Rare and wonderful, the green flash is a phenomenon that occurs as the sun sets into the sea. For a technical explanation of why this happens, here's a link to the Wikipedia article.

Whenever I'm "out west" around sunset, I hope to see a green flash, but am rarely lucky enough to catch one. This shot was among the first I made with my then new "big boy" camera, the Canon 5D Mark 2 back in 2009.