Meteorological Tsunami of 19 March 2017 in the Persian Gulf: Observations and Analyses

Abstract

On 19 March 2017, destructive tsunami-like waves impacted the northeast shore of the Persian Gulf (PG). The maximum surveyed runup of about 3 m was observed at Dayyer in southern Iran, where damaging waves inundated the land for a distance of * 1 km and resulted in the deaths of five people. Because the PG has always been considered safe from extreme oceanic waves, the event was totally unexpected. In this study, we examined sea level data from 12 stations across the PG and a variety of meteorological information, including satellite imagery, high-altitude isohypse maps and high-resolution air pressure records from 47 instruments along the PG. Our results show that the event was very local, with recorded maximum trough-to-crest wave heights of 197 cm at Dayyer and 234 cm at Asaluyeh, nearfield cities in Iran located * 80 km apart. The dominant wave periods were in the range of 15-20 min. At all distant tide gauges, the observed wave heights were \ 35 cm. No earthquakes or landslides were evident at the time of the event. On the other hand, atmospheric processes during 18-22 March were very active and 10 distinctive tsunamigenic air pressure disturbances were observed propagating over the PG, suggesting that the event of 19 March 2017 was a ''meteorological tsunami''. Atmospheric conditions over the PG were highly favourable for the generation of meteotsunamis and very similar to those that caused a chain of strong meteotsunamis in the Mediterranean and Black Sea regions during 23-27 June 2014. Based on the 500 hPa wind, we evaluated that the disturbances had propagation speeds of 21-38 m/s, with the disturbance at Dayyer having a speed of * 26 m/s toward 77°T rue. The Froude number, Fr (estimated as the ratio of the air disturbance speed to the long wave speed), on 19 March 2017 in the Dayyer/Asaluyeh region was close to resonance, Fr * 0.9 to 1.1, which is highly favourable for meteotsunami generation. Our findings indicate that the Dayyer/Asaluyeh area is a ''hot spot'' that is highly vulnerable to extreme, weather-induced tsunami-like waves.

Weather radar and ancillary observations of the convective system causing the northern Persian Gulf meteotsunami on 19 March 2017

“…As a geological origin of the event was discarded, a meteorological origin was also investigated by the authors with realistic numerical ocean simulations; however, due to unsatisfactory bathymetric data and meteorological forcing, the simulated extreme sea levels, even though qualitatively comparable to the observations, greatly underestimated the real impact of the waves. Further support for the meteorological origin of the event was provided by Heidarzadeh et al (2020). Based on satellite imagery, atmospheric reanalysis products and in situ measurements, including sea level and high-resolution air pressure data recorded along the south of the Persian Gulf, resemblance between the observed high-frequency air pressure and sea level oscillations as well as synoptic patterns similar to those associated with the Mediterranean meteotsunamis (Šepić et al 2015a) were found.…”

“…In the Persian Gulf, weather radar observations were not previously documented by Salaree et al (2018) and Heidarzadeh et al (2020) during the 2017 Dayyer event, and the mesoscale properties of the atmospheric disturbances that caused the destructive waves were not investigated. In this study, the meteotsunamigenic origin of the waves observed along the Dayyer coastline is studied in detail with 15-min time slices of weather radar observations from Bushehr; these observations are precise enough to document the propagation of the squall line and the associated convective cell and are combined with previously unpublished ground data and observations.…”

Special issue on the global perspective on meteotsunami science: editorial

“…Smirnov et al (2021) examined spatial structure of eigenmodes in individual bays of the Peter the Great Gulf located in the Sea of Japan, demonstrating that resonant amplification of arriving waves in these bays can destructively multiply the height of both tsunamis and meteotsunamis. Finally, Kazeminezhad et al (2021) completed the earlier studies of the 2017 Dayyer event (Salaree et al 2018;Heidarzadeh et al 2020) and documented weather radar and ancillary atmospheric observations during the catastrophic meteotsunami in the Persian Gulf that killed 5 people and injured 22, focusing on a narrow and intense squall line that was detected in the radar images throughout its propagation over the sea before hitting the coastline.…”

“…In some bays, the meteotsunami waves have been recorded with heights of several metres and associated currents of several knots, which may pose a particular threat to low-tidal regions, like the Mediterranean and Black seas (Vilibić et al 2021) and the Great Lakes (Bechle et al 2016), where the coastal infrastructure is not adapted to such strong sea-level oscillations. A number of catastrophic meteotsunamis have been recorded in modern times: (1) The Great Lakes, USA, in 1954, killing 7 people in Chicago (Ewing et al 1954), (2) Vela Luka, Croatia, in 1978, resulting in US$7 million in damage at that time (Vučetić et al 2009), (3) Nagasaki Bay, Japan, in 1979, killing 3 people and flooding coastal cities (Hibiya and Kajiura 1982), (4) Ciutadella in the Balearic Islands, Spain, in 1984 and2006, sinking tens of yachts and boats and causing of tens of millions of euros in damage (Jansà and Ramis 2021), (5) Daytona Beach, Florida, USA, in 1992, causing at least 75 injuries and damaging several dozen vehicles on the beach (Churchill et al 1995), (6) the catastrophic 2007 event in Mostaganem (Algeria) responsible for the death of 12 people (Okal 2021), (7) the catastrophic meteotsunamis that affected the north Persian Gulf coastline, Iran, causing the death of 5 people and injuring 22 (Salaree et al 2018;Heidarzadeh et al 2020;Kazeminezhad et al 2021), and several others. Being so destructive, the phenomenon intimidated the inhabitants to such an extent that they gave them particular local names: "abiki" and "yota" in Japan, "rissaga" or "resaca" in Spain, "šćiga" or "štiga" in Croatia, "marrubbio" or "marrobbio" in Sicily, "milghuba" in Malta, "Seebär" in Baltic countries, and more (Monserrat et al 2006;Rabinovich 2009).…”

Combined hazard of typhoon-generated meteorological tsunamis and storm surges along the coast of Japan

“…A number of devastating meteotsunami events occurred in various parts of world oceans, including the coasts of North and South America, SE Asia, South Africa and Australia, as well as the Great Lakes (Pattiaratchi and Wijeratne 2015;Rabinovich 2020). The 3.5-m Dayyer meteotsunami of 19 March 2017 killed five people and severely destructed local infrastructure on the coast of the Persian Gulf (Salaree et al 2018;Heidarzadeh et al 2020a). In bays, inlets, harbours and lakes, meteotsunamis, as well as seismically generated tsunamis, have the same character of eigen oscillations of the corresponding basins, i.e.…”