Plot of Sumatra tsunami records at 6 stations in British Columbia
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Alexander B. Rabinovich, D.Sc.
Institute of Ocean Sciences, Canada
http://www-sci.pac.dfo-mpo.gc.ca/osap/projects/tsunami/tsunamiasia_e.htm
Two other stations: Prince Rupert and Queen Charlotte City are empty:
- Prince Rupert has a bad admittance characteristic suppressing all high frequency oscillations
with periods less than 2 hours (see Figure 7 in Rabinovich and Thomson, 2004).
- QCC is sheltered from the open ocean.
We are still waiting for information form Langara, located near to the northern end of the Queen Charlotte Islands.
Information from this station is normally, very noisy.
Estimated parameters of the recorded waves:
Wave height, duration, periods:
Winter Harbour 21 cm, 3.8 days, 42 min (also 57 and 31 min)
Tofino 15.4 cm, 3.0 days, 53 min
Victoria 11.7 cm, 2.4 days, 53 min
Bella Bella 9.0, 3.0 days, 53 min
Port Hardy 4.5 cm, unsteady, ~ 1.5 days, mixture: 12.5, 25 and 70 min
Bamfield 4.5 cm, unsteady, ~ 1.0 day, 20 min
Tsunami arrival times (TAT) are not clear
The very approximate estimates are:
(1) The actual arrival time was much later (10-12 hours) than it was predicted. (see PTWC and WC/ATWC estimates)Winter Harbour. 1st train: 27-12 08:45 GMT; 2nd (main) train: 12:15 GMT
Tofino: 1st train: 27-12 9 :00 GMT, 2nd (main) train 11:55 GMT
Victoria: 27-12 14:20 GMT
Bella Bella: 27-12 10:20 GMT (?? 1st train?)
Bamfield: 27-12 14:40 (??) GMT
Port Hardy: 27-12 13:45 GMT
(2) Apparently different trains of tsunami waves were arriving to the observational sites
by different ways, probably after multiple reflection.
Quite long ringing of tsunami oscillations in Winter Harbour, Tofino, Bella Bella, and Victoria
also indicates that there were several sources of incoming waves.
Alexander B. Rabinovich, D.Sc.
Institute of Ocean Sciences
9860 West Saanich Rd.
Sidney, BC, V8L 4B2 Canada
Fax: (+1-250)-363-6746
Tel: (+1-250)-363-6668
E-mail: RabinovichA@pac.dfo-mpo.gc.ca