PTWC Issues Warning for M7.7 Haida Gwaii, British Columbia Earthquake

2013-01-24T22:00:00+00:00

The 28 October 2012 (0304 UTC) / 27 October 2012 (2004 PDT, 1704 HST) magnitude 7.7 Haida Gwaii earthquake generated small, non-destructive tsunami that were measured in Alaska, British Columbia and southward to Calfornia and in Hawaii; much smaller waves were also measured throughout the Pacific. Tsunami Warnings were issued by WC/ATWC for SE Alaska and Northern British Columbia at 2007 PDT, and downgraded to Advisories at 0049 PDT 28 October for SE Alaska and at 0247 PDT for Northern BC. Advisories were also issued for Southern BC through Northern California.

A Tsunami Warning was issued by PTWC for Hawaii at 1909 HST 27 October, and downgraded to an Advisory at 0101 HST 28 October. Waves up to 5 ft were observed on Maui and the Hawaii Island, but little damage was reported statewide. One person died on Oahu during the tsunami warning when a speeding vehicle rammed into parked cars that were waiting for the closed coastal road to reopen.

Captions:
Left: PTWC RIFT model simulation showing the predicted maximum off-shore tsunami wave amplitudes from the 0304 UTC 28 October 2012 earthquake. Courtesy PTWC.

Right top: A 80 cm amplitude tsunami was recorded at Kahului, Maui. Courtesy of WC/ATWC.

Right bottom: A 58 cm amplitude tsunami was recorded at Kawaihae, Hawaii. Courtesy of WC/ATWC.


Left: Canada sea level records. Courtesy of Sasha Rabinovich, Denny Sinnott, Canadian Hydrographic Service. Right: Canada sea level stations. Courtesy of Sasha Rabinovich, Denny Sinnott, Canadian Hydrographic Service.

For more technical information, visit this tsunami's event page (click here).

28 October 2012 (UTC), Mw 7.7, Queen Charlotte Islands, Haida Gwaii, Canada Tsunami

2012-10-28T22:00:00+00:00

The 28 October 2012 (0304 UTC) / 27 October 2012 (2004 PDT, 1704 HST) magnitude 7.7 Haida Gwaii earthquake generated small, non-destructive tsunami that were measured from Alaska to Calfornia and in Hawaii; much smaller waves were also measured throughout the Pacific. Tsunami Warnings were issued by WC/ATWC for SE Alaska and Northern British Columbia at 2007 PDT, and downgraded to Advisories at 0049 PDT 28 October for SE Alaska and at 0247 PDT for Northern BC. Advisories were also issued for Southern BC through Northern California. A Tsunami Warning was issued by PTWC for Hawaii at 1909 HST 27 October, and downgraded to an Advisory at 0101 HST 28 October. Waves up to 5 ft were observed on Maui and the Hawaii Island, but little damage was reported statewide. One person died on Oahu during the tsunami warning when a speeding vehicle rammed into parked cars that were waiting for the closed coastal road to reopen.

According to the NOAA National Geophysical Data Center / World Data Service for Geophysics / (http://www.ngdc.noaa.gov/hazard/hazard/) Global Historical Event database, 7 confirmed local tsunamis have occurred in the British Columbia region over history. The largest runup was 9.0 m from a M7.3 June 23, 1946 earthquake that generated numerous landslides and ensuing tsunami. A major submarine slope failure on April 27, 1975 generated tsunami waves of up to 4.1 m in Kitimat Inlet, British Columbia. Tsunami waves up to 5.0 m that were probably generated from the March 28, 1963 underwater slump were observed on Graham and Queen Charlotte Islands. Minor traces on tide gauges have been observed in British Columbia from 41 teletsunamis generated by large earthquakes around the Pacific Rim as well as the M9.1 2004 Indian Ocean tsunami. The largest runups were 6.4 m at Port Alberni and 5 m at Shields Bay from the M9.2 March 28, 1964 Prince William Sound, Alaska, USA earthquake and tsunami. The 1964 tsunami caused $10 million damage on Vancouver Island.

1) Alert Information	PTWC Official Messages Pacific (DOC, 69 KB) Hawaii (DOC, 30 KB) WC/ATWC Official Messages (DOC, 140 KB) Tsunami Travel Time Map (WC/ATWC, JPG, 189 KB) Offshore Maximum Amplitude (forecast) - RIFT model (PTWC, JPG, 98 KB) Offshore Maximum Aplitude (forecast) - WC/ATWC model (WC/ATWC, JPG 222 KB)
2) Sea Level	British Columbia, Canada, Sea level records (detided) (Canadian Hydrographic Service, JPG, 971 KB) British Columbia, Canada, Sea level records (Canadian Hydrographic Service, JPG, 190 KB) Sea Level Observations (PTWC, 30 Oct, rev 3 Nov, DOC, 42 KB) Sea Level Observations (WC/ATWC, Website) Sitka Sea Level Gauge (PTWC, PDF, 132 KB) DARTs/tsunameters (NDBC, PDF, 238 KB) British Columbia, Canada, Sea Level Station Map (Canadian Hydrographic Service, PNG, 52 KB) Pacific Ocean, Sea Level Station Map (PTWC/ITIC, PDF, 969 KB)
3) Seismic	Event Page (USGS, Website) Earthquake Aftershocks through 29 Oct 2046 UTC (USGS, JPG, 812 KB) Historical Seismicity, M6+ (PTWC, JPG, 155 KB) Historical Seismicity, M3+, 1900-present (USGS, JPG, 528 KB) Earthquake Summary Poster (USGS, PDF, 53.8 MB)
4) Model Simulations	Offshore Maximum Amplitude (post-event, SIFT model) (NOAA PMEL, JPG, 1.3 MB) Tsunami Propagation movie (SIFT model) (NOAA PMEL, YouTube) NOAA PMEL Event Site (Website)
5) Data and Information Sites
6) Media	Haida Gwaii, Queen Charlotte Island, Canada: B.C. communities say they don't wait for a tsunami warning before taking action (Vancouver Sun, 29 Oct 2012, PDF, 84 KB) Hawaii: Lessons learned from tsunami warning (Hawaii TV, KHON, 28 Oct 2012, PDF, 152 KB) PTWC: Sparse data make it 'tricky'. Deep-water sensors did not help scientists make good forecasts (Honolulu Star-Advertiser, 29 Oct 2012, PDF, 1.5 MB) Canada: BC tsunami preparations on the agenda following earthquake (Huffington Post Canada, 30 Oct 2012, Website) Hawaii: Tsunami Brings Evacuation, Debris (The Molokai Dispatch, 28 Oct 2012, Website) Hawaii: Reports of Tsunami Damage Scarce in Maui County (Maui Now, 29 Oct 2012, Website)
7) Photos, Satellite Imagery
8) Videos
9) Post-Earthquake Post-Tsunami Surveys
10) Other

2012 Tsunamis - International Tsunami Information Center

PTWC Issues Warning for M7.7 Haida Gwaii, British Columbia Earthquake

28 October 2012 (UTC), Mw 7.7, Queen Charlotte Islands, Haida Gwaii, Canada Tsunami