Magnetic Fields Can Act As Early Warning Signs For Tsunamis

Scientists are now investigating how to predict tsunamis, and are showing how the magnetic fields generated by tsunamis can be detected before the devastating waves make it to shore. It was known that tsunamis generate magnetic fields as they cause massive shifts in conductive seawater, and previous research has indicated that this magnetic field takes shape ahead of the dramatic and dangerous changes in sea level.

What has remained unclear was the distinct relationship between the two, with research lacking measurements of the magnetic field and associated sea level changes needed to demonstrate the precise connection.

By looking into data from the 2009 tsunami in Samoa and 2010 tsunami in Chile, the authors of a new study claim to have connected the dots.

This data provided the scientists with the necessary information to compare the magnetic fields generated by the tsunamis with the resulting changes in sea level, which indeed confirmed that the former took shape before the latter.

How much earlier the magnetic field arrived depended on how deep the water was, but at a depth of 4,800 meters, the scientists found it arrived around a minute ahead of the changes in sea level.

“We have observations of sea level change, and we find that the observation agrees with our magnetic data as well as theoretical simulation.”

“We’ve needed a study that compared the magnetic field data with the sea level change from the pressure data, and I’m pretty sure they’re the first to really compare how well the sea level from magnetic field matches the sea level from pressure, so that’s definitely very useful.”