In a recent paper published in Nature Geoscience, a team led by a research team from Université Grenoble Alpes in France and the Institut de Physique du Globe de Paris, used satellite data, including Copernicus Sentinel-2 imagery, to identify and analyse snow dunes.

The research team analysed over 33,000 satellite images taken between 2018 and 2021, covering an area of approximately 7.5 million square kilometres, or 60% of the Antarctic continent. Their findings reveal that the dunes are primarily shaped by wind-driven snow transport and limited by a process known as snow sintering.

Sintering, which involves the bonding of snow particles through gradual ice bridge formation, plays a key role in determining the availability of snow particles for transport. In Antarctica’s extreme conditions, this process slows down the movement of snow, allowing dunes to grow through elongation rather than accumulating in height like traditional sand dunes.

One of the study’s most significant discoveries is the widespread prevalence of longitudinal dunes, which account for 61% of the formations observed. These dunes form under unidirectional wind regimes, where strong and consistent winds stretch the snow into long, narrow shapes.

This pattern was especially prominent in East Antarctica, where large stretches of dunes align with winds that rush down from the high interior toward the coasts.

Using the results of a theory developed for sand dunes, the dominance of longitudinal dunes points to a broader conclusion: snow availability in Antarctica is limited across much of the continent.

Even in coastal regions, where snowfall is relatively high, strong winds often erode and remove snow before it has a chance to accumulate, leading to the creation of elongated snow dunes rather than taller, more complex formations.