Identifying Rip Currents (IMAGE) University of New South Wales Caption Purple dye indicating the presence of a rip current at Tamarama Beach in Sydney, Australia. The technique is used by UNSW Associate Professor Rob Brander to educate swimmers about beach safety. Credit UNSW Usage Restrictions With appropriate caption and credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.