Full Breakdown
Why Antarctica Frozen Over First: Mantle Waves, Uplift, and the Birth of the East Antarctic Ice Sheet
7/4/2026, 11:27:02 AM
Mantle Waves Raised East Antarctica
Mantle waves—disturbances generated during continental breakup—lifted eastern Antarctica above a critical elevation. The uplift created a high plateau crowned by the Gamburtsev Subglacial Mountains, enabling permanent ice to form around 34 million years ago despite global temperatures about 5 °C warmer than today.
Gondwana Breakup and the Rise of the Gamburtsev Mountains
During the Jurassic (?201–143 Ma) Gondwana split, separating Africa, South America, Australia, and Antarctica. Mantle waves from the rifts removed dense lithospheric rock, causing uplift that persisted into the Eocene-Oligocene transition and produced the buried Gamburtsev Subglacial Mountains, a key highland for later ice sheet growth.
Study Team and Modeling Approach
The study was led by Thomas Gernon and Thea Hincks (University of Southampton) with input from Guy Paxman (Durham) and John Goodge (University of Minnesota Duluth). Simulations linked uplift timing to ice sheet stability, testing scenarios with and without the modeled elevation changes.
Elevation Thresholds and Ice Sheet Timing
Models show a 1.5–2 km elevation is needed for snow. By ~45 Ma East Antarctica passed this threshold; by 34 Ma 90 % of the Gamburtsev region was above it, allowing an ice sheet. The Arctic, lacking land at the pole, did not develop ice until CO2 fell below a level less than 10 Ma ago.
Climate Significance
The research demonstrates that tectonic uplift can give a “head start” for glaciation, interacting with atmospheric cooling to shift Earth from a greenhouse to an icehouse state. This explains why Antarctic glaciation preceded Arctic ice sheet formation and highlights topography as a driver of climate change.
Conflicting Timelines and Data Gaps
The primary model dates permanent Antarctic ice to ~34 Ma, but alternative simulations allow uplift-driven ice as early as 40 Ma. Arctic ice sheet timing is debated, with estimates from intermittent glaciations over the past 50 Ma to a stable sheet forming less than 10 Ma ago. Rock samples from beneath the Gamburtsev Mountains are scarce, limiting verification.
Future Research
The authors propose deep drilling beneath the ice-covered Gamburtsev range to retrieve lithospheric material for testing uplift models. They also call for international funding of Antarctic geoscience to refine the ice sheet chronology and improve projections of climate dynamics.
Verbatim Quotes
- “Our study shows that an ancient geological process that started more than 160 million years ago during the continental breakup of Africa and Antarctica and played out over many tens of millions of years determined when and where Earth's major ice sheets could form during the Eocene-Oligocene transition, approximately 34 million years ago,” — Thomas Gernon, University of Southampton
- “These waves can remove dense rock from the underside of tectonic ?plates, making the continents lighter and causing them to rise, ultimately forming high ground such as plateaus and mountain ranges,” — Thomas Gernon
- “Our study underscores the importance of the interaction of changing climate and changing topography,” — Thea Hincks, University of Southampton
- “Air temperatures can drop by up to 1C for every 100 metres of altitude gained.” — Guy Paxman, Durham University
