From the University of Illinois, something quite interesting, long speculated on, now confirmed.
Tsunami airglow signature could lead to early detection system
Researchers at the University of Illinois have become the first to record an airglow signature in the upper atmosphere produced by a tsunami using a camera system based in Maui, Hawaii.
The signature, caused by the March 11 earthquake that devastated Japan, was observed in an airglow layer 250 kilometers above the earth’s surface. It preceded the tsunami by one hour, suggesting that the technology could be used as an early-warning system in the future. The findings were recently published in the peer-reviewed Geophysical Research Letters.
The observation confirms a theory developed in the 1970s that the signature of tsunamis could be observed in the upper atmosphere, specifically the ionosphere. But until now, it had only been demonstrated using radio signals broadcast by satellites.
“Imaging the response using the airglow is much more difficult because the window of opportunity for making the observations is so narrow, and had never been achieved before,” said Jonathan Makela, an associate professor of electrical and computer engineering and researcher in the Coordinated Science Laboratory. “Our camera happened to be in the right place at the right time.”
Tsunamis can generate appreciable wave amplitudes in the upper atmosphere – in this case, the airglow layer. As a tsunami moves across the ocean, it produces atmospheric gravity waves forced by centimeter-level surface undulations. The amplitude of the waves can reach several kilometers where the neutral atmosphere coexists with the plasma in the ionosphere, causing perturbations that can be imaged.
On the night of the tsunami, conditions above Hawaii for viewing the airglow signature were optimal. It was approaching dawn (nearly 2:00 a.m. local time) with no sun, moon or clouds obstructing the view of the night sky.
Along with graduate student Thomas Gehrels, Makela analyzed the images and was able to isolate specific wave periods and orientations. In collaboration with researchers at the Institut de Physique du Globe de Paris, CEA-DAM-DIF in France, Instituto Nacional de Pesquisais Espaciais (INPE) in Brazil, Cornell University in Ithaca, NY, and NOVELTIS in France, the researchers found that the wave properties matched those in the ocean-level tsunami measurements, confirming that the pattern originated from the tsunami. The team also cross-checked their data against theoretical models and measurements made using GPS receivers.
Makela believes that camera systems could be a significant aid in creating an early warning system for tsunamis. Currently, scientists rely on ocean-based buoys and models to track and predict the path of a tsunami. Previous upper atmospheric measurements of the tsunami signature relied on GPS measurements, which are limited by the number of data points that can be obtained, making it difficult to create an image. It would take more than 1,000 GPS receivers to capture comparable data to that of one camera system. In addition, some areas, such as Hawaii, don’t have enough landmass to accumulate the number of GPS units it would take to image horizon to horizon.
In contrast, one camera can image the entire sky. However, the sun, moon and clouds can limit the utility of camera measurements from the ground. By flying a camera system on a geo-stationary satellite in space, scientists would be able to avoid these limitations while simultaneously imaging a much larger region of the earth.
To create a reliable system, Makela says that scientists would have to develop algorithms that could analyze and filter data in real-time. And the best solution would also include a network of ground-based cameras and GPS receivers working with the satellite-based system to combine the individual strengths of each measurement technique.
“This is a reminder of how interconnected our environment it,” Makela said. “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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Maybe they can link the full moon with king tides too?
Measurements by GPS receivers? Placed ones? Moving ones? Are they joking? Measuring time differences against what? Location differences against what? Just like to know.
If the Tsunami is the cause of the ripple in the ionosphere, how can it be used to predict the tsunami? Maybe I missed something.
tallbloke – the paper says “It preceded the tsunami by one hour“. Presumably it means it preceded the tsunami reaching the coast by one hour. That would still be very useful, because (I’m guessing) tsunamis can’t always be detected at source.
It began one hour before the quake/tsunami.
There’s clearly “more to know” about the sequencing and mechanisms!
I wonder if it is a tsunami effect, or the ionospheric airglow is caused by strong geomagnetic oscillations that are often (but not always) associated with the large earthquakes.
“It preceded the tsunami by one hour”. In Hawaii, not Japan. People on the Tohoku coast started evacuating directly after the earthquake. No warning was needed. Those who couldn’t evacuate in time, drowned. Hawaii had plenty of warning from direct measurement, not looking at the sky.
Interesting stuff, but not very helpful.
Nowadays we are, quite legitimately, sceptical about findings originating from government funded research with any, even remote, connection to “climate science”. But I think it is appropriate to reserve judgment in this instance. If this line of research proves capable of improving tsunami warning capability there is the potential to save many, many lives.
If this is a ripple effect of the sea water ion content being moved rapidly enough to generate air glow by induction into the ionosphere, there will be a low frequency wave pulse that was able to extend its influence far enough ahead to alert wild animals as it passes through an hour ahead.
Then it should be possible to monitor the wave lengths that are generated, just like seismic wave patterns, and by comparison quantify the effects to expect from the Tsunami quake combo.
Wow…I love stuff like this.
Something like the proposed monitoring system would have been helpful in the aftermath of the big Indonesian quake. The tsunami-alert center in Hawaii wasn’t sure the quake had generated a tsunami, so it didn’t issue an alert until it was too late for most.
Careful reading of the article finds…
“a camera system based in Maui, Hawaii”
and…
“It preceded the tsunami by one hour”
Means, not the creation of the tsunami, but of it hitting Hawaii, and detecting that event 1 hour before it hit by detecting the signature in the airglow layer, by the camera at the location of interest and concern.
One use of this technology could be for early warning for locations with poor communications with the rest of the world. But is there such a place left in the world? At least a backup or secondary line of defence.
I note that the researchers refer to “The signature, caused by the March 11 earthquake …”.
Hmm, I wonder. Is it in fact a matter of (a) tectonic forces causing flexing piezoelectric rocks to generate regions of ionisation in the adjacent atmosphere, with the observed airglow effect, or might it be (b) incoming EM energy from the sun causing incidental ionisation at the same time as it flexes the piezoelectric rocks and triggers the quake?
Given Piers Corbyn’s apparent ability to forecast periods of higher earthquake activity by studying the sun and the Earth’s neighbourhood, (b) makes a lot of sense to me: there’s a lot more energy floating about outside our atmosphere than inside it. Has anyone investigated this possibility? Obviously, I’m not discounting effects from any other interactions (like the centimetre-scale ripples on the sea surface), but which way does the energy actually flow as the quake starts?
“As a tsunami moves across the ocean, it produces atmospheric gravity waves forced by centimeter-level surface undulations. The amplitude of the waves can reach several kilometers…”
I am guessing the gravity waves travel faster then the ocean wave?
If the air glow preceded the tsunami by one hour how can the signature be caused by atmos. gravity waves in turn produced by cm. level undulations in the sea?
The signature must precede the earthquake if their prose is accurate.
Earthquake Lights as a possible cause of the ionosphere phenomenon??
Surely what is being detected is like a “shock wave” travelling one hour ahead of the tsunami (not to confuse the tsunami(wall of water) with the cause of the tsunami. The warning time will depend on the distance the tsunami has to travel, if more than an hour away, some notice of it’s arrival will be possible.
So if the tsunami originates four hours away there will be three hours warning approx.
This is not something that will predict a tsunami occuring but will give notice of it”s arrival.
Science maybe coming to terms with reality, the inter connect between the sun the moon and the planets is profound, throw in the the rest of the Universe bombarding us and it becomes more complex. That a quite sun has been noted in history with increased volcanism and Earth tremors shows we are very effected. That strange lights are seen in the sky when Earth quakes occur is historic also. That the upper atmosphere glows is no surprise, the harmonic reverberations in the Earth and the magnetic field when volcanoes erupt and Earth quakes occur are governed by the same equations that are used to trigger atomic weapons. No surprise at all, let us hope that the information can be used to save lives, if they delve deep enough they will also be able to predict volcanic eruptions accurately and the reciprocal Earth quakes. This stuff has been known for decades yet science has had its head in the sand pretending their theories are totally correct like climate science.
I wonder if they got their idea from this http://arxiv.org/ftp/arxiv/papers/1105/1105.2841.pdf by Ouzounov et al which uses a lot of satellite information.
Steve T says: …
“So if the tsunami originates four hours away there will be three hours warning approx.”
If the tsunami travelled at 800 km/h from Japan, it would have taken about 8 hours. The tsunami was detected in Hawaii (or would have been) by the method in this article 1 hour before it hit, 7 hours after the event (the quake). Your math doesn’t add up.
Hmmm…reminds me of a song by Rush from G/P – “Distant Early Warning”
Hmmm…reminds me of a song by Rush from P/G – “Distant Early Warning”
Sorry – fixed
Ok, the Bear is not the sharpest cue in this particular rack, but this article fails make any sense.
Even if gravity waves travel at the same speed, C, of electromagnetic radiation generally (and we don’t know that they do, as we don’t actually know what causes gravity, so far as the Bear knows) isn’t the supposed measuring of an electromagnetic artefact of a mechanical wave disturbance (the actual tsunami) a rather indirect way of doing things?
And how could it `precede’ the actual wave? Seems like time travel is required.
Or have I been breathing in too much of that carbon gas?
Steve C says:
July 15, 2011 at 2:22 am
I think you got right idea.
http://www.vukcevic.talktalk.net/gms.htm
Seems there is a lot of confusion that is unnecessary here.
A tsunami wave is not only in the ocean but also in the atmosphere all the way up to the ionosphere and above.
A camera on Maui is looking toward the ionosphere on the horizon and picks up the disturbance of the atmospheric gravity wave caused by the tsunami which is directly below that disturbance. The slant range to the disturbance in the ionosphere will be considerable, but depends on the level of the ionized layer being disturbed and seen by the camera.
The tsunami will take around an hour to reach the camera position from the time the ionospheric disturbance caused by the atmospheric gravity wave is first visible on the horizon.
From a satellite the tsunami in the atmosphere will be visible directly above the tsunami in the ocean as the tsunami is a wave propagating in the ocean and the atmosphere.
@M.A.Vukcevic says:
July 15, 2011 at 12:19 am
You are right, it seems the other way around.