We still have a good few thousand years until we make the Earth anywhere close to as inhospitable as the second best planet in the Solar System - and probably much more than that before we run out of space on Earth.
It makes far more sense to colonize the Arctic, the Gobi desert, the peaks of the tallest mountains, and similar places here on Earth before even contemplating the colonization of Mars. Let's first have a 10M-strong self-sustaining megacity at the South Pole before contemplating absurd projects like a Mars colony.
It makes far more sense to colonize the Arctic, the Gobi desert, the peaks of the tallest mountains, and similar places here on Earth before even contemplating the colonization of Mars. Let's first have a 10M-strong self-sustaining megacity at the South Pole before contemplating absurd projects like a Mars colony.