A scenario for the recent evolution of water ice at the South Pole of Mars,
summarizing the sequence of events in the south polar region since the precession cycle of Mars was last inverted. At that time (1), water was extracted off the north polar cap and was deposited over the south layered terrains. The passage to present-day configuration (2), with inverted precession cycle, forced water to progressively return back to the North Pole. In a third act (3), the water-ice erosion process stopped as permanent CO2 ice slabs formed and kept water from subliming further.