C001-07
Initial Validation Results for the Arctic Coastal Erosion (ACE) Model

Monday, 7 December 2020: 04:24
Virtual
Diana L Bull1, Jennifer Frederick1, Alejandro Mota2, Benjamin M Jones3, Irina Tezaur1, Chris Flanary4, R Choens1, Melissa Karine Ward Jones5, William Karl Eymold1, Craig Alexander Jones4, Jeremy Kasper3, Emily M Bristol6, James W McClelland7 and Eloise Petrone Brown8, (1)Sandia National Laboratories, Albuquerque, NM, United States, (2)Sandia National Laboratories, Livermore, CA, United States, (3)University of Alaska Fairbanks, Fairbanks, AK, United States, (4)Integral Consulting Inc., Santa Cruz, CA, United States, (5)Woods Hole Research Center, Falmouth, MA, United States, (6)University of Texas at Austin, Austin, TX, United States, (7)University of Texas Marine Science Institute, Port Aransas, TX, United States, (8)University of Alaska Fairbanks, Fairbanks, United States
Recorded Presentation
Abstract:
Accelerating Arctic coastal erosion rates have put critical infrastructure and native communities at risk due to several coincident changes in the Arctic environment: increased wave power due to declining sea ice, increased storm frequency and length of open-water season as well as increased ocean and permafrost temperatures. Although the Arctic comprises one-third of the global coastline, current tools for quantifying permafrost erosion are unable to explain the episodic, storm-driven events. This presentation will highlight results from a numerical modeling and validation campaign. Our ACE (Arctic Coastal Erosion) Model mechanistically couples oceanographic conditions with a terrestrial model to capture the thermo-chemo-mechanical dynamics of erosion.

The ACE Model consists of oceanographic and atmospheric boundary conditions that force a terrestrial permafrost environment in Albany (a multi-physics based finite element model). An oceanographic modeling suite (consisting of Wave Watch III, SWAN, and Delft3D) produces time-dependent surge and run-up boundary conditions for the terrestrial model. In the terrestrial model, a loosely coupled framework unites the mechanical and thermal-chemical aspects of erosion. 3D stress/strain fields develop in response to a plasticity model of the permafrost that is controlled by the frozen water content determined by modeling 3D heat conduction and solid-liquid phase change. This modeling approach enables failure from any allowable deformation (block failure, slumping, etc.).

A 2018 field campaign captured the thermal evolution of a bluff at Drew Point, AK during niche formation and subsequent block failure. This data combined with time-lapse photography, AUV structure for motion surveys, and detailed knowledge of the geomorphological and geophysical properties (strength, thermal, and composition) provide a unique validation study for the ACE Model. Employing 2018 boundary conditions, initial results from this validation case will be presented.

The ACE Model will inform our scientific understanding of coastal erosion processes, contribute to estimates of geochemical and sediment ocean fluxes, and facilitate infrastructure susceptibility assessments.

SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525. SAND2020-7732 C

<< Previous Abstract | Next Abstract >>