Identifying tsunamis in real time with observations of magnetic fields

Scientists have placed observatories throughout the Pacific Ocean to measure the Earth’s magnetic field. Ocean water also produces magnetic fields, weaker than Earth’s, but detectable with recently improved technologies. Manoj Nair and his team suspect they can learn to detect tsunami-related magnetic signals in oceans, which are often masked by small fluctuations in the Earth’s magnetic field. With support from a CIRES Innovative Research Proposal, Manoj Nair and his colleagues will try to peak under this mask. The investigators will monitor magnetic signals on two islands, Easter Island and Tahiti, and identify the commonalities between the magnetic signals on both islands. These commonalities represent the Earth’s magnetic field, which does not vary over space, and they can be subtracted from the total magnetic signals collected on both islands. The ocean magnetic signals, which are affected by local ocean dynamics, can be extracted from the remaining magnetic signals. Eventually, the researchers hope that by monitoring Earth and ocean magnetic signals, they will be able to identify tsunamis in real time to support warning systems.