There's an old mariner's saying: Cross the southern latitude lines that mark the Roaring 40s, the Furious 50s and the Screaming 60s and you reach a place, down near the bottom of Earth – and not far from where the wreckage of a crashed Malaysia Airlines jetliner is believed to lie – where there is no god.
"When you get the big storms down there, it's horrendous. The seas scream. The winds are screeching. It's like being on the doorstep of hell," says Tony Bullimore, a British sailor and adventurer.
In 1997 he spent six days trapped there, in the southern reaches of the Indian Ocean, a place Malaysian authorities said Monday is the likely grave for the 239 people on board Flight MH370. The jet went missing March 8 en route from Kuala Lumpur to Beijing, but veered sharply off course, heading toward Antarctica before, authorities believe, its fuel tanks ran dry and it crashed.
Its likely final resting place is among the most difficult on Earth to stage a search mission for wreckage and, ultimately, the "black box" voice and data recorders that might be able to resolve the mystery of what went wrong. The waters there are remote, about 2,500 kilometres southwest of Australia. They are cold, with current temperatures of 12 C and winter approaching. They are deep, in places nearly four kilometres from surface to bottom. They are complex, with a mess of swirling currents so convoluted they can, in very short order, take adjacent objects – such as floating aircraft wreckage – and separate them by hundreds of kilometres.
And they are deeply hostile, as Mr. Bullimore discovered when his sailboat capsized midway through a race around the world. He spent days holding on for life inside an air pocket in the vessel's hull. He severed one of his own fingers to avoid drowning, after it became stuck while he was underwater trying to free the boat's life raft. He laid an elaborate plan for how he would die, floating strapped to the back of the boat. "Maybe someone would have spotted the boat three months later and seen a skeleton hanging on to the rudder," he says, speaking from his home in Bristol, U.K. "Quite honestly, I did not believe that rescue was coming. I thought I was about a day away from the end of my life."
But he was lucky. He had an emergency beacon that brought rescuers his way, spotting his overturned Exide Challenger in a place where winds can hit 200 kilometres per hour and swells can tower at 30 metres. Even on calm days, the swells are often three to four metres in height. But the calm days are few.
"There's normally a storm coming through four or five out of every seven days," said David Dicks, another round-the-world sailor who has been through the area. The waves alone are enough to complicate a search for aircraft debris. "There's lots of whitewater, lots of rolling cascading waves. It would be very hard to spot something, certainly from a vessel" – but also from an aircraft, where an object "would only have to be covered by a small patch of whitewater or cloud and you've missed it," said Mr. Dicks, who lives in Perth, Australia.
The area below 40 degrees of south latitude was named the "Roaring 40s" by mariners who, centuries ago, discovered it as a southern ocean superhighway to India. Here, winds were virtually guaranteed to move ships eastward from the southern tip of Africa. Nineteenth-century maps show a thick band of shipping in a straight line near the 40th parallel. (Modern-day ships, with no need for the wind, barely go there.)
"It's south of all the big land masses, so the winds – which are from the west – howl around the bottom of the earth there without any obstruction," said John Bach, who is among Australia's most-respected maritime historians. "That's what gives them time to build up vast waves."
Conditions are equally fearsome beneath the surface, where the area's currents defy easy description. They are a swirling mess of eddies; a map showing 30 years of buoy tracks is a thicket of spirals; it looks like the waters have been given a perm, albeit one that is constantly changing. Picture the circular movement of a hurricane, except in the water and at slower speed. Some of those are produced by the sheer speed of current movement, some seven kilometres per hour, much faster than in other ocean waters.
"Trying to predict where flow actually goes is really, really hard," said Erik van Sebille, a physical oceanographer at the University of New South Wales. In December, researchers working in southern waters released pairs of buoys 10 metres apart and used satellites to track their movement.
A few days later, the currents and winds had split each pair by several kilometres. Within three months, some were thousands of kilometres apart. Within a year, pieces of wreckage could end up in different oceans.
That means it is likely to be difficult to trace back the movement of floating aircraft debris, a necessary step to finding where sunken wreckage – likely including the black box – may be found. (In the case of Air France Flight 447, where wreckage was spotted less than two days after the crash, it took nearly two years to find the flight recorders.)
"It's hard to say, but my intuition would say it's going to be virtually impossible to backtrack this to within a 100-kilometre range," Mr. van Sebille said.