How to better predict tsunamis? We’re using GPS and other global navigation satellite systems to detect, in real time, changes in the ionosphere, the atmosphere located from about 50 to 621 miles (80 to 1,000 kilometers) above Earth’s surface. When a tsunami forms and moves across the ocean, the crests and troughs of its waves compress and extend the air above them, creating motions in the atmosphere known as internal gravity waves. Learn more: https://www.nasa.gov/feature/jpl/scientists-look-to-skies-to-improve-tsunami-detection
