1. Towards Operational Meteotsunami Early Warning System: the Adriatic Project MESSI
Jadranka Šepić1, Ivica Vilibić1, Clea Denamiel1, Hrvoje Mihanović1, Stipe Muslim1, Martina Tudor2, Damir Ivanković1, Dalibor Jelavić1, Vedrana Kovačević3, Toni Mašće1, Vlado Dadić1, Miro Gačić3, Kristian Horvath2, Sebastian Monserrat4, Alexander Rabinovich5,6, Maja Telišman-Prtenjak7
1 Institute of Oceanography and Fisheries, Split, Croatia
2 Meteorological and Hydrological Service, Zagreb, Croatia
3 Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Sgonico, Italy
4 Department of Physics, University of the Balearic Islands, Palma de Mallorca, Spain
5 P.P. Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia
6 Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney BC, Canada
7 Faculty of Science, University of Zagreb, Zagreb, Croatia
About meteotsunamis
World hotspots
MeEWS architecture
Concluding remarks

2. Project Title: Meteotsunamis, destructive long ocean waves in the tsunami frequency band: from observations and simulations towards a warning system (MESSI)
Principal Investigator: Jadranka Šepić
Co-Principal Investigator: Miro Gačić
Funding: Unity Through Knowledge Fund
Budget: ,11 HRK ( ,11 HRK - UKF)
Project Duration: 15 December 2015 – 14 December 2017
Involved Institution: Institute of Oceanography and Fisheries, (Split, Croatia); Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (Trieste, Italy); Meteorological and Hydrological Service (Zagreb, Croatia); University of the Balearic Islands (Palma de Mallorca, Spain); International Tsunami Research, Inc. (Victoria, BC, Canada)

3. About meteotsunamis
Well, I don’t know how many of you heard about meteotsunamis, destructive long ocean waves in the tsunami frequency band
Ciutadella, Balearic Islands, 15 June 2006
Vela Luka, Adriatic Sea, 21 June 1978
Variance and range of nonseismic high-frequency sea level oscillations
(Vilibić and Šepić, Sci Rep, 2017)
Sea level range over
frequencies at Fremantle, Australia (courtesy of C. Pattiaratchi)

4. About meteotsunamis
Meteorological tsunamis are long oceanic waves that have approximately the same spatial and temporal scales as ordinary tsunamis, and can affect coastal regions in a similar destructive way, but are generated not by underwater earthquakes, volcanic explosions or landslides, but by atmospheric disturbances (hurricanes, frontal passages, squall lines, internal atmospheric waves or by jumps of atmospheric pressure).
Munk [1962]: ‘…The most conspicuous thing about long waves in the open ocean is their absence’
Tsunami and meteotsunami records
(Monserrat et al., NHESS, 2006)
Meteotsunamigenic air pressure disturbances
Sea level record in Split during the 1978 Vela Luka meteotsunami
Tsunami and meteotsunami spectra

5. About meteotsunamis
The story of meteotsunami dynamics in a single graph
Šepić et al., Sci Rep, 2015

6. World hotspots
The science of meteotsunamis evolved during the last decades

7. World hotspots Ciutadella, Spain, 15 June 2006
5-m waves at the top of the bay, strong currents
Tens of sunk and damaged yachts, loss of ~30 MEuro.
Monserrat et al., NHESS, 2006

8. World hotspots 27 June 2014: 2-m wave injured 12 people in Odessa
Due to Ukrainian situation, extraordinary explanations flooded the media

9. World hotspots Panama City, FL Panama City Beach, FL Rovinj, Croatia
Meteotsunami in Gulf od Mexico, 28 March 2014
Panama City, FL
28 March 2014
29 March 2014
Panama City Beach, FL
Wave height ~1.4 m
Period ~10 min
Meteotsunami in Brazil Praya-do-Casino, Brazil, 9 February 2014
Rovinj, Croatia

10. MeEWS architecture
General concept of a meteotsunami warning system (Vilibić et al., Front Mar Sci, 2016)

11. MeEWS architecture
Three modules of the Adriatic pilot meteotsunami early warning system (MeEWS):
(1) synoptic warning module
(2) probabilistic premodelling module
(3) real-time monitoring module
The Adriatic MeEWS flow chart

12. MeEWS architecture Synoptic warning module – 7 days warning in advance
Based on computation of the synoptic meteotsunami index for the meteotsunami hot spot site
meteotsunami index  regression coefficients are obtained through least-squares minimasing on the high-frequency sea level wave height data

13. MeEWS architecture
Probabilistic premodelling module – 2 days warning in advance
The modelling strategy is twofold: (1) the deterministic generation of meteotsunamis is obtained with an operational fully coupled COAWST atmosphere-ocean model at 1 km, while (2) the coastal risk (maximum elevation and currents) is statistically given via the application of the Pseudo Spectral Approximation (PSA) method with the pressure field and the manning’s coefficient defined as a stochastic processes used to force the 6,401 high-resolution ADCIRC simulations

14. MESSI observational network
MeEWS architecture
Real-time monitoring module – an hour warning in advance
Detection of meteotsunamigenic air pressure disturbances – intensity, speed and propagation direction
Then, the best simulation is chosen to estimate the hazard
Split
Brač
Stari Grad
Vis
Svetac
Vela Luka
Sobra
Ortona
Palagruža
Tremiti
Vieste
Ocean-atmospheric
Atmospheric
BPR
MESSI observational network

15. Concluding remarks MESSI project major achievements: Future steps:
Better knowledge on meteotsunami source and propagation, in the Adriatic and worldwide
A step in the observational Adriatic network
Design of the multi-level meteotsunami early warning system
Innovative methodology introduced in geosciences for probabilistic hazard estimates ( PSA method)
Future steps:
Towards operability of the proposed MeEWS
Towards validation of the system
Towards improvements of the system