Morphology of Antarctic Polygons and Implications for Polygon Evolution and Subsurface Ice Dynamics

Polygonal terrain results from thermal contraction, is commonly found in periglacial environments, and serves as a valuable proxy for interpreting subsurface ice distribution and climate history on Earth and Mars. In this study, we investigate the morphology of polygons in Beacon Valley, Antarctica, to assess the relationship between polygon size and ice table depth and to evaluate whether existing models for ice‐cemented soils apply to polygons overlying massive ice. Using high‐resolution remote sensing imagery and lidar datasets, we mapped over 1500 polygons and compared their sizes to measured ice table depth. Statistical analyses indicate that polygons formed over massive ice are generally smaller than those formed on ice‐cemented soils. This observation contradicts current models, which predict larger polygons on massive ice due to a reduction in stress through viscous flow. We propose that sediment within the glacial ice inhibits viscous deformation and lowers tensile strength, thereby reducing the size of the observed polygons. Our statistical analysis also reveals two distinct subpopulations of polygons, for both polygons on ice‐cemented soil and massive ice, which we interpret as evidence of polygon time evolution. This observation is supported by a crack propagation model that illustrates how polygon size decreases with time. Our findings challenge prevailing models of polygon formation and evolution and offer a revised conceptual framework with implications for interpreting subsurface ice availability on both Earth and Mars.