Aerial photograph near Black's Beach in Southern California showing the effect of offshore canyons on surfzone processes. Alongshore variations in wave height, caused by propagation over the canyons, result in variation of the surfzone width from about 150 m at the southern edge of the image to 100 m at the northern edge. The waves propagating at large oblique angles relative to the shoreline (thin arrows point to wave crests) are nearly perpendicular to the incident wave direction and may have reflected from the steep canyon walls (located offshore and south of the image). The complex, breaking-wave-driven circulation includes converging alongshore flows and sediment-laden, offshore-directed rip currents that extend well outside the surf zone (thick arrows).