Supplementary file 1_Salt marsh effects on flood hazard metrics under compound coastal flooding.docx

To reduce flood risk, managers and decision makers need a variety of tools to help make informed and scientifically backed decisions. In this sense, the present work uses numerical modeling to simulate tropical cyclone conditions in Mobile Bay, Alabama for the purpose of applying the results to flood risk management strategies.

To those ends, this work focuses on three main contributions: 1) showing the importance of compounding interactions of unsteady fluvial and coastal sources of flooding in accurate hurricane-driven flood hazard assessment; 2) assessing the influence of salt marsh vegetation represented through bottom roughness parameterization on coastal flooding through changes in hydrodynamic energy and depth–velocity conditions; and 3) demonstrating an enhanced safety thresholds framework based on a Composite Flow Intensity indicator to identify flood hazards by combining multiple hydraulic characteristics of flooding.