Phys.org December 21, 2021
The motion of conductive seawater by tsunamis can generate magnetic fields in the presence of the background geomagnetic main field. Previous studies found that, using the tsunami-generated seafloor magnetic field, it is possible to predict the propagation direction and wave height prior to the actual arrivals of tsunamis. In this study researchers in Japan correlate the tsunami magnetic field and the tsunami sea level change using observed data and three-dimensional simulations of the 2009 Samoa and 2010 Chile tsunamis. Their direct comparison of the tsunami observed magnetic field and tsunami sea level change illustrated that the vertical tsunami magnetic component arrived earlier than the sea level change. The “initial rise” signal in the observed horizontal tsunami magnetic component arrived even earlier was found by combing the observation with the three-dimensional simulations. They examined the precision of conversion of the tsunami magnetic field to the sea level change and found that the magnetic field derived tsunami sea levels were as precise as those obtained from differential pressure gauge data…read more. Open Access TECHNICAL ARTICLE
