Water and Terrain in Eccentric Orbits

[Steve Walmsley (OP)]

I'm about six years in my test campaign for v2.00 and I've discovered 48 systems, which means I have already encountered several challenges in dealing with eccentric orbits.

As an example, I've found what would looks like an amazing planet. Great mineral resources and a diameter of only 3200 km, making it easy to terraform. However, it has an eccentricity of 0.61 and it orbits between 6m and 26m km from the M3-V primary. So far I have added 0.37 atm of atmosphere, including 0.06 atm of water vapour.

Alexandria-A II Survey Report
Duranium:   2,320,076   1.00
Neutronium:   21,670   0.50
Tritanium:   5,921   0.90
Boronide:   1,584,327   0.80
Mercassium:   8,861   0.90
Vendarite:   1,618,984   1.00
Uridium:   375,773   0.90
Corundium:   1,380,521   0.60
Gallicite:   1,446,752   0.70

The temperature ranges from -78C to 122C over a 23 day orbit, which has two effects. Firstly, the water is frozen, liquid and vapour at different points of the orbit, with a knock-on impact on albedo and water-related colony cost. Secondly, the dominant terrain changes multiple times per orbit.

Given the above, I am wondering whether to change hydrosphere type and dominant terrain to be fixed for the entire orbit unless the environment changes via without terraforming. If I do make them fixed, I also need to decide the parameters. For example, should the dominant terrain be possible across the whole temperature range, or based on the average temperature? If average, should that be based on a straight (min/max) / 2 or take into account that planets will spend more time at the min temp due to orbital speed.

Hydrosphere would have to be based on some sort of average because there is no single state that could exist across all possible temperatures. Or maybe I invent a fourth state for water, that can be applied in that case and has its own effect on colony cost and albedo.

Also, does the year make a difference. This planet has an orbital period of 23 days, but others could be years or decades.

Finally, leaving things as they are is also a reasonable option. In this case, colony cost would reach 2.00 at certain points in the orbit due to the water evaporating. I would have to bring the temperate range down, accepting a lower temp at the minimum to bring the max temp within the liquid water range. Terrain changing regularly only affects ground combat and surface-to-orbit. Invasions would have to be staged in the best 'season' for the attackers.

I'm laying all this out to spark discussion

[alex_brunius]

Would it make sense to add some inertia to the hydrosphere type or have larger hydrospheres provide some inertia to planet temperatures?

It's probably not very realistic to have planetary sized bodies of water swap from frozen solid to steam and then back again in a matter of days.

[Marski]

Maybe make it possible to spacemaster/technology mumbo-jumbo the orbit into more stable one?

[Steve Walmsley (OP)]

Would it make sense to add some inertia to the hydrosphere type or have larger hydrospheres provide some inertia to planet temperatures?

It's probably not very realistic to have planetary sized bodies of water swap from frozen solid to steam and then back again in a matter of days.

Interesting idea. In the past, the change from liquid to vapour was instant because it was always the result of terraforming and therefore likely to be permanent. Maybe the change should be gradual in the same way as condensing (0.1 atm per year). That would solve the problem of drastic changes in short orbits while leaving the option of different conditions in long orbits.

Liquid to ice and back is less of an issue because it only affects albedo and doesn't introduce a sudden 2.0 colony cost (and I already include albedo changes in the min/max temperature and min/max colony costs). I could perhaps track the percentage of water that is frozen, rather than having separate states, but in reality the water to ice process happens quite quickly so probably not worth it.

[nuclearslurpee]

Would it make sense to add some inertia to the hydrosphere type or have larger hydrospheres provide some inertia to planet temperatures?

It's probably not very realistic to have planetary sized bodies of water swap from frozen solid to steam and then back again in a matter of days.

I think this is a good solution, having a sort of inertia for the hydrosphere and climate type which can be tied to the body size. This seems like an approach that is not too difficult to understand for players but allows slower transitions (a planet with a 100-year orbit that changes its climate over those 100 years would be cool!) but not unrealistically rapid shifting of the terrain class every five days. After all, flora and fauna take time to grow, live, and die, 23 days is not enough time for such an ecosystem to adapt but 100 year cycles may be, certainly some interesting life forms would evolve under such conditions.

[Kiero]

Terraformers/Tugs that can change planetary orbit!

[serger]

I think it's very strange to have dominant terrains changing from Taiga/Forested/Jungle to Desert and so on every 23 days or even less (no type of forest is capable to rise so fast!), and there will be no arbitrary point for every pair of terrains transition time. So I think the only way with eccentric orbits is to unite those terrain types, which differences are only biological. More so that I think there are strange things, too, that:
1. Some strange significant difficulties with biome for TN-equipped armies capable of garrisoning every airless frozen or venusian stone-burning hell without tension;
2. We can choose planetary dominant terrain based on biome types, nearly equally presented in Earth (and really there are more tundras, savannas, steppes and deserts on Earth comparing to temperate forests, and the only thing Temperate Forest is common - in the past - it's for those countries our technological civilization was born in historically).

So I think Terrain Type might reflect only geological types like [Flat, Rifty, Mountainous, Volcanic] with a (potentially changeable) type of Oceanic where there is nearly no dry land to make any of those types relevant.

[Zap0]

As for terrain, it'd make sense if the planet just kept one based on it's average temperature. It makes sense to assume that the landscape has come to some sort of stable state after undergoing the same cycle for millenia. As for which average, just pick one you're already displaying on the system view so you don't have to display another one :-)

Counterpoint: On a planet with long cycles it'd make sense if the vegetation changed enough to turn a rift valley into a jungle rift valley for a decade or two and then died off again as the long winter approaches. But one can argue that using the mintemp+maxtemp/2 average instead of the "longer in the cold part of the orbit" average favors higher temps and therefore the more vegetated terrains, representing such cases with temporary vegetation better.

The main argument for not changing the terrain is not introducing more complexity than is needed or easily understandable. For one key planet having such a mechanic may be neat, but for a hundred other rocks that change some part of themselves over the course of their orbit you're probably just going to sigh that this weird interaction threw you a wrench in the works again.

The water changes on your planet in particular are egregious, and I'm also in favor of keeping them in one state. We already have tide-locked planets that may have several states of water on them at the same time, and much like with the terrain, it stands to be reasoned that there is some stable and predictable water cycle the planet has developed.

[serger]

As for vegetation... There is no option to have any sort of soil on anoxic planet. No life - no sod - no soil. There will be plenty of rocks, sand and mineral dust, yet to have a soil or even clay (except on oceanic abyssal flat) - you need at least thousands of years of ubiquitous terrestrial vegetation.

So I think it will be cool to have this feature: a boolean field Soil Layer, possible for the same planets that have oxygen, mandatory for homeworld planets, can be erazed with backing (I'd say average surface temp 1000C), cannot be restored during playtime, mandatory for <1.50 CC.

[Zap0]

As for vegetation... There is no option to have any sort of soil on anoxic planet. No life - no sod - no soil. There will be plenty of rocks, sand and mineral dust, yet to have a soil or even clay (except on oceanic abyssal flat) - you need at least thousands of years of ubiquitous terrestrial vegetation.

So I think it will be cool to have this feature: a boolean field Soil Layer, possible for the same planets that have oxygen, mandatory for homeworld planets, can be erazed with backing (I'd say average surface temp 1000C), cannot be restored during playtime, mandatory for <1.50 CC.

Two things: If you can't create a soil layer, how could you ever fully terraform Mars and other planets?

And what about alien biologies? Even if they'd be incompatible with human/Earth biology, large alien plants could still provide the cover that the terrain modifiers represent.

[Density]

Liquid to ice and back is less of an issue because it only affects albedo and doesn't introduce a sudden 2.0 colony cost (and I already include albedo changes in the min/max temperature and min/max colony costs). I could perhaps track the percentage of water that is frozen, rather than having separate states, but in reality the water to ice process happens quite quickly so probably not worth it.

Does this mean adding ice will lower albedo in 1.14/2.0?

[Steve Walmsley (OP)]

Liquid to ice and back is less of an issue because it only affects albedo and doesn't introduce a sudden 2.0 colony cost (and I already include albedo changes in the min/max temperature and min/max colony costs). I could perhaps track the percentage of water that is frozen, rather than having separate states, but in reality the water to ice process happens quite quickly so probably not worth it.

Does this mean adding ice will lower albedo in 1.14/2.0?

Water to turning to ice and vice versa already changes albedo in v1.13.

[Density]

Does this mean adding ice will lower albedo in 1.14/2.0?

Water to turning to ice and vice versa already changes albedo in v1.13.

I was refering to

Yes, although I probably should change it so that adding ice reduces Albedo.

which I haven't seen mentioned in any of the Changes Lists.

[KriegsMeister]

I don't know the exact math, but shouldn't atmospheric pressure have an insulatory effect regulating the extreme temperature radiation.  I know on a daily scale this is important in comparing min/max day/night temperatures between earth, Mars and mercury, and I would assume the effect would be present though likely not as strong for longer time scales for orbital eccentricity.

Could maybe even add another -isium type gas that reduces temperature variation.

[Bremen]

What about just adding a new environment/hydrosphere for sufficiently eccentric planets? IE on that planet instead of swapping back and forth between them it would just say Environment: Extreme Variations and Hydrosphere: Seasonal?

My concern with giving inertia to the hydrosphere is that it might complicate terraforming. Hydrosphere changes albedo, which normally isn't an issue since it shifts instantly, so if you're adding greenhouse gases to a planet at some point you'll get a message the hydrosphere has melted and that bumps the temperature up further. But if there's a delay, that could mean terraforming too quickly would result in you getting the planet up to a pleasant temperature, then the hydrosphere melts and the temperature jumps past the high end of tolerance.