Validating Velocities in the GeoClaw Tsunami Model Using Observations near Hawaii from the 2011 Tohoku Tsunami

Abstract

The ability to measure, predict, and compute tsunami flow velocities is of importance in risk assessment and hazard mitigation. Substantial damage can be done by high velocity flows, particularly in harbors and bays, even when the wave height is small. Moreover, advancing the study of sediment transport and tsunami deposits depends on the accurate interpretation and modeling of tsunami flow velocities and accelerations. Until recently, few direct measurements of tsunami velocities existed to compare with model results. During the 11 March 2011 Tohoku Tsunami 328 current meters were in place around the Hawaiian Islands, USA, that captured time series of water velocity in 18 locations, in both harbors and deep channels, at a series of depths. We compare several of these velocity records against numerical simulations performed using the GeoClaw numerical tsunami model, based on solving the depth-averaged shallow water equations with adaptive mesh refinement, to confirm that this model can accurately predict velocities at nearshore locations. Model results demonstrate tsunami current velocity is more spatially variable than wave form or height and therefore may be a more sensitive variable for model validation.

Coastal Risk and Water Flow Analysis in Eastern Algeria (Western Mediterranean)

“…This package has been adapted to geophysical problems like solving the nonlinear shallow water equations using a depth-averaged of partial differential equations over bottom topography [16]. In addition to classical tsunami modeling where the purpose was to examine the inundation limits and the water heights in the coast, the Geoclaw software was as well applied to examine the velocity flows that resulted from the March 2011 Tohoku Tsunami [12]. Based on this modeling approach and comparing their results with data observations in the Pacific (gauge, video footage), Arcos and Leveque [12] suggested the tsunami current velocity was a more sensitive variable for model validation.…”

“…In addition to classical tsunami modeling where the purpose was to examine the inundation limits and the water heights in the coast, the Geoclaw software was as well applied to examine the velocity flows that resulted from the March 2011 Tohoku Tsunami [12]. Based on this modeling approach and comparing their results with data observations in the Pacific (gauge, video footage), Arcos and Leveque [12] suggested the tsunami current velocity was a more sensitive variable for model validation. The wave propagation analysis and the depth -averaged system of equations are developed as follows [12,15,16]:…”

“…Based on this modeling approach and comparing their results with data observations in the Pacific (gauge, video footage), Arcos and Leveque [12] suggested the tsunami current velocity was a more sensitive variable for model validation. The wave propagation analysis and the depth -averaged system of equations are developed as follows [12,15,16]:…”

“…Coastal damages or impacts due to water waves are not only related to the height reached by the waves but also to the velocity and the energy that characterize the currents. The knowledge of the tsunami currents flow and velocities provides insights as for the depth at which tsunamis erode and deposit sediments and whether tsunamis can leave submarine records [11,12]. In this paper, our goal is (1) to test and propose a tsunamigenic source that can potentially affect the eastern coast and (2) examine the flow velocities of the induced water waves and currents from the numerical modeling results and the GIS -approach.…”

Introduction to “Tsunami Science: Ten Years After the 2004 Indian Ocean Tsunami. Volume I”

“…Whereas most benchmarks relate to amplitude, runup, and inundation, the study by ARCOS and LEVEQUE (2015) benchmarks the GeoClaw model with respect to current velocities, which have only recently become available in the field. More traditional benchmark exercises are presented by HORRILLO et al (2015) who describe validation of maximum surface amplitude and runup for a number of different tsunami models used to predict inundation for evacuation plans, under the auspices of the U.S. National Tsunami Hazard Mitigation Program.…”