Variations of storm surge caused by shallow water depths and extreme tidal ranges

A few studies have analyzed the characteristics of storm surge because of the difficulties involved in laboratory experiments and field observations, and little is known about the variations of storm surge on different tidal ranges. This study analyzes the influence of water depth and astronomical tide upon storm surge by using storms virtually generated by PBL-ADCIRC, a verified numerical analysis program. To examine the potential errors of the conventional method which estimates the maximum water level by linear superposition of tides and storm surge, we conducted our simulations in the seas around the Korean Peninsula which have quite different water depths and tides. Storm surge was found to be in an inverse proportion to water depth and tide. The simulation results confirmed that the coupling of storm surge and tides is essential in the coast of small water depth and large tides.

► We analyze the characteristics of storm surge using a verified numerical model.
► Storm surge is strongly influenced by tides at shallow water.
► Strength of storm surge is increased at spring tide and vice versa at neap tide.
► Conventional linear summation has weakness at shallow water with extreme tide.
► Tide is necessary for simulation of storm surge at shallow water with extreme tide.