Currents Cited for Big Waves at Surfing Spot

A 2 1/2-month study has helped uncover why a stretch of San Diego coast known as Black’s Beach has waves that attract surfers and are a hazard for inexperienced swimmers.

Researchers using a plane, a ship and instruments floating in the water and anchored to the sea floor have found that Black’s Beach is a jumble of rip currents, swirling eddies and crossing swells that can produce powerful A-frame-shaped waves.

“The currents there are the most complex I’ve seen anywhere,” said Robert T. Guza, a research professor at Scripps Institution of Oceanography.

Currents running near the shore along most stretches of the coastline may head in one direction, while those at Black’s move in the opposite direction, Guza said. There are also strong rip currents, which pull streams of sea water out into the ocean and can be dangerous for swimmers.