Towards observation- and atmospheric model-based early warning systems for meteotsunami mitigation: A case study of Korea

A traveling air pressure disturbance of several hPa over a short period (5–10 min) can generate tsunami-like waves in coastal areas owing to a multi-resonant mechanism. In recent years, pressure-forced meteotsunamis have been regularly reported over the Korean Peninsula. However, the Korean meteotsunami early warning system does not always provide sufficient lead time. The early warning system comprises two-segmented zones for tracking the intensity and propagation of air pressure disturbances via 89 meteorological stations in the precaution (offshore islands) and warning zones (coastline and inland areas). To address the lead time problem in the current observation-based monitoring system, we used an atmospheric model with a horizontal resolution of 1.5 km, the Korea Meteorological Administration's local data assimilation and prediction system (LDAPS). The ability of the LDAPS to detect air pressure disturbances was tested for a widespread and destructive meteotsunami event that occurred on March 4, 2018. The detection capability of significant air pressure disturbances (>1.5 hPa/10 min) was 67% in the precaution zone, and the propagation pattern (direction, speed, and spatial scale) was reasonably consistent with the monitoring results. Based on LDAPS prediction and the established observation-based monitoring system, monitoring operators can determine the potential meteotsunami risk from the open Yellow Sea beyond the observation system with sufficient lead time. This case study contributes to developing observation- and atmospheric model-based early warning systems for meteotsunami mitigation. An early warning of tsunamigenic disturbances in the Korean Peninsula is expected to be provided with the LDAPS-based modeling system using a high-resolution atmosphere-ocean coupled model shortly.