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Are We Within Sight of Being Able To Predict Earthquakes? What Will It Take To Do That?

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Data from a French research satellite analyzed after the fact may have seen warning signs in the days just before the magnitude 7 earthquake that devastated Haiti on Jan. 12, 2010. The French DEMETER satellite, launched in 2004 to analyze the ionosphere and the upper atmosphere in the vicinity of earthquake zones, recorded significant changes in the ionosphere just days before the Haiti earthquake. However, the DEMETER satellite was shut down in December 2010, just at the point when this kind of research needs to be expanded dramatically, in order to gain a much better understanding of what happens inside the Earth’s crust before an earthquake and the disturbances that it causes in the upper atmosphere.

In a paper published last December, scientists from the University of Serres and the Democritus University of Thrace, both in Greece, reported that DEMETER recorded large variations in the electric field above the Earth, "a significant increase in energy" in the 30 days before the earthquake. "This result clearly indicates that the change in energy of ULF (ultra-low frequency — in the range of 0-20 hz) magnetic waves could be related to strong precursory earthquake phenomena." They write that theoretical studies and laboratory experiments suggest that the deformation of rocks under pressure and temperature conditions deep in the Earth’s crust change their electrical properties, which generates electrical charges that can be propagated into the atmosphere. These charges disturb the ionosphere and cause very-low-frequency emissions of electromagnetic waves. Regardless of the accuracy of this particular explanation, the results of the DEMETER satellite observations over Haiti "reveal a significant increase of the energy of ULF waves, up to 360%, for a period of one month before the main earthquake, compared with the energy of the background." These results "clearly indicate that ULF electromagnetic waves can be very useful in revealing possible precursor seismic phenomena in the ionosphere."

The DEMETER project team also reported similar phenomena preceding a magnitude 8 earthquake that hit Samoa in September 2009. Seven days prior to the earthquake, the satellite recorded "an increase in the densities and a decrease in the temperature (of the ionosphere) which are well localized above the future epicenter."

DEMETER was built on research in the 1990s that first found that changes in the Earth’s surface before major earthquakes disturb the ionosphere, 700 km above the Earth’s surface. A Jan. 24, 2010 article in Alaska’s Anchorage Daily News reported that researchers believe that the ionosphere, made up of negatively charged particles, is drawn downward as positive ions stream up from the Earth’s surface before a quake. DEMETER wasn’t the only such effort, however. A NASA satellite measuring the emission of infrared light from the Earth’s surface came up with similar results. Strong earthquakes are also preceded by marked infrared emissions.

The problem is that such research has been vastly underfunded generally. There are indications that it has even been hindered by the U.S. Geological Survey, which decides who gets earthquake research grants. USGS’s seismologists follow a mechanical model of earthquake hazard assessment, and the agency claims that no electromagnetic research has been shown to be "predictive to the satisfaction of the USGS and the seismological community." Critics accuse the USGS of a conflict of interest which leads it to steer grants to its existing seismological network.

Researchers at NASA have a different approach, however. Friedemann Freund, of NASA’s Ames Research Center, who has developed what is regarded as the most comprehensive seismo-electromagnetic theory, is confident that further advances in this area will make forecasts possible. "We will be able to give practical forecasts for all strong quakes, certainly 7.0, perhaps to 6.0," he said. "You will never know the exact day or the exact epicenter, just as you can never say exactly where lightning will strike. But you can say ’The storm is coming.’"