Glaciologist Dr. Heïdi Sevestre and explorer Matthieu Tordeur spent the 2025/2026 Antarctic summer crossing the continent by kite-ski, covering nearly 4,000 kilometers while pulling two ground-penetrating radars across the ice to collect data on snow accumulation, internal ice layers and the structures hidden deep beneath the surface. This expedition is known as Under Antarctica Expedition.
A lighter footprint
At a time when climate change is a global threat rapidly reshaping the polar regions, advances in field work are essential to understand physical processes and refine projections of the future. Yet Antarctic research typically relies on aircraft and overland tractors, which are effective but logistically heavy and carbon-intensive. Sevestre and Tordeur wanted to see whether serious geophysical data could be collected without that infrastructure. By harnessing wind to move themselves and their equipment, they completed the first ever radar transect by kite ski, under conditions that rarely rose above -30°C and dropped below -50°C with wind chill.
Progress, as with all kite expeditions, was at the mercy of the weather. A good day could cover tens of kilometers, whereas a still day meant staying in camp, requiring physical endurance along with patience.
The Pole of Inaccessibility
After 42 days and nearly 1,800 kilometers travelled, the pair reached the Southern Pole of Inaccessibility, the point on the Antarctic continent furthest away from any coastline, about 1,400 kilometers from the nearest shore. It is one of the least-visited places on Earth. They became the fifth expedition to reach it by kite-ski, the first French team to do so, and Heïdi Sevestre became, to the best of current knowledge, the first woman to arrive there by this means.
They reached the geographic South Pole at day 61, having covered 2,700 kilometers in full autonomy. After two months on freeze-dried food, a hot meal and two and a half days of rest felt like a luxury before the final stretch.
What comes next
The radars recorded a continuous profile of the ice throughout the traverse, capturing subglacial lakes and rivers along the way. Analysing and publishing that dataset will take years. But the expedition has already made its broader point: that low-impact fieldwork in Antarctica is possible, and that the people leading it are changing too.
For Sevestre, known as much for her public communication of climate science as for her research, the crossing was both a scientific contribution and a proof of concept. The two, it turns out, are not mutually exclusive.
Léa Zinsli, PolarJournal