Tsunami — a killer wave — speeding across
the ocean at 400 miles an hour. It smashes into land destroying everything
in its path. Tsunamis do not have a season. But they can strike any coast at any time. If one forms close to the shore, the shaking of the earth and a loud roar may warn of its approach. But when a tsunami forms across the ocean, it can take hours to reach the shore — enough time to warn people to move to higher land. Over the past twenty years, NOAA has developed
DART: a real-time monitoring system that provides data for forecasting tsunamis. The DART systems
have been deployed in earthquake prone areas throughout the ocean, including the Pacific
and Indian basins. A DART system combinesa surface buoy and a sensor on the ocean floor. This sensor detects changes in water pressure and seismic activity and transmits the data back to the surface. If these changes indicate a tsunami may form, the buoy signals an alert via satellite to the Tsunami Warning Centers in Alaska and Hawaii. Back at the Centers, scientists plug the data into pre-existing models. These models predict the height, the arrival time, and the coastal locations that the tsunami will hit. Watches and warnings are issued to the affected communities so preparations can begin. Today, 47 DART stations are positioned all
around the world ready to detect and warn coastal communities about the next potential tsunami. With the DART system and Tsunami Warning Centers in place, we are now better prepared to predict a killer wave before it strikes.