Geological uplift, not just global cooling, explains Antarctica's early glaciation

Scientists have identified a key geological factor that led to Antarctica's glaciation approximately 34 million years ago, significantly earlier than the Arctic's freezing. Research published in the journal Science reveals that a powerful geological event caused a mountain range in East Antarctica to uplift. This uplift raised the landmass to an altitude conducive to glacier formation and permanent ice accumulation, even though global temperatures were about 5 degrees Celsius warmer than today. This process occurred at the beginning of the Oligocene epoch, following the Eocene. The uplift was driven by mantle waves, slow-moving disturbances deep within the Earth that occur when continents break apart. These waves shifted dense rocks from beneath the tectonic plate, causing the overlying continent to become lighter and rise. This led to the formation of the Gamburtsev Mountains, an 11,120-foot-high range now buried under ice. The increased elevation created a stable environment for ice to form and persist. In contrast, the Arctic, being primarily an ocean with no significant landmass or mountains, could not accumulate permanent ice until atmospheric carbon dioxide levels dropped considerably, making the air much colder near sea level. This difference in geological structure and elevation explains why the Arctic froze about 25 million years after Antarctica. The study, co-authored by geoscientist Thomas Gernon of the University of Southampton, highlights how changes in land elevation can have profound impacts on climate and nature, independent of global temperature trends.