On December 26, 2004, a series of devastating waves attacked coastlines all around the Indian Ocean, taking the largest toll of any tsunami ever recorded. The surges decimated entire cities and villages, killing more than 225,000 people within a matter of hours and leaving at least a million homeless.
This shocking disaster underscored an important fact: as populations boom in coastal regions worldwide, tsunamis pose a greater risk than ever before. At the same time, this tsunami was the best documented in history--opening a unique opportunity to learn how to avoid such catastrophes in the future. From home videos of muddy water engulfing seaside hotels to satellite measurements of the waves propagating across the open ocean, the massive influx of information has reshaped what scientists know in several ways.