The Arctic Coastal Erosion (ACE) Model is a multi-physics simulation tool that couples oceanographic and atmospheric boundary conditions with a terrestrial permafrost domain to capture the thermo-chemo-mechanical dynamics of erosion along permafrost coastlines. It solves 3D heat conduction with phase change (thermal problem), and the development of stress/strain according to a plasticity material model (mechanical problem). The permafrost material is represented by a porous media composed of sediment grains and pore fluid, and mechanical properties like elastic modulus are dependent on the local ice content determined by solving the thermal problem, which couples the thermal and mechanical dynamics of the permafrost evolution. Oceanographic (external software package) and atmospheric (obtained from reanalysis data sets) boundary conditions provide time-dependent temperature, salinity, and water level information applied as boundary conditions to the terrestrial domain. Erosion is captured via mesh element removal according to stress, strain, and kinematic related erosion criteria such as tensile and compressive yield and strain limit of the material. This enables failure from any allowable deformation such as block failure, slumping, or thermal denudation, and can treat erosion behavior over various time scales (single events, seasonally, or over the course of years). Calibration of a model of this fidelity is intensive -- requiring selection of tensile and compressive yield values, material strain limits, and material weakening due to ocean contact. Results of ACE Model sensitivity studies to enable calibration using 2018 field data from Drew Point, Alaska are presented. In particular, studies identifying the best strain removal to capture denudation, enhanced removal to capture niche formation, and selection of tensile and compressive yield values will be detailed.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

SAND2024-09942