Ukrainian Antarctic scientists observe rare 'snow donut' formation

Ukrainian scientists at the Vernadsky Research Base in Antarctica have documented a rare atmospheric phenomenon known as "snow donuts" or snow rollers, the National Antarctic Scientific Center (NASC) reported.

The formations are multi-layered cylindrical snow rolls, often hollow at the center, ranging from a few centimeters to more than one meter in diameter. Photographs released by the center show dozens of the structures scattered across the ice near the station.

NASC meteorologists said three conditions must coincide: two distinct snow layers of different density, air temperature just above freezing, and wind strong enough to initiate rolling without breaking the fragile structures. The wind acts as a natural sculptor, gathering loose surface snow into coils as it moves across the harder underlying layer.

While documented in polar regions and occasionally in temperate zones during unusual winter storms, the phenomenon remains infrequent, providing valuable data on wind dynamics and snowpack physics. Ukrainian researchers have maintained continuous meteorological observations at Vernadsky since the station's transfer from the United Kingdom in 1996.

The latest sighting adds to a growing record of cryospheric anomalies monitored by Ukraine's Antarctic program, which operates year-round at the base on Galindez Island off the Antarctic Peninsula.