Feeds

Boffins: Japan was hit by 'double-wave' tsunami

Two became one

New hybrid storage solutions

Boffins from NASA and Ohio State University have discovered that the tsunami that hit Japan in March 2011 was a so-called ‘merging tsunami’.

Merging tsunami data from two satellites. Credit: NASA/JPL-Caltech/Ohio State University (click to enlarge)

The idea of a merging tsunami, where two or more wave fronts join to form a single wave capable of travelling long distances, has long been hypothesised, but never before confirmed.

NASA and European radar satellites captured at least two wave fronts on the day of the Japanese tsunami, which merged to form a single double-high wave far out at sea that could travel to the coast without losing power.

The two fronts were pushed together by ocean ridges and undersea mountain chains near the tsunami’s origin.

The data gathered could help scientists to improve tsunami forecasts.

"It was a one in 10 million chance that we were able to observe this double wave with satellites," principal investigator Y Tony Song said.

"Researchers have suspected for decades that such 'merging tsunamis' might have been responsible for the 1960 Chilean tsunami that killed about 200 people in Japan and Hawaii, but nobody had definitively observed a merging tsunami until now," he added.

"It was like looking for a ghost. A NASA-French Space Agency satellite altimeter happened to be in the right place at the right time to capture the double wave and verify its existence."

The trouble with tsunami forecasts now is that while the underwater earthquake that is the origin of the event can be pinpointed, the waves themselves often seem to go off in random directions, causing massive destruction in some places but leaving nearby areas unharmed.

The researchers think that ridges and underwater mountains can deflect parts of the initial tsunami wave to form a number of wave fronts.

Current hazard maps that try to predict where tsunamis will hit only take into consideration sea-floor topography near shorelines, but this research suggests scientists might be able to create maps that also take into account ridges and mountains far from shore.

"Tools based on this research could help officials forecast the potential for tsunami jets to merge," Song said. "This, in turn, could lead to more accurate coastal tsunami hazard maps to protect communities and critical infrastructure." ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Thought that last dinosaur was BIG? This one's bloody ENORMOUS
Weighed several adult elephants, contend boffins
Chelyabinsk-sized SURPRISE asteroid to skim Earth, satnav birds
Space rock appears out of nowhere, buzzes planet on Sunday
City hidden beneath England's Stonehenge had HUMAN ABATTOIR. And a pub
Boozed-up ancients drank beer before tearing corpses apart
'Duck face' selfie in SPAAAACE: Rosetta's snap with bird comet
Probe prepares to make first landing on fast-moving rock
Square Kilometre Array reveals its 1.6TB-a-day storage and network rigs
Boolardy Engineering Test Array - aka BETA - is about to come out of Beta
LOHAN invites ENTIRE REG READERSHIP to New Mexico shindig
Well, those of you who back our Kickstarter tin-rattling...
prev story

Whitepapers

Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.
Top 5 reasons to deploy VMware with Tegile
Data demand and the rise of virtualization is challenging IT teams to deliver storage performance, scalability and capacity that can keep up, while maximizing efficiency.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.