RAINDROP: A Framework for Real-Time Holistic Underwater Acoustic Maps

RAINDROP is a framework for real-time holistic underwater acoustic maps, targeting applications in acoustic Digital Twins of the Ocean (DTOs). It takes a top-to-bottom approach, starting with input collection and preparation, followed by simulation setup and execution, and finally post-processing and visualization of results. Its framework nature offers a structure that users can use to couple the latest developments at each step of the solution process. All in a performance-oriented approach that includes embedded parallelization to achieve faster than real-time calculations. In the present work, the latest release of RAINDROP is presented and the coupling/automatization of one of its solvers, KRAKEN, based on normal modes theory, is successfuly verified against the 3D penetrable wedge benchmark. Then, RAINDROP is applied in a practical scenario, to assess the impact of shipping noise during the military NATO exercise REPMUS2024 in Tróia and Sesimbra, in Portugal. The environmental inputs are collected from EMODnet and Copernicus Marine Data Store. AIS data from shipping is farmed from aisstream.io and the equivalent acoustic source of each vessel is modeled using the JOMOPANS-ECHO model. A total of 38 days are simulated, focusing on the 63 Hz frequency, achieving calculations up to 25 times faster than real-time. The results are post-processed using the concept of Level of Onset of Biological Effects (LOBE) by the TG Noise under EU’s Marine Strategy Framework Directive, demonstrating the potential and capabilities of RAINDROP.