The deadly wave that shook the world on Dec. 26, 2004 caused the deaths of more than 280,000 people. Triggered by one of the greatest earthquakes ever measured, the tsunami caught everyone by surprise and mystified scientists.

Deep below the surface of the sea lay vital clues to what happened. America's Tsunami: Are We Next? follows an international team of scientists for 17 days as they use remotely operated vehicles (ROVs) to explore the raw power of the earthquake through what it left behind on the ocean floor.

In May 2005, led by Dr. Kate Moran from the University of Rhode Island, the team of 27 top scientists quickly mobilized to re-create the chain of events by surveying the quake's underwater epicenter. Using state-of-the-art camera equipment, the scientific team gives viewers a never-before-seen look at the massive and dramatic geologic changes that caused overwhelming amounts of ocean water to be displaced in gigantic waves.

Compelling new geological evidence uncovered on the expedition proves that seafloor uplift from the 9.2 magnitude earthquake – not a giant underwater landslide as previously thought —caused the devastating Asian tsunami. The groundbreaking Indian Ocean seafloor expedition and scientific findings documented in the program also allowed scientists to improve computer-generated tsunami wave models and better predict the potential for tsunami wave damage.

In particular, scientists point to the northwest region of the U.S. (Northern California and coastal areas of Oregon and Washington) as being most at risk for a tsunami event. They predict that tsunamis happen every 300-400 years on the West Coast — the last on Jan. 26, 1700. With a fault line located just 50 miles off the coast along the Cascadia Subduction Zone, another tsunami could occur at any time.

Cascadia extends from Northern California to the peninsula of British Columbia and is a geological mirror image to the Indian Ocean subduction zone where the Dec. 2004 tsunami occurred. Using new data and improved models from the expedition, scientists predict a tsunami three times the size of current estimates could strike our northwestern coast.