Naslov
Numerical analysis of a ducted internal gravity-wave package causing an exceptional meteotsunami event in the Adriatic

Autori
Horvath, Kristian ; Telisman Prtenjak, Maja ; Sepic, Jadranka

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, ostalo, znanstveni

Skup
34th International Conference on Alpine Meteorology

Mjesto i datum
Reykjavík, Island, 18.06.2017. - 23.06.2017

Vrsta sudjelovanja
Poster

Vrsta recenzije
Podatak o recenziji nije dostupan

Ključne riječi
numerical simulation, ducted internal gravity wave, Adriatic

Sažetak
Meteotsunamis are long sea surface waves caused by propagating weakly dissipative atmospheric pressure perturbations formed by ducted internal atmospheric gravity waves and/or convection. Several high-amplitude meteotsunamis occurred in the northern Mediterranean countries during a major meteotsunami period from 23-27 June 2014. The largest sea level oscillations were recorded in Vela Luka Bay, Croatia, in the morning of 25 June 2014, where the amplitude of sea level oscillations reached 3 m. Sea level oscillations reaching 2 m were recorded also near Balearic Islands (Spain), Sicily (Italy), and Odessa (Ukraine). The extraordinary spatial dimension of this event shows that meteotsunamis can have a widespread influence that is comparable to other major tsunami-genic mechanisms. The large-scale setting during the meteotsunami period was characterized by an incoming upper-level trough as well as the upper-level jet aloft and warm low-level advection from the African continent. The numerical analysis of the event was carried out using the Weather and Research Forecasting (WRF) mesoscale non-hydrostatic model. The model was configured with four telescoping domains reaching 0.5 km grid spacing over the Adriatic. As inferred by comparison with the ECMWF reanalysis, the model represents well these environmental conditions during the meteotsunami period. The dynamically unstable mid-troposphere with Richardson number smaller than 0.25 capped the warm statically stable air in the lower troposphere. These environmental conditions were favorable for sustaining the internal gravity wave which induced on the Apennines mountain range, as lower layer was statically stable and of sufficient depth. The oscillating surface pressure perturbations at the sea level were also well represented in the simulation. Simulated pressure perturbations were sustained and reached amplitudes of several hPa at the mean sea level, which is of sufficient amplitude to cause a meteotsunami. Finally, we also provide guidance on the model setup requirements necessary for inclusion of numerical weather prediction models in the operational applications of the meteotsunami warning system.

Izvorni jezik
Engleski

Znanstvena područja
Geofizika

POVEZANOST RADA