Moby-Duck (45 page)

At the other extreme from the megascale gyres are “microscale eddies,” eddies the size of dance floors or dimes, and if you would like to see one, drag your hand through a bathtub and watch. There they go, swirling away, as ephemeral as they are small. Throw a rubber duck in and you can watch it swirl away too. If you were a god dragging your divine hand through the ocean basins, that's what mesoscale eddies would be like. Underwater storms are slower than atmospheric ones. The watery winds of an Irminger Ring attain a “swirl speed,” Bower said, of around one mile per hour—the speed, in other words, not of a hurricane or a gale but of a breeze.

Their slowness belies their strength. In their watery coils they can transport up to 1.95 trillion cubic meters of water, along with flora and fauna and flotsam, seaweed and krill, driftwood and rubber ducks. They can also, if warmer than the water through which they swirl, as Irminger Rings are, transport heat, how much no one precisely knows. A few years ago, a Seaglider—a kind of motorized remote-controlled underwater drone—strayed into a gathering Irminger Ring while exploring the Irminger Current, which winds westward around Greenland's continental shelf. Caught in an underwater storm, it took the motorized glider fourteen days to break free and resume its preprogrammed route.

Underwater storms are also smaller than atmospheric ones—Irminger Rings measure, on average, thirty miles across. They're also denser, of course, which explains their sluggishness, and their sluggishness in turn explains this: much as mammals with slow metabolisms tend to have long life spans, so the longevity of underwater storms tends to exceed that of their atmospheric counterparts. Hurricanes decay and vanish just days after meteorologists name them. A mesoscale eddy of water by contrast can last—or “live,” as Bower likes to say—for many months.

Perhaps the most meaningful difference between atmospheric storms and underwater ones from a terrestrial point of view is this: you can't see mesoscale eddies, or feel them. You could be sailing on calm seas, at Beaufort force o (“sea like a mirror”), and the underwater storm of the century could be swirling slowly beneath you. Nobody gives them names, or watches them on the Weather Channel. Nevertheless they are as much a cause and effect of the climate as rogue waves and hurricanes. What made the “relatively new discovery” of mesoscale eddies so exciting? Until recently, no one, not sailors or scientists, knew that the world below the waves was such a stormy place.

 

 

By sunset we are somewhere east of Boston, no land in sight. The skies have begun to clear. A crescent moon rises to starboard. Through a porthole in the main lab I watch the black shape of a cargo ship—a post-Panamax container ship, by the look of it—cross the sunset in silhouette. After a dinner of buttery fish and rice in the mess, the
Knorr
's off-duty oilers and deckhands gather in a lounge to watch a movie about an assassination plot. Long after the portholes have all gone black, through the lounge's closed door, the muffled sound of gunfire can be heard. On the bridge one officer and one able-bodied seaman stand watch in darkness, their faces, lit by screens, like those of sleepy revenants. In the main lab, Bower stays up late working at her computer, which blows documents up to a scale she can decipher. Special software speed-reads text aloud in a robotic voice as nonsensical to my ears as the chattering of a telegraph. Taking a break from her work, she clicks through the library of music she's brought along. “I always loved this song,” she announces, and a moment later, somewhere out on the Gulf of Maine, inside the
Knorr
's main lab, UB40's “Red Red Wine” begins to play.

In my windowless cabin belowdecks, I stay up late reading about the history of oceanography. When I turn out my bunkside light, the darkness is absolute, as black a darkness as I've experienced, and I wonder if this is what it's like to be totally blind. I have been, since the age of four or five, acutely myopic. I spent my childhood wearing—and losing, and replacing, and lashing to my head with unflattering elastic accoutrements—spectacles with Coke-bottle lenses and breakproof plastic frames made, unconvincingly, to resemble tortoiseshell. From such eyewear I was liberated, as a teenager, by the contact lens, to the inventors of which I will remain eternally grateful, whatever my misgivings about disposable plastics. Without glasses or contact lenses I too would be prohibited from driving. Without glasses or contacts, I should probably be prohibited from walking. I tried it once on the sidewalks of New York, circumambulating by night while visually impaired. Traffic lights turned into colorful chandeliers, pedestrians into shadows that caught me by surprise. To read a book without contact lenses or glasses, I have to bury my face between the pages so that I appear to be snorting meanings through my nostrils.

Aboard the
Knorr,
in the darkness of my submarine cabin, I lie awake awhile, eyes open, contacts out, glasses off, wondering what Beth and Bruno are doing, listening to the pulsing RPMs of the engines below and to the amniotic hiss and whoosh of the waves above. Then I close my eyes and fall asleep thinking how strange it is that I am below the surface of the high Atlantic. Inches from my pillow, for all I know, fish swim.

In 323 B.C., the last year of his life, charged with philosophical heresies by the pagan inquisitors of Athens, Aristotle—generally regarded by scientific historians as the forefather of oceanography—fled to his family's country house in Chalcis on the Greek island of Euboea. Chalcis happens to be one of the best spots in the Mediterranean to observe the tides, a phenomenon of which the Greeks of Aristotle's time were largely unaware, for good reason. Tides in the shallow, enclosed waters of the Mediterranean are weak, so weak that on some shores near Athens, the difference between flood and ebb measures less than a centimeter. If you were an ancient Athenian, you too would be unaware of the tides. Unless, that is, you'd visited a place like Chalcis.

There the Euripus Strait, separating the island of Euboea from the Greek mainland, narrows into a channel only 130 feet wide. There even the weak tides of the Mediterranean make the funneled water diurnally rush, frothing and churning, first in one direction, then the other. This twice-daily riot was something undreamt of in Aristotle's philosophy. In fact, Aristotle believed that since water seeks its level and in the ocean finds it, below its windy surface the ocean must be still, as if an ocean basin were a kind of giant cistern. A few months after retiring to Chalcis, the forefather of oceanography died. The cause of death?

According to a legend that persisted into the seventeenth century: drowning. Suicidal drowning. Suicidal drowning brought on by despair. Despair brought on by confusion. Confusion induced by the sea. Confronted with the tumultuous, inexplicable waters of the Euripus Strait, Aristotle supposedly hurled himself into them. “The great Master of Philosophy drowned himself,” the seventeenth-century British scientist Richard Bolland wrote, “because he could not apprehend the Cause of Tydes.” So begins the history of physical oceanography. Except that it's mostly fictional. Aristotle did indeed flee to Chalcis, but the actual cause of his death was an undiagnosed gastrointestinal ailment, brought on, probably, by a funky oyster. In Aristotle's suicidal confusion, it seems, Bolland and his seventeenth-century oceanographic colleagues saw their own.

Just twelve years after Bolland repeated the apocryphal story of Aristotle's suicide, Isaac Newton finally determined the lunar and solar “Cause of Tydes.” The currents, however, would prove to be an even more maddeningly intractable riddle. “The secrets of the currents in the seas,” Melville observes in
Moby-Dick,
which unlike most novels includes citations to actual scientific papers, “have never yet been divulged, even to the most erudite research.” By the time Melville died, in 1891, most of the major surface currents had been charted, or at least sketched, but they had yet to be explained. “We are now becoming acquainted with only the roughest features of the oceanic circulations,” the oceanographer Harald Sverdrup observed in a 1929 article called “The Mystery of Ocean Currents.” Three years later the British mathematician Horace Lamb famously remarked, “I am an old man now, and when I die and go to Heaven there are two matters on which I hope for enlightenment. One is quantum electrodynamics, and the other is the turbulent motion of fluids. And about the former I am really rather optimistic.”

By the 1950s, oceanographers, many of them at Woods Hole, seemed finally on the verge of solving the mystery of ocean currents and had even begun to illuminate what the “scientifics” of the
Challenger
expedition had called “the dismal abyss.” What the space race would later do for astronomy, the submarine warfare of World War II did for ocean science. Deep-sea explorers were the astronauts of the postwar years, the abyss the final frontier. No longer a howling waste, or a great blankness, the ocean had become the latest locus of an old, elusive dream: the dream of a new world. “In this Kingdom most of the plants are animals, the fish are friends, colors are unearthly in their shift and delicacy,” the deep-sea explorer William Beebe had written in the 1930s. “Here miracles become marvels, and marvels recurring wonders.” Now, in the 1950s, with the advent of underwater cinematography, we could all be armchair deep-sea explorers of this magical kingdom. Jacques Cousteau was a celebrity and Rachel Carson's
The Sea Around Us
a bestseller. A former director of WHOI appeared on the cover of
Time
. In his first State of the Union address, Kennedy declared, in a passage that would now seem anachronistic, “We have neglected oceanography, saline water conversion, and the basic research that lies at the root of progress.” With instruments developed for the U.S. Navy, aboard research vessels the Pentagon had subsidized, marine geographers mapped the seafloor in exquisite detail, supporting the then controversial theory of plate tectonics. Currents flowed through the earth's mantle, their soundings revealed, as well as through water and air. Everything was adrift, even continents. The only difference was the rate of flow.

In the last chapter of
The Sea Around Us,
published in 1950, Rachel Carson informed her readers that the benighted cartographers of the Middle Ages had thought of the ocean as the “dread Sea of Darkness.” Over the centuries, little by little, explorers and then scientists had pulled the veil of darkness back. “Here and there, in a few out-of-the-way places, the darkness of antiquity still lingers over the surface of the waters,” Carson wrote. “But it is rapidly being dispelled, and most of the length and breadth of the ocean is known; it is only in thinking of its third dimension that we can still apply the concept of the Sea of Darkness. It took centuries to chart the surface of the sea; our progress in delineating the unseen world beneath it seems by comparison phenomenally rapid.”

If Carson had stopped there, if she'd made of oceanography yet another chapter in the triumphant march of progress, implying that soon there would be no watery mysteries left, the ocean would have made of her a fool, as it had of Aristotle. But Carson didn't end her story on a triumphant note. Prophetically, she added this: “Even with all our modern instruments for probing and sampling the deep ocean, no one now can say that we shall ever resolve the last, the ultimate mysteries of the sea.” Which brings us to mesoscale eddies.

 

 

In 1960, aboard a one-hundred-foot ketch called the
Aries,
a British oceanographer named John Swallow sailed northeast out of Bermuda into the Sargasso Sea in search of a vast, deep, and altogether hypothetical northerly current that he was confident he would find. He was confident because a scientist at Woods Hole, Henry Stommel, the Isaac Newton of physical oceanographers, had deduced its existence. Most oceanographers sailed out, collected data, and then interpreted it. Stommel made his most important discoveries on land, with pencil and paper. In 1947, scribbling on a place mat at a roadside diner, he'd mathematically explained the physics of the Gulf Stream. And in the midfifties, once again with pencil and paper, for sound mathematical reasons, he'd hypothesized that beneath the northerly Gulf Stream there must be another fast-moving western boundary current—the Gulf Stream's shadowy twin, its abyssal, invisible doppelgänger—flowing in the opposite direction, south, toward the equator.

How to prove this hypothesis? On the far side of the Atlantic, John Swallow had found a way. To follow a deep current, Swallow realized, what you needed was a neutrally buoyant float, ballasted to sink toward but not quite to the ocean floor. If you equipped such a float with a battery-powered transducer that could send forth pings, oceanographers aboard a research vessel could track it—not with terrestrial eyes, but with aquified ears. In March 1957, west of Bermuda, aboard the British research vessel
Discovery II
, Swallow had launched three of his experimental floats—Swallow floats, they're now called—into rough seas. One collided, ruinously, with the
Discovery II
. One wandered aimlessly about. The third Swallow failed to track. Launching eight more floats, Swallow's experiment met with success: one was lost, but seven were carried south, below the Gulf Stream, by the unseen current whose existence Henry Stommel had divined.

Now, three years later, in 1960, aboard the
Aries
, Swallow expected to vindicate Stommel once again. Again he cast his floats overboard. Then, from the deck of the ketch, he lowered his hydrophone into the water and listened for pings. This time his floats sauntered extravagantly, first one way, then another. They spun. They described arcs. They meandered. They doubled back. Not one of them drifted steadily north, as Stommel had predicted. Even more than those of the castaway toys, their drift routes seemed hand-drawn by a cartographer with palsy, a drunken cartographer with palsy. Examining his chaotic data, Swallow began to discern a vortical method to this oceanic madness. His floats hadn't charted rivers in the sea. Instead they'd revealed watery breezes, watery winds, watery storms, and this revelation fundamentally changed the way scientists think of the sea.