School of Civil and Environmental Engineering 

Ph.D. Thesis Defense Announcement 

Drivers of Coastal Sea Level and Flooding along the East Coast of the United States

By 

Kyungmin Park

Advisor: 

Dr. Emanuele Di Lorenzo

Committee Members: 

Dr. Kevin A. Haas (CEE); Dr. Alexander Robel (EAS); Dr. Joel Kostka (BIOS); Dr. Tal Ezer (ODU); Dr. Nadia Pinardi (UB)

Date & Time: 

Monday, November 21, 2022, 1:00 pm

Coastal cities and communities are on the frontline as sea-level rise induced by climate change expands the oceans and re-draws the maps of the coastline. Despite the emerging threats of sea-level rise and flooding, the current water level observational networks and the modeling approaches for the U.S. East Coast are inadequate to resolve the combined effects of watershed loading, the spatiotemporal variations of the extreme water level, and the compound flooding at the scale of rivers, tributaries, creeks, and City’s block during hurricane events. These limitations pose challenges for understanding, predicting, and mitigating the regional and city-scale impacts of climate extremes and flooding on coastal communities. They also imply that coastal decision-makers and planners are not equipped with adequate tools to inform coastal protection and management strategies. The main goals of this thesis are to develop large-scale, three-dimensional, high-resolution coastal models to overcome the limitations of existing technologies and use them to diagnose the role of extreme water level drivers along the East Coast of the United States. Accordingly, chapter 1 introduces the drivers of extreme water levels along the U.S. East Coast. In chapter 2, I present a new modeling system that has been implemented to deliver a 3-day forecast system in Chatham County (GA). This system that has been operational since 2019 is currently being used by the Chatham Emergency Management Agency and the City of Savannah to design new emergency protocols and advance a city-wide resilience planning process. In Chapter 3 I use this modeling system to conduct a series of hurricane hindcast and sensitivity experiments to examine the relative roles of extreme water level drivers during major coastal storms and quantify its contributions to the spatial and temporal patterns of extreme water levels. Specifically, this chapter investigates the important oceanic responses to hurricane forcing (e.g., change in Gulf Stream, Ekman transport and Coastally Trapped Waves) compared to the local atmospheric wind and pressure forcing on the U.S. southeast coast. In Chapter 4, I expand the numerical modeling capability and domain over the entire U.S. East Coast to examine the persistent high water level following a hurricane. I find that baroclinic drivers linked to an oceanic adjustment cause the abnormal increase in water levels even after hurricanes have dissipated, which is twice as high as the sea-level rise in 100 years (≈34 cm) on the Georgia coast. In Chapter 5, I conclude the works by discussing how these new insights into the multiple drivers of abnormal water levels, both during and after hurricane events, fill critical knowledge gaps and data needs necessary to inform best practices to scientists, engineers and policymakers.