We set up a 2D model of the Central Atlantic Coast of Florida, USA, in the openTELEMAC software.  This model encloses the coast between Port St. Lucie and Cape Canaveral.  It includes the Atlantic Ocean waters between the shoreline and ~40 km offshore. Also, it includes the Indian River and Banana River lagoons; as well as the tidal inlets of Port St. Lucie, Fort Pierce and Sebastian connecting those lagoons to the shoreface (Fig. 1).

The model provides a link between global scale hydrodynamics and atmospheric conditions with local currents, waves and sediment processes.  This is achieved by forcing boundary conditions from global datasets (HYCOM and ERA5 models), and simulating its time-space evolution over a finely resolved mesh of Central Atlantic Coast of Florida (Fig. 1).

Simulations proved that the model is able to reproduce measured hydrodynamics of the coast of Fort Pierce throughout 2016, and during Hurricane Matthew (Fig. 2).  These simulations also hindcast the evolution of the sediment bed throughout 2016 (Fig. 3), and are a suitable basis to perform long term UXO mobilization studies through the newly developed UXOmob modelling suite.

The DRAMBUIE 2.0 model has already demonstrated the capability to predict UXO (unexploded ordnance) burial due to wave and current action. In its latest iteration, two fundamental components—the equilibrium burial model and the time evolution model—were refined for enhanced accuracy. Given the critical role of the time evolution model, this component received a significant upgrade through the incorporation of empirical equations proposed by Friedrichs et al. (2018). Using foundational work by Soulsby (1995), a time-stepping approach was developed to model scour burial over time under unsteady flow conditions, following principles from Whitehouse (1998).

The improved burial prediction approach was implemented in MATLAB R2023a, integrating the equilibrium burial model from Friedrichs et al. (2018) with Whitehouse's (1998) time evolution model for dynamic flow conditions. This refined tool, DRAMBUIE 3.0, was tested by modeling the burial depths of realistic UXO shapes during the impact of Hurricane Matthew. For this simulation, DRAMBUIE 3.0 was driven by hydro-morphodynamic data provided by Escobar et al. (2023), assuming UXOs to be cylindrical with a diameter of 0.155 meters.

The results showed that the greatest burial depths were predicted at a sandbar (Fig.1, left column), followed by the lower shoreface (right column). The UXOs at the sandbar experienced significant burial within the 10 hours leading up to the storm, whereas burial at the lower shoreface mostly occurred after the storm had passed. This data provides valuable insight into the sediment dynamics and burial risks associated with UXOs under extreme weather events, contributing to improved management of munitions-contaminated seabed areas.

The software design illustrated in the upper-left image showcases a robust architecture centered around a Core and a Plugin System. The Core is divided into three key components: Input, Simulation, and Output, each fulfilling specific roles within the software.

The Input component acts as an entry point for external data sources and defines interfaces that are implemented in the Plugin System. These interfaces serve as essential connectors, enabling smooth interaction between the Core and various data formats like netCDF and CSV. This modular approach enhances flexibility and simplifies the integration of diverse data sources.

The Simulation component connects to the Plugin System through three interfaces: Wave Model, Mobilization Model, and Burial Model. Each of these interfaces is implemented by specialized computational models, allowing users to integrate different models as needed. This design supports easy addition of new simulation models, promoting scalability and adaptability.

The Output component can simultaneously connect to multiple plugins implementing the Output Interface, allowing for parallel use of various output formats, including time series, spatial data storage, and spatiotemporal results. This flexibility ensures the software’s ability to meet diverse output requirements effectively.

Key benefits of this design include the use of interfaces to support loose coupling between components, making the software easier to maintain and expand. The Plugin System allows for the dynamic addition of new functionality without modifying the Core, ensuring scalability and adaptability to changing needs. This modular approach also enhances reusability, reducing development time and effort, while supporting integration with various data sources and output formats. Additionally, Data Providers and Data Sinks within the Plugin System enable efficient data handling, improving the software’s overall performance and usability.

A user-friendly graphical interface empowers users to easily select their preferred data sources, simulation models, and output formats.

The simulations are prepared for six selected objects. The current state of the algorithms, considering only monochromatic waves, is used to compute the burial and mobilization of the 500 lbs General Purpose Bomb. The plots on the right show the state of this object following Hurricane Matthew around Fort Pierce, Florida. The potential mobilization analysis (upper image) shows a lot of activity for the 500 lbs General Purpose Bomb. This is mainly caused by sediment erosion and thus re-exposure of the object. Furthermore the application of monochromatic waves with the wave period being the peak wave period and the wave height being the maximum wave height from the statistical values, tends to strongly overpredict mobilization. In the future, a realistic wave distribution will be considered. The lower image shows the final burial state with regions of complete burial, caused by selfburial and morphodynamics, and regions with lower burial depth. Comparing this result with the morphodynamics, regions of pure self-burial and regions of re-exposure can be found.