It would never be warm for any land mass at polar latitudes, Antarctica was warm when it was in temperate latitudes. It moved many thousands of miles to end up at the south pole.
That’s a possibility I had not considered. Maybe Antarctica moved south because of the flood.
I don’t know. Like the atheist, I can only ...
1) speculate based on the evidence (Noah’s flood moved stuff, rather than billions of years)
2) according to my world-view (Bible = Word of God, rather than Darwinism)