Sandia National Labs FY20 LDRD Annual Report

FY20 ANNUAL REPORT

A predictive model for Arctic coastal erosion. Current tools for quantifying permafrost erosion are unable to explain the episodic, storm-driven erosion events; however, the treatment of transient erosion events can be enabled by mechanistically coupling oceanographic predictions with a terrestrial model to capture the thermo-mechanical dynamics of erosion. The Arctic Coastal Erosion (ACE) model consists of oceanographic and atmospheric boundary conditions that force a coastal terrestrial permafrost environment in Albany. This modeling approach enables failure from any allowable deformation. Extensive experimental work underpins the ACE model development, including field campaigns to measure in-situ ocean and erosion processes, strength properties derived from thermally-driven geomechanical experiments, and extensive physical composition and geochemical analyses. This work, done in collaboration with the University of Texas at Austin, offers the most comprehensive and physically grounded treatment of Arctic coastal erosion available in literature. The ACE model and experimental results can inform scientific understanding of coastal erosion processes, contribute to estimates of geochemical and sediment land-to-ocean fluxes, and facilitate infrastructure susceptibility assessments. (PI: Diana Bull)

A Sandia researcher holds up a core sample of thermokarst-cave ice with vertical frost cracks; this indicates thawing degree days occurred in this Arctic area.

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LABORATORY DIRECTED RESEARCH & DEVELOPMENT