Finite element modeling of glacier-bed evolution: a case study of Xue Mountain Cirque No. 2, Taiwan

This study develops a finite element framework that couples nonlinear Stokes flow with a basal sliding-driven erosion law to reconstruct the evolution of the glacier bed in a subtropical, low-latitude alpine cirque. Applied to the well-preserved Cirque No. 2 on Taiwan’s Xue (Syue) Mountain, this model provides the first physics-based quantitative constraints on glacier erosion in a low-latitude environment. Quasi-steady Stokes–sliding simulations over a 1,000-year interval reproduce the downward migration of the ice–bed interface and yield erosion velocities consistent with empirical estimates. By comparing the simulated bed evolution with the present cirque topography derived from publicly available contour data, we identify parameter combinations that are consistent with the ~9,000-year glaciation interval inferred for the Last Glacial Maximum. The results demonstrate how sliding efficiency, erosion constants, and ice geometry jointly regulate cirque erosion, offering a quantitative basis for reconstructing alpine glacier-bed evolution in data-sparse mountain regions.