We’ve barely explored the darkest realm of the ocean. With rare-metal mining on the rise, we’re already destroying it.
The International Seabed Authority is headquartered in Kingston, Jamaica, in a building that looks a bit like a prison and a bit like a Holiday Inn. The I.S.A., which has been described as “chronically overlooked” and is so obscure that even many Jamaicans don’t know it exists, has jurisdiction over roughly half the globe.
Under international law, countries control the waters within two hundred miles of their shores. Beyond that, the oceans and all they contain are considered “the common heritage of mankind.” This realm, which encompasses nearly a hundred million square miles of seafloor, is referred to in I.S.A.-speak simply as the Area.
Scattered across the Area are great riches. Mostly, these take the shape of lumps that resemble blackened potatoes. The lumps, known formally as polymetallic nodules, consist of layers of ore that have built up around bits of marine debris, such as ancient shark teeth. The process by which the metals accumulate is not entirely understood; however, it’s thought to be exceedingly slow. A single spud-size nugget might take some three million years to form. It has been estimated that, collectively, the nodules on the bottom of the ocean contain six times as much cobalt, three times as much nickel, and four times as much of the rare-earth metal yttrium as there is on land. They contain six thousand times as much tellurium, a metal that’s even rarer than the rare earths.
The first attempts to harvest this submerged wealth were undertaken nearly fifty years ago. In the summer of 1974, a drillship purportedly belonging to Howard Hughes—the Hughes Glomar Explorer—anchored north of Midway Atoll, ostensibly to bring up nodules from the depths. In fact, the ship was operated by the C.I.A., which was trying to raise a sunken Soviet submarine. But then, in a curious twist, a real company called Ocean Minerals leased the Glomar to collect nodules from the seabed west of Baja California. The president of the company likened the exercise to “standing on the top of the Empire State Building, trying to pick up small stones on the sidewalk using a long straw, at night.”
After the Glomar expeditions, interest in seabed mining waned. It’s now waxing again. As one recent report put it, “The Pacific Ocean is the scene of a new wild west.” Thirty companies have received permits from the I.S.A. to explore the Area. Most are looking to slurp up the nodules; others are hoping to excavate stretches of the ocean floor that are rich in cobalt and copper. Permits to begin commercial mining could be issued within a few years.
Proponents of deep-sea mining argue that the sooner it starts the better. Manufacturing wind turbines, electric vehicles, solar panels, and batteries for energy storage requires resources, often scarce ones. (Tellurium is a key component in thin-film solar panels.) “The reality is that the clean-energy transition is not possible without taking billions of tons of metal from the planet,” Gerard Barron, the chairman of the Metals Company, one of the businesses that holds permits from the I.S.A., observed a few months ago. Seafloor nodules, he said, “offer a way to dramatically reduce” the environmental impact of extracting these tons.
But seabed mining poses environmental hazards of its own. The more scientists learn about the depths, the more extraordinary the discoveries. The ocean floor is populated by creatures that thrive under conditions that seem impossibly extreme. There is, for example, a ghostly pale deep-sea octopus that lays its eggs only on the stalks of nodule-dwelling sponges. Remove the nodules in order to melt them down and it will, presumably, take millions of years for new ones to form.
Edith Widder is a marine biologist, a MacArthur Fellow, and the author of “Below the Edge of Darkness: A Memoir of Exploring Light and Life in the Deep Sea” (Random House). Widder is an expert on bioluminescence, a topic that she became interested in after nearly going blind. In 1970, when she was a freshman in college, she had to have surgery for a broken back. The surgery went fine, but afterward she started hemorrhaging. Her heart stopped beating, and she was resuscitated. This happened again, and then a third time. Blood leaked into both of her eyes, blocking her retinas. “My visual world was swirling darkness with occasional glimpses of meaningless light,” she recalls. Eventually, she regained her vision, but she no longer took sight for granted.
“We believe we see the world as it is,” she writes. “We don’t. We see the world as we need to see it to make our existence possible.”
The same goes for fish. Only the top layers of the oceans are illuminated. The “sunlight zone” extends down about seven hundred feet, the “twilight zone” down another twenty-six hundred feet. Below that—in the “midnight zone,” the “abyssal zone,” and the “hadal zone”—there’s only blackness, and the light created by life itself. In this vast darkness, so many species have mastered the art of bioluminescence that Widder estimates they constitute a “majority of the creatures on the planet.” The first time she descended into the deep in an armored diving suit called a wasp, she was overwhelmed by the display. “This was a light extravaganza unlike anything I could have imagined,” she writes. “Afterwards, when asked to describe what I had seen, I blurted, ‘It’s like the Fourth of July down there!’ ”
Bioluminescent creatures produce light via chemical reaction. They synthesize luciferins, compounds that, in the presence of certain enzymes, known as luciferases, oxidize and give off photons. The trick is useful enough that bioluminescence has evolved independently some fifty times. Eyes, too, have evolved independently about fifty times, in creatures as diverse as flies, flatworms, and frogs. But, Widder points out, “there is one remarkable distinction.” All animals’ eyes employ the same basic strategy to convert light to sensation, using proteins called opsins. In the case of bioluminescence, different groups of organisms produce very different luciferins, meaning that each has invented its own way to shine.
The most obvious reason to flash a light in the dark is to find food. Some animals, like the stoplight loosejaw, a fish with photon-emitting organs under each eye, use bioluminescence to seek out prey. Others, like the humpback blackdevil, hope to attract victims with their displays; the blackdevil sports a shiny lure that dangles off its forehead like a crystal from a chandelier.
Bioluminescence also serves less straightforward functions. It can be used to entice mates and to startle enemies. The giant red mysid, a hamster-size crustacean, spews streams of blue sparkles from nozzles near its mouth; these, it’s believed, distract would-be attackers. Some animals smear their pursuers with bioluminescent slime—the marks make them targets for other predators—and some use bioluminescence as camouflage. This last strategy is known as counterillumination, and it’s used in the twilight zone, where many creatures have upward-looking eyes that scan for the silhouettes of prey. The prey can adjust their glow to blend in with the light filtering down from above.
Since it’s so hard for humans to get to the deep sea—and, once there, to record what they’re seeing—Widder has spent much of her career trying to figure out ways to study bioluminescence remotely. She’s developed special deep-sea cameras that rely on red light, which marine creatures mostly can’t detect. Much of “Below the Edge of Darkness” is occupied with the travails of getting these cameras placed, a project that involves journeys so nauseating that Widder describes cycling through the five stages of seasickness. In the fourth, she explains, “you’re afraid you’re going to die,” and in the last “you’re afraid you’re not.”
The experience that she really wants to convey, though, is not queasiness but wonder. The creatures of the deep have been putting on the world’s greatest light show for tens of millions of years. Widder thinks that if people could witness this spectacle—or even just be made aware of it—they’d pay a lot more attention to life at the bottom of the seas and the many hazards that threaten it. These include but are not limited to global warming, ocean acidification, overfishing, agricultural runoff, oil spills, invasive species, bottom trawling, plastic waste, and seabed mining.
“We seem to be in a Catch-22 scenario where we haven’t explored the deep ocean because we don’t appreciate what a remarkable, mysterious, and wondrous place it is, and we don’t know what an astonishing place it is because we haven’t explored it,” she argues. Meanwhile, she writes, “we are managing to destroy the ocean before we even know what’s in it.”
All marine photosynthesis takes place in the sunlight zone. Beneath that, food is in such short supply that the occasional dead whale that falls to the ocean floor represents a major source of nutrients. Nevertheless, even in the farthest recesses of the oceans, life finds a way.
The Mariana snailfish, as its name suggests, occupies the Mariana Trench—the ocean’s deepest depression—in the western Pacific. It’s a few inches long and looks like a large, pale-pink tadpole. The Mariana snailfish has been found more than twenty-six thousand feet below sea level, where the pressure is eight hundred times greater than at the surface. To survive under such conditions, the snailfish has come up with various ingenious adaptations: its skull is not completely closed, its bones are unusually rubbery, and it produces special chemicals to prevent its proteins from denaturing under stress. The creature can barely see and instead relies on fluid-filled chambers along its jaws, which detect the movements of small crustaceans known as amphipods. Amphipods, for their part, have been collected from the very bottom of the Mariana Trench, almost thirty-six thousand feet down, where the pressure is so great that the animals’ shells, in theory at least, should dissolve. A team of Japanese scientists recently reported that one deep-dwelling amphipod, Hirondellea gigas, protects its shell by coating it in an aluminum-based gel, produced from metal that it extracts from seafloor mud.
Some of the seas’ most extraordinary animals live around hydrothermal vents—the oceanic equivalents of hot springs. Through cracks in the seafloor, water comes in contact with the earth’s magma; the process leaves it superheated and loaded with dissolved minerals. (At some vents, the water reaches a temperature of more than seven hundred degrees.) As the water rises and cools, the minerals precipitate out to form crenellated, castlelike structures. Hydrothermal vents had been theorized about for many years but remained unseen until 1977, when a team of geologists and geochemists travelling on a research vessel called the Knorr located one about two hundred and fifty miles northeast of the Galápagos. A pair of scientists went down to take a look at it in a submersible named Alvin.
“Isn’t the deep ocean supposed to be like a desert?” one of them asked over Alvin’s phone link.
“Yes,” came the answer from the Knorr.
“Well, there’s all these animals down here.”
As Helen Scales, a British marine biologist, explains in her new book, “The Brilliant Abyss: Exploring the Majestic Hidden Life of the Deep Ocean, and the Looming Threat That Imperils It” (Grove Atlantic), “these animals” turned out to be fundamentally different from other creatures. At the bottom of the vents’ food chains are microbes that have come up with their own novel survival strategy. Instead of using photosynthesis, which harnesses the energy of photons, they rely on chemosynthesis, which uses the energy stored in chemical bonds. Since the late nineteen-seventies, Scales reports, researchers have catalogued hundreds of strange species living around vents; they include creatures so puzzling that it’s hard to find a limb for them on the tree of life.
Yeti crabs, first observed in 2005 on a vent system along the Pacific-Antarctic Ridge, south of Easter Island, look like hairy white lobsters. Their “hairs” are actually extensions of their shells, and along them live colonies of chemosynthetic bacteria, which the crabs scrape up and consume. Yeti crabs were found to be so evolutionarily distinctive that taxonomists had to create not just a new genus but a whole new family for them.
Xenoturbella profunda is a creature that looks like a discarded tube sock. First collected from a vent system in the Gulf of California in 2015, it has no intestines or central nervous system, and scientists aren’t even sure what phylum it belongs to. Chrysomallon squamiferum, commonly referred to as the scaly-foot snail, is a mollusk that’s been found at vents in the Indian Ocean, at a depth of ten thousand feet. It’s the only animal known to build its shell with iron, and around its foot it sports a fringe of iron plates that looks a bit like a flamenco skirt. The snail carries around chemosynthesizing microbes in a special pouch in its throat. In 2019, Chrysomallon squamiferum became the first vent-dwelling creature to be included on the Red List of Threatened Species, maintained by the International Union for Conservation of Nature. The rationale for the listing is that the species has been found at only three sites, and two of these are being explored for mining. Its living space, the I.U.C.N. has observed, is thus apt to be “severely reduced or destroyed.”
Scales, like Widder, worries that the bottom of the ocean will be wrecked before many of the most marvellous creatures living there are even identified. “The frontier story has always been one of destruction and loss,” she writes. “It is naïve to assume that the process would play out any differently in the deep.” Indeed, she argues, the depths are particularly ill-suited to disturbance because, owing to a scarcity of food, creatures tend to grow and reproduce extremely slowly. “Vital habitat is created by corals and sponges that live for millennia,” she writes.
If deep-sea mining proceeds, it’s likely that one of the first countries to pursue it will be Nauru, a tiny nation that, as it happens, was itself almost destroyed by mining.
About the size of Block Island, Nauru sits in the South Pacific, about sixteen hundred miles northeast of Papua New Guinea. For thousands of years, the island’s largest visitors were birds, which used it, in the words of one journalist, as a “glorified rest stop.” Polynesians and Micronesians arrived on the island sometime around 1000 B.C. They seem to have lived harmoniously—even idyllically—until gun-toting Europeans showed up, in the early nineteenth century. At the start of the twentieth century, a New Zealander named Albert Ellis realized that the ancient bird droppings that coated the island were a rich source of phosphate, an important fertilizer. During the next six decades, more than thirty-five million tons of phosphate were dug out of Nauru and shipped off to farms in Europe and Australia. The process stripped much of the island bare, leaving nothing but jagged pillars of limestone sticking out of the ground. A National Geographic photographer who visited Nauru mid-destruction wrote, “A worked-out phosphate field is a dismal, ghastly tract.”
In 1968, Nauru became its own country. The phosphate business was still booming, and, on paper, the island’s ten thousand residents became some of the richest people in the world. The new nation used its sovereign wealth to invest in, among other things, cruise ships, airplanes, overseas office buildings, and a London musical based on the life of Leonardo da Vinci. The musical flopped, as did most of the other ventures. Nauruans “have a long history of being taken to the cleaners by crooks” is how Helen Hughes, an Australian economist, put it. In 2001, in return for various fees and payments, Nauru’s government allowed Australia to set up a detention center for refugees on the island. The center soon became infamous for its grim conditions.
Today, with the phosphate mostly mined out and the refugees mostly resettled, Nauru is betting on nodules. To engage in deep-sea exploration and mining, a company must be sponsored by a country that’s party to the United Nations Convention on the Law of the Sea. (The U.S. is one of the few nations that has not ratified the Law of the Sea treaty, because of conservative opposition in the Senate.) Nauru has teamed up with the Metals Company, which is based in Canada, to explore a region of the Pacific known as the Clarion-Clipperton Zone, west of Mexico. “We are proud that Pacific nations have been leaders in the deep-sea minerals industry,” a statement co-authored by Nauru’s representative to the International Seabed Authority recently declared. The deal, it’s estimated, could eventually bring the country more than a hundred million dollars a year. Alternatively, the arrangement could prove even more disastrous than the da Vinci musical. At one point, Nauru officials expressed concern to the I.S.A. that, if a sponsoring nation were held liable for damages arising from a mining operation, it could “face losing more than it actually has.”
The I.S.A., for its part, has been assigned the task not just of issuing the permits for seabed mining but also of drafting the regulations to govern the practice. These regulations have yet to be finalized, so it’s unclear how stringent they will be. (The final rules are supposed to be in place before commercial mining commences, though the Metals Company has threatened to try to start without them.) Many marine scientists argue that because deep-sea ecosystems are so fragile—and operations that are miles below the surface so difficult to monitor—the only safe way to proceed is not to. Scales makes this point, but acknowledges that the I.S.A. is unlikely to be swayed. She quotes Daniel Jones, a researcher at the British National Oceanography Centre, who says, “Even if we found unicorns living on the seafloor, I don’t think that would necessarily stop mining.” Meanwhile, assuming that mining does go forward, it’s been suggested that faux nodules could be manufactured and dropped by ship into the deep ocean, to replace those being refashioned into batteries. The perfect vessel for this task would have been the Glomar; unfortunately, a few years ago it was sold for scrap.
Elizabeth Kolbert, a staff writer at The New Yorker since 1999, won the 2015 Pulitzer Prize for “The Sixth Extinction.” Her latest book is “Under a White Sky: The Nature of the Future.”
(Sources: The New Yorker)
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