Antarctica Froze First: Here's Why

Earth's southernmost continent, Antarctica, developed its massive ice sheet approximately 34 million years ago, a phenomenon that occurred tens of millions of years before the Arctic region began to freeze. Researchers have now identified a powerful geological process as the key to this polar asymmetry.

Mantle waves, slow-moving disturbances within the Earth, caused renewed uplift of a mountain range in eastern Antarctica. This geological activity elevated the continent's topography, enabling glaciers to form and stabilize. The Gamburtsev Mountains, now buried under ice, played a critical role as their elevation surpassed a threshold necessary for ice accumulation, even during a warmer global climate.

In contrast, the Arctic lacks significant landmass at the North Pole, which is situated in the Arctic Ocean. This meant the terrain could not reach the necessary elevation for permanent ice to form until global temperatures cooled considerably. The climate had to become colder, largely due to reduced atmospheric carbon dioxide concentrations, before substantial ice sheets could establish in the Arctic less than 10 million years ago.