[Faline]

Scientists have captured the atmospheric signature of a tsunami in a discovery that could lead to an early warning system for the phenomenon.
A study by the University of Illinois captured the airglow signature of the tsunami that struck the Japanese coast on March 11 using an observatory on the island of Hawaii.
It was found at a height of 250km above the earth's surface and preceded the giant wave striking the coast by around an hour.

Scientists have mapped the airflow in the atmosphere during the Japanese earthquake which could lead to developments of an early warning system. The red light represents the tsunami at ground level:


Airglow is the greenish layer of light that is found when molecules combine after being split by sunlight.
The discovery, which was reported in the journal Geophysical Research Letters, also confirms a theory that was developed in the 1970s.
Those studies suggested that tsunamis could be observed in the upper atmosphere, but until now this had only been demonstrated by using radio signals.

The study focused on the fact that tsunamis generate atmospheric gravity waves as they travel across the ocean.
These waves have the potential to stretch several kilometres into the sky causing changes that can be imaged due to decreases in air density.
The University of Illinois team were led by Jonathan Makela, a professor of electrical and computer engineering.

The discovery by scientists could lead to a warning system for tsunamis - and giving people enough time to evacuate before the deadly waves strike:


After making the images, Makela, alongside graduate student Thomas Gehrels, joined forces with teams in France, Brazil and at a New York University to perform a detailed analysis.
They found the wave properties matched those from a ocean-level tsunami, confirming the signature originated from the Japanese tsunami.
Professor Makela now believes that camera systems could be developed to create an early warning system.
Currently, scientists use ocean-based buoys and models to track and predict tsunamis.
But a camera system could actually image the whole sky, watching for the changes in the atmosphere.
And to get round problems a ground based system would create, the scientists suggest a system be mounted to a satellite.
Makela added that a reliable system could be some way off as scientists need to develop algorithms to analyse and filter any data in real time.
But Professor Makela added: 'This is a reminder of how interconnected our environment is.
'This technique provides a powerful new tool to study the coupling of the ocean and atmosphere and how tsunamis propagate across the open ocean.'

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http://www.dailymail.co.uk/sciencete...ng-system.html

[candymosh]

[Viking64]

Interesting!!

[NaTaS]

yup, looks like a wave.

[Jere]