When a hollow wave breaks over shallow reef or sand, the proceeding impact can be huge. Air trapped within the wave rolls forward, and for a split second, a line of rings forms below the surface. To capture this image, I had to dive directly into and under the explosion.

North Beach, Wollongong, New South Wales
Canon 5D Mk II, Canon 15mm fisheye 2.8, 1/1000, f/5.0, ISO 800, Aquatech sport housing

by Warren Keelan