Australasian Science: Australia's authority on science since 1938

Green Is Mean and White Is Nice

By Stephen Luntz

Public understanding of rip research is saving Australian lives each summer.

The man who has done the most to educate Australians about dangers lurking off our coasts grew up in icy Canada, completing his undergraduate and Masters degrees at the University of Toronto.

Dr Rob Brander has made great strides in unlocking the behaviour of rip currents on Australian beaches, but has made an even greater contribution to safety through his efforts to teach beach-goers safe swimming.

“I always liked working in the outdoors,” says Brander. “At school I gravitated to geomorphology. I thought I would end up studying mountains and glaciers. However, I was inspired by a lecturer who was studying the coasts of the Great Lakes.”

Brander did his Masters on sediment transport in the Lakes. Visiting Australia, a friend pointed out a rip at a beach. “I couldn’t see it,” Brander says. “And I’d been studying rips. I got interested and this became my PhD.”

After completing his doctorate at the University of Sydney, Brander spent 3 years in New Zealand before landing a position at his current home in the School of Biological, Earth and Environmental Sciences at the University of NSW.

Rips were difficult targets in the mid-90s. “We used current meters mounted on heavy transport. We had to walk them into the surf at low tide, and retrieve them again at next low tide,” he says. This equipment is still in use, providing detailed information about the flow at a particular point. But with just three machines to use, sampling an entire beach is limited.

Now Brander relies more on GPS drifters that float in the current and provide frequent information about their position. Thirty of these scattered across a beach provide a map of current flows.

American studies have challenged ideas about how rips work. “The traditional paradigm was that water enters the rip from side longshore feeder currents and flows straight offshore well beyond breaking waves,” says Bander. “This had big implications for beach safety. The obvious thing was to swim parallel to the beach to get out of the rip before ending up too far offshore.”

While this is still widely taught, Bander says: “New techniques show that rips sometimes form tight circles within the surf zone”. In such circumstances it is better to just float, as one can end up washed onto a sandbar. US studies have found this applies to 80% of rips. Brander is applying the same techniques to see if similar conclusions can be reached here.

Before Brander entered the field, education campaigns focused on escaping rips, but even before the complexities emerged Brander thought it better to help people avoid rips altogether. “We did studies of beachgoers showing them beach photographs and asking if they could identify a rip. We found 60% couldn’t and in fact more than half, when asked where they would swim, pointed straight to the rip.”

These figures, at least in NSW, have changed dramatically in just f5 years, in large part as a result of Brander’s work. “I started doing talks about the science of surf and I had people saying, ‘I lived on the beach all my life and never knew this,’” says Brander. Word spread and Brander found himself giving talks in coastal towns to packed rooms of 100–150 people.

From this emerged Dr Rip’s Essential Beach Book and www.scienceofthesurf.com. The site’s most popular video has had 300,000 views, and Brander says it is shown in schools up and down the coast. “Green is mean,” Brander summarises. “White is nice. Look out for patches of dark green water flowing through gaps in the surf.”

Brander’s educational work has won him several community safety awards and the 2012 Eureka Prize for Promoting Understanding of Australian Science Research. However, for a period he struggled to get funding for his rip research and turned to investigating the effects of waves on coral islands.

The work took him to the Maldives and Torres Strait, among other places, where he learned that even small cays are “surprisingly robust”. Erosion from waves and currents can eat away at habitation built too close to the shore, but the island can adjust by growing in another direction.

He is back to concentrating on rips, however. “A job that takes you outside working on beaches is hard to beat,” says Brander. “I don’t even think of it as a job.”