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An Anatomy of Jeffreys Bay

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An Anatomy of Jeffreys Bay

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Words: Nick Carroll

Images: Alan Van Guysen

This article was from the pages of Surfing Life 331, where Ours and Puerto Escondido were both analysed in the same manner. Grab a copy now!

It’s just a wave, right? No, it’s never just a wave.

What we see happening in the surf zone, even at your little local beachie, is the result of complex natural processes that’ve been in train literally since the oceans began to form. Since volcanic eruptions millions of years ago, and sea level rises thousands of years ago, and sand movements last century, and storms and winds just days or hours old. These processes and the waves they form seem so much bigger and longer-ranging than anything we humans have managed – they dwarf our attempts to replicate them in pools, for instance. But they’re also very much in the here and now, breaking at this very moment on reef or sand, real and truly renewable – the best part of our surfing lives.

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SL reckons they’re worth understanding. So let’s have a look at Jeffreys Bay.

The wave that fired dreams among every surfer who first saw it blown up on the big screen back in the late 1970s; who saw Occy tearing it up in the 1980s, and Curren Searching it in the 1990s. Jeffreys Bay is the spot the ‘Endless Summer’ missed, but the hardcore South African surf community didn’t. Its crazy-long windblown lineup and lengthy series of sections, from Kitchen Windows way up top to Albatross way down the inside, was perfectly suited to a style of surfing that arose with the first modern hi-performance boards and surfers of the ’70s. That’s its history in a very small nutshell – but why is it great?

OFFSHORE

A heap is going on in the ocean off southern Africa. Indeed, not far south-west of J-Bay, two oceans – the Southern Indian and the South Atlantic – pretty much crash into each other. At the same time, a huge warm-water flow known as the Agulhas Current runs down the east African coast, creating eddies as it rubs up against the continental shelf between 20 and 60 kilometres out. The Agulhas curls as it travels outside J-Bay and strikes an elevated area of continental shelf known as the Agulhas Bank, helping create an incredibly fecund sea-life environment, rich with squid, whales and many other life forms – part of why Jeffreys is originally a fishing town. And also part of why Mick Fanning had that encounter last July.

Thanks to the Agulhas Bank, the continental shelf slopes slightly more NE/SW than the actual coastline, which affects the approach of very long-interval swells, but not that of shorter-interval, localised swells, which may show in outer waters but fail to penetrate the tucked-in J-Bay lineup. Some refraction occurs off a deep-water rise or bombie area a few k’s outside and to the SW of the break.

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INSHORE

The Jeffreys coastline has a lava rock base associated with mountain ranges some way inland. Volcanic rock is one of the classic bases for great surf spots worldwide, since it’s slow to erode and tends to form in strips and triangular lines – something you can clearly see both from a pulled-back perspective at Jeffreys, and from close up, when you’re making your way out through the crevices along the rim of the point. Fact is, J-Bay’s structure makes it as much a reef as a point; sections of the wave are smoothed by shifting sand deposits that flow up the coast from beyond the neighbouring Cape St Francis, and fill the worn-away lava crevices. Sand can also be pushed back up the point in easterly winds and swells that sweep down its huge flanking open beach. (Excellent beach breaks down here, by the way.)

The point itself is on a dramatic angle to the general run of the coast; it’s almost like a short strip of east coast, facing away from much of the direct swell source (see below). But it also means that the strong SW winds that often accompany its best swells blow cleanly offshore, assisted by the wall of mountains inland. At other times, those same mountains can contribute to the NNW ‘devil winds’ that can plague the break for days – though other lesser spots in the area love those winds.

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SWELL CREATORS

South and west of J-Bay, deep lows arise from the Roaring Forties as they begin the long gale line toward Western Australia. These lows drive up against persistent temperate high pressure in the South Atlantic and form long fetches of SW winds angling up toward the southern African coastline. Occasionally these winds develop enough strength and consistency to form a very long interval SW groundswell, which can refract off the rim of the continental shelf and bend enough to push into Jeffreys. To get a picture of this, it’s important to grasp how deep a swell’s energy can move underwater. A 20-second interval groundswell, for instance, can feel the ocean floor at around 300 metres – pretty much the depth of the first part of the shelf. Such a swell will ‘drag’ on the ocean floor and bend toward the coast a lot earlier than a shorter-interval swell.

So J-Bay might catch a bit of that. But its favourite direction is SSW: off lows that move to a point almost dead south of Africa and not a hell of a way offshore. These storms and their associated winds will push a swell more directly toward the angled J-Bay lineup, and the swell’s bend across the shelf will enhance that angle, bringing lines in at around 30 degrees to the reef line and putting a slight bowl onto the wave. That’s when you’ll see Supertubes – the magical second section – barrelling off its face. It’s also a hell of a lot more consistent.

These storms tend to occur more in the autumn and winter months – they also propagate into the Indian Ocean and thus hit Indonesia, which is why J-Bay’s and Indo’s seasons match up. But by no means is that the only time such storms will form; some summers, Jeffreys is epic.

A third swell source comes off SE winds formed by temperate highs drifting south of Africa – sort of a dislocated tradewind effect. These swells get all the way in to J-Bay, but are often a bit steep in the angle, causing the spot to section out.

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RELIABILITY/THE FUTURE

J-Bay breaks a lot; brilliantly, less so. Thanks to its exceptionally tucked-in angle and limited exposure, months can pass without conditions clicking to provide swell and good winds together. But it can be accurately forecast several days ahead of time, thanks to the weather dynamics in the South Atlantic and Southern Indian Oceans, and thanks to the settling effect of the African continent – landmasses help make weather more predictable. (There’s a number of travelling J-Bay aficionados who’ve learned to time international flights to the forecast.) It is also likely to cope well with future sea level rises, thanks to its solid lava-rock foundations and sand cushion, which will help it absorb wave energy over time.

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