PhD Dissertation Defense: Jie Gao

The PhD Dissertation Defense of Jie Gao is presented by UNC-CH Department of Marine Sciences and UNC’s Institute of Marine Sciences (IMS). The main location of this event will be in room 222 at IMS in Morehead City, NC. The defense will also be broadcast to conference room 4204 on the 4rd floor of Murray Hall on UNC-CH campus in Chapel Hill, NC. This event will be held on Monday, August 20th at 9:00 PM.

Title:  On the Estimates of Surface Wind Stress for Storm Surge Modeling

Abstract: Surface wind stress is the primary force that drives the upper-ocean circulation and formation of the surface wind waves, especially under Tropical Cyclones (TCs). Current parameterization of surface wind stress in most storm surge models utilize wind speed at 10m height, and a bulk drag coefficient C_d that increases linearly with wind speed. Thus, predictive skills of these models depend crucially on the simulated wind field as well as the surface drag coefficient. In this study, efforts were first made to develop a Generalized Asymmetric Holland Model (GAHM) based on the classic Holland Model for more accurate prediction of surface wind field. Evaluation of GAHM indicated an improvement in consistency between the re-constructed wind field and the input TC advisory data from the National Hurricane Center. Efforts were also made to explore other drag options, including the implementation of two physically-based explicit momentum transfer model for TCs. The primary goal of this study is to evaluate the behaviors of different drag laws under various wind and wave regimes, and to address the uncertainties in storm surges modeling under TCs.