Predicting earthquakes and tsunamis with fibre-optic networks

Geophysicists at ETH Zurich have shown that every single wave of a magnitude 3.9 earthquake registers in the noise suppression system of fibre-optic networks. This method can be used to set up close-meshed earthquake and tsunami early warning systems at low cost. For wealthy countries like Switzerland, having a dense network of earthquake monitoring stations is a matter of course [AF1] . This is not the case in less developed countries and on the floor of the world's oceans. While poorer regions lack the money for the necessary number of sensors, the oceans require complex systems that can reliably measure minimal pressure changes at depths of thousands of metres and bring the data signals to the surface. Secondary use of noise suppression data Scientists from the Institute of Geophysics at ETH Zurich, working together with the Swiss Federal Institute of Metrology (METAS), have now found an amazing and inexpensive method that enables accurate earthquake measurements even on the ocean floor and in less developed countries. "We're taking advantage of a function that existing fibre-optic infrastructure already performs: we obtain the vibration data from the active noise suppression system, which has the job of increasing the accuracy of the signals in optical data communication," explains geophysics professor Andreas Fichtner.