Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


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.

Airglow waves captured by the Illinois imaging system over Hawaii. The red line represents the location of the ocean-level tsunami at the time of the image.

Airglow waves captured by the Illinois imaging system over Hawaii. The red line represents the location of the ocean-level tsunami at the time of the image.

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.

Jonathan MakelaMakela 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.”

Contact: Jonathan Makela, Department of Electrical and Computer Engineering, 217/265-9470.

Writer: Kim Gudeman, Coordinated Science Laboratory.

Jonathan J. Makela | EurekAlert!
Further information:

More articles from Earth Sciences:

nachricht UCI and NASA document accelerated glacier melting in West Antarctica
26.10.2016 | University of California - Irvine

nachricht Ice shelf vibrations cause unusual waves in Antarctic atmosphere
25.10.2016 | American Geophysical Union

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Steering a fusion plasma toward stability

28.10.2016 | Power and Electrical Engineering

Bioluminescent sensor causes brain cells to glow in the dark

28.10.2016 | Life Sciences

Activation of 2 genes linked to development of atherosclerosis

28.10.2016 | Life Sciences

More VideoLinks >>>