Excerpt:
Gigantic tsunamis have been decimating coastlines since time immemorial. We ignore these prehistoric warnings at our own peril.
A boulder weighing more than 40 tonnes sits on the sand high above the ocean. Dwarfing every other rock in view, it is conspicuously out of place. The answer to how this massive outlier got here lies not in the vast expanse of the Atacama Desert behind it but in the Pacific Ocean below. Hundreds of years ago, a tsunami slammed into the northern Chilean coast—a wall of water 20 meters high, taller than a six-story building, that swept boulders landward like pebbles.
The tsunami that lobbed this behemoth happened before written records existed in Chile. But we know about it today thanks to the detective work of a small group of researchers who are uncovering the signs of ancient tsunamis around the globe. Using a diverse array of scientific techniques, these paleotsunami researchers have found evidence of previously undocumented colossal waves. In the process, their work is revealing that coastal communities could be in far more danger from tsunamis than they realize.
As scientists expand their search, they have continued to find ancient tsunamis bigger than those found in historical records, says James Goff, a paleotsunami researcher at the University of Southampton in England. The implications are clear: if a huge tsunami happened once in a given location, it could happen again. The question is whether we’re prepared for it…
