Studies suggest that the evolution of Mars' rotational axis is chaotic and may have varied by as much as 60 degrees over its history. This large and unpredictable range in the orientation of the planet makes Mars' climate history uncertain. A planet's climate largely depends on the characteristics that describe the planet's specific orbit. Specifically, in the case of Mars, its obliquity, which refers to the angle of the tilt of its rotational axis, has a prominent role in the extent of ice cover on the Martian surface. Ice cover is particularly interesting due to its potential implications from geological and biological perspectives. To observe how Mars' changing obliquity potentially impacted ice cover dynamics over time, we use an obliquity-dependent energy balance model examining the incoming and outgoing energy. In this talk, we will discuss our simulations of Mars climate and the different resulting ice regimes. We find that as obliquity changes, there are large oscillations in polar ice cover. We see certain regions of parameter space where the model indicates stable oscillations between partial ice cover and ice-free states. The model also shows no stable partial ice cover on the Martian surface with the poles being ice-free.
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