National Security in the Surf Zone

There is an obvious but often unspoken reason for studying how waves and currents behave on different coasts with different seafloor profiles: national security.

In the World War II era, the Navy and Marines were desperate for knowledge of how to make amphibious landings, and some novel coastal research was conducted as a result. Then the Cold War moved most naval research to the deep, where submarines and big ships played acoustic cat-and-mouse in the blue water.

As global threats and approaches to combat changes again, the Navy has renewed its interest in the coastline. In fact, the U.S. Office of Naval Research was one of the major sponsors of the Nearshore Canyon Experiment (NCEX). The experiment itself is pure, fundamental coastal research. But the lessons will surely have military applications.

Special forces such as the Navy Seals need to understand and predict the dynamics of waves and currents because any operation that involves crossing the surf zone is dangerous. Equipment used for reaching and crossing the beach may not operate safely, and landing troops slowed by the surf are more vulnerable. The price of misunderstanding waves or water depth is paid in human lives.

“If you were to invade La Jolla, for example, where would you want to land?” Elgar said of the divergent surf conditions in the region. “The Pacific Rim is chockablock with deep submarine canyons like the one in La Jolla. North Korea, for instance, has an offshore canyon system that is quite similar. If researchers can improve their knowledge of how the shape of the seafloor influences wave dynamics, it could be possible to predict the waves and currents along coasts in other countries, where field experiments like NCEX are impossible.”

Originally published: July 1, 2004