Research Seminar – John Ratcliff

The UNC-CH Department of Marine Sciences and UNC’s Institute of Marine Sciences (IMS) presents a research seminar from graduate student, John Ratcliff. This event will be held on Monday, December 7th, at 12:00 pm. The physical location of this event will be in seminar room 222 at IMS in Morehead City, NC. However this seminar is remote only and can be viewed online via Zoom (Meeting ID: 915 9873 5283).

Seminar Title: Analysis of Wind and Storm Surge from Hurricane Florence Using ADCIRC

Abstract: Several anthropogenic effects are contributing to an escalating risk of coastal flooding. These factors will most likely enhance the severity of hurricane induced storm surge and accurately predicting these events is increasingly important for public safety, port navigation, and guidance in coastal planning. Hydrodynamic models have become a valuable tool for prediction and study of water movement along our coasts and in our estuaries. However, the skill in storm surge and flooding prediction is limited by the accuracy of the meteorological inputs that are used as forcing for tropical cyclone events. In this study, a thorough analysis was performed on the wind and storm surge response that took place during Hurricane Florence in September of 2018 using the ADCIRC coastal hydrodynamic model. Multiple meteorological products were employed as forcing to ADCIRC, including two reanalysis datasets along with ADCIRC’s internal tropical cyclone model that uses storm parameters specified by data from the National Hurricane Center. Validation of model accuracy has been conducted based on comparison with numerous wind and water level observations captured throughout coastal North Carolina. Notable results highlight the difficulties in resolving the steep wind gradient of the storm’s eye using gridded, dynamic wind models and the resulting impact on maximum storm surge prediction. Results along the southern North Carolina coast show that accurately recreating rapidly changing wind directions are crucial for correct surge predictions. ADCIRC’s algorithms for imposing the effects of land roughness on horizontal 10-meter winds have been carefully examined and modifications proposed to the land effects that improved predictions for this storm.