Tsunami was tracked by radar for first time


Scientists in California got an early look at the tsunami generated by the massive earthquake in Japan as it rippled across the Pacific Ocean.

The March 11 Japan tsunami was picked up by high-frequency radar in California and Japan as it swept toward their coasts, according to U.S. and Japanese scientists. This is the first time a tsunami has been observed by radar, raising the possibility of new early warning systems.

"It could be really useful in areas such as southeast Asia where there are huge areas of shallow continental shelf," said John Largier, an oceanographer and study team member from the University of California, Davis. The continental shelf is the perimeter of a continent that is underwater and gradually descends to the ocean floor.

Largier and his colleagues have been using a high-frequency radar array at their lab to study ocean currents for the last 10 years. Together with collaborators from Hokkaido and Kyoto universities in Japan and San Francisco State University, the researchers used data from radar sites at Bodega Bay and Trinidad, Calif, and two sites in Hokkaido, to look for the tsunami offshore.

The radar detection is the latest in the string of new ways the Japan earthquake and tsunami were observed.Satellite images found that the tsunami was so powerful that it broke off huge icebergs thousands of miles away in the Antarctic. Scientists also found that the earthquake rattled the planet's upper atmosphere.

In the new study, scientists noticed that the radar picks up not the actual tsunami wave — which is small in height while out at sea — but changes in currents as the wave passes.

The researchers found they could see the Japan tsunami once it entered shallower coastal waters over the continental shelf. As the waves enter the shallower water, they slow down, increase in height and decrease in wavelength until finally hitting the coast.

The continental shelf off California is quite narrow, and approaches to the coast are already well-monitored by pressure gauges, Largier said. But he said radar detection could be useful, for example, on the East Coast or in Southeast Asia, where there are wide expanses of shallow seas.

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-1 ( +0 / -1 )

Pity such technology is only developed for the military. If it was originally designed for civilian use, maybe many lives could have been saved?

0 ( +1 / -1 )

That is not military technology, not like the internet which was military technology yet look where it is now.

2 ( +2 / -0 )

That looks so scarey..

0 ( +0 / -0 )

Pity such technology is only developed for the military. If it was originally designed for civilian use, maybe many lives could have been saved?

Where in the article do you read anything about miltary, funding or otherwise? The researchers are associated with Hokkaido and Kyoto universities in Japan and San Francisco State University in the US. The stated purpose has been to study ocean currents and they have been doing so with the radar stations for the last 10 years. This was the first time they have observed tsunami in radar data.

The above information was all within JT's article, but seemingly glossed over. In another news article, I found the facility in the US is funded by the California state government, not the US Federal government. Because of this fact, it unlikely to be a miltary project and cannot be a miltary only project.

Tying this ongoing research with miltary funding as a possible reason for lives lost is uninformed, disingenous, and just plain wrong. Perhaps posters on JT should take a step back, a deep breath, and a minute to think before they post a "an off-the-cuff statement. But it seems that would take more time and effort than most posters seem to be willing to spend. Especially if they might discover they are wrong. Posting unsubstantiated claims as "fact" isn't very helpful, but seems to be common on JT.

A more useful action might be to push for more funding into research that can help, while accepting that such research takes time.

0 ( +0 / -0 )

Click on the photo to enlarge it - does it not look like the tsunami is giving the Pacific the finger?

0 ( +0 / -0 )

Nice defense of the large slice of each countries GDP that goes to Military affairs, but you are wrong. The development of radar and sonar is mostly due to military uses. Of course this is a civilian use, as it was used by researchers and used in this simulation. However, if a far greater proportion of government budgets was spent on innovations for civilian use( like the story), or for business(GW and food security) many, many lives would be saved, without mentioning the fact military purposes are based around deadly defense and attack.

0 ( +0 / -0 )

Let's hope we can save lives in the future with this.

0 ( +0 / -0 )

Let's just hope that the alignment of comet Elenin which is supposed to trigger these events is nothing but a hoax otherwise we will have an even bigger earthquake/tsunami on September 26th.

0 ( +0 / -0 )

Fascinating. here is a 3,000 x 2,000 pixels @ 24 bits per pixel 2.4 MB version of the same photo . if you want to print it off or really look closely

Looks like a retinal scan!

0 ( +0 / -0 )

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