When the warmer interglacial periods recurred the polar and continental ice-caps melted and the sea-level became raised again - that is, there was submergence of the eroded plateaux formed as indicated above.
melting of ice caps - the sea level would rise.
What we are talking about here are not the polar ice caps or large ice fields.
Beside, the ice caps are more like a winter frost than the ice caps you get on Earth.
This would eventually cause the polar ice caps to melt, and thus generate an environment in which biological life could be sustained.