“BOTTOM STRESS TIME-HISTORY” IN LINEARIZED EQUATIONS OF MOTION FOR STORM SURGES

Abstract

A transient Ekman's transport equation, in which bottom stress is formed as a convoluted integral in terms of surface stress and surface slope, and a continuity equation are used as predictors to compute storm surges in a model basin. Driving forces in the basin are analytically computed, using a model storm to represent actual meteorological conditions. A coastal boundary condition that relates surface slope to surface stress is developed by balancing slope and drift transports normal to a vertical wall. At interior grid points of the basin, sea-surface heights are computed by numerical means, using the prediction equations. These sea-surface heights are then extrapolated to the coast to agree with the coastal surface slope given by the boundary condition. Coastal storm surges computed in this manner are compared with observed surges to test the model developed in this study.