The Joplin, Missouri neighborhood where the author grew up.
The Joplin, Missouri neighborhood where the author grew up. Google Maps

The tornado that destroyed my hometown was born in an otherwise unremarkable atmospheric collision over the American Central Plains. On May 22, 2011, a geostationary satellite 22,300 miles overhead recorded a large collection of cloud lines drifting over southeastern Kansas. At around 2 p.m, one of the cloud lines exploded, like a cartographic-scale dry-ice bomb. Dense white vapors poured from nothing, and over the next five hours the National Oceanic and Atmospheric Administration monitored the growing supercell thunderstorm as it drifted toward a three-letter abbreviation on the map: “JLN.”

Just after 5 p.m., two storm chasers driving toward the western edge of Joplin, Missouri, spotted a translucent set of tendrils reaching down from the storm’s low black thunderhead. Almost as quickly as they formed, the tendrils disappeared. And then things took a turn. A dark blob half a mile wide congealed and dropped from the clouds. As it touched the ground, it filled with sparks from ruptured power lines, like a jar of fireflies. At 5:41, the National Weather Service office in Springfield, Missouri, issued this alert: NUMEROUS REPORTS OF TORNADO ON THE GROUND WEST OF JOPLIN AND POWER FLASHES.

“The tornado, as if it had been fueled by manmade structures and was now depleted, vanished.”The tornado intensified as it strafed the roofs and treetops of Joplin’s western suburbs. By the time it reached the city limits, where 49,000 people lived, it had evolved into an EF-5, the most destructive type of tornado on the Enhanced Fujita scale. Unlike EF-4s, which are merely “devastating,” EF-5s produce “incredible” damage. An EF-4 is powerful enough to scrape civilization off the planet in a matter of minutes. An EF-5 is more powerful still.

When the storm hit Joplin, the winds inside the funnel were spinning faster than 200 mph—yet the whole column was crawling forward at less than 10 mph, giving it time to wood-chip everything beneath it. The tornado produced a good deal of incredible, EF-5-worthy damage in the office park that surrounded St. John’s Hospital, one of the region’s major medical centers. In 45 seconds, it shifted the nine-story structure four inches off its foundation.

By then, the tornado was three quarters of a mile wide. As it tacked slightly to the north, it flattened a downtrodden swath of old Main Street. After gnawing through half a dozen intervening residential blocks, the tornado hit Joplin High School, a recently refurbished brick complex at the town’s middle-class core. Security cameras intended to monitor lunch-hour skippers now recorded surges of water that rendered the parking lot indistinguishable from a harbor in a hurricane. Inside, chairs and papers swarmed as the walls began to collapse.

neighborhood chart

May 23, 2011

The exact same neighborhood, pictured the day after the deadliest single tornado in modern history. Most of the damaged areas were unrecognizable even to lifelong residents.

The tornado churned on to the east, tagging its path with bizarre signatures—wood piercing asphalt, rubber piercing wood. It shaved away the neighborhood just east of the high school, including the little white one-story house where I spent my teenage years. It continued toward the main thoroughfare, Range Line Road, and destroyed a Home Depot, an Academy Sports & Outdoors, a Wal-Mart and a Pizza Hut, shotgunning shoppers with glass and metal and wood, burying some beneath cinder blocks, and needling others with blades of grass.

Meteorologists watching radar screens at a safe remove now saw a white-pink blob representing the tornado’s swirl of debris swing through the rest of the city like a wrecking ball. But when it reached the open pasture at Joplin’s eastern edge, the tornado—as if it had been fueled by manmade structures and was now depleted—delivered a few dying spasms and vanished.

* * *

My wife and I were eating dinner at home in Brooklyn when we heard the news. Her sister called: There had been a tornado, and it sounded bad. Growing up in Joplin means growing up with tornado warnings, so I was certain this was yet another false alarm. Still, we moved to the couch and turned on the Weather Channel. Mike Bettes, one of the network’s on-camera meteorologists, was standing in a field of debris, talking to dazed Joplinites whose homes had just been leveled. At first we thought the crew was filming outside of town, in the country. A couple of houses down? Not so bad for late May in southwest Missouri. Then the camera turned and landed on St. John’s Hospital. Windows blasted out, every surrounding structure demolished, it looked like the backdrop from a high-budget zombie movie. The hospital is in the middle of town. It’s also about half a mile from my dad’s house. On camera, Bettes choked up, turned his head, and broke into tears.That’s when we freaked out.

We started calling, texting, posting urgent Facebook messages asking family and friends for information. I haven’t lived in Joplin since I left for college, but my parents, grandparents, and plenty of aunts, uncles, cousins and old friends still live in the area. Same goes for my wife, another Joplin native. No phone calls were getting through, but our parents texted back quickly: They were fine, and so were their homes. Throughout the evening it became obvious that the storm was extraordinarily severe. Nonetheless, it wasn’t until the morning that we realized that the damage reports that had been streaming in over Facebook weren’t isolated. One continuous stream of demolition connected them all.

The tornado destroyed 20 percent of the property in Joplin, killed 161 people, and injured 1,150 more, all in a town with just 49,000 residents. That doesn’t quite make it the deadliest tornado in history. The worst was the Tri-State tornado of March 18, 1925, which in three and a half hours killed 695 people in Missouri, Illinois and Indiana. But because the Tri-State tornado (and the other five storms responsible for more deaths than the Joplin tornado) happened before the invention of modern weather-monitoring instruments, it’s unclear whether they involved single funnel clouds or entire swarms. As a result, the Joplin tornado is the deadliest single tornado on record.

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No Shelter

No Shelter

The tornado that swept through Joplin last year destroyed 6,954 houses and killed 161 people, in 32 minutes.

The citizens of Tornado Alley towns like Joplin long ago adapted to the region’s abusive weather by assembling warning systems, building shelters, and instructing children in siren interpretation and shelter taking from the earliest days of elementary school. But adaptation and instruction can only do so much. As towns like Joplin have grown, subdivisions sprawling into soybean fields, they have become larger targets. A century ago, Joplin covered 12.5 square miles. Now it occupies 35 square miles. Building codes, meanwhile, aren’t written with storms even remotely as strong as the May 22 tornado in mind. Plenty of homes and businesses get built that would have a hard time withstanding the atmospheric strains of a terrarium. Houses are frequently built on slab foundations, with no basement in which to ride out a tornado. Many businesses are no better. A larger-than-average percentage of the deaths caused by the Joplin tornado happened in commercial buildings, including big-box retail stores. Home Depot said that its Joplin store, which was demolished in the storm, was built properly and that no building could have survived the tornado—but it also said the company will be adding an underground storm shelter to its new store.

In the aftermath of the tornado, citizens, reporters and government officials scrutinized the warning system and promised to find out what went wrong. Did forecasters give people enough notice? Did the satellite and radar systems work as designed? Did anyone pay attention? I was more interested in the cause of the storm itself. For years I had been hearing unnerving weather reports from back home: news of 70-degree days in January, of droughts followed by floods followed by droughts, of ice storms causing power outages not seen in the area since the advent of electricity. Was this tornado, by far the most devastating natural disaster the area had ever experienced, part of a pattern? Was climate change causing this insane weather?

“With every landmark destroyed, some blocks seemed shorter than they had before; others longer.”I realized, as scientists dutifully reminded the press in the days after the storm, that it’s probably impossible to draw a causal link between any single weather event and climate change. But I couldn’t help but sympathize with the sentiment that Bill McKibben, a writer who has long argued that global warming is the single most important problem facing humanity, expressed that week in a Washington Post op-ed. The headline: “A Link between Climate Change and Joplin Tornadoes? Never!” Rather than making connections between the destruction in Joplin and the floods and fires and droughts happening around the world, he argued, “It’s far smarter to repeat to yourself the comforting mantra that no single weather event can ever be directly tied to climate change.”

When I read McKibben’s column, I was in the middle of clearing my schedule and booking a trip back home. His sarcasm seemed to come from a place of exasperation that I happen to share—a frustration with the odd American reluctance to consider the possibility that climate change is not only real, but already contributing to disasters like the one in Joplin.

* * *

A week after the tornado, I set out with my dad in his pickup truck to retrace the storm’s path. We started on the road west of town where storm chasers filmed those first portentous clouds. As we drove east, we encountered the first signs of damage—power lines askew, tree limbs down. The wounds soon became more traumatic. In a newish subdivision we saw the first real structural damage, a ranch-style home with a semi-collapsed garage. Above the garage door, a warning was scrawled in silver spray paint: “Looters will be shot!”

The destruction came into cinematic view as we crested a hill on West 26th Street, which overlooked St. John’s. The storm had established new vistas, shaving away the houses and trees that had previously defined the skyline. Debarked trees, blond like treated lumber, splintered the horizon. We stopped to make sense of the view. To our right, two flower-covered crosses, one pink, one blue, stood at the threshold of a vanished home.

We got back in the truck and continued east, passing through neighborhoods that contained childhood homes, friends’ childhood homes, elementary and middle and high schools. On the flight home, I had braced myself for this part. I had expected to look on the ruined landscape of my youth with sadness and nostalgia. But I was acutely aware that compared with the people fishing family photos from the rubble, I could not complain. It also turned out that the terrain was too disfigured to trigger many memories.

The town was so unrecognizable that one of the first tasks workers undertook, after clearing the streets of rubble, was painting street names onto the pavement at every intersection. The signs were gone, as were the landmarks, and even lifetime residents were finding it difficult to navigate. Some blocks seemed shorter than they had before; others, longer.

The major streets were clogged with emergency workers, police officers and other rubberneckers like me. Search-and-rescue crews had spray-painted the sides of damaged houses with tic-tac-toe-looking code that indicated that a house had been checked for bodies. Many were marked with a final message: “OK to Doze.”

We soon arrived at another hill, this one overlooking the high school, from where we could see the mile and a half to Range Line Road, a new sight from this part of town. We stopped to walk around in the now empty neighborhood near the school. We inspected a heap of rubble on the edge of the high school’s practice soccer fields, which was loaded with projectiles—nails, bricks, bolts, hunks of lumber and a manhole cover that I imagined flying around in the tornado like some Frisbee of Death.

We drove through the damage for another four miles or so, until the trail of debris ended as abruptly as it had begun. The sight of still-standing trees on the east end of town was a relief. Altogether the tornado destroyed 6,954 homes and caused at least $3 billion in damage. In the following weeks, the city would begin bulldozing the structures that were beyond repair. Dump trucks would cart away some 1.5 million cubic yards of rubble, depositing most of it in a landfill near the abandoned lead and zinc mines west of town.

Tornado Forming
Tornado Forming AP Photo/

Later that night, my dad and I talked about how the tornado would reshape Joplin. “When you come back a year from now,” he said, “there’s going to be a strip of open pasture running through the middle of town.”

And then what? My stepmother, a real-estate agent, predicted that in the process of rebuilding, landowners would combine small, old lots into larger plots that could hold the McMansions 21st-century Missourians have come to love and expect. Yet by the time those homes were built, plenty of former Joplinites would surely have relocated for good. All week she had been selling houses to dislocated residents who were desperate to find a place to live. Elderly couples who hadn’t moved in 50 years were buying new homes sight unseen. Houses in Joplin are generally cheap and abundant, but now there weren’t enough to go around.

* * *

Meteorologist once thought it was impossible to predict a tornado and, even if it weren’t, that warning the public could cause mass panic and do more harm than the weather itself. Then on March 25, 1948, Ernest J. Fawbush and Robert C. Miller, meteorologists at the Tinker Air Force Base in central Oklahoma, issued the first tornado forecast, predicting more than three hours in advance that a squall line headed for the base was likely to produce a twister. Sure enough, a tornado ripped through the base three hours later, making Fawbush and Miller look like geniuses. Three years after that, the two founded the Severe Storms Forecast Center at Tinker, where their continued success in predicting storms made them moderately famous. As the Saturday Evening Post put it in 1951, the Fawbush-Miller system meant that “the Oklahoma farmer who said he always depended upon flying cornstalks and bed quilts to warn him of an approaching twister will now have ample time to walk—not run—to his ‘scarehole.'”

Fawbush and Miller’s bureau has since grown into the National Weather Service’s Storm Prediction Center (SPC), which issues watches for severe thunderstorms and tornadoes nationwide. “We are to tornadoes as the National Hurricane Center is to hurricanes,” says Greg Carbin, a warning-coordination meteorologist at the SPC. “We’re the national center of expertise related to severe-storm forecasting across the continental United States. But unlike the Hurricane Center, we really don’t have a season.” Using two geosynchronous satellites and a nationwide network of approximately 120 Doppler radar stations, forecasters watch for the conditions that spawn severe thunderstorms and tornadoes—typically a mixture of dry, cold air from the west with warm, moist air from the south. Carbin and his colleagues can often tell days in advance when weather conditions will be right for tornado formation. When a tornado seems likely, the agency hands responsibility over to local Weather Forecast Offices, which use radar to look for the telltale “hook echo” emitted by radio waves bouncing off a tornado’s cyclonic winds. If forecasters detect it, they upgrade the tornado watch to a tornado warning.

The system usually works pretty well. Carbin says that several days before the other great tornado disaster of 2011—the epic three-day outbreak that began on April 25, in which at least 178 individual twisters swarmed the American Southeast, killing 321 people—forecasters could see that in a few days, the atmosphere would be primed for a massive tornado outbreak. “We knew this was a bad deal,” Carbin says. Still, no matter how far in advance forecasters see tornado-ripe conditions forming, predicting the time and place an individual funnel cloud will form is profoundly more difficult.

“If it’s impossible to prove causation, it’s easy to see a disturbing correlation.”The Joplin tornado, unlike the April outbreak, gave little warning. “Joplin was a typical May severe-weather day on the Southern Plains,” Carbin says. “Why that particular storm formed in southeast Kansas and why it evolved the way it did—it’s not something you’d be able to pick out and say: This is the storm of the day.”

Until late in the afternoon on May 22, forecasters were saying that severe hail was the likeliest threat from the thunderstorm brewing over the Central Plains. Then at 5:17 p.m., after coordinating with Carbin’s team in Norman, Oklahoma, the Storm Prediction Center in Springfield issued the tornado warning that TV and radio stations in Joplin broadcast to their viewers and listeners. The system gave the people of Joplin 24 minutes of warning—enough notice to qualify the Joplin storm as well warned.

Still, in June, when a team of National Weather Service meteorologists traveled to Joplin to interview survivors and extract lessons from the chaos, they found problems. To some extent, local warning agencies and the NWS crossed signals, which may have caused confusion among the public. But the biggest concern was what the investigators called siren fatigue.

Like many other towns, Joplin’s policy is to sound a three-minute siren when a storm with winds stronger than 75 mph is approaching town, regardless of whether an NWS agency has issued a watch or warning. So at 5:11 on May 22, after local emergency managers were informed that a funnel cloud had been sighted over southeast Kansas, the city sounded a siren. But warning too early can be dangerous, particularly in a siren-jaded area. The NWS study describes one man’s confused, lackadaisical response: “(1) Heard first sirens at 5:11 p.m. CDT (estimated 30–35 minutes before tornado hit). (2) Went to the TV and heard NWS warning from TV override that indicated tornado near airport drive seven miles north (polygon #30) of his location. (3) Went on porch with family and had a cigar.”

Twenty-seven minutes later, the man heard another set of sirens. At this point, he “thought something wasn’t right,” so he went back inside and turned on the TV, where meteorologists were still warning that the threat was north of town. Then his wife yelled “Basement!” The report concludes this summary of events thusly: “Tornado hit as they reached the top of the basement stairs, destroying their home.”

If I had been living in Joplin that day, I probably wouldn’t have thought to go to the porch and smoke a cigar. But I almost certainly would have walked outside and looked at the sky. Only when the horizon turned green and the dogs began howling would I have hurried to the basement.

One way to fight warning fatigue could be using sirens with different pitches or rhythms to warn of different events. The idea that such an adjustment might be necessary seemed to annoy Bill Davis, head of the NWS forecast office in Springfield. “A warning is a warning,” he vented to the Joplin Globe. “How many adjectives and adverbs do we have to use to make the point that there’s a possibility you could die?”

Dennis S. Mileti, a University of Colorado sociologist who has studied public warnings, has explained that none of this should have surprised the NOAA researchers. “Most people rarely, if ever, experience nature’s extremes in the form of natural and other disaster types,” Mileti has written. “The result is that most people do not perceive risk. Instead, most think they are safe from nature and other violent forces.”

* * *

The most natural way to determine whether global warming is altering tornado patterns is to look for changes in tornado statistics and then see whether climate models can explain those changes. But the lack of reliable historical tornado data makes this kind of study challenging at best. And tornadoes are poorly understood to begin with. Scientists still aren’t entirely sure why one particular rotating thunderstorm transforms into a funnel cloud while another one doesn’t.

Warming Trends: Climate scientists are increasingly able to draw lines that suggest a correlation between climate change and extreme weather events. Causation is more complex, but faster computers and better models are beginning to point to a connection—a task that’s easier with temperature extremes than it is with tornadoes.
Scientists call the process of spotting climate variability and attempting to isolate the contribution of man-made climate change “detection and attribution.” Researchers have been doing detection-and-attribution studies on well-understood, well-documented phenomena such as temperature changes and rainfall patterns for more than a decade.

Nonetheless, even scientists who believe that climate change is likely to lead to more events like the Joplin tornado hesitate to draw conclusions about what is going on with the weather right now. In the days after the storm, the editors at the environmental website Yale Environment 360 asked several climate experts to answer the question: Is extreme weather linked to global warming? Andrew Watson, a professor of environmental sciences at the University of East Anglia in England, responded, “My answer to this question as posed is no. However, if you were to ask instead whether I expect that human-caused climate change will lead to more extreme weather events, the answer would be yes.”

This type of reticence surely comes in part from healthy scientific skepticism—the hesitancy to overinterpret data and the impulse to accumulate decades’ worth of statistics before drawing conclusions. But it also seems likely that climate scientists are triply cautious with their public statements because of they way they’ve been dragged into the culture wars. Recall that the university where Andrew Watson works was implicated, and then vindicated, in the phony scandal called Climategate, in which skeptics used out-of-context bits from stolen e-mails to make it sound as if researchers were engaged in some great conspiracy. Climate scientists have become the abortion doctors of the scientific establishment: maligned, ridiculed, harassed, and even physically threatened. Several climate scientists in Australia, which had been debating a tax on carbon emissions, received so many death threats that their universities moved their offices to “secure facilities.”

Kevin Trenberth, a senior scientist at the Climate Analysis Section of the U.S. National Center for Atmospheric Research, is more willing than most climate scientists to link current extreme weather with climate change. He explained to me that climate change is not directly causing events such as the Joplin tornado. It is, however, “loading the dice” by increasing the amount of energy in the atmosphere, making events that would occur naturally all the more powerful and violent.

The argument is based on simple thermodynamics: As the atmosphere warms, it holds more moisture. Since 1970, atmospheric water-vapor concentrations have increased by 4 percent. That additional moisture is fuel for storms. Day to day, Trenberth says, the effect of the increased water-vapor concentration is modest, but over time the accumulated changes result in a “magnifying effect” of 5 to 10 percent. “That’s often enough to make this thunderstorm into a supercell storm, or to create new records,” he says.

“That week local kitchens and dining rooms had a way of turning into impromptu PTSD support groups.”Trenberth has been working on this thesis since the late 1990s, and although scientists increasingly accept his argument, many are still hesitant to go as far as he does. As he told the climate writer Joseph Romm in 2010, soon after so-called thousand-year floods soaked Tennessee, the link between present-day extreme weather and well-established climatic trends “often gets underplayed by my fellow scientists.”

Determining whether climate change caused, or even worsened, an individual tornado seems to be beyond the epistemological limits of science. But if it’s impossible to prove causation, it’s easy to see a disturbing correlation. Climate change is happening; climate change should make many types of extreme weather more intense; extreme-weather events are already becoming more common. “The warning signs are there,” Trenberth says.

* * *

While I was on my way back to Missouri, a friend sent a Facebook invitation to the newly created “Joplin Expatriates” group. It was an open call to a local bar for Saturday night, six days after the storm: “A Date for Destruction: Let’s Get Drunk!” I RSVP’d yes, with a note that said I expected to need a drink after seeing the destruction. “You will need five,” someone posted in reply.

By the day of the gathering, the disaster zone was festering. The air carried the smell of rotting meat, fiberglass insulation, chainsaw exhaust, burning plastic and the kind of mold that requires you to tear all the drywall out of your house. Now and then, sawdust sprayed from fresh-cut tree limbs freshened the breeze. Cleanup-crew volunteers had spent the week helping people search their destroyed homes for heirlooms before the rubble was bulldozed into a heap.

Many of those volunteers, among them my oldest and greatest friends, were at the bar. Spirits were surprisingly high. After a cursory discussion of our impressions of the damage—”Can you believe this?” “No, not really”—conversation turned to reunion-style catching up. In a way, it felt like December 23, when native sons and daughters, back in town for Christmas, sneak out to meet friends in the still-unregulated cigarette smoke of Joplin dive bars.

Even so, that week local kitchens and dining rooms had a way of turning into impromptu PTSD support groups. One night at my dad’s, a neighbor who had spent the evening of the tornado volunteering in an emergency room described an array of horrors: an elderly woman, fully conscious, whose scalp was peeled back, exposing her skull. Another victim whose jaw had been torn halfway off. Still-living victims who emergency workers decided to black-tag, leaving them to their death so they could devote their limited time and resources to helping people who had a chance of surviving.

Another night, after dinner, my mother’s boyfriend told the story of the 12-year-old girl he met at the hospital where he was helping out. She had been in the AT&T store on Range Line when the tornado hit. During the storm, she was separated from her family. Strangers brought her to the hospital. My mother’s boyfriend stayed with her through the evening and tried to help her find her family. No one had any idea where they were. At the end of his volunteer shift, the fate of the girl’s family was still a mystery.

December 5, 2011 Aaron Fuhrman

Within each of these horror stories was a reassuring fact: As soon as the storm hit, people scrambled to help other people. Scientists have long known that disasters have the unexpected effect of producing what sociologist Charles Fritz characterized in his 1961 study “Disasters and Mental Health: Therapeutic Principles Drawn from Disaster Studies” as “mentally healthy conditions.” Perhaps because disasters force the people living through them to focus on the present and forget their anxieties about the past and future, human beings tend to keep it together better in the middle of apocalypse than they do during the average morning commute.

* * *

The U.S. Global Research Change Program, a federal project charged with determining how climate change will manifest itself in America, has predicted that in the coming decades the middle of the country will become hotter and drier, while the East will get wetter—and everywhere, the rain that does fall will fall more heavily. This very likely is already happening. Last year, the U.S. experienced its hottest summer in 75 years. In Joplin, as cleanup crews bulldozed homes and hauled away the debris, the temperature set new records almost daily, reaching an unnerving high of 110°F. The heat and drought were even worse to the south; Texas experienced the driest year in history. Yet for five states in the Northeast, 2011 was the wettest year on record. Earlier in the year, Illinois, Indiana, Kentucky, Ohio, Pennsylvania and West Virginia all recorded their wettest April in 116 years. The Mississippi River flooded three million acres in three states. In September, after Hurricane Irene soaked the East Coast, topsoil from flooded farms upstate turned New York Harbor the color of Yoo-hoo. The federal Disaster Relief Fund diverted money from the Joplin relief effort to help pay for that flooding.

“Last year, the U.S. experienced its hottest summer in 75 years. In Joplin, as cleanup crews bulldozed homes and hauled away the debris, the temperature set new records almost daily, reaching an unnerving high of 110°F.”The meteorologist Jeff Masters wrote on his blog, “Any one of the extreme weather events of 2010″—a year whose litany of disasters reads much like last year’s—”or 2011 could have occurred naturally sometime during the past 1,000 years. But it is highly improbable that the remarkable extreme weather events of 2010 and 2011 could have all happened in such a short period of time without some powerful climate-altering force at work.”

Despite all of this, a Pew poll conducted in 2010 found that just 59 percent of Americans think there is solid evidence that the planet is warming—and that’s down from 79 percent in 2006. Only 27 percent of Americans surveyed in a different poll said climate change was their greatest environmental concern.

In 2009, 29 scientists published a paper in the journal Nature titled “A Safe Operating Space for Humanity.” In it, they listed a series of data points that will determine whether the planet remains habitable. The highest “safe” concentration of carbon dioxide in the atmosphere is 350 parts per million. The current level is 387 ppm, and it is increasing by 2 ppm annually. There’s no reason to believe that trend will reverse or even slow down anytime soon. In 2010, as the weather became increasingly catastrophic, carbon-dioxide emissions increased by the largest percentage ever recorded.

In Joplin, a common explanation for abnormal weather is “It’s all cyclical.” These things have happened before, and they will happen again. But this explanation ignores an uncontestable fact: The world is different now than it was when the Tri-State tornado hit, or when the Great Plains became a dust bowl. We’re the ones who changed it. The process we’ve set in motion is unpredictable enough that we can’t know for certain what kind of world we’ll have in 20 or 50 or 100 years. But we won’t be able to say we couldn’t have seen it coming.

This article originally appeared in the February 2012 issue of Popular Science.