Terraforming mercury

[Kaiser (OP)]

Guys, I am trying to terraform Mercury.

I am adding a lot of Frigusium as first thing to warm up It, but I noticed that the surface temperature goes down says up to 293 celsius and then goes up to 340 celsius and then again down and up, down and up etc..

Am I overseeing something or maybe a weird bug?

EDIT: Same thing goes with Mars, I am adding water vapor, the temperature goes down and up and the terrain keep switching from barren to cold desert and vice versa.

[Andrew]

Orbit is not circular so base surface temperture changes with distance from sun

[Kaiser (OP)]

And why is the hydrographic extent not increasing on Mercury?

[Snoman314]

The water vapour you're adding is not condensing, because the surface temperature is still nearly 400 degrees Celsius. You need to add a _lot_ more frigusium to get the temperature down first. Even at the coldest point of the orbit, the temperature is still way above boiling.

[Kaiser (OP)]

I guess that's the meaning of this (F) next to water vapor on other bodies, condensing or something?

[Snoman314]

I guess that's the meaning of this (F) next to water vapor on other bodies, condensing or something?

Pretty sure that stands for Frozen, or something. Indicates that the hydrographic extent is affecting the albedo, or something like that (All the water is going to white reflective ice, reflecting sunlight and lowering the albedo and therefore surface temperature).

[Ultimoos]

Just to give you heads up, there is a limit the effect greenhouse and anti-greenhouse gases can have in game. For both the factor is limited to 3. Once you reach it, no amount of frigusium will cool temperature further.

[bankshot]

You will need almost 2 atm of Frigisium to bring Mercury down to ideal temperature.  Water will not condense and become hydrographic until temps are below 100C.  If temps fluctuate above/below this it will undergo cycles of condensing and evaporating (I see this on one of my highly eccentric wet planets).  Depending on Mercury's eccentricity you may or may not be able to bring it to colony cost to zero.  In my current game the eccentricity is high enough that temps swing from -16 to 44, so while most of the time it is CC 0 it does increase to 0.05 at perihelion and aphelion.

F stands for frozen gas.  This can be water or other gases like ammonia, methane or even hydrogen if the planet is cold enough.  While frozen it does not count towards atmospheric pressure.  If you raise the temperature the gas can unfreeze and add to atmospheric pressure/conditions.  Note atmospheric frozen water vapor can still precipitate out into hydrographic ice.