Annual dynamics of Arctic lake ice pressure ridge formation in Teshekpuk Lake, Alaska

Lake ice pressure ridges are compression ruptures that typically form due to large air temperature variations, occurring mostly on large lakes in cold environments such as the Arctic tundra and boreal regions. Quantifying pressure ridge occurrence is important for societal (e.g., natural hazards) and ecological (e.g., fish habitat) reasons. Lake ice pressure ridges can be categorized into two main types: overlapped and folded. Overlapped ridges, the more common type, occur when one side of the rupture shifts upward and overrides the other. In contrast, folded ridges develop when both sides of the rupture buckle, creating upward or downward folds. Here, we document the presence and dynamics of an annual Arctic lake ice pressure ridge in Teshekpuk Lake, Alaska, which is the largest (~830 km²) thermokarst lake in the world. We combine (1) field observations, including photos, time-lapse camera, temperature and ground-penetrating radar (GPR) measurements, and (2) remote sensing observations, including satellite synthetic aperture radar (SAR) and uncrewed aerial vehicle (UAV) surveys. GPR (800 MHz) data was acquired on April 29 and May 4, 2022, along several transects perpendicular and parallel to the pressure ridge, showing its internal structure and thickness (up to ~3 m) variation. Lake ice temperature dataset, time-lapse camera images, and UAV orthoimages from late April and early May 2022 revealed that the pressure ridge activity increased as the ice surface temperatures warmed. Moreover, we compiled spaceborne SAR data between 2007 and 2025 to document the distribution of pressure ridges in 5 km grid cells over the time series, revealing that ridges occurred across most of the lake area but preferentially along the lake center and north and south margins. Finally, interferometric SAR (InSAR) data between April 19 and May 1, 2022, shows a common "split bullseye" pattern, indicating failure and buckling of the ice under compressive stress. These findings provide a comprehensive understanding of the formation, dynamics, and spatial distribution of lake ice pressure ridge formation in Teshekpuk Lake, offering critical insights into their ecological and societal implications in the context of a changing climate.