(dramatic music)
There are powerful forces
that move along our beaches.
They pulse.
They flow.
Some can appear without warning,
turning an idyllic beach setting into scenes of chaos,
and panic.
They're masters of camouflage, often hiding tremendous power
within seemingly calm waters.
Here, they wait for the unsuspecting.
And there are many.
The majority of beach-goers can't recognize their danger.
(dramatic music)
I suddenly sensed that I was in a different situation,
that I had never anticipated before.
I mean, it was a surge or a current moving off the shore,
out away from the shore, which I did not expect.
It was like you were in a river.
I'd actually swam myself into a rip current,
without being aware of it.
(dramatic music)
Lou Armstrong was lucky to survive.
If it wasn't for the efforts of his wife,
and a stranger walking the beach,
he would have perished in the rip.
But what exactly is a rip current?
Australian Rob Brander, often called Dr. Rip,
is one of the world's leading experts on rip currents.
Well, let me tell you what rips are not.
They're not undertow, they won't pull you under,
because there's no such thing as an undertow.
They're not rip tides, because they're not a tide.
They're a current.
Powerful currents can appear on any beach
that has breaking waves, and Australia has a lot of beaches.
Almost 11,000.
Less than four percent of these beaches
are actually patrolled by life guards.
So, it's critical that all Australian beach-goers
have a good understanding of the hazards.
The same is true around the world,
including the United States, where more than 12,000 miles
of welcoming coastline creates a perfect storm for tragedy.
Panama City, Florida.
June, 2019.
This compelling footage shows how a group
of swimmers quickly become trapped in the overwhelming flow.
Along with emergency personnel, tenacious bystanders
form a human chain and just barely free the swimmers
from the clutches of death.
And this is far from an isolated incident.
(siren wailing)
Each year, more than 50,000 people are rescued
from rip currents.
But more than 100 drown, struggling to make it to shore.
Surprisingly, even along the Great Lakes,
nearly 300 swimmers have died in rip currents since 2010.
This summer alone, more than 30 swimmers have already
lost their lives on US beaches.
Dr. Rob Brander believes many of these tragic incidents
could have been avoided if people were able
to recognize the signs of an operating rip current.
The simplest way to describe rip currents
is that they're strong, narrow, seaward flowing currents
that extend from the shoreline
out beyond the breaking waves.
And they exist to bring all that extra water
that's coming in with the breaking waves back offshore.
And all of our recent research has shown
that rips are incredibly complex,
and they're much more unpredictable and dangerous
than we could ever have imagined.
(dramatic music)
The best way to spot a rip is to look for dark gaps.
Right behind me, we've got a nice rip,
it looks like a dark gap, almost like a road,
or a path going through the surf.
Now, over here it's a shallow sandbar,
the waves are breaking, all that whitewater is piling up
on the beach, it starts flowing along the beach,
in this deeper channel, then turns the corner,
and that's your rip.
To be able to form,
rip currents need breaking waves.
It's the spatial variation in the breaking waves,
normally caused by undulations in the sand beds,
that commonly begins in the process
of a rip current forming.
A flow develops that moves from the region
of intense wave-breaking, toward the region
of reduced or no wave-breaking inside the surf zone.
This flow is the pathway of least resistance
for the outgoing water.
Often, a perfect channel, just like a river of the sea.
The water flowing out along this channel is the rip current.
The most common type is a channelized rip.
These rips occupy deep channels between sand bars,
and they can stay in the same place for days,
weeks, and even months.
Then, there's boundary rips,
which are found against headlands and other structures,
reaching out into the ocean, like piers and jetties.
But one of the most dangerous and unpredictable rips
is the flash rip.
You can see the chopped up, messy whitewater
that's just gone out, and then it's just stopped.
And that's one common thing about these flash rips,
is they can suddenly occur anywhere
where there's suddenly been a large group of waves breaking
and it pushes the rip out, and then it disappears.
Rob is driven to understand more
about how these deadly currents operate.
To get inside the heart of rip currents,
Rob uses GPS technology.
These instruments are mobile devices called drifters,
and when placed in a rip current,
their onboard GPS units record data that helps Rob
and his team understand more about
what these currents are doing.
(waves crashing)
Over the last decade, these experiments have recorded
hundreds of hours of data, across multiple beaches,
and the research has revealed some astonishing information.
Data from the GPS drifters has revealed so much variation
about how rip currents actually flow.
And really, it's changed everything about what we thought
we knew about rip currents.
The drifter data shows enormous variations
in rip current flow patterns.
Sometimes the rip flow exits well beyond the surf zone,
in the deeper water.
Sometimes it recirculates within the surf zone,
but also that there's dramatic variations
in both flow speed and the direction,
in incredibly short periods of time.
The average rip current flows offshore at speeds
of about half a meter to one meter per second.
But they all have a tendency to pulse.
What that means is that suddenly the rip current
can just dramatically double its speed
in a matter of 30 seconds, and then you're talking
speeds of two meters per second,
which is literally Olympic swimming speeds.
(dramatic music)
For Rob, this information is critical
to helping him answer a key question:
what's the best way to get out of a rip current alive?
(splashing)
So one of the problems with rips, of course,
is no matter what you do, people will always get caught
in rips, and you have to tell them something
about what they should do.
And one of the traditional pieces of advice
that's been around for a long, long time is,
if you get caught in a rip, you should swim parallel
to the beach; it's been there for ages.
But is that true?
Is that one, single piece of advice gonna work
in all situations?
And what our research has shown is that no,
that's not true, and we've got to the point now,
through our experiments, is that we have a much better
understanding of what we should tell people to do
when they get stuck in a rip.
This understanding has come through
repeated experiments that required Rob
and his research team to swim in different rip currents,
with GPS attached to them.
And to compare the results back to the data collected
from the GPS drifters.
This training exercise explains how this is done.
We've got the beach here, this is the rip,
essentially going like that.
We're all gonna walk in together,
to about that spot there,
somebody's gonna swim parallel that way,
somebody's just gonna float,
and somebody's gonna swim against the rip,
back to the beach.
Typically, rip currents are about 10 to 50 meters wide,
and they can flow anywhere from 50 to 100 meters offshore,
normally, but we've measured rip currents
that have flown 400 meters offshore.
It's never a good idea to actually try and swim against
the flow of a rip current.
In most cases, these rip currents are faster
than most people can actually swim, so if you try
swimming against that, you're just not gonna make
any progress, whatsoever.
We've also seen in our experiments that rips
can pulse or accelerate in flow.
Swimming parallel to escape a rip can often work.
In many of our experiments,
there was a really high success rate
of getting out of the rip.
But it didn't always work.
And the reason for that is not all rip currents
flow straight, and a lot of rip currents are these
rotating eddies, that eddy flow will take you around
in the shallow water, where you can likely stand up,
and the waves are breaking,
and you can use those breaking waves
to get back to the beach and back to safety.
The problem is that the average time
for a rip current to recirculate you back into shallow water
can be on the order of a couple of minutes
to up to 10 minutes.
The other option to escape a rip is just to stay afloat.
And that makes sense, because you're conserving energy,
and you can still put your hand up to signal for help.
The problem is that if you stay afloat
in a rip current that actually flows well beyond
the surf zone, you're gonna get stuck out there,
and you only have two options.
One is that you're gonna get rescued,
or you've got a long swim one way along the beach,
and then back in.
And that's a long swim.
Rob's research has revealed that there's no
single escape strategy that's guaranteed to get you
out of a rip current.
Instead, you have options based on the conditions
and the behavior of the rip.
The one factor that we have total control over
may in fact be the key to our survival in any rip encounter.
It's really panic that's the biggest killer
when it comes to rips; rips don't drown you,
they don't pull you under, but panic,
panicking will drown you.
Panicking sets off a chemical chain reaction.
The nervous system floods the body with adrenaline.
Fatigue is taking over, as the swimmer scrambles
to stay above the water's surface.
Each intense effort leads to greater amounts
of lactic acid flooding the body.
Causing muscular shutdown.
In less than one minute, a life can be lost.
The golden rule is to never attempt
to swim against the current.
Remember to stay calm and focus on floating.
Just go with the current and raise your hand for help.
And if you see someone struggling,
always try to throw them a flotation device first,
before entering the water.
Otherwise, you both might drown.
(dramatic music)
Nearly all rip current tragedies could be avoided,
if people didn't place themselves in harm's way
to begin with.
Complacency, coupled with a lack of skills to identify
rip currents remains a critical beach safety issue
for people choosing to swim outside the lifeguard areas,
or on un-patrolled beaches.