Numerical wave modeling with a Boussinesq-type model against insitu and LIDAR recorded field data on a sandy beach at Duck, NC

Accurate predictions of wave runup are critical to estimating storm impacts to coastal beach and dune systems. While many simplified parameterizations exist for estimating wave runup from offshore wave parameters, their accuracy may be reduced on intermediate beaches where surf-zone wave transformation over sandbars can play an important role in modulating the amount and distribution of wave energy reaching the shoreline. As a result, improved tools to simulate wave runup are needed to ensure accurate design of engineered beach-dune systems for a region’s wave and storm climate. The purpose of this work is to evaluate the application of Boussinesq-type wave models (e.g. FUNWAVE) for simulating wave runup at open-coast intermediate beaches, and to identify model sensitivities to input parameters. Observations of waves in the surf and swash zone, mean water levels, and swash-zone sand levels were acquired on a sandy beach at the U.S. Army Engineer Research and Development Center’s Field Resesarch Facility in Duck, NC using a combination of in situ pressure gauges and spatially dense LIDAR measurements. A variety of model parameters were explored to determine the best model setup for estimating wave runup and surf-zone waves in a range of wave conditions, including varying the frequency resolution of input spectra (with number of frequency bins spanning from 29 to 3600). Model runs were completed on the Department of Defense High Performance Computing Center, which allowed for increased testing of the parameters space.