The turmoil under your keel
STANFORD, California _ Researchers at the Stanford Woods Institute for the Environment have discovered a deep ocean “surf zone” where waves can travel for hundreds of kilometers _ just like those at the surface. The undersea waves occur in areas 500 meters deep in between layers of water of different salinity and temperature.
The existence of sub-surface waves in itself was known. Stanford researchers Leif Thomas and Dan Whitt developed a mathematical model that gives new insights into how these waves propagate in the ocean when currents of waters of different density clash.
In a recent paper, the 2 researchers say that when deep ocean waves hit a current with a different density, they slow down and break. Just like surface waves break over shallows. “Strong ocean currents such as the Gulf Stream present ideal conditions for internal wave breaking,” Thomas said. “We basically discovered a surf zone for these wind-driven internal waves.” The Gulfstream that brushes past North America and Western Europe exhibits “enhanced turbulence” where sub-polar currents and subtropical currents meet.