Thursday, October 1, 2009

Tsunami info


On Tuesday evening we had a small tsunami, or tidal wave, the result of an 8.0 earthquake in Samoa in the south Pacific.

Although the effect seemed unnoticeable here, someone in the harbor may have detected a change in water elevation of about a foot, with a period of around 15 minutes. A time-lapse camera may have been able to record the event.

Tide gauges around the pacific detected these 'tidal waves' as in this example from Hawaii. Because 'tidal waves' have such a long wavelength, they travel at high speed across the ocean - only 11 hours from Samoa to North America!

From Wikipedia: A tsunami (津波) (pronounced /(t)suːˈnɑːmi/) is a series of water waves (called a tsunami wave train[1]) that is caused by the displacement of a large volume of a body of water, such as an ocean. The original Japanese term literally translates as "harbor wave."