Affiliation:
1. Georgia Institute of Technology, School of Civil and Environmental Engineering, Savannah Campus, 210 Technology Circle, Savannah, GA 31407-3039
Abstract
Surface water wave measurements in coastal Georgia, USA are considered. The dataset includes non-directional wave energy spectra measured via pressure transducers at two locations; non-directional, wave buoy-derived observations at a third; and directional wave buoy observations at a fourth, closest to shore. Mean depths at the observation sites range from 14 to 44 m. Measurements of non-directional surface wave energy spectra and the resulting bulk wave parameters (height, period) are compared at the four locations to reveal spatial and temporal variations. Directional characteristics of the waves are investigated at the nearshore site. A new, simple definition for directionally bimodal spectra is proposed and applied. The importance of directional bimodality when considering problems that are sensitive to wave direction, such as longshore sediment transport, is demonstrated. Neglect of directional bimodality via the use of a single mean wave direction can lead to significant errors in computation of longshore sediment transport, and potentially even the incorrect sign on computed quantities.