3D simulation of coral heat stress in Florida during mass bleaching in 2023

Details

Supervisors

Hanert, Emmanuel ; Dobbelaere, Thomas

Faculty

Faculté des bioingénieurs

Degree label

Master [120] : bioingénieur en sciences et technologies de l'environnement, à finalité spécialisée

Abstract

Over recent decades, ocean warming driven by human activities has led to widespread coral bleaching, representing a major threat to reef ecosystems. In the summer of 2023, Florida's Coral Reef (FCR) experienced a severe bleaching episode, including reefs targeted by the Mission Iconic Reefs (MIR) restoration project. This study aims to replicate the oceanic and thermal conditions during this event using SLIM3D, a 3D baroclinic hydrodynamic model, to better understand the processes at play. By simulating ocean circulation and temperature dynamics, we explore the variability in bleaching severity across Florida’s reefs. Thermal stress accumulation was assessed using the Degree Heating Week (DHW) metric, which was analyzed alongside hydrodynamic outputs to evaluate how ocean features might have mitigated or exacerbated heat exposure. The results reveal strong differences in thermal stress across reef locations, driven by local circulation patterns, vertical mixing, and bathymetric variability. These insights highlight the role of physical ocean processes in shaping bleaching patterns and provide guidance for restoration and management strategies in the context of ongoing climate change.