Anyone who has seen videos of the tsunami that hit Japan in 2011, killing 20,000 Japanese and costing $300 billion, or the Indian Ocean tsunami in 2004 that killed 230,000 and cost $15 billion, knows and is afraid of the awesome power of nature, especially oceans. These two tsunamis are now considered the most destructive tsunamis in over 400 years.
As the videos above show, many people who live in areas vulnerable to tsunamis rarely have more than 15 minutes to find high ground. The great irony of these recent events is that historic records show tsunamis have devastated these areas before and will do so again. But humans, shortsighted by nature, disregard this information and build structures in vulnerable areas.
New Warning Systems Use Networks of Sensors & Buoys
Now, oceanographers and scientists are developing and testing new theories of deep-ocean sound waves to help detect tsunamis more quickly, saving lives, if not property. One product of this inquiry is DART or Deep-Ocean Assessment and Reporting for tsunamis.
A New Field of Oceanography
A new book, “Tsunamis: Detection, Monitoring, and Early-Warning Technologies” by Antony Joseph, is a reference guide providing a global perspective on the current state of tsunami detection technology. The book is intended as a resource for oceanographers and marine engineers whose job is to integrate tsunami warning systems into projects of various kinds. According to Joseph, there are two main types of tsunami warning systems (TWS): international and regional. Both systems could benefit from tsunami detection technology.
Tsunami waves create small but measurable changes in water pressure for up to 20 minutes. Using subsea transponders that use wideband acoustic signal technology, alarms can be triggered and messages sent via buoys on the ocean surface. These messages are relayed via satellite data links to on land control centers that can issue warnings to threatened communities.
The following video by the National Oceanographic & Atmospheric Administration’s (NOAA) National Ocean Service shows killer waves speeding across the ocean at 400 mph and discusses how they might be detected.