Though observational networks exist to provide warning of an impending tsunami, Foster et al. propose a way to improve observational ability at a relatively low cost compared to ramping up the use of existing techniques. Triggered by shallow subaquatic earthquakes or eruption of an ocean floor volcano, tsunamis are nearly imperceptible waves in the open ocean but can grow to extreme heights near the shore. Currently the existence of a tsunami is initially determined by analyzing the wave-generating event itself, where earthquakes or eruptions fitting a specific depth and strength profile are considered tsunami generating. After a tsunami-generating event is detected, a sparse network of seafloor-mounted sensors tracks the propagating waves.