Here we see a #bubble ring—which is like a smoke ring, but with #water—breaking the surface. Both bubble rings and smoke rings, also known as toroidal vortices, are formed when fluid is pulsed through a restrictive gap of some kind. In the #ocean, many #whales and dolphins have been observed blowing bubble rings and playing with them. #PhotoOfTheDay #ripples #lake #h2o #science #earth