PTWC, JMA, US NTWC Contacts

The Pacific Tsunami Warning Center (PTWC) in Honolulu, 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
1845 Wasp Boulevard, Building 176
Honolulu, Hawaii 96818
U.S.A.
Tel: +1 808 725 6300
Fax: +1 808 725 6336
Email: charles.mccreery@noaa.gov, ptwc@ptwc.noaa.gov
URL: https://tsunami.gov/

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:

Dr. James Gridley, Director
National Tsunami Warning Center
910 Felton St.
Palmer, AK  99645
U.S.A.
Phone: +1-907-745-4212
Fax: +1-907-745-6071
Email wcatwc@noaa.gov
URL: https://ntwc.ncep.noaa.gov/

Japan Meteorological Agency

• 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. Satoshi Harada
Senior Coordinator for International Earthquake and Tsunami Information
Earthquake and Tsunami Observation Division
Japan Meteorological Agency (JMA)
1-3-4 Otemachi, Chiyoda-ku, Tokyo 100-8122
JAPAN
Phone: +81-3-3284-1743
Fax: +81-3-3215-2963
Email: sharada@met.kishou.go.jp
URL: http://www.jma.go.jp/jma/indexe.html