I chose an apartment in Arabi because it was remote and visited by Mississippi River mists and near a hulking old sugar plant that billowed singed vapors into the tropical bayou night. Some would call the neighborhood, just five miles east of downtown New Orleans, a wasteland, but to me, at the time, it seemed gritty and magical, an exciting place to move with a woman whom I had just met. Her name was Karret, and a few weeks later we rented a minivan and piled in the few belongings we hadn’t sold at stoop sales, along with her rescue cats and dogs—my new family—and departed New York City. We drove through New Jersey and Pennsylvania under an azure sky, Karret watching it all from behind big red-lensed sunglasses that made the objects of the world look like they were burning. On a dark highway in Virginia, deep in the night, we came upon a horrible accident—cars and trucks piled in the cool summer blackness. Glowing silently at the edge of the woods were orange detour signs, and we followed their path down a country road, wide arcs that got narrower and narrower, turning in on themselves and in on themselves again, such that the detour was leading us into a spiral. Scenery collapsing, exhaustion mounting, cats asleep in their cages, dogs asleep in our laps, everything revolving in the darkness, back toward a single indefinable bright point in the center.
It didn’t hit me then, the importance of the spiral, but the mysteriousness of that moment has remained. Several miles beyond the accident, Karret and I somehow reemerged onto the highway and raced through the star-flecked night, curving south around the lip of the Appalachians and bending down into the cypress swamps, down into the bowl of New Orleans, where suddenly it was hot and August and the highway was lined with palm trees. The beat-up city serenaded us with its humidity and clanging noises. We picked up the keys to our apartment at a seedy French Quarter bar called the Three Legged Dog. Getting back in the van, we laughed nervously because we’d almost made it, and had no idea what that meant, or what it would mean and continue to mean, this sultry new home of ours, these strange new lives of ours.
Arabi was a nightmare. The water, which comes from the Mississippi River, was poison, spiked with trihalomethanes and haloacetic acids. These compounds, according to a letter we later received from the parish, could lead to “liver or kidney problems, or nervous system effects,” and cancer. The water contained weird life, too. We put jars of it on the windowsill and days later watched worm-like creatures take shape and squiggle about. Indeed, several months after we moved in, a four-year-old boy died when amoebas, discovered in the tap water, ate into his brain. The air, infused with sulfur dioxide from the oil refineries, was also poisonous; just three miles from our apartment was an ExxonMobil refinery whose smokestack emissions floated down our street, wrapping around trees and homes, sneaking into our nostrils as we walked the dogs, scraping our eyes and throats. “Like ingesting a chemical perfume,” said Karret, “a little bit cloying, a little sweet, but burning.”
One morning I awoke to find our blue Honda speckled black: It had rained oil in the night. When I pulled into a nearby car wash, the line was already long—people knew what to do. This was, apparently, typical. Then Barbara, the beloved barkeep at Snoopy’s, a windowless watering hole down the street, had an aneurism. Drinking at the bar, we heard more stories: Apparently aneurisms were common, too.
I began to see the larger spiral of it all. New Orleans is an oil city, and the US an oil nation. Out in the marshes, and deeper out in the Gulf of Mexico, the Light Louisiana Sweet gushed blackish red from wells driven through a mile of seawater and more than two miles of salt deposits and rock. And while in New Orleans the Gulf’s buried fuel is invisible, beyond the Garden District mansions, the cocktails and parades, out on the margins, to the west in places like St. Rose, or to the east in places like Arabi, you could observe it being processed. Karret and I have driven past the oil refineries at night. Ethereal lights line the pipes and stacks, hiding the soot and smoke. Refineries glow on the horizon like crystal cities.
In 1951, William Rubey, in his final address as president of the Geological Society of America, delivered a prophetic speech on the geologic history of seawater. “The intimate dependence of living organisms on the chemical and physical conditions of their environment,” said Rubey, “is so familiar—for example, an adequate supply of oxygen in the air we breathe—that we are inclined to take it all for granted.” Turning his attention to one particular chemical compound, carbon dioxide, Rubey discussed what would result from releasing more of it into the ocean and atmosphere. “The effects of these changes on living organisms would be drastic,” he stated. “If the supposed increase of carbon dioxide happened suddenly, it would probably mean wholesale extinction of many of the marine species of today.”
Rubey’s predictions were largely ignored by the popular press, but at least a few chemists were listening. In the late 1950s, a geochemist named Charles David Keeling placed an instrument for measuring carbon dioxide near the top of a mountain in Hawaii. Being at a high altitude and in the middle of the ocean made the spot well suited for accurately testing the makeup of the atmosphere. Keeling soon made two remarkable discoveries. The first was that the Earth acted as a gigantic lung, inhaling carbon dioxide in summer via the leaves of trees in the northern hemisphere, where the majority of the world’s land is located, and exhaling the gas each winter when the leaves fell to the ground and rotted. The other finding was that carbon dioxide levels in the atmosphere were rising steadily. The cause, Keeling eventually showed, was the burning of fossil fuels.
In 1978, Peter Brewer, an ocean chemist at Woods Hole Oceanographic Institution, in Massachusetts, published a paper demonstrating that the carbon dioxide increase Keeling was observing in the atmosphere had a corresponding increase in the oceans. “The signal,” Brewer wrote, “will be very much easier to observe in future years as atmospheric CO2 inputs increase.”
This signal is now referred to as “ocean acidification.” According to National Oceanic and Atmospheric Administration (NOAA) researcher Richard Feely, roughly a quarter of the approximately 2 trillion tons of carbon dioxide humankind has released into the atmosphere since the beginning of the Industrial Revolution has been absorbed by the oceans. This has lowered the oceans’ average pH level from 8.2 to 8.1. The drop is profound, since the pH scale is logarithmic, meaning minor increases represent major shifts—your blood’s pH typically hovers around 7.4; lower it to 7.15 and you may go into a coma. Some scientists estimate ocean pH will drop to 7.8 or 7.7 by the end of this century. If humans burn through all of the planet’s oil and gas deposits, it could drop to 7.5 or lower, a rapid change in ocean pH the likes of which has not occurred in 50 million years.
Scientists still don’t know exactly what this will mean for marine life, but so far the evidence is troubling. Oyster larvae may no longer be able to form shells—die-offs have already begun in the Pacific Northwest and could well spread to other parts of the country. Young scallop shells could develop deformities. In Alaska, several economically valuable fisheries could collapse, including red king crab, Tanner crab, and pink salmon. The inner-ear bones of juvenile squids, helpful in navigation, could dissolve. Clown fish could lose their sense of smell, disrupting their ability to locate their homes. Dogfish could lose their ability to track prey. Coral reefs could dissolve. And certain red and some green algae could lose the ability to calcify, threatening reproduction, and also Earth’s oxygen supplies.
Reading the research, one gets the sense that ours is a doomed but golden age for ocean science. Choose an organism, immerse it in water with a pH value expected in the decades to come, record the particular way said organism’s basic life functions fall apart, publish, then monitor how real-time conditions in the ocean catch up to the caustic ones produced in the laboratory.
If documenting destruction is indeed what marine science has come down to, there is one particular group of marine organisms that have become the unlikely poster child: pteropods. These tiny, winged mollusks range in size from poppy seed to blueberry. Many have shells—stunning, delicate, calcium-carbonate structures that often take the form of spirals. Pteropods are obscure, and the most detailed book I could find on their basic biology—Pelagic Snails: The Biology of Holoplanktonic Gastropod Mollusks—was written in 1989. In the past several years, however, pteropods have appeared in dozens of research articles, earned a Twitter hashtag, and inspired not just a Hello Kitty doll but two Pokémon characters, Phione and Manaphy. In 2014, the Sant Ocean Hall at the Smithsonian Institution’s National Museum of Natural History ran a popular exhibit featuring stylized-aluminum pteropod sculptures. “They are very curious little animals,” Gareth Lawson, a Woods Hole biological oceanographer and advisor for the Smithsonian exhibition, told me. “And they are the sentinels of ocean acidification.”
Eventually we left Arabi for an artsy neighborhood in New Orleans, out of range of the oil rain and chemical clouds, but the soil of our new neighborhood park was striped with lead and we were still drinking Mississippi River water. At night after bad days we browsed rentals in places like Woodstock, New York, and Asheville, North Carolina, thinking that the mountains might save us. But, of course, carbon dioxide is being pumped into the air there, too, and diffusing into oceans everywhere. Eventually, according to some researchers, 85 to 90 percent of the human-produced carbon dioxide in the atmosphere may be absorbed by the oceans.
On my birthday, Karret and I drove to the sea. At a gazebo in a park along a bayou that was once the main channel of the Mississippi River, we ate cake and carved our names into the wood. Back on the road headed south, dead oak trees appeared, murdered by salt, reaching out of the marsh and into an azure sky, a sky like the day we first left New York for Louisiana. And the road continued on, deeper into the sinking wetlands. Before reaching the Gulf I wanted to show Karret a certain place, a peek at the machinery that runs the world, pure sweat and machine, heliports and communication towers and control valves and loading docks and offshore support vessels and 1,200 trucks a day, delivering food and materials and men to be ferried out by the helicopters and vessels to the more than 4,000 oil-production rigs and drilling platforms located off the coast of Louisiana. From the beach we watched as, one by one, oil rigs lit up the horizon.
The truth is, scientists don’t exactly know how animals make shells. Somehow, special cells on or near the surface of shelled organisms draw two ingredients from seawater, a calcium ion and a carbonate ion, to make calcium carbonate. But as carbon dioxide is absorbed by the ocean it combines with water in a reaction that ends up reducing the number of available carbonate ions, which means less carbonate is available for making shells. When carbonate levels drop too low, not only are organisms such as pteropods unable to form new shell material, but the shells they have become riddled with pits and holes.
“We found severe levels of shell dissolution,” Nina Bednarek, an NOAA chemical oceanographer, reported in a 2012 Nature Geoscience paper that detailed an expedition to collect pteropods in the frigid stormy waters between Antarctica and the southern tip of South America. Cold water absorbs more carbon dioxide, and it accumulates over time at the bottom of the ocean. This makes cold oceans and areas of upwelling, where deep chilly nutrient-rich water is brought to the surface, good areas to look for effects of ocean acidification. Off the western coast of the United States, where upwelling occurs regularly every spring and summer, Bednarek found that a little more than half the pteropods sampled near the shore had shells severely damaged from dissolution. “These findings are important,” said Richard Feely, “because they show that not only are pteropod shells dissolving, they are dissolving even faster than scientific models have predicted.”
Pteropods don’t survive long in labs, making observations of their basic biology difficult. Some of the most detailed studies come from scientists in the 1970s and 1980s who dove down with scuba gear and observed pteropods in their own habitat. The animals often spend days at depths of a few hundred yards, to avoid being seen by predators, and migrate closer to the surface at night to feed. Much of the research then and since has focused on two species: Limacina helicina, what Bednarek examined in the Antarctic and off the western coast of the United States, and Clione limacina, which subsists almost exclusively on Limacina helicina. One night, at a local university library, I photocopied the relevant chapters out of that 1989 biology book to learn more about what it was we were possibly destroying.
Limacina helicina is about a quarter of an inch across and resembles a garden snail with a transparent shell and wings for feet, which allow it to fly through the sea. The creature eats by fishing with a net made of mucus that floats above it like a clear sticky balloon, trapping detritus, bacteria, small crustaceans, and even juvenile versions of its own kind. Clione limacina looks like a little demon with a jetpack—these are its wings. When chemoreceptors on Clione’s tentacles detect the presence of Limacina, nerve cells surrounding the esophagus trigger the animal to swim faster. Meanwhile, Limacina’s own chemoreceptors detect the danger, and the animal will abandon its mucus net and try to swim away. But Clione, with shorter wings and more efficient strokes, is faster. Six wormy tentacles spring from its head and adhere to Limacina. Clione inserts probes studded with small curved teeth called “hook sacs” deep inside Limacina’s shell and scrapes the meat out. For Limacina, this is the end.
At birth Limacina helicina is smaller than a grain of sand, and is sexually undeveloped. As the creature grows, it becomes a male, and the inner part of its shell fills with sperm. A penis and prostate develop. Sperm moves into a tube called the hermaphrodite duct, then into the seminal vesicle gland, which contributes fluid and discharges the sperm through a door called the “common genital pore.” From here, a path lined with tiny hairs called the “ciliated sperm groove”—like an elevated sperm highway—carries the sperm along the outside of the body and toward the penis, which ideally is well aligned with the common genital pore of the animal’s mate, which is also a male. The original pteropod’s gonads then transform in order to produce eggs, which are fertilized by its partner’s sperm.
We know that ocean acidification can riddle pteropod shells with holes, but what will happen to the organs hidden beneath, such as the sperm and gonads? And what triggers an individual to shift so quickly from male to female? When and how did pteropods first evolve, and what sort of ocean did they reside in? What capacity do pteropods have to withstand ocean acidification? Can they possibly detect and avoid increasedly acidic waters? And if pteropods go, what else goes with them? Some researchers have already pointed out that commercially important species such as Pacific salmon rely on pteropods for food. For the most part, though, the answers to these questions and many others remain unknown.
The transmission in the little blue Honda has died. These days, we walk, we take buses, we say, “Screw cars.” I’ve turned the Honda into an outdoor office, and on rainy days I sit in the broken vehicle and type on my laptop and watch the drops distort the view through the windshield down Desire Street.
“The city is fading, mouldering, crumbling—slowly but certainly,” Lafcadio Hearn wrote about New Orleans, in 1878. And it still is.
A few states east of Louisiana is a different sort of ocean. At the edge of a forest of dwarf live oak, saw palmetto, and slash pine, on a blazing night skeined with storms, Karret and I lie down on a white-sand beach, beaten down bits of quartz that were once the Appalachians, and observe the ocean in our periphery as we watch the sky above, ricocheted by lightning, erratic zippers of energy that illuminate us to each other in strange flashes. Lightning living out lives, lives that last seconds, seconds that when slowed down are really much more, are really worlds. It is the most exhilarating, incomprehensible thing, and by morning it will be gone. And soon enough, I imagine, we will be, too, retracing our route back north.