The 3,000km Wave

Tony Butt

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Updated 286d ago

A few years ago, if you rode 20-foot waves at Waimea you could proudly call yourself a big wave surfer. But over the years people have been steadily nudging those numbers upwards, and, nowadays, if you don’t surf 40-foot waves at Jaws or Maverick's, you can’t seriously consider yourself a ‘real’ big wave rider. And it goes on. Every year somebody surfs a bigger wave. If you include tow surfing at Nazaré, an entire culture has grown up around how big somebody’s wave was compared with somebody else’s.

But what if I told you that there is a place in the world where the waves are so big that Nazaré, Cortes Bank or the biggest Jaws you’ve ever seen wouldn’t even register on the dial? These waves are ridden once or twice a year by a dedicated crew of riders who wait for the right conditions and then travel thousands of kilometres to get there.

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The reason you have never heard of these waves is that they travel through the air, not the water. They are called atmospheric internal solitary waves, or, more commonly, morning glory waves. They can have heights of over 1,000 metres (more than 3,000 feet) and the whole deal of chasing and riding them has an uncanny resemblance to what we think of as big wave surfing.

The vehicle of choice is usually a glider or hang-glider. All sorts of manoeuvres are possible including climbing and dropping, off-the-tops and cutbacks, all at around 150km per hour. Rides can be several hundred kilometres long. For example, in 2012, glider pilot Geoff Pratt surfed a morning glory for over 600 km, and was ‘up and riding’ for several hours.

Morning glory waves are produced by the convergence of the easterly trades and the sea breeze either side of the Cape York Peninsula, and then each wave is subsequently blown across into the Gulf of Carpentaria by the easterly trades.

Morning glory waves are produced by the convergence of the easterly trades and the sea breeze either side of the Cape York Peninsula, and then each wave is subsequently blown across into the Gulf of Carpentaria by the easterly trades.

Morning glory waves exist in various parts of the world, and can form at virtually any altitude. They are usually extremely difficult to predict and are mostly invisible. The only place that they occur on a more or less predictable basis and where they can be seen is around the York Peninsula and the Gulf of Carpentaria in Northern Queensland, Australia. Even here, they are invisible much of the time; but for a short period at the beginning of the wet season there is enough humidity in the air to transform them into giant rolling clouds. It is only during this short time every year – September and October – that these waves can be ridden. Most riders spend several days towing their gliders up to 3000km through the outback for the once-a-year opportunity of catching two or three waves. If you like surfing big waves, I’m sure that will sound familiar

In many ways they are very similar to ocean surface waves. Their arrival time, just like an ocean swell, is difficult to predict. Their exact height and distance apart, and the number of waves in a set, are not known for certain until the waves actually arrive. And as they hit the coast and begin to propagate over the land, the landforms beneath them selectively slow down different parts of the wave, resulting in a bending and warping of the wave – just like the way the ocean floor steers an ocean wave as it propagates into shallow water.

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The mechanisms responsible for the formation of morning glory waves are still not well understood by scientists. But a couple of theories have been proposed, one of which is the following; the land-mass of the York Peninsula heats up during the day, sucking in strong sea breezes either side of the peninsula late in the afternoon. Meanwhile, easterly trade winds continually to blow on the east side of the peninsula. The inrushing air from either side collides during the late evening and early night, causing a series of shockwaves in the atmosphere. As the sea breeze dies down during the night and early hours of the morning, the trade winds dominate. As a result, the shockwaves are blown south-westwards across the peninsula and into the Gulf of Carpentaria.

The waves arrive near the coast around dawn – hence the term ‘morning glory’. The only town within hundreds of kilometres in this vast area of salt flats and mangrove swamps is Burketown, 30km inland from the southeast corner of the Gulf of Carpentaria. Burketown is where the riders gather every year, and where they take off and land. With luck, the wave will pass near enough to Burketown and not veer off too far to the west. If it doesn’t pass within about 200km, it will be over the horizon and nobody will ever know it existed.

As a morning glory wave travels across the sky, it forces the air in front of it upwards, cooling the air and squeezing the water vapour out to form cloud. The air motion is just like the water motion on the front face of a surfing wave. The air then flows over the top of the wave and down the back, creating a huge turbulent downdraft which warms and dries as it descends, sharply vaporising any remaining cloud in its trail. In just the same way as a rider surfs an ocean wave, the rider of a morning glory is kept aloft by the giant updraft at the front of the wave.

Morning glory surfing is dangerous. If you are overtaken by the wave and end up sliding down the back, the downdraft and turbulence will probably shake your aircraft to bits or slam you into the ground. This part of Australia is one of the most isolated places on Earth, with no water, no shade and thousands of square kilometres of dry, featureless ground. The only place you can find water is around the crocodile-infested rivers. So you really don’t want to wipe out.

Morning glories were first surfed in 1989, and the number of people who have ridden them since is still remarkably few. They occur in such an isolated location and during such a limited period of time that big investments in time, money and effort are required. Most riders spend several days towing their gliders up to 3000km through the outback for the once-a-year opportunity of catching two or three waves. If you like surfing big waves, I’m sure that will sound familiar.