Hobbies And Interests
Deep Sea Radar
Ocean radar technology is one of the newest methods of tracking tsunamis after major seismic events at sea. The massive 2011 earthquake that struck Japan measured 9.0 on the Richter scale and was the first major quake to be tracked by ocean radar. Radar gives a faster, more accurate reading of a tsunami's size, speed and direction than older methods, so its introduction marks a step forward in tsunami warnings. Ocean radar uses high-frequency radio waves that track the movements of water more precisely than the microwaves used by traditional radar.
Tide Gauges
Tide gauges are primarily used to measure tides at shorelines around the world. They measure the height of the ocean's surface by way of an acoustic sensor, which emits a pulse through a vertical tube in the water's surface and records the distance to the surface of the water based on the time it takes the sound signal to return to the sensor. Since they measure changes in the height of the sea surface, they also are effective in measuring the height of oncoming tsunamis.
Satellites
The Indian Ocean tsunami that devastated South Asia in December 2004 was first picked up by a satellite altimeter passing over the area. Satellites use electromagnetic pulses to measure the height of the ocean's surface and report on possible tsunamis, though the speed at which tsunamis travel makes them difficult to capture on satellite. The altimeter may pass over a particular area only once a month or so and essentially needs to be in the right position at exactly the right time to catch a tsunami before it hits shore.
The DART System
The Deep-Ocean Assessment and Reporting of Tsunamis system, known as DART, uses pressure gauges on the ocean floor that register when a tsunami passes over. This network of sensors and reporting stations then relays the information to the Pacific Tsunami Warning Center by satellite. If necessary, tsunami warnings are then issued to affected areas.