April 2016 (ROTM#88) Stanwell Park, NSW, Australia

Back to my local stomping ground again for this months picture. I took this shot from a viewpoint called Bald Hill. It's known for its' amazing vistas and as a jump off point for hangliders, but it also provides an amazing birds eye view of rip currents. A research camera installed here monitoring rip behaviour every day would be fantastic.

There was a fairly big debate a few years ago about whether rips re-circulate within the surf zone (area of breaking waves) without going far offshore or whether they flow well beyond the breaking waves. Well, the truth is that they do both. But perhaps not always as far as the rip in this picture. Can you see it?

 Right in the middle of the photo is a plume of murky water heading out from the whitewater, literally like a narrow road, before it slows down and expands in what we call a 'rip head'. But it's a  LONG way offshore and the waves weren't even that big. So what's happened? I can't be sure, but I expect a large group of waves (called a wave set) came in, broke, added extra water which piled up and the rip suddenly accelerated offshore. It's called a rip pulse and it only lasts for a minute or less.

 The interesting thing about this picture is that the plume is heading offshore just offset of a noticeable dark gap rip current channel just below it. You'd expect the rip flow to come right out of the rip channel, but it hasn't. This could be more evidence that wave sets created a rip pulse. Or it could be that rip currents are still very complex and there is much we still don't understand!  But one thing is for sure. Staying afloat in the hope that the rip would re-circulate you back to the beach wouldn't have been a good strategy in this rip!

That rip plume is a LONG way offshore!