March 2022 (ROTM #159) South-West France
It’s time to breakaway from the south-east coast of Australia, where most of the Rip of the Month pictures have come from the last few years, and go somewhere exotic – like south-west France. A bit of travelling is good!
My friend, colleague and rip current scientist extraordinaire (and generally amazing coastal scientist) Bruno Castelle from the University of Bordeaux posted this picture (and another fantastic one) on his Twitter feed recently and it’s a spectacular image of some fairly remote coastline in the Nouvelle- Aquitaine region along the Atlantic Coast of France, to the north-west of Bordeaux. The image is courtesy of the Observatoire de la Côte de Nouvelle-Acquitaine
It’s a beautiful section of coast that is backed by sand dunes and experiences meso-macro tide ranges of up to 5 m with good surfing and well-developed rip currents, typically about 400 m apart. It’s mostly popular with holiday camping in the summer months.
These (channel) rips are amazing. You can clearly see that they occupy deep channels between the sandbars that are connected to the beach and have carved out their own embayments. Perhaps more impressive is just how far offshore the rip flow extends. What’s also interesting is that for some of the rips, the flow is very narrow until the rip current flow slows down and decelerates into an expanding rip head. You can see the plumes of sediment that have been carried by the rip flow. If you have a keen eye, you can also see that the waves are approaching the beach at an angle from the north (the picture is facing south-west) and that is causing some of the rip flow to be directed offshore at the southern end of the rip channels, particularly for the rips in the upper half of the photo.
Bruno and some his colleagues are about to conduct a large experiment this summer with a beach safety focus looking at both physical aspects of rip currents and social aspects, including surveys of beachgoers led by Jeoffrey Dehez (@DehezJeoffrey on Twitter). Stay tuned!
French beaches (and rips) don’t get the credit they deserve