food chains mosquito eggs and larvae form big links. Others will be flowers: when mosquitoes aren’t sucking blood, they sip nectar—the main meal for all male mosquitoes, although vampirish females drink it as well. That makes them pollinators, so the world without us will bloom anew.
The other gift to mosquitoes will be restoration of their traditional homelands—in this case, home waters. In the United States alone, since its founding in 1776, the part of their prime breeding habitat, wetlands, that they have lost equals twice the area of California. Put that much land back into swamps, and you get the idea. (Mosquito population growth would have to be adjusted for corresponding increases in mosquito-eating fish, toads, and frogs—though, with the last two, humans may have given the insects yet another break: It’s unclear how many amphibians will survive chytrid, an escaped fungus spread by the international trade in laboratory frogs. Triggered by rising temperatures, it has annihilated hundreds of species worldwide.)
Habitat or not, as anyone knows who lives atop a former marsh that was drained and developed, be it in suburban Connecticut or a Nairobi slum, mosquitoes always find a way. Even a dew-filled plastic bottle cap can incubate a few of their eggs. Until asphalt and pavement decompose for good and wetlands rise up to reclaim their former surface rights, mosquitoes will make do with puddles and backed-up sewers. And they can also rest assured that one of their favorite man-made nurseries will be intact for, at minimum, another century, and will continue making cameo appearances for many more centuries thereafter: scrapped rubber automobile tires.
Rubber is a kind of polymer called an elastomer. The ones that occur in nature, such as the milky latex extract of the Amazonian Para tree, are, logically, biodegradable. The tendency of natural latex to turn gooey in high temperatures, and to stiffen or even shatter in cold, limited its practicality until 1839, when a Massachusetts hardware salesman tried mixing it with sulfur. When he accidentally dropped some on a stove and it didn’t melt, Charles Goodyear realized that he’d created something that nature had never tried before.
To this day, nature hasn’t come up with a microbe that eats it, either. Goodyear’s process, called vulcanization, ties long rubber polymer chains together with short strands of sulfur atoms, actually transforming them into a single giant molecule. Once rubber is vulcanized—meaning it’s heated, spiked with sulfur, and poured into a mold, such as one shaped like a truck tire—the resulting huge molecule takes that form and never relinquishes it.
Being a single molecule, a tire can’t be melted down and turned into something else. Unless physically shredded or worn down by 60,000 miles of friction, both entailing significant energy, it remains round. Tires drive landfill operators crazy, because when buried, they encircle a doughnut-shaped air bubble that wants to rise. Most garbage dumps no longer accept them, but for hundreds of years into the future, old tires will inexorably work their way to the surface of forgotten landfills, fill with rainwater, and begin breeding mosquitoes again.
In the United States, an average of one tire per citizen is discarded annually—that’s a third of a billion, just in one year. Then there’s the rest of the world. With about 700 million cars currently operating and far more than that already junked, the number of used tires we’ll leave behind will be less than a trillion, but certainly many, many billions. How long they’ll lie around depends on how much direct sunlight falls on them. Until a microbe evolves that likes its hydrocarbons seasoned with sulfur, only the caustic oxidation of ground-level ozone, the pollutant that stings your sinuses, or the cosmic power of ultraviolet rays that penetrate a damaged stratospheric ozone layer, can break vulcanized sulfur bonds. Automobile tires therefore are impregnated with UV inhibitors and “anti- ozonants,” along with other additives like the carbon black filler that gives tires their strength and color.
With all that carbon in tires, they can be also burned, releasing considerable energy, which makes them hard to extinguish, along with surprising amounts of oily soot that contains some noxious components we invented in a hurry during World War II. After Japan invaded Southeast Asia, it controlled nearly the entire world’s rubber supply. Understanding that their own war machines wouldn’t go far using leather gaskets or wooden wheels, both Germany and the United States drafted their top industries to find a substitute.
The largest plant in the world today that produces synthetic rubber is in Texas. It belongs to the Goodyear Tire & Rubber Company and was built in 1942, not long after scientists figured out how to make it. Instead of living tropical trees, they used dead marine plants: phytoplankton that died 300 million to 350 million years ago and sank to the sea bottom. Eventually—so the theory goes; the process is poorly understood and sometimes challenged—the phytoplankton were covered with so many sediments and squeezed so hard they metamorphosed into a viscous liquid. From that crude oil, scientists already knew how to refine several useful hydrocarbons. Two of these—styrene, the stuff of Styrofoam, and butadiene, an explosive and highly carcinogenic liquid hydrocarbon— provided the combination to synthesize rubber.
Six decades later, it’s what Goodyear Rubber still makes here, with the same equipment rolling out the base for everything from NASCAR racing tires to chewing gum. Large as the plant is, however, it’s swamped by what surrounds it: one of the most monumental constructs that human beings have imposed on the planet’s surface. The industrial megaplex that begins on the east side of Houston and continues uninterrupted to the Gulf of Mexico, 50 miles away, is the largest concentration of petroleum refineries, petrochemical companies, and storage structures on Earth.
It contains, for example, the tank farm behind razor-edged concertina wire just across the highway from Goodyear—a cluster of cylindrical crude-oil receptacles each a football field’s length in diameter, so wide they appear squat. The omnipresent pipelines that link them run to all compass points, as well as up and down—white, blue, yellow, and green pipelines, the big ones nearly four feet across. At plants like Goodyear, pipelines form archways high enough for trucks to pass under.
Those are just the visible pipes. A satellite-mounted CT scanner flying over Houston would reveal a vast, tangled, carbon-steel circulatory system about three feet below the surface. As in every city and town in the developed world, thin capillaries run down the center of every street, branching off to every house. These are gas lines, comprising so much steel that it’s a wonder that compass needles don’t simply point toward the ground. In Houston, however, gas lines are mere accents, little flourishes. Refinery pipelines wrap around the city as tightly as a woven basket. They move material called light fractions, distilled or catalytically cracked off crude oil, to hundreds of Houston chemical plants—such as Texas Petrochemical, which provides its neighbor Goodyear with butadiene and also concocts a related substance that makes plastic wrap cling. It also produces butane—the feedstock for polyethylene and polypropylene nurdle pellets.
Hundreds of other pipes full of freshly refined gasoline, home heating oil, diesel, and jet fuel hook into the grand patriarch of conduits—the 5,519-mile, 30-inch Colonial Pipeline, whose main trunk starts in the Houston suburb of Pasadena. It picks up more product in Louisiana, Mississippi, and Alabama, then climbs the eastern seaboard, sometimes above-ground, sometimes below. The Colonial is typically filled with a lineup of various grades of fuel that pump through it at about four miles per hour until they’re disgorged at a Linden, New Jersey, terminal just below New York Harbor—about a 20-day trip, barring shutdowns or hurricanes.
Imagine future archaeologists clanging their way through all those pipes. What will they make of the thick old steel boilers and multiple stacks behind Texas Petrochemical? (Although, if humans stick around for a few more years, all that old stock, overbuilt back when there were no computers to pinpoint tolerances, will have been dismantled and sold to China, which is buying up scrap iron in America for purposes that some World War II historians question with alarm.)
If those archaeologists were to follow the pipes several hundred feet down, they would encounter an artifact destined to be among the longest-lasting ever made by humans. Beneath the Texas Gulf coast are about 500 salt domes formed when buoyant salts from saline beds five miles down rise through sedimentary layers. Several lie right under Houston. Bullet-shaped, they can be more than a mile across. By drilling into a salt dome and then pumping in water, it is possible to dissolve its interior and use it for storage.
Some salt dome storage caverns below the city are 600 feet across and more than half a mile tall, equaling a volume twice that of the Houston Astrodome. Because salt crystal walls are considered impermeable, they are used for storing gases, including some of the most explosive, such as ethylene. Piped directly to an underground salt dome formation, ethylene is stored under 1,500 pounds of pressure until it’s ready to be turned into plastic. Because it is so volatile, ethylene can decompose rapidly and blow a pipe right out of the ground. Presumably, it would be best for archaeologists of the future to leave the salt caverns be, lest an ancient relic from a long-dead civilization blow up in their faces. But how would they know?
Back above ground, like robotic versions of the mosques and minarets that grace the shores of Istanbul’s Bosphorus, Houston’s petroscape of domed white tanks and silver fractionating towers spreads along the banks of
