Air–Sea Dynamics Behind Meteotsunamis: A Decade of Operational Forecasting with the Balearic Islands Rissaga Forecasting System

Meteotsunamis are high-frequency sea level oscillations triggered by atmospheric disturbances, originating from complex atmosphere-ocean coupling mechanisms. Unlike seismic tsunamis, these events are driven by meteorological factors—such as pressure jumps or atmospheric gravity waves—that resonate with local coastal dynamics. Meteotsunamis can reach amplitudes of several meters, posing significant risks to coastal infrastructure, marine operations, and public safety. They can reach extreme amplitudes, imposing hazardous conditions in certain regions. One of the most affected locations in the western Mediterranean is the Ciutadella harbor in the Balearic Islands, a well-known meteotsunami hotspot. There, unique coastal geometries—such as the narrow inlet and the shallow continental shelf—create ideal conditions for resonance and amplification. In this setting, annual events exceeding 1 meter in amplitude are routinely observed, while historical extremes have reached 3–4 meters, causing substantial socio-economic impacts.

To mitigate these risks, extensive research efforts have focused on both understanding the generation mechanisms of meteotsunamis and developing reliable forecasting tools. This led to the implementation of the Balearic RIssaga Forecasting System (BRIFS), an operational early warning system developed by ICTS SOCIB. BRIFS has been providing daily forecasts over the past decade by and contributing to official warnings. The system uses high-resolution nested atmosphere-ocean models to predict high-frequency air pressure anomalies and the corresponding sea-level response in Ciutadella harbor up to 48 hours in advance. The WRF model simulates atmospheric conditions at 4 km resolution and 1-minute intervals, while the ROMS ocean model—configured with nested domains—resolves the coastal sea level response.

In this study, we analyze the coupled atmospheric-oceanic processes responsible for significant meteotsunami events recorded in the Balearic Islands over the past ten years. We also assess BRIFS performance by comparing forecasts to in-situ observations from a regional monitoring network, which captures high-frequency pressure and sea level signals across the Balearic Islands. Furthermore, we provide insights into the challenges and potential improvements for the prediction of meteotsunamis to support early warning decision support in the framework of Digital Twins of the ocean.