Storm surges pose significant threats to coastal communities, yet negative surges are not as
well understood as positive surges. In this study, idealized experiments of a tropical cyclone
forcing a 3D ocean model are conducted to investigate the asymmetry of positive and
negative surges. Negative surges are larger in magnitude and extend further across the
coastline than positive surges. While positive surges are driven by wind blowing onshore,
negative surges are largely dominated by alongshore winds, with horizontal divergence as the
main mechanism. This asymmetry also increases with decreasing depth and increasing
latitude.