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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...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.
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.
- 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.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...)
- Atmospheric composition:
40–48 Nitrogen (average 44.8%)
20~39% Oxygen (usually ~34.52)
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?
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.10–13.35% Carbon dioxide (usually ~10.35)
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.Presumably you must have VERY hot tropics?
0.00012–~7% Water vapour (climatic variation)Atmospheric cells define the climate in a given season. Axial tilt tells you how the seasons change.
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?
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.