High CO2 levels during the Eocene put Antarctic temperatures into a place of warmth that likens it to California. And more. The sea around it was 22 degrees Celsius (72 F), like the Florida coast is today...

Guillarmo del Toro's sketches show how he would show The Mountains of Madness by H.P. Lovecraft with the horror in action before the Antartica temperature gets back to the olden days.