Posted on 12/22/2021 8:14:37 PM PST by BenLurkin
A new study finds the magnetic field generated by a tsunami can be detected a few minutes earlier than changes in sea level and could improve warnings of these giant waves.
Tsunamis generate magnetic fields as they move conductive seawater through the Earth's magnetic field. Researchers previously predicted that the tsunami's magnetic field would arrive before a change in sea level, but they lacked simultaneous measurements of magnetics and sea level that are necessary to demonstrate the phenomenon.
The new study provides real-world evidence for using tsunamis' magnetic fields to predict the height of tsunami waves using data from two real events—a 2009 tsunami in Samoa and a 2010 tsunami in Chile—that have both sets of necessary data. The new study was published in AGU's Journal of Geophysical Research: Solid Earth, which focuses on the physics and chemistry of the solid Earth.
The study confirms the magnetic field generated by a tsunami arrives ahead of sea-level change and that its magnitude can be used to estimate the tsunami's wave height. How much earlier the magnetic field arrives depends on water depth, but in their results, the study authors found the early arrival time to be about one minute prior to sea level change over a 4,800-meter deep sea.
(Excerpt) Read more at phys.org ...
Good. That gives me time to put away the test equipment.
One minute before sea level change. Is this the sea level change where the water draws back from the shoreline, or the big crashing wave?
I think they mean right at the location of the quake.
I guess I better install magnetic tsunami detectors in my Tennessee Possum Holler International Seaport.
I’ll need those after the artic ice shelf collapses and my seaport becomes operational.
After re-reading the article, it occurs only in deep water, rather than near the shoreline. It could provide time to anticipate disaster.
Interesting... But you’d think the earthquake detection would itself provide even MORE warning time.
Question — is there a big crashing wave, or is it more of a powerful surge without much height? I suspect it may be based on the local ocean floor, but if I recall correctly, the Japan tsunami that wiped out the nuclear reactor was more of an inundation than crashing wave. I defer to your expertise on the answer....
Oh my
Thank you for the education
Wow! Hey, thanks for turning me on to the Petersens! I’ve been listening to them since I came across your link. Wow!
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