Data and numerical analysis of astronomic tides, wind‐waves, and hurricane storm surge along the northern Gulf of Mexico

Abstract

AbstractThe northern Gulf of Mexico (NGOM) is a unique geophysical setting for complex tropical storm‐induced hydrodynamic processes that occur across a variety of spatial and temporal scales. Each hurricane includes its own distinctive characteristics and can cause unique and devastating storm surge when it strikes within the intricate geometric setting of the NGOM. While a number of studies have explored hurricane storm surge in the NGOM, few have attempted to describe storm surge and coastal inundation using observed data in conjunction with a single large‐domain high‐resolution numerical model. To better understand the oceanic and nearshore response to these tropical cyclones, we provide a detailed assessment, based on field measurements and numerical simulation, of the evolution of wind waves, water levels, and currents for Hurricanes Ivan (2004), Dennis (2005), Katrina (2005), and Isaac (2012), with focus on Mississippi, Alabama, and the Florida Panhandle coasts. The developed NGOM3 computational model describes the hydraulic connectivity among the various inlet and bay systems, Gulf Intracoastal Waterway, coastal rivers and adjacent marsh, and built infrastructure along the coastal floodplain. The outcome is a better understanding of the storm surge generating mechanisms and interactions among hurricane characteristics and the NGOM's geophysical configuration. The numerical analysis and observed data explain the ∼2 m/s hurricane‐induced geostrophic currents across the continental shelf, a 6 m/s outflow current during Ivan, the hurricane‐induced coastal Kelvin wave along the shelf, and for the first time a wealth of measured data and a detailed numerical simulation was performed and was presented for Isaac.