News Service from House Harris

NSW:Science of the surf - a ripping yarn

SYDNEY, AAP - Dr Rob Brander is one of the world's foremost authorities on rips and has made it his mission to campaign for surf safety and education.

But although he's been studying the subject for 15 years, on his first visit to an Australian beach in 1992 the Canadian-born academic couldn't spot one - no matter how hard he tried.

"I was at Bronte (in Sydney's eastern suburbs) with an Australian friend and it was my very first visit to an Australian beach," Dr Brander says of that beach visit 16 years ago.

"I'd been studying coastal geomorphology, which is about coastal processes back in Toronto, and had been reading all this stuff about rips, and my Australian friend was pointing out where the rip was and I couldn't see it.

"I kept looking, and no matter how hard I tried I just couldn't see it.

"It was a little bit unnerving, I had been reading up about rips and had this interest in the subject, and there I was and I just couldn't see it."

This experience motivated Dr Brander to return to Australia in 1993 to undertake a PhD on rips at University of Sydney. He also became a volunteer surf life saver at Sydney's most dangerous patrolled beach, Tamarama.

Known locally as "Glamourama", the beach is a favourite haunt for models, actors and celebrities.

It was there, a beach no more than 80-metres wide with two permanent rips at either end, that Dr Brander experienced first-hand how little knowledge the public had about rips or how to spot them before they entered the surf.

"We'd talk to people who were about to walk straight into a rip, or who had just been rescued in one.

"(We'd say) `do you know you were in a rip?' and they'd say `no'.

"Then we'd ask them do you know what a rip is? And they'd have no idea."

His passion for the subject has now earned him the moniker Dr Rip.

He has lectured at more than 100 schools and to some 10,000 people in NSW over the past 10 years through his award-winning Science of the Surf talks.

He says there are many myths about rips. For example, there's no such thing as an undertow, he says.

"Rips do not pull you under, they just take you for a big of a ride," he says.

According to Dr Brander, there is a misconception that sandbanks can collapse, washing people into rips.

"Sandbanks don't just collapse. The only way you could get a sandbank to collapse is to blow it up.

"What happens is that a set of larger waves comes in and brings in extra water, which causes the water level to rise when they break, and this extra water can temporarily accelerate the rip," he says.

Dr Brander says many drownings and 90 per cent of rescues are caused by rips, yet the typical beach user has no idea what a rip is.

At any given time it is estimated that 17,000 rips exist on Australia's 11,000 beaches, 97 per cent of which are not patrolled,.

Rips are strong, narrow, seaward flowing currents that extend from the shoreline through the surf zone and beyond.

They sit in channels and are a mechanism by which water brought to shore by breaking waves is taken back out to sea.

There are three main types of rips. The most common are low energy rips. These don't move much and are usually fixed in place. They sit in channels between sand bars when waves are smaller or haven't changed for a while.

Another type is the high energy or flash rip. These are bigger and much stronger and occur when waves increase suddenly, for example during a storm.

Dr Brander says flash rips occur when the rip channel can't cope with the additional water moving out to sea and the rip travels along the beach, popping up here and there.

Some rips, are permanent. These are usually squeezed up against headlands and exist almost all the time, like the so-called backpacker's express at the southern end of Sydney's Bondi beach.

Even a small rip can take you 100 metres offshore in less a minute, but most rips actually flow in a circular direction and will eventually take you back to shore.

A general rule of thumb is that the rip won't take you much further out than the seaward surf break.

Dr Brander says is vital that everyone visiting a beach understands how rips work and know how to spot one.

He believes surf safety should be compulsory in schools.

Dr Brandon says overseas visitors should also be made aware of rips through in-flight videos and a pamphlet when they arrive in the country.

He stresses the importance of swimming between the flags, which he says are there for a good reason.

"While swim between the flags is an important first step, the next step is to educate beach goers how to spot rips so as to avoid them, which is main reason whey the flags are placed where they are," he says.

He said a recent survey of about 1,000 people by the University of New South Wales and Surf Life Saving Australia found 80 per cent of people questioned said they thought they knew what a rip was, but when shown a photo of one only 50 per cent could correctly identify it.

Dr Brander says a public campaign similar to the successful Slip, Slap, Slop sun awareness initiative would help educate beach goers about rips. He is presently working with Surf Lifesaving Australia on their recent national campaign to reduce rip drownings and rescues and to improve education and awareness.

WHAT TO DO IF YOU ARE CAUGHT IN A RIP

*The most important thing is DON'T PANIC. The rip won't pull you under and drown you. It will just carry you seaward

*Do not swim against the ripe or else you will tire quickly. Either swim to the side, swim towards the white water or let it take you out to the back of the surf and signal for help.

*Don't get caught in rip in the first place. Make sure you understand what rips are and how to identify them. If you don't, make sure you always swim between the flags on patrolled beaches.

HOW TO SPOT A RIP

Rips usually sit in deeper channels between shallow sandbars, so the water always appears darker and waves don't break as much in the area of the rip. For this reason, the water surface of a rip often appears calm and inviting, one of the reasons why so many people accidentally swim in them.

Look out for persistent dark gaps, like paths, that extend through the surf zone and don't move for five or ten minutes.

Rips carry objects like water, seaweed and people. Look out for things moving in the current.

FACTS ABOUT RIPS

*Rips flow fastest around low tide.

*Rip flow increases, or pulses, in speed shortly after wave sets break.

*Strong rips flow faster than Olympic swimmers.