Scientists at a Tsunami Warning Center are called Watchstanders, but that doesn't mean they continually watch the world's oceans for evidence of tsunamis. Instead, their job requires first watching measurements of seismic energy, which is the energy released when rock suddenly breaks or moves within the earth.

These seismic events, including earthquakes and landslides, are what trigger tsunamis by lifting and moving large amounts of water. Knowing when an earthquake occurs is straightforward based on seismic measurements, but deciding if a particular seismic event could have triggered a tsunami takes a little more detective work.