Application of Data Assimilation for Spectral Wave Model in Coastal Regions of South Korea

Abstract

The primary factor determining the accuracy of wave simulation is the accuracy of the wind data, which represents the main force of wave generation. Its accuracy also depends on the optimality of parameters related to the growth, dissipation of wave energy and nonlinear energy transfer between wave components. Wave models have limitations due to errors of wind fields and a lack of understanding of wave dynamics such as white capping dissipation, wave-bottom interaction processes and long-term wave propagation. This paper investigates the performance of a wave model based on WAVEWATCH III (WW3) version 6.07 equipped with spectral wave data assimilation using the optimal interpolation (OI) method, which updates the spectral wave energy of the model by assimilating the observed significant wave height. Data assimilation was applied for the coastal region of Korea using near real-time global satellite wave observation data provided by the Copernicus Marine Environment Monitoring Service (CMEMS) and the buoy data of the Korea Meteorological Administration (KMA). The verification of the model was done by comparing simulated results with observations by KMA buoys, which suggests the successful application of the data assimilation to improve the model accuracy.