The Institute of Geodynamics and its tsunami unit (HL-NTWC) perform research in the areas of earthquake and engineering seismology, historical seismicity and paleoseismology, active tectonics including GPS research, geophysics, volcanology and tsunami science. more


Since 28 August 2012, the HL-NTWC operates a 24/7 tsunami monitoring and alerting service for Greece and the eastern Mediterranean Sea, providing warning messages to the General Secretariat for Civil Protection in Greece (GSCP). more

news & events

History of the HL-NTWC

Establishment of the Greek Seismological Service (today National Observatory of Athens-Institute of Geodynamics, NOA-IG).
Installation at NOA-IG of the first reliable seismic instrument of Mainka type.
The national seismograph Centre of NOA-IG becomes member of the WWSSN (World-Wide Standard Seismographic Network).
NOA-IG was partner at the first pan-European GITEC tsunami research project.
NOA-IG was partner at the pan-European GITEC-TWO tsunami research project.
In the frame of GITEC-TWO a very first effort was made for the design and development of an experimental, telemetric tsunami warning system focusing in the western segment of the Hellenic Arc. The local system comprised a number of new seismic stations, two tide-gauges of pressure type, and an acquisition unit installed at the premises of NOA in Athens for collecting and archiving data (Papadopoulos, 2003a.). Although this vision survived only for a while beyond the life of GITEC-TWO, it was revitalized after the devastating Indian Ocean tsunami of 2004 with the development of a national tsunami warning system.
June: The IOC/UNESCO country-member delegations (Paris, June 2005) decided to establish the North-Eastern Atlantic, Mediterranean and connected seas Tsunami Warning System (NEAMTWS).
Nov.: Establishment of the Intergovernmental Coordination Group (ICG) of NEAMTWS with NOA-IG representing Greece which was one of the founding country-members.
The HL-NTWC started to build-up.
Sept.: The HL-NTWC was officially established by national law.
28th August: The HL-NTWC was declared as operational for a 24/7 tsunami monitoring and alerting service for Greece and the eastern Mediterranean Sea, providing confidential warning messages to the General Secretariat for Civil Protection in Greece (GSCP) which has the responsibility for the downstream component of the system and the dissemination of warning messages. Since then the HL-NTWC acted also as Candidate Tsunami Service Provider in the framework of the NEAMTWS/IOC/UNESCO providing the tsunami messages also to several subscribers by following the requirements, functions and other standards established and adopted by the ICG/NEAMTWS/IOC/ UNESCO. The recipients of tsunami messages from HL-NTWC include relevant authorities in several countries in Europe and in the Mediterranean, the Emergency Response Coordination Centre (ERCC) of EU in Brussels, the IOC/UNESCO (Paris), the Joint Research Centre (JRC) of EC in Ispra and other tsunami warning centres of NEAMTWS.
Apr.: The national tide-gauge network started to build-up with the installation of three stations donated by JRC/EC. The number of stations increased drastically in the next years with the support by various sources.
Dec.: Establishment of a local earthquake and tsunami warning system in Rhodes Isl., SE Aegean Sea, Greece, with the support of the NEARTOWARN preparedness project supported by DG-ECHO/EC.
26-28 Sept.: After the ICG/NEAMTWS/IOC/ UNESCO decided for an accreditation procedure to be initiated, during 2016 the HL-NTWC was positively evaluated by an international team of experts which recommended the accreditation of the HL-NTWC. The accreditation was approved by the assembly of the national delegations at the 13th annual meeting of ICG/NEAMTWS/IOC/ UNESCO held in Bucharest. Since then the HL-NTWC acts as Tsunami Service Provider in the frame of ICG/NEAMTWS/IOC/ UNESCO.
27th June: The accreditation procedure completed with the Accreditation Ceremony organized during the General Assembly of IOC/UNESCO in Paris, where the four centres accredited (CENALT, INGV, KOERI, NOA-IG) were represented.
July: In collaboration with JRC/EC the “Last Mile” project initiated for the establishment of a local earthquake and tsunami warning system in Kos Isl., SE Aegean Sea, Greece, with support by DG-ECHO/EC.
By now the national tide-gauge network of the HL-NTWC includes 18 stations.


The Institute of Geodynamics of NOA, including HL-NTWC, participates in several research, infrastructure and education projects as well as in pilot studies funded by national and international organizations including EU.
Projects undertaken in last years include:

NOA-IG gets also funding from the Earthquake Planning & Protection Organization (Greece) for maintenance of the national seismograph system. Through a MoU between NOA and INGV a bilateral project is ongoing for expanding the cGPS network in western Greece. This project, among other interests, is of importance for tsunami warning purposes too.

Internal Training

Internal training of the duty officers involved in the 24/7 operation of the HL-NTWC is carried on constantly, since the operators are taking shifts. Talks and presentations are organized covering a wide range of topics, such as the operating procedures of a tsunami service provider, the operation of dedicated software (TAT, Seiscomp3 etc.) or of wider scientific interest, such as earthquake and tsunami hazards and sea-level measurements.


Lofos Nymphon - Thissio
PO Box 20048
11810, Athens, Greece

Contact Us

 +30 2103490152
 +30 2103490180

About Us

The HL-NTWC is supported by the staff of NOA-IG and includes
  • researchers and other scientific staff,
  • part-time earthquake and tsunami analysts,
  • technicians.

Director of HL-NTWC is the NOA-IG director.
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