Atmospheric Forcing Conducive for the Adriatic 25 June 2014 Meteotsunami Event

Abstract

We analyze atmospheric conditions conducive for a meteotsunami event that occurred in the Adriatic on 25 June 2014. This was the most intensive of a series of meteotsunami events which occurred in the Mediterranean and Black Seas during 23-27 June 2014 period. Considerable sea-level oscillations were observed in several eastern Adriatic harbors with a maximum wave height of around 3 m and period of approximately 20 min observed in Vela Luka harbor, Korčula Island, Croatia. Observational analysis of the event utilizes available in situ and remote sensing measurements. For a more detailed insight into the structure of the atmosphere we reproduced the event with the WRF model configured at a sub-kilometer grid spacing. Observational and simulated data both demonstrate that sea-level oscillations in Vela Luka harbor were caused by rapid air-pressure perturbations with amplitudes of up to 4 hPa and a maximal rate of air pressure change above 2 hPa/5 min. Around the time pressure perturbations affected the area, pressure distribution was affected by both con-vection and internal gravity waves, with both wave-CISK and wave duct promoting maintenance of pressure perturbations. This makes the 2014 Adriatic event the first known meteotsunami event in the Mediterranean and Black Seas during which both of these maintenance mechanisms acted jointly. Finally, simulations performed in this event represented meteotsunami-related pressure perturbations at the adequate time and location, which is a step forward in the ability of atmospheric models to assist early warning meteot-sunami systems for the Mediterranean and the Black Seas.