Tsunami warning - if you're in contact with cruisers in the Pacific, let them know

[wooden 'ed]

http://www.nytimes.com/2010/02/28/world/americas/28chile.html?hp

[Ian McColgin]

Saw on last night's news the Hawaii evacuation and the good fortune that it was not a big wave there.

From what I could see of the news, the tsunami alert has been comprehensive.

It's interesting how hard it is to corrolate a seismic event with the actual power of a tsunami.

[Peerie Maa]

It's interesting how hard it is to corrolate a seismic event with the actual power of a tsunami.

It could be that tsunami are caused by large displacements of rock, in effect an instantaneous change in volume of the container. Whereas an earth quake is a high energy vibration of the rock, with relatively little permanent displacement.
The analysis of the seabed published after the Indonesian tsunami illustrates this quite clearly. A sub-sea earthquake that does not displace the sea bed or shears it in a horizontal direction rather than vertically may not generate any tsunami.

[rbgarr]

I wonder whether sailors far at sea, were they in a flat, windless calm, would see the ripple of the tsunami wave pass by at hundreds of miles an hour.

[paladin]

I have been relaying messages most of the night. Maritime Mobile net out of J'Burg and Hong Kong have been transmitting warnings every few hours. At 1800 zulu the official net time today all world cruisers normally check in to the net or monitor it and will get the message if their radios are on. The net is on SSB at 14.313 MHz.

[Peerie Maa]

I wonder whether sailors far at sea, were they in a flat, windless calm, would see the ripple of the tsunami wave pass by at hundreds of miles an hour.

One cargo vessel reported the Kracatoa tsunami. They experienced rising as the very shallow wave crest passed under them and then decending down the back of the crest. The crest was so long that its slope was not noticeable.
Wiki puts it well:
While everyday wind waves have a wavelength (from crest to crest) of about 100 metres (330 ft) and a height of roughly 2 metres (6.6 ft), a tsunami in the deep ocean has a wavelength of about 200 kilometres (120 mi). Such a wave travels at well over 800 kilometres per hour (500 mph), but due to the enormous wavelength the wave oscillation at any given point takes 20 or 30 minutes to complete a cycle and has an amplitude of only about 1 metre (3.3 ft).[10] This makes tsunamis difficult to detect over deep water. Ships rarely notice their passage.