Quantifying the Surface Deformation of Pingos on the Alaskan North Slope Using Interferometric Synthetic Aperture Radar (InSAR)

ABSTRACT Pingos are large mounds with cores formed of intrusive ice that form in periglacial landscapes. These ice structures can form in regions of discontinuous permafrost, commonly as hydraulic or open‐system pingos, or in locations of continuous permafrost, commonly as hydrostatic or closed‐system pingos. Using C‐band Interferometric Synthetic Aperture Radar (InSAR) data from the Sentinel‐1 constellation acquired between 2017 and 2025 over the Alaskan North Slope, we quantified interannual surface deformation trends over several hydrostatic pingos. Eight of the 11 pingos analyzed experienced cumulative uplift ranging from 1.49 to 11.35 cm over an 8‐year period, two experienced cumulative subsidence ranging from 0.57 to 2.46 cm, and two experienced no statistically significant surface‐height change. All of the cumulatively uplifting pingos exhibited surface‐height time series proportional to a square‐root dependence with time, which is physically consistent with an aggradational process via Stefan's equation. Ground penetrating radar profiles acquired over select pingos revealed subsurface reflector structures consistent with massive ice cores, reinforcing the hypothesis that the observed surface uplift is driven by intrusive ice formation mediated by elevated hydrostatic pressure due to permafrost aggradation. These results demonstrate that InSAR methods can resolve subtle geodetic signals associated with pingo topographic change, such as from pingo growth due to permafrost aggradation. InSAR observations can thus yield process‐scale insights into the dynamic evolution of pingos and associated periglacial landforms.