1. Scenario based tsunami wave height estimation towards hazard evaluation for the Hellenic coastline and examples of extreme
inundation zones in South Aegean
Nikolaos S. MELIS, Aggeliki BARBEROPOULOU, Elias FRENTZOS and Vassilios KRASSANAKIS
National Observatory of Athens, Institute of Geodynamics, Greece
ABSTRACT
A scenario based methodology for tsunami hazard assessment is used, by incorporating earthquake sources with the
potential to produce extreme tsunamis (measured through their capacity to cause maximum wave height and inundation
extent).
In the present study we follow a two phase approach. In the first phase, existing earthquake hazard zoning in the greater
Aegean region is used to derive representative maximum expected earthquake magnitude events, with realistic
seismotectonic source characteristics, and of greatest tsunamigenic potential within each zone. By stacking the scenario
produced maximum wave heights a global maximum map is constructed for the entire Hellenic coastline, corresponding to
all expected extreme offshore earthquake sources. Further evaluation of the produced coastline categories based on the
maximum expected wave heights emphasizes the tsunami hazard in selected coastal zones with important functions (i.e.
touristic crowded zones, industrial zones, airports, power plants etc). Owing to its proximity to the Hellenic Arc, many urban
centres and being a popular tourist destination, Crete Island and the South Aegean region are given a top priority to define
extreme inundation zoning.
In the second phase, a set of four large coastal cities (Kalamata, Chania, Heraklion and Rethymno), important for tsunami
hazard, due i.e. to the crowded beaches during the summer season or industrial facilities, are explored towards
preparedness and resilience for tsunami hazard in Greece.
To simulate tsunamis in the Aegean region (generation, propagation and runup) the MOST – ComMIT NOAA code was used.
High resolution DEMs for bathymetry and topography were joined via an interface, specifically developed for the inundation
maps in this study and with similar products in mind. For the examples explored in the present study, we used 5m resolution
for the topography and 30m resolution for the bathymetry, respectively. Although this study can be considered as
preliminary, it can also form the basis to further develop a scenario based inundation model database that can be used as an
operational tool, for fast assessing tsunami prone zones during a real tsunami crisis.
Geophysical Research Abstracts, Vol. 18, EGU2016-11285-1, 2016, EGU General Assembly 2016
© Author(s) 2016. CC Attribution 3.0 License.
D.103 - Hall D - NH4.1/OS4.7/SM3.4 - Fri, 22 Apr, 10:30–12:00
This work has been completed
under the project KRIPIS – ASPIDA
Maximum Magnitude expected following Papaioannou & Papazachos (2000)
zoning in Greece and selection of scenarios from the JRC Database at NOA
(a) (b) Maximum Magnitude expected in 1000 years period ,following Vamvakaris et al.
(2016) zoning in Greece and selection of scenarios from the JRC Database at NOA
PHASE 1 Methodology
Following two earthquake hazard studies for Greece: (a) Papaioannou and
Papazachos (2000) and (b) Vamvakaris et al. (2016), we computed and assigned the
maximum earthquake magnitude for each of their defined hazard zones, for both
considered cases respectively. Then, we selected accordingly, tsunami propagation
scenarios from the JRC-IPSC developed Database (Annunziato 2007), which has
been updated and is used at NOA for operational purposes under the HL-NTWC
routine operation. Each selected scenario is represented by a map of the maximum
expected tsunami wave height near the coastline. All the resulted maps were
stacked and a final map of the expected tsunami wave height near the coastline was
computed, one for each case (a and b respectively), as shown below.
Tsunami wave height expected at the Greek coastline
(b)
Zoom in Crete
(a)

2. PHASE 2 Methodology
The MOST/ComMIT NOAA code and GUI interface
is used to simulate tsunami propagation and
estimate inundation zones, for the four largest
cities in the South Aegean region (Chania,
Rethimnon, Heraklion, Kalamata).
The largest known, reported and studied
earthquake event in the Eastern Mediterranean
was selected (365AD west of Crete with
considered magnitude Mw=8.5), as a key example
for our study.
High resolution DEMS were joined with 5m
resolution in topography and 30m in bathymetry,
respectively.
The results were further processed via a GIS tool
interface and inundation maps were produced for
the four selected cities.
For the Heraklion city inundation maps focused on
areas with public and tourist interest were
produced. They were used in a workshop-exercise
with local civil protection agencies, under the
leading coordination of the Department of Civil
Protection of the Decentralized Administration of
Crete.
For further information and queries please contact: nmelis@noa.gr
This work has been completed
under the project KRIPIS – ASPIDA
In Phase 2 of our study, we considered the 365AD earthquake event that devastated the East Mediterranean Basin (Shaw et al., 2008) as the example to apply the
methodology (seismic/tsunami source, tsunami propagation, coastal impact). This most extensively studied event regarding modelling, synthetics and field data justification
investigations was selected. We prepared using MOST (Initial Conditions (left) and Maximum Wave Height Propagation for the selected source (right)). The latter is the input
for the MOST/ComMIT platform with the GUI interface as a user friendly tool.
REFERENCES
Annunziato, A. (2007). The Tsunami Assessment Modelling System by the Joint Research Centre. Science of Tsunami Hazards, 26:2, 70–92.
Gica, E., Spillane, M., Titov, V.V., Chamberlin, C.D., and Newman, J.C. (2008), Development of the forecast propagation database for NOAA’s Short-term Inundation Forecast for
Tsunamis (SIFT), NOAA Tech. Memo. OAR PMEL-139, NTIS: PB2008-109391, 89 pp.
Mitsoudis, D. A., E. T. Flouri, N. Chrysoulakis, Y. Kamarianakis, E. A. Okal, C. E. Synolakis, (2012). Tsunami hazard in the southeast Aegean Sea, Coastal Engineering, 60, 136–148.
Necmioglu, O. and Ozel, N. M. (2015). Earthquake Scenario-Based Tsunami Wave Heights in the Eastern Mediterranean and Connected Seas, Pure Appl. Geophys., DOI
10.1007/s00024-015-1069-y.
Okada, Y. (1985) Surface deformation due to shear and tensile faults in a half-space, Bull. Seism. Soc. Am., 75, 1435-1154.
Papaioannou, Ch. A. and B. C. Papazachos, (2000). Time-Independent and Time-Dependent Seismic Hazard in Greece Based on Seismogenic Sources, Bulletin of the
Seismological Society of America, 90, 1, 22–33.
Shaw, B., Ambraseys, N. N., England, P. C., Floyd, M. A., Gorman, G. J, Higham, T. F. G., Jackson, J. A., Nocquet, J.-M., Pain, C. C., and Piggot, M. D. (2008). Eastern Mediterranean
tectonics and tsunami hazard inferred from the AD 365 earthquake; Nature Geoscience Vol. 1 April 2008.
Synolakis, C.E., E.N. Bernard, V.V. Titov, U. Kânoğlu, and F.I. González (2007): Standards, criteria, and procedures for NOAA evaluation of tsunami numerical models. NOAA Tech.
Memo. OAR PMEL-135, NOAA/Pacific Marine Environmental Laboratory, SeaUle, WA, 55 pp.
Titov, V.V. and Gonzalez, F.I. (1997). Implementation and testing of the method of splitting tsunami (MOST), NOAA Technical Memorandum ERL-PMEL-112, PB98-122773, Pacific
Marine Environmental Laboratory, Seattle, Washington, 11 pp.
Titov, V.V. and Synolakis, C.E. (1998). Numerical modeling of tidal wave runup, J. Waterw. Port Ocean Coast. Eng. 124(4), 157–171.
Titov, V., Moore, C., Greenslade, D., Pattiaratchi, C., Badal, R., Synolakis, C., and Kanoglu, U. (2011). A New Tool for Inundation Modeling: Community Modeling Interface for
Tsunamis (ComMIT), Pure Appl. Geophys., doi:10.1007/s00024-011-0292-4.
Vamvakaris, D.A., C. B., Papazachos, C., Papaioannou, E. M. Scordilis, and G. F. Karakaisis, (2016). A detailed seismic zonation model for shallow earthquakes in the broader
Aegean area, Nat. Hazards Earth Syst. Sci., 16, 55-84, www.nat-hazards-earth-syst-sci.net/16/55/2016/, doi:10.5194/nhess-16-55-2016.
Defined Inundation Zones
at Heraklion:
west end of the city (right),
hotel / beach coastal zone
west of the city (below)
Rethimnon Kalamata
Zoom at the city of Kalamata
Heraklion
Chania
location map of selected sites and the 365AD epicenter
[ the case as it has been processed with ComMIT GUI interface in Windows (some representative screen dumps) ]
[ for these cases, the results with ComMIT (inundation zones)
are presented after some basic GIS reprocessing ]