Date of Award

8-22-2025

Document Type

Open Access Thesis

Department

Marine Science

First Advisor

Subrahmanyam Bulusu

Abstract

Mesoscale and submesoscale processes in the Gulf of Mexico (GoM) are fundamental in shaping the region’s physical and biogeochemical ocean dynamics. Advances in high-resolution satellite observations now allow detailed detection of submesoscale (< 25 km radius) and mesoscale eddies and ocean fronts, which drive heat, nutrient, and carbon fluxes. This dissertation integrates two complementary investigations: (1) a comparison of eddy-tracking algorithms: Contour Tracing (CT) and Temperature Thresholding (TT), applied to Optimum Interpolation Sea Surface Temperature (OISST, 1/4°) and Operational Sea Surface Temperature and Ice Analysis (OSTIA, 1/20°) products; and (2) a comparative evaluation of three ocean front detection algorithms: Canny Edge Detection (Canny), the Cayula–Cornillon Algorithm (CCA), and the Belkin–O’Reilly Algorithm (BOA), across multiple satellite-derived parameters, including sea surface temperature (SST), sea surface salinity (SSS), chlorophyll-a (Chl-a), and altimetry-derived absolute dynamic topography (ADT). The eddy-tracking analysis shows that the higher-resolution OSTIA consistently detected more eddies than OISST, with TT performing best during winter when SST gradients were strongest. The front detection analysis, incorporating datasets from the Surface Water and Ocean Topography (SWOT) and Plankton, Aerosol, Cloud, Ocean Ecosystem (PACE) missions, was evaluated under diverse conditions, including flood and drought periods, Loop Current phase changes, and extreme weather events. A machine learning–based Gaussian Mixture Modeling (GMM) approach was also developed, providing a novel framework for dynamic front detection. By benchmarking traditional and machine learning methods, this integrated study identifies optimal algorithm–dataset combinations for resolving submesoscale and mesoscale features in the GoM, with applicability to other regions.

Rights

© 2025, Ethan Cruz

Download

Share

COinS