meteotsunamis in the mediterranean sea: rare but destructive extreme sea level events occurring...
TRANSCRIPT
Meteotsunamis in the Mediterranean Sea: rare but destructive extreme sea level events occurring under
specific synoptic conditions
Ivica Vilibić,Ivica Vilibić, Jadranka ŠepićJadranka ŠepićInstitute of Oceanography and Fisheries,Institute of Oceanography and Fisheries,
Split, Croatia, [email protected], Croatia, [email protected]
About meteotsunamis Mediterranean events Connection to the synoptics Some conclusions and perspectives
About meteotsunamis
Sea Level Workshop, Palma, June 2015
Highly resonant phenomenon, very rare occurrence at destructive levels
Šepić et al., Sci. Rep., 2015
About meteotsunamis
Sea Level Workshop, Palma, June 2015
Driven by travelling air pressure disturbances (occasionaly winds)
Vilibić et al., JGR, 2004
Vilibić et al., PAGEOPH, 2008
Mediterranean events
Sea Level Workshop, Palma, June 2015
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šćigašćiga
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Recorded at different Mediterranean locations and basins
Sea Level Workshop, Palma, June 2015
Mediterranean events
Some events: Vela Luka, Croatia, 21 June 1978 6-m waves at the top of the bay
Sea Level Workshop, Palma, June 2015
Some events: Vela Luka, Croatia, 21 June 1978 6-m waves at the top of the bay
Mediterranean events
Vučetić et al., Phys. Chem. Earth, 2009
Sea Level Workshop, Palma, June 2015
Some events: 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.
Mediterranean events
Monserrat et al., NHESS, 2006
Sea Level Workshop, Palma, June 2015
Normally occurring locally at destructive levels, encompassing a few tens of kilometres at most bays of Mali Lošinj and Ist (distanced by 50 km) were not hit by a meteotsunami at the same time
21 June 1978Vela Luka (~6 m)
5 October 1984Ist (~4 m)
27 June 2003Stari Grad (~3.5 m)Mali Ston (currents)
22 August 2007Ist (~4 m)
15 August 2008Mali Lošinj (~3 m)
25 June 2014Vela Luka (~3 m)Stari Grad (~1 m)Vrboska (~1.5 m)Rijeka dubrovačka(~2.5 m, currents)
Mediterranean events
Sea Level Workshop, Palma, June 2015
Mediterranean events Small changes in disturbance speed may end up in several times different wave heights extremely sensitive to resonant conditions
Šepić et al., JGR, 2015
Sea Level Workshop, Palma, June 2015
However, exceptional events may occur over thousand of kilometres Fresh example of 22-27 June 2014 (Šepić et al., 2015) A series of destructive meteotsunamis hit the Mediterranean and Black Seas, following a peculiar atmospheric setting at synoptic scale
Mediterranean events
Šepić et al., Sci. Rep., 2015
Sea Level Workshop, Palma, June 2015
27 June 2014: 2-m wave injured 12 people in Odessa Due to Ukrainian situation, extraordinary explanations flooded the media
Mediterranean events
Sea Level Workshop, Palma, June 2015
The event was connected to a propagating upper troposphere "storm", giving rise to a numerous air pressure disturbances ("boiling atmosphere")
Connection to synoptics
Šepić et al., Sci. Rep., 2015
Sea Level Workshop, Palma, June 2015
A half of moderate and strong meteotsunami events observed on the Balearic Islands are followed by similar events in the Adriatic Sea within 1-2 days
Connection to synoptics
Šepić et al., Phys. Chem. Earth, 2009
Sea Level Workshop, Palma, June 2015
Connection to synoptics
Šepić et al., JGR, 2012
That was already recognized in research of the Balearic and Adriatic meteotsunamis quite useful for creation of a warning system however, only qualitative forecasts may be issued Below: Average SLP, T at 850 hPa and winds at 500 hPa reanalysis fields for 16 events at Rovinj (Adriatic)
Sea Level Workshop, Palma, June 2015
Connection to synopticsConnection to synoptics Confirmed by numerical modelling (atmosphere) Below: air pressure and winds during the 2007 ist meteotsunami as reproduced by the WRF mesoscale model
22 August 2007, 15:12 UTC22 August 2007, 15:12 UTC
Šepić et al., JGR, 2009
Sea Level Workshop, Palma, June 2015
Connection to synopticsConnection to synoptics In general, high-frequency sea level oscillations in the Mediterranean (not only meteotsunamis) may be attributed to synoptic patterns Details may be found on the poster by Šepić et al.
Šepić et al., Prog. Ocean., 2015, under review
Sea Level Workshop, Palma, June 2015
Some conclusions and perspectives
Ocean physics during meteotsunamis well understood and reproduced by ocean models
Atmosphere physics a less well understood, but quite hard to reproduce by numerical models a need for better knowledge on gravity wave generation and propagation in the atmosphere
Connection to a propagating synoptic patterns exists useful for warning systems also useful for assessing long-term and future meteotsunami potential from climate models
Efficient meteotsunami warning systems are still far from operational, but a concept of such a system is developable based on an assessment of synoptic conditions, real-time high-frequency air pressure measurements and remote sensing data (satellites, HF radars)