Publications

We were interested in linking the onshore inundation to coastal boulder transport. During Winter 2023/24 on Inishmaan, Ireland, we used the following methods: drone and RTK GNSS surveys, accelerometers inside boulders, Apple Airtags, winching boulders directly, in-situ measured frictional coefficients, detailed boulder shapes from field iPhone lidar scans (post-processed), and pressure sensor deployment for onshore depths. 

We then used the field evidence to improve an Initiation of Motion model for the coastal boulder transport for arbitrary shapes (i.e., just plug in the 3D volumes, and 2D drag and lift areas calculated from the lidar) and for boulders moving under partial submergence. We test the newly derived IoM relations and calculated inundation velocities using Froude numbers, field evidence, and motion records. We found most inferred Froude numbers exceeded unity, which is different than published assumptions for storm wave-driven boulder transport. All boulder motion occurred during times of measured inundation from named storms, and almost always near high tide.

Spero, H.R., Berke, M., Berryhill, J., Bourke, M., Cullen, N., Herterich, J., and Kennedy, A.,  “Onshore Inundation and Coastal Boulder Initiation of Motion at Inishmaan, Ireland” (2026). Geomorphology. DOI: https://doi.org/10.1016/j.geomorph.2026.110197.

Collaborators: Trinity College Dublin, Texas A&M Univ.-Corpus Christi, Dublin City University, University College Dublin, University of Notre Dame. Funding: Naughton (AK), NHERI RAPID (HS), GLOBES (HS), NSF GRFP (HS), NSF CREST (MS)

Description: Observing storm-driven coastal boulder transport across multiple sites of varying exposure on Inishmaan, Ireland. Using a wide variety of field methods, including drone and RTK GNSS surveys, accelerometer sensor deployments inside boulders, winching boulders from ridge to platform edge before winter storms, and traditional field methods as well. In this work, we could link that (1) boulders do move annually, (2) when they move (within 10-minutes, using accelerometers), (3) the degree of orientation change - i.e., sliding vs. rolling, (4) and linking that to hydrodynamic conditions at that time using the nearby Inishmore tide gauge and the offshore M2 and M4 wave buoys. 

Collaborators: Trinity College Dublin, Texas A&M Univ.-Corpus Christi, Dublin City University, University College Dublin, University of Notre Dame. Funding: Naughton (AK), NSF GRFP (HS), NSF CREST (MS).

Summary: Communicating the scale of dam failure risks to the general public and decision-makers is imperative. Two-dimensional (2D) dam failure hydraulic models inform owners and floodplain managers of flood regimes but have limitations when shared with non-specialists. This study addresses these limitations by constructing a 3D Virtual Reality (VR) environment to display the 1976 Teton Dam disaster case study using a pipeline composed of (1) 2D hydraulic model data (extrapolated into 3D), (2) a 3D reconstructed dam, and (3) a terrain model processed from UAS (Uncrewed Aerial System) imagery using Structure from Motion photogrammetry. This study validates the VR environment pipeline on the Oculus Quest 2 VR Headset with the criteria: immersion fidelity, movement, immersive soundscape, and agreement with historical observations and terrain. 

Collaborators: Boise State VizLab (Steve Cutchin, Rezvan J. Iker V., Kenny M.), Donna Calhoun (Mathematics). Funding: URCA (HS)

Summary: Validating GeoClaw software (two-dimensional (2D) dam failure hydraulic model) against leading industry-standard software, HEC-RAS. We were interested in examining the downstream effects of dam failure and comparing instantaneous breaches with time-dependent breaches, as well as their impact on flood wave arrival times, levels, and other metrics. We were also interested in comparing the modeled findings with historical archives and anecdotes of high-water marks.

Collaborators: Donna Calhoun (Mathematics) - mentor. Funding: NSF (DC).

Spero, Hannah R., "Validating Geoclaw for Simulating Teton Dam Failure by Comparison with HEC-RAS Results and Historical Observations" (2021). Geosciences Undergraduate Theses. 1. https://scholarworks.boisestate.edu/geo_undergrad_theses/1