For the first time, a high-resolution map shows in detail what lies beneath the ice sheet of Antarctica: mountains, mountain ranges, canyons, and thousands of hills. This advancement allows for improved forecasts about sea level and a better understanding of how the continent responds to global warming.
For decades, understanding the Antarctic terrain was like mapping a distant planet. Scientists relied on radar flights and incomplete models that left large areas blank. Projects like Bedmap and BedMachine made progress, but there were still unknowns, especially in the eastern interior.
The IFPA method: reading the ice as a magnifying glass
The new work uses the ice surface itself as a “magnifying glass” to deduce the buried relief.
- The IFPA (Ice Flow Perturbation Analysis) method was applied, interpreting the ice undulations as traces of what lies beneath.
- By combining it with recent thickness data, a continuous map of the relief between 2 and 30 km scale was reconstructed, sufficient to distinguish defined mountains, ridges, and valleys.
The result reveals a surprising ice-free Antarctica: sharp mountain ranges, U-shaped channels similar to alpine valleys, and tens of thousands of hills invisible until now. Some structures could predate the formation of the ice sheet, while others mark tectonic boundaries.
Implications for the future of the ice
The relief is not just a geological whim:
- Controls friction at the base of the ice.
- Accelerates or slows its advance towards the sea.
- Defines possible melting routes in the future.
The map was compared with geophysical surveys and ice dynamics models, confirming its consistency and providing unprecedented details in remote areas. Although it does not capture features smaller than 2 km, the scale leap allows for a much more realistic terrain in simulations and reduces uncertainty about Antarctica’s contribution to sea level during this century.
A window into the geological past
The deep glacial valleys and abrupt ridges suggest there were ice-free periods when water sculpted the landscape. This information will allow geologists to reconstruct the history of the continent’s uplift and erosion and optimize future scientific campaigns: deciding where to fly with radar, drill, or install monitoring stations.
The discovery also resolves a divulgative paradox: for years, we had more detailed maps of Mars than of Antarctica’s rocky bottom. The combination of satellites and ice physics finally reduces that gap.
Next steps
Although new radar flights will be needed to refine the data, the map already allows:
- Drawing probable routes of warm water under floating platforms.
- Identifying bottlenecks that slow down the flow.
- Locating sectors vulnerable to rapid retreats.
With the sea level in the spotlight, this information is essential to anticipate global climate change scenarios.
The new map of Antarctica marks a before and after in polar research. By revealing the hidden relief beneath the ice, it offers keys to understanding the continent’s geological past and, above all, to predicting its future impact on sea level.
