Hawaii surfing team members Garrett McNamara and Kealii Mamala become the first - and possibly last - surfers to successfully ride glacier-generated tsunami waves of up to 25 feet in 2007 in Cordove, Alaska. Their tsunami surfing experience took place at Child's Glacier on the Copper River. Team members rode waves generated when large ice faces calved away from the glacier

Photograph: Bo Bridges/Polaris