Earth's interior dynamics may explain Antarctica's early glaciation

A study in Science suggests that slow-moving waves in Earth's mantle lifted East Antarctica over millions of years, creating high terrain where ice could form even during a warmer global climate. This process, initiated after Antarctica and Africa separated, eventually led to the establishment of the East Antarctic Ice Sheet about 34 million years ago. The findings help resolve why Antarctica froze long before the Arctic.

The research team reconstructed 100 million years of East Antarctic surface evolution using computational models. Their simulations showed that mantle waves—slow-moving deep-Earth phenomena identified by the same research group—lifted the region's terrain past a critical two-kilometer threshold around 45 million years ago. This elevation proved sufficient for mountain glaciers to form and eventually merge into the continental ice sheet.

The study's timeline connects geological separation events to climate outcomes. After Antarctica and Africa began splitting during the Jurassic Period, these deep-Earth forces operated over vast timescales, building the coastal escarpment, elevated plateau, and buried Gamburtsev Mountains. This gradual uplift explains how ice could establish itself despite global temperatures roughly 5°C warmer than present.