Summary of Article: A massive marine volcano called Nishinoshima has erupted dozens of times south of Tokyo, spewing red-hot lava. If Nishinoshima’s rocky slopes collapse during an eruption, they could cause a deadly tsunami that would reach the Ogasawara islands in 20 minutes. Scientists are planning to give the islanders a robotic protector: an extremely expensive Wave Glider drone that harvests wave and solar energy to power itself for months. Geologist Hiroko Sugioka realized that a mobile system stationed near fault lines is simpler and cheaper than a permanent one. The key part of the system is the Vector TsunaMeter. This device detects changes in the water level. Salty ocean water is a good electrical conductor. As a tsunami moves through the Earth’s magnetic field, electric fields are generated, which induce secondary magnetic fields. The VTM correlates disturbances in these fields with pressure changes to detect how big a tsunami is and where it is headed. If it works, Japan might roll out a network of tsunami-spotting drones.
Here is a photo of the areas in Japan that are most affected by tsunamis. These areas could benefit from the water glider drone.
Check out this video to see detection systems that have been tried in the past!