Oceanography

Tsunamis collide and grow taller

Journal name:
Nature
Volume:
483,
Page:
126
Date published:
DOI:
doi:10.1038/483126a
Published online

Ridges and mountains on the sea floor dangerously amplified the eastward-bound segments of the tsunami that devastated Japan's Tohoku coast (pictured) last year.

Satellite observations made on 11 March at different locations over the Pacific Ocean suggest that tsunami height increased as the wavefront raced towards the west coast of America. Tony Song at NASA's Jet Propulsion Laboratory in Pasadena, California, and his team compared satellite data with a tsunami simulation and maps of ocean-bottom topography. They conclude that topographic barriers such as the Hawaiian Ridge slowed and curved the eastward-bound tsunami front. As segments of this disrupted front collided and merged, the peak-to-trough height of the tsunami wave more than doubled.

Understanding how tsunamis interact with ocean-floor topography could help researchers to improve tsunami forecasting.

KYODO/REUTERS

Geophys. Res. Lett. http://dx.doi.org/10.1029/2011GL050767 (2012)

For more on the Japan earthquake, see http://www.nature.com/japanquake.

Additional data