The Heat Will Kill You First: Life and Death on a Scorched Planet

by Jeff Goodell

WHEN HEAT COMES, it’s invisible. It doesn’t bend tree branches or blow hair across your face to let you know it’s arrived. The ground doesn’t shake. It just surrounds you and works on you in ways that you can’t anticipate or control. You sweat. Your heart races. You’re thirsty. Your vision blurs. The sun feels like the barrel of a gun pointed at you. Plants look like they’re crying. Birds vanish from the sky and take refuge in deep shade. Cars are untouchable. Colors fade. The air smells burned. You can imagine fire even before you see it.

(land reflects and amplifies heat much more efficiently than water),

I’d had little time to get acclimatized to the heat. I have since learned that after you spend a few weeks in a hot climate, your body makes subtle adjustments that help you better tolerate heat stress.2 Your normal deep body temperature drops. Your body sweats at a lower temperature, and so there is less strain on your heart, which keeps your heart rate from rising fast. At the same time, your heart pumps more blood per stroke. Your body retains more fluids and blood volume rises, increasing water reserves for sweating and cooling. But these changes are not permanent. “If you go out of the heat, within a few weeks all the adaptations go back to zero,” says Sam Cheuvront.

Good to know.

in most heat-related cases, people die of organ failure, which does not leave an easily detectable signature. Sometimes, an autopsy can find signs of internal bleeding or liver or kidney damage.

Humans became excellent hot-weather hunters. They could venture out in the heat of the day when other animals couldn’t, giving them a predatory advantage. By the time Homo erectus appeared about two million years ago, our ancestors were on their way to becoming endurance athletes, with long legs, nimble feet, and strong leg and hip muscles. With their superior heat management systems, they could literally run down an animal until it has heatstroke. This practice continues today. In the Kalahari Desert in southern Africa, modern hunter-gatherers are able to kill a kudu, a kind of antelope that is far faster than humans over short distances, by chasing it for hours in the middle of the hot day, until it literally collapses of heat exhaustion.

They WALK down animals. Bizarre to think about.

taste for spicy foods likely arose because before refrigeration, spices worked as a food preservative, which is particularly important in hot places where food spoils quickly. Garlic, onion, allspice and oregano are excellent bacteria killers, as are thyme, cinnamon, tarragon and cumin. “People who enjoyed food with antibacterial spices probably were healthier, especially in hot climates,” evolutionary biologist Paul Sherman said. “They lived longer and left more offspring. And they taught their offspring: ‘This is how to cook a mastodon.’”

In an Arizona heat wave, electricity is not a convenience. It is a tool for survival.

When a city like Phoenix goes dark, the comforts and conveniences of modern life fray. Without air-conditioning, temperatures in homes and office buildings soar. (Ironically, new, highly efficient LEED-certified buildings are tightly sealed, making them dangerous heat traps when the power goes out.)

As temperatures soar in the coming years, the real question is not whether superheated cities are sustainable. Phoenix is not going to melt into the desert and Chennai will not return to the jungle. The question is, sustainable for who? And at what cost? As cities grow and the heat rises, the future of Phoenix and Chennai, and many cities like them, is of a kind of temperature apartheid, where some people chill in a bubble of cool and others simmer in debilitating heat. This is not how you build a just, equitable, or peaceful world.

As the world heats up, it moves. This is true on the molecular level as well as on the species level. All creatures, from the ancient cedars of Lebanon to the microbes in the deep thermal vents at the bottom of the Pacific Ocean, have evolved within a basic temperature range, and if that range changes too much, they have to find a more habitable climate niche. For humans, the decision to stay or go from extremely hot places is often dependent on money, which buys access to cooling systems, clean water, and food.

Largely because of overfishing, 90 percent of the large fish that were here in the 1950s are now gone. One metric ton of plastic enters the ocean every four seconds (at this rate, there will be more plastic than fish in the ocean by 2050).

In 2022, the ocean hit its warmest temperature on record for the fourth year in a row.

Until now, the ocean has been the hero of the climate crisis—about 90 percent of the additional heat we’ve trapped from burning fossil fuels has been absorbed by it. “Without the ocean, the atmosphere would be a lot hotter than it already is,” Ken Caldeira, a senior climate scientist with Breakthrough Energy in California, told me. But the heat the ocean absorbed has not magically vanished—it’s just stored in the depths and radiated out later.

the idea that people who live in hot places are fundamentally better suited to heat than people who live in cold places is not true—at least, not in a simple and straightforward way.

of your skin make much difference. “Infrared radiation is primarily responsible for the heat build-up caused by sunshine, and dark skin and light skin absorb infrared radiation from the sun to nearly equal extents,” writes anthropologist Nina Jablonski in Skin: A Natural History. “By far the most significant factors in increasing a person’s heat load are external temperature, humidity, and the amount of heat the person generates as a result of exercise.”

as Larter, a veteran of many Antarctic crossings, put it with a wry smile, “There is always a storm on the way to Antarctica.”

Antarctica is the size of the United States and Mexico combined, with a permanent population of zero. It is not the territory of any nation, and it has no government, in the conventional sense.

it was not a garden-variety backyard mosquito. It was Aedes aegypti, an exquisitely designed killing machine that is one of the deadliest animals in human history. By one count, half the people who have ever lived have been killed by mosquito-borne pathogens.

The mosquito was a female—only females drink blood, which they need to produce their eggs.

Compared with other pathogens out there, Covid-19 is relatively docile. It is an easily transmissible virus that is far more deadly than the flu, and has mysterious long-term effects. But it doesn’t kill three out of four people it infects, like the Nipah virus. It doesn’t cause people to bleed out of their eyes and rectums like Ebola. “Imagine a disease with seventy-five percent case fatality that is equally transmissible,” says Stephen Luby, an epidemiologist at Stanford University. “That would be an existential threat to human civilization.”

Why are bats so good at harboring deadly viruses? For one thing, they have immune systems tolerant of infection that allow them to host a wide variety of viruses without getting sick. They live long lives (up to forty years), giving them plenty of time to spread disease. They are very mobile—some species range thirty miles or so each night in their hunt for food. And more important, as the climate warms, they can relocate.

As disease vectors, ticks are very different from mosquitoes. They live up to two years instead of a few weeks. But like mosquitoes, they are sensitive to changes in temperature and can’t survive long in cold or dry climates. As the world warms, they are following the heat. Some tick species are moving as much as thirty miles north each year—an unseen parade of bloodsuckers conquering new terrain. They are difficult to target with insecticides, and have many remarkable survival tricks, such as the ability to go long periods without water by basically spitting into a pile of leaves and then drinking it later when they are thirsty.

Lyme disease is emblematic of the threat ticks pose in a warming world. It is caused by deer ticks carrying the bacteria Borrelia burgdorferi. Lyme was discovered in Connecticut in the mid-1970s. Today it is a major, and growing, health threat. According to the CDC, reported cases in the US have tripled since the late nineties. Lyme disease has become an almost “unparalleled threat to regular American life,” as Bennett Nemser, an epidemiologist who manages the Cohen Lyme & Tickborne Disease Initiative at the Steven & Alexandra Cohen Foundation, has said. “Really anyone—regardless of age, gender, political interest, affluence—can touch a piece of grass and get a tick on them.”

As forests are cut up into suburban developments, the populations of foxes and owls decline, which leads to an explosion in the population of white-footed mice, which are the main reservoir for Borrelia burgdorferi. Young larval ticks feed on the infected mice, and then pick up Lyme and later spread it to anyone passing by.

This method is called vapor compression, and it’s more or less how air conditioners still work today. It is a technology that shaped the twentieth century just as surely as the internal combustion engine did, and has turned out to be just as durable, useful, and troubling for our future.

As Fred Hofheinz, the mayor of Houston in the 1970s, put it: “Without air-conditioning, Houston would not have been built at all. It just wouldn’t exist, that’s all.”

writer William Faulkner died of a heart attack in Mississippi at age sixty-four. “The first fact of the day,” wrote William Styron in an account of Faulkner’s funeral in Oxford, Mississippi, “aside from that final fact of a death which has so diminished us, is the heat, and it is a heat which is like a small mean death itself, as if one were being smothered to extinction in a damp woolen overcoat.” Styron described Oxford that day as a city drowned in “a heat so desolating to the body and spirit as to have the quality of a half-remembered dream, until one realizes that it has, indeed, been encountered before, in all those stories and novels of Faulkner through which this unholy weather—and other weather more benign—moves with almost untouchable reality.”

In his novel The Reivers, one of the characters grouses, “There are no seasons at all any more, with interiors artificially contrived at sixty degrees in summer and ninety degrees in winter, so that mossbacked recidivists like me must go outside in summer to escape cold and in winter to escape heat.” Faulkner was not the only one who saw air-conditioning as a technology from hell.

Love this. I hate how we over cool in the summer and overheat in the winter.

President Lyndon Johnson, who was a Texan, liked to crank up the air-conditioning and sleep under an electric blanket during sweltering DC summers).

We are constantly bombarded by images that suggest that if paradise does exist, it is warm and sunny.

Nobody should die in a heat wave. People die because they are alone and don’t know what to do and don’t ask for help. Or they don’t have air-conditioning (or the money to run it). Or they can’t get to a cooling center. Or they are afraid that their employer will fire them if they stop working. Moreover, people die because they don’t understand the warning signs of heat exhaustion and heatstroke or don’t take precautions and ask for help when those warning signs appear. There is so much ignorance and confusion about what to do in extreme heat situations.

“In Mississippi and the rest of the Deep South, heat waves already have two names: July and August.”

heat waves are the deadliest extreme weather events, killing far more people every year than hurricanes or floods.

In less than two weeks in 2003, fifteen thousand people in France died as a direct result of the heat wave. Nearly a thousand lived in central Paris. Many of the victims lived alone, in top-floor garrets, or attic apartments, where the heat built up beneath zinc roofs and literally cooked people as if they were in an oven.

Light colors increase the albedo, or reflectivity, of buildings, deflecting sunlight and causing less heat to be absorbed (there’s a reason why houses in hot places—Morocco, Portugal, the Greek islands—are traditionally painted white).

The fight between the past and the future defines the battle lines in many cities struggling to adapt to our fast-changing climate.

It’s our history, our culture, and our identity. But given the acceleration and urgency of the climate crisis, the harsh truth is, not everything can be saved.

Paris certainly needed more of them. Despite the city’s many parks, it has one of the lowest tree canopy covers of any city in the world—only 9 percent, compared with 18 percent in Boston and 29 percent in Oslo.

on a global scale, there are about three trillion trees on the planet—which works out to about 422 trees for every person on Earth. Humans are responsible for the loss of fifteen billion trees a year. About five billion new trees are planted or sprout annually, yielding a net loss each year of ten billion trees.

it’s going to take a long time to democratize shade.

it’s hard to argue that cities like Singapore, which have massive ecological footprints through their oil refineries and supply chains that stretch around the globe, actually contribute to the cooling of the planet. “Singapore can make itself into a garden because the farm and the mine are always somewhere else,” writes Richard Weller, a professor of landscape architecture at the University of Pennsylvania. “I would call Singapore a case of Gucci biodiversity, a distraction from the fact that they bankroll palm oil plantations in Kalimantan, the last of the world’s great rain forests.”

Descartes and Galileo, who were founders of the scientific method.

that’s the thing with cities. They may be superorganisms with their own metabolic flows, but unless you have an emperor like Napoléon III in charge or a power broker like Robert Moses, the urban planner who ruthlessly reshaped New York City in the mid-twentieth century, retrofitting takes time. And that’s assuming the city has the money and stable political leadership.

if I’d learned one thing on this Arctic trip so far, it was this: in a contest between fear and fatigue, fatigue usually wins.

Heat in a supposedly cold place is terrifying. Ice is a precision thermometer, registering the most minute changes. I felt it every day beneath my skis:

For polar bears, heat equals starvation. They depend on sea ice to hunt seals. When the sea ice is gone, they can no longer hunt.

The Arctic first appeared in the Western imagination in 330 BCE, when a Greek geographer and explorer named Pytheas left what is now the city of Marseilles and sailed for the Far North.

the unfortunate truth is that right now, the industrialized nations of the world are still dumping thirty-six billion tons or so of CO2 into the atmosphere every year, which is roughly ten times faster than has ever happened in Earth’s known history, even during past mass extinction events.

I was as alone with the world—alone with nature—as I had ever been. I’d look at the sky and the ice and scan the horizon and think about how fragile it all was.

This cold world was their Goldilocks Zone. But if I learned anything on my trip to Baffin, it was that their Goldilocks Zone was disappearing fast. Just like ours.