More than one ocean motion determines tsunami size

Giant wave forecasts need to take into account horizontal motion on sloped seafloors

2011 tsunami visualized

OCEAN MOTION  The 2011 tsunami that devastated Japan (forecast shown) was fueled by both the horizontal and vertical motion of the seafloor, new research suggests. Darker colors represent higher waves. Black triangles mark tsunami-measuring buoys.

NOAA Center for Tsunami Research

Earthquake-powered shifts along the seafloor that push water forward, not just up, could help supersize tsunamis.