Quote Originally Posted by MrBragg View Post
1) whether it's appropriate to add this type of sea ice cover since there is no land up there (as you say, feedback is potentially quite important), and 2) whether the ice-free version accurately reflects the temperature distribution or whether that is "too mixed" and thus too warm in the winter. As a baseline initial test, I'd be curious to see what ExoPlaSim predicts for a water world so I could compare that to a Cilma-sim water world output, I just need to find the time to run that test...
1, Clima-Sim should determine sea ice cover on its own.

2, Not too sure what you mean by "too mixed". The general approach I'd advise if you're aiming to have ice caps is to begin by over-estimating the extent of ice, running the model, and then remove ice from areas that get over 0 C in summer (be sure you're looking at temperatures at the surface, not sea level), and iterate until you find an equilibrium.

Regarding the test you ran with Antarctica, there should indeed be a significant difference there--and you'd be surprised how warm polar regions can get without ice thanks to constant sunlight in summer. This might be overstating it a bit though; Clima-sim doesn't seem to do a good job of allowing heat to flow from the poles to lower latitudes when the former gets warmer than the latter, which is why it essentially breaks at higher axial tilts.

re: Peter, I took a look at morne's world and that high-latitude desert is a reasonable outcome of a large mountain range casting a large rainshadow. ExoPlaSim has its weaknesses (most notably the low resolution, static glaciers, and lack of deep ocean currents) but it's in a whole other league compared to Clima-sim in terms of the complexity and accuracy of the underlying simulation and its flexibility in handling a range of climate parameters.