with modern day Earth features. How can I figure out the workings of an alien planet?
Note: This is made by a bungling amateur with no clue about how any of this works. If something looks like total nonsense, kindly explain why it is impossible.
Some major differences from Earth:
  • Two natural satellites
  • The orbital period is 0.22 Julian years
  • The planet has about a mean radius of ~0.85⊕ and a surface area of ~0.72⊕
  • Sidereal rotation: 18h 12m 16s
  • The sun is an orange subgiant or subdwarf (I forgot which, but it is one of the sub-suns)
  • Equatorial rotation velocity: ~1,862 km/h
  • Axial tilt: 12° 13’ 12”
  • Surface temperatures range from -70.6°C – 77.3°C. These are the coldest to hottest temperatures on the entire planet, not average temperatures.
  • Atmospheric pressure: 0.7 atm
  • Atmospheric composition:
    40–48 Nitrogen (average 44.8%)
    20~39% Oxygen (usually ~34.52)
    10–13.35% Carbon dioxide (usually ~10.35)
    0.00012–~7% Water vapour (climatic variation)
    ~1% Methane (depends on amount of large animals)
    0.000039% Argon
    0.00392–12% Other
  • More than 70% of land is on a single, fat, vertical “belt” of land.
  • The amount of water in the oceans is only 45%, an outstanding number compared to 96% of our water. Also, only 50% of the world’s water has salt in it, and much of the salt water not from the ocean is so brackish that it is almost fresh. 24% of the world’s water appears in surface lakes and rivers, and the rest is underground. This does not count ice as water. The oceans are way less deep than ours, and could be alternatively be considered very large seas.
I have seen two main methods of making climates: one uses tropics and poles defined by axial tilt and the other uses cells, whose number is determined by equatorial rotation velocity and size is determined by the distance warm winds can travel in the conditions of each cell (as I don’t know the equations, I just assumed a Hadley, Ferrel, and Polar cell, with the Hadley at 31.5°). Which one is responsible for climates in real life? If the answer is both, is there a way to combine the methods?
Finally, are there a way of determining tidal patterns for different moon systems and climates in the ocean? As one of the inhabitants is an intelligent amphibious creature that live mainly under the ocean, I need a complex way to determine how they live in different ocean locations.
I’m not asking for anyone to make my planet description. All I want is equations, and then I can plug what I want for all the variables and fix everything wrong on my own.
I don’t have a map yet because my drawing skills (both virtual and real life) are nonexistant. When I finish learning how to use GIMP, I will post a climate map.

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Re: Climate thread for bizarre cases and pedantics

Post by Salmoneus »

mèþru wrote:
  • Surface temperatures range from -70.6°C – 77.3°C. These are the coldest to hottest temperatures on the entire planet, not average temperatures.
It may be worth pointing out that the known range on earth (going by satellite observations rather than weather stations, which tend not to be in the most uninhabitable places) is -90 > 70. So this planet is a bit warmer than Earth. But I'm skeptical of these numbers, for which see below...
  • Atmospheric pressure: 0.7 atm
For context, this is about equivalent to an altitude on Earth of around 3,000m, I think. So if you dropped humans onto the plains on your planet, they'd probably get altitude sickness, but it's a long way from being in the Death Zone. Humans could adapt to the altitude at that level - they'd be similar to Himalayan or Andean populations physically; however, they probably ought to stay away from any upland areas and certainly shouldn't go mountain climbing.
  • Atmospheric composition:
    40–48 Nitrogen (average 44.8%)
    20~39% Oxygen (usually ~34.52)
Humans will probably be getting serious oxygen toxicity symptoms, though probably not instant death. Lower atmospheric pressures help with this, but probably 0.7 isn't enough to help too much? I don't know, this requires biology way beyond me, and probably beyond what anyone has studied (most of the concern around hyperoxia is in high pressure diving situations, not low pressure atmospheres...)
Actually, come to think of it, combining the low pressure with the high oxygen might give safe partial pressures... have you calculated this?
At any rate, even ignoring the low pressure, this isn't too much oxygen for life in general. Earth has had up to 35% oxygen in the past, and had 30% at the time of the dinosaurs.

Putting together a few things: expect humongous animals! Lots of oxygen makes bigger sizes more efficient (dinosaurs!), and your low gravity will also help with that. [Unless that low pressure is too low?] Don't expect lots of flying things, though - you'd think low gravity would help, but apparently the atmospheric pressure is likely to be a bigger factor.

By the way, how come oxygen in some places/times is twice what it is elsewhere/when? Won't the gas diffuse? Does that really happen on earth?
10–13.35% Carbon dioxide (usually ~10.35)
This is the killer, for humans. Literally. CO2 at 0.5-1.0% can make people giddy, and can have chronic side-effects. It's been hypothesised that people might be able to live at 2% with sufficient time to adapt. At 7%, you're feeling overwhelming symptoms and may be dead in minutes or hours. Note that this isn't due to lack of oxygen, so higher oxygen levels won't help you - it's due to the toxicity of the CO2 itself.

Unlike your oxygen levels, this is totally outside anything earthlike. Earth is hypothesised to have had up to 0.7% CO2 at the beginning of life, but is modeled as never having had much over 0.2% in the last 350 million years or so. 10% is... something else. My worry with 10% CO2 is with the greenhouse effect. Apparently our tiny 0.04% CO2 gives us about 33 degrees extra in global temperatures... what would 10% do? Well, it would surely melt the surface of the planet. Apparently it would only take surface temperatures near 50 degrees (compared to our 14 degrees) to trigger venusian runaway greenhouse effects and temperatures in the thousands of degrees in the near future.

Now, on the other hand, you have a weak sun I think, so maybe that extra insulation is just keeping an earth temperature? That seems theoretically possible to me, but I don't know the numbers (or whether anyone knows those numbers)... and I strongly suspect that an increased in CO2 of that magnitude could never be good news. If there is a habitable zone in the 'cold sun big greenhouse' scenario, hitting it would be like dropping a needle on the edge of a playing card. Besides, your tiny year presumably means a very close sun, so I doubt your planet starts off cold at all.

There's also the problem of how you get so much CO2 anyway. Is there no tectonic drift to remove it, or is the whole place just a belching volcanic hellscape? Neither option sounds good for life.

0.00012–~7% Water vapour (climatic variation)
Presumably you must have VERY hot tropics?

I have seen two main methods of making climates: one uses tropics and poles defined by axial tilt and the other uses cells, whose number is determined by equatorial rotation velocity and size is determined by the distance warm winds can travel in the conditions of each cell (as I don’t know the equations, I just assumed a Hadley, Ferrel, and Polar cell, with the Hadley at 31.5°). Which one is responsible for climates in real life? If the answer is both, is there a way to combine the methods?
Atmospheric cells define the climate in a given season. Axial tilt tells you how the seasons change.

However, I suspect you don't have any seasons. For one thing, axial tilt is low, so there are large bands with limited seasonality anyway. But for another, the year is so short that I'm not sure the atmosphere really will have time to react to the changes - it takes time to heat up or cool down.

So I suspect you have fairly static climate bands, which in turn suggests great extremes of heat and aridity. Your desert zones may well be entirely impassable.

Plus, you know, the whole 'hellscape scoured and melted by the abominable atmosphere' thing.
Finally, are there a way of determining tidal patterns for different moon systems and climates in the ocean? As one of the inhabitants is an intelligent amphibious creature that live mainly under the ocean, I need a complex way to determine how they live in different ocean locations.
I’m not asking for anyone to make my planet description. All I want is equations, and then I can plug what I want for all the variables and fix everything wrong on my own.
You cannot calculate the tides. At minimum, this requires knowing a lot about harmonics, and all the details of the relative rotations and orbits of your bodies. But then you also have to take into account resonant frequencies of ocean basins, and the effects of the contours of the sea floors, and the effects of salinity on friction, and so on, and you're into supercomputer areas.
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Re: Climate thread for bizarre cases and pedantics

Post by mèþru »

Thank you. I knew that in Siphonia (https://web.archive.org/web/20150926122 ... /S/SIP.HTM) oxygen is much higher than on Earth, and in Dubia (https://web.archive.org/web/20150415232 ... /DUBIA.HTM) carbon dioxide is higher than on Earth. The figures are probably much smaller. The idea of lowering air pressure occurred to me randomly :). However, Siphonia did use a combination of increasing oxygen and decreasing pressure. Chris Wayan calculated the results, and, according to him, it actually makes big brains easier to maintain. Like Almea, my world is inhabited by alien creatures almost identical to our own (whether they are related to us somehow is a purposefully open question). This means that all conspecies are adapted to any peculiarities. My main concern with the change in atmosphere is the dramatic drop in nitrogen concentrations. Here are the new figures for atmosphere:
40–48% Nitrogen (average 44.8%)
31–39% Oxygen (usually ~34.52)
0–4% Water vapour (usually ~1)
0–4% Carbon dioxide (usually 2)
~1% Methane (depends on amount of large animals)
0–8% Other
One of the reasons for the drastic variations is that one of the moons has an atmosphere of its own. This causes occasional exchanges during that moon's periapsis. The second reason is that I knew that there is a little variation on Earth. That variation is probably less than a hundredth of a degree. The last reason is that looked cool. Until I find more reasonable figures for the moon, I'm going to stand by my ridiculous ±4% variations.
As for the part which talks about continents and water, forget the first. I forgot to delete it. A more accurate description is:
More than 70% of land is on a single, fat, vertical “belt” of land. About 18% is distributed between two fat and short islands. Each ocean gets one of them. They are far from the same size. The rest is archipelagos and lone islands (both of which are common in the ocean with the larger of the giant islands, and rare on the other).
I was hoping that the vast underground networks of freshwater rivers and lakes might hydrate the interior, as well as several convenient giant lakes.
EDIT
I checked Chris Wayan's other worlds and decided that CO2 needs to go down. I'm changing the other numbers too. Wikipedia says that variation in water vapour is from about 0.001%–5%, and it is not included in dry climate measures (the lowest number there is methane at 0.000179, so water vapour in dry climates probably is below that number). I have hunch that the wettest areas of Kårroť, my conworld, are wetter than Earth's, and there are the scorching deserts that you and the climate guides predicted guides, of course.
48.96–57.8% Nitrogen (average ~53.8%)
31–35.42% Oxygen (usually ~34.52)
0–7% Water vapour (usually ???)
0.03–1.62% Carbon dioxide (usually ~1.4)
0.78–1% Methane (depends on amount of large animals)
<0.01% Argon
<0–2% Other
Do massive (in relation to the mass of Earth's atmosphere over Earth's mass) atmospheres mean higher atmospheric pressure?
Last edited by mèþru on Sat Jan 23, 2016 4:18 pm, edited 1 time in total.

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Re: Climate thread for bizarre cases and pedantics

Post by mèþru »

There are also variables such as orbital eccentricity and planet composition (which sets albedo, gravity, mass, magnetism) and radiation. I don't know a lot about the second two. I think that there will be a magnetic shield similar to Earth's and there is very little NaCl compared to our world. If the axial tilt is not enough to produce seasons in the (sub)tropical areas, then a high eccentricity will force seasons on the entire planet. My only problem is that I forgot to record the equations used to find the year. I know I used the PCk's L = M3 and d = L0.5. I then increased d by a percentage I can't remember. After that, p2 = d3. The result was rounded to the nearest billionth and all the numbers before rounding were deleted. I will have to reconstruct my thoughts to find it, and that is a daunting task. The reason for why I haven't set the location of surface materials is because I need to know where they would be useful. I don't anything about internal composition. Tectonic activity is a major variable, but I decided that it is more or less like Earth.
I wonder...is Chris Wayan of Planetcopia and World Dream Bank still active? Does anyone know if he moved to another site or uses any forums?
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Re: Climate thread for bizarre cases and pedantics

Post by mèþru »

Okay, new info:
Mass: ~0.65 earths

Here's what I want regarding moons:
  • One moon is a water world with a large core. It has a mass of 0.02182375 earths and a radius of 0.293811346 earths. It has an atmosphere with nitrogen, oxygen, water vapour (well duh) and carbon dioxide in it. The exact proportions in the composition of both the planet and the atmosphere don't actually matter that much as long as the planet is entirely covered by water, but I'd like something like this: something like 47.5% iron, 22.5% silicate and the rest is water.
  • The other moon has no water other than that which was brought by comets/asteroids. It has a mass of 0.021761789 earths and a radius of 0.236 earths. The moon’s composition is as vaguely like Charon or Luna as a moon this dense can be. This moon has no atmosphere. Again, compositions doesn't matter that much. In fact, it matters much less for this moon than for the watery moon.
  • The moons are co-orbital.
  • The moons appear to be at an equal distance from the perspective of someone on kårroť, whether they actually are or not.
  • The moons appear to be close in size (acceptable) or identical in size (preferred) from the perspective of someone on kårroť.
  • Tides on kårroť are impacted by both moons. Tides on the watery moon are caused by kårroť and the sun (I can accept the rocky moon playing a role).
I have been trying since somewhere like April or June to make a lunar year. Not knowing the cycle of the moons is frustrating.
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Re: Climate thread for bizarre cases and pedantics

Post by Soap »

Ive always been a freestylist with climate development, and I think people here are far too conservative with the rules. Just look at the wide variety of climates in our solar system, for example, such as Jupiter with its 9 atmospheric cells and a 200-year-old storm straddling two of them in the Southern Hemisphere, or Uranus with its 98° axial tilt, or Mars with its highly eccentric orbit, or Venus with its day-long years (or year-long days). I think that any or all of those things could exist on an Earthlike planet that supports life, though I suspect the Jupiter thing might bring with it some other features that would make advanced life difficult.

That said, I remember reading somewhere that advanced life is unlikely to develop on planets that are significantly smaller than Earth. I dont remembner where I read it (it wasnt the Climate Cookbook) or what the reason was, but it might be worth looking into.
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Re: Climate thread for bizarre cases and pedantics

Post by mèþru »

This planet isn't that much smaller. It is like 61% the volume with 72% the surface area of Earth. The gravity is like 90% of Earth's.
ìtsanso, God In The Mountain, may our names inspire the deepest feelings of fear in urkos and all his ilk, for we have saved another man from his lies! I welcome back to the feast hall kal, who will never gamble again! May the eleven gods bless him!
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