Final answer:
The third step of the warm arctic cold continents pattern refers to a period of global cooling resulting from reduced atmospheric CO2, leading to the formation of ice sheets in Antarctica and changes in ocean currents.
Step-by-step explanation:
The third step in the hypothesized warm arctic cold continents pattern involves a global cooling that is driven by lowering CO2 levels.
This cooling leads to the formation of permanent ice sheets in Antarctica, affected by CO₂ lowering past a critical threshold and changes in ocean circulation patterns due to the shifting positions of the continents.
It is part of a larger discussion on how changes to Earth's climate, including warming trends leading to melting polar ice caps and changes in seasonality due to Earth's tilt and orbit, can impact environments and consequently, modern civilization.