IHCantabria researchers lead a study on regional modeling of hurricane-induced extreme sea levels

A team of researchers from the Environmental Hydraulics Institute of the Universidad de Cantabria (IHCantabria) has made an important advance in the understanding and prediction of storm surges caused by hurricanes in the tropical Atlantic. The study, entitled “Regional modelling of extreme sea levels induced by hurricanes” was recently published in the scientific journal Natural Hazards and Earth System Sciences.

The work has been developed by the following IHCantabria researchers: Alisée Chaigneau, Melisa Menéndez, Marta Ramírez Pérez and Alexandra Toimil. Their study focuses on the factors that affect the performance of numerical models, such as wind action according to its source of origin, the interaction with the astronomical tide on the coast, or the contribution of ocean circulation due to variations in temperature and salinity, among others─ to simulate extreme sea levels during hurricanes. These phenomena represent a significant threat to coastal areas due to sea level rise associated with low atmospheric pressure and strong winds blowing offshore. These extreme sea levels are the result of storm surges. As an example, in the Gulf of Mexico region, values of 4 meters of sea level rise have been estimated due to Hurricane Matthew (2016).

The study evaluates two numerical models widely used by the scientific community for the simulation of sea level changes: the US-based model ADCIRC(Advanced Circulation model for oceanic, coastal and estuarine waters) and the model developed by the European community NEMO (Nucleus for European Modelling of the Ocean). The evaluation was carried out using simulations of four historical hurricanes that affected the Caribbean region and the Gulf of Mexico: Wilma (2005), Matthew (2016), Irma (2017) and Maria (2017). The results, compared with data recorded onshore by tide gauges, showed that both models are able to successfully simulate sea level variations caused by these extreme events, although their performance varies depending on the atmospheric and oceanic forcings used.

Among the main conclusions is that, in the study area, the wind fields from the most current reanalysis products (ERA5) provide better estimates than the parametric wind models, frequently used in the state of the art. Also, including three-dimensional processes such as temperature and salinity variations, which generate ocean circulation, improve the estimates of sea level changes in certain regions, such as the southeastern Florida peninsula (USA).

The findings of this study not only improve the understanding of the physical mechanisms behind storm surges, but also advance the assessment of severe coastal impacts, such as hurricane flooding.

The full content of the scientific paper entitled “Regional modelling of extreme sea levels induced by hurricanes” is available through the following link: https://nhess.copernicus.org/articles/24/4109/2024/