The Pacific Tsunami Warning Center (PTWC) in Ewa Beach, Hawaii, USA serves as the operational headquarters of the Pacific tsunami warning system; sub-regional centres in Japan and Alaska, USA work with PTWC to provide international tsunami alerts for events occurring in the Pacific Ocean and within the marginal seas of the north- and southwest Pacific. The messages are advisories to designated national authorities, as each country is individually responsible for issuing warnings and public safety information to its population. The PTWC disseminates tsunami alerts to over 100 points across the Pacific.

To do this, the PTWC works closely with other regional and national centers in monitoring seismological and sea level stations and instruments around the Pacific Ocean to evaluate potentially tsunamigenic earthquakes, and issue alerts within 10 minutes after the event. The PTWS makes use of about 600 seismic stations around the world to locate potentially tsunamigenic earthquakes, and accesses about 500 sea level stations globally to verify the generation and evaluate the severity of a tsunami.


Extracted from PTWS Operational User's Guide 2010, US NTWC name change 2014


Pacific Tsunami Warning Center

The PTWC started in 1949 following an unwarned tsunami from Alaska in 1946 that killed 159 people in Hawaii.  It is administratively part of the NOAA NWS Pacific Region.  Its mission responsibilities include serving as the:

  • International Tsunami Warning Center for the PTWS, and headquarters and coordinator of warning center activities in the Pacific;
  • Tsunami Warning Center for all US national interests in the Pacific outside of Alaska and the US West Coast;
  • Hawaii, American Samoa, Guam, and CNMI Tsunami Warning Center;
  • Interim Tsunami Warning Center for the South China Sea (along with NWPTAC)
  • Interim Tsunami Watch Provider for the Caribbean and adjacent regions.

Service as the Interim Tsunami Watch Provider for the Indian Ocean (along with JMA) was discontinued in 2012.


The contact information for PTWC is:

Dr. Charles McCreery, Director

Pacific Tsunami Warning Center

91-270 Fort Weaver Road

Ewa Beach, Hawaii 96706


Phone:  1-808-689-8207

Fax:  1-808-689-4543




US National Tsunami Warning Center

The US NTWC (formerly WC/ATWC) started in 1967 after the 1964 Alaska earthquake and tsunami as the tsunami warning center for Alaska.  Its area of responsibility expanded to include the west coast of North America in 1982, and to all coasts of North America in 2005.  It is administratively part of the NOAA NWS Alaska Region.  Its mission responsibilities include serving as the:

  • US Tsunami Warning Center for all US states except Hawaii
  • US and International Tsunami Warning Center for Puerto Rico and the Virgin Islands
  • International Tsunami Warning Center for Canada


The contact information for NTWC is:

Mr. Paul Whitmore, Director

National Tsunami Warning Center

910 Felton St.

Palmer, AK  99645


Phone:  +1-907-745-4212

Fax: +1-907-745-6071




Japan Meteorological Agency

The Ministry of Land, Infrastructure, Transport, and Toursim of Japan oversees the Japan Meteorological Agency that operates and administers the tsunami warning programme for Japan.

The Director of the Earthquake and Tsunami Observations Division within the Seismological and Volcanological Department of JMA administers the Tsunami Warning Center in Japan.  The JMA National Center in Tokyo has mission responsibility as:

  • National tsunami warning center (started in 1952)
  • International Advisory service for the Northwest Pacific (through JMA/NWPTAC, since 2005)
  • Interim Tsunami Advisory Center for the South China Sea as part of the expanded coverage of the NWPTAC (with USA PTWC, since 2006)

Service as the Interim Tsunami Watch Provider for the Indian Ocean (with USA PTWC, since 2005) was discontinued in 2012.


The contact information for the JMA Tsunami Warning Center is:

Mr. Takeshi Koizumi

Senior Coordinator for International Earthquake and Tsunami Information

Seismological and Volcanological Department

Japan Meteorological Agency (JMA)

1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122


Phone: +81-3-3284-1743

Fax: +81-3-3215-2963





find us on facebook

Featured Resources

banner materiales educativos

Regional Disaster Information Center (Latin America & the Caribbean)

A database of Spanish language materials focused on tsunami preparedness.
dsc00149 thumbnail

Post-Tsunami Survey:
El Salvador Summary Video

Learn the basics of a post-tsunami survey.

TsunamiTeacher USA
Tsunami Basics

Also on YouTube youtube_logo
(w/closed captioning)

Learn the basics of tsunamis. Available in English and Samoan.

Tsunamis on the Move

Tsunami Awareness Poster

Awareness poster available in English, Chinese, French, Japanese, Korean, Portuguese, Singalese.


Global Hazard Maps

Posters of Tsunami Sources, Significant Earthquakes and Significant Volcanic Eruptions. Also Tsunami Sources Icosohedron Globe.

great waves en 12 small thumbnail

Tsunami, The Great Waves

Available in English, Spanish, French and Chinese.


tsunami glossary 2013 thumbnail

Tsunami Glossary

Available in English, Arabic, Spanish, French and Bahasa. 



Where the First Wave Arrives in Minutes

Available in English, Bahasa, Spanish and French.


DVD copies for PC and Macintosh computers are available free of charge from the ITIC, Hawaii (

Hosted by:
UNESCO/IOC Project Office for IODE Oostende, Belgium
© 2015 International Tsunami Information Center | A UNESCO/IOC-NOAA Partnership
1845 Wasp Boulevard, Building 176, Honolulu, HI 96818, USA | Tel: +1 808 725 6050 | Fax: +1 808 725 6055