Late last July, a swath of the Middle East from Saudi Arabia across Kuwait to Iraq and Iran was hit by a heat wave. As usual, it was caused by a powerful high-pressure dome that parked overhead, compressing and heating the upper atmosphere, limiting convection, and trapping the lower atmosphere below it even as the desert floor heated the air from the ground up. “Heat waves” are relative affairs—technically, they are merely multi-day deviations from whatever the local norms happen to be. They don’t count for much in places like Denmark. The Middle East is not as milquetoasty as that. In Kuwait, for instance, the daily average maximum temperature in July is around 112 degrees, a level that would trigger urgent warnings in the United States but that in Kuwait is simply the expected weather.

The heat wave last July was different. The month started hellishly enough. At an automated weather station in a desert wasteland called Mitribah, in the country’s uninhabited North, the maximum temperature hovered around 114 degrees. Then the numbers started to climb, passing through 120 degrees on the 14th, topping 124 degrees on the 19th, and peaking at 129.2 degrees in the midafternoon of July 21, 2016. That temperature exactly matched the highest reliably measured air temperature in history—129.2 degrees, recorded on July 1, 2013, in Death Valley, U.S.A. The Mitribah report made news around the world because of concerns about global warming, though no single temperature demonstrates much, and it is actually the accelerating rise of pre-dawn minimums, rather than the slower rise of midafternoon maximums, that is affecting global temperature averages more rapidly than scientists had anticipated just a few years ago.

To get this out of the way: among weather experts there is universal acceptance that global warming is a fact and that it is caused by human enterprise. As a result, dangerous heat waves are hitting with ever greater severity. In June, the National Weather Service warned of record-shattering heat in the American Southwest that it went so far as to label “crazy.” This is a trend that will continue worldwide, with lethal consequences, especially for the young, the old, outdoor workers, and the poor. Forget about hurricanes and blizzards, cyclones and floods: heat waves already cause by far the largest number of weather-related deaths—many thousands every year—and they are to be feared. Virtually no weather expert thinks otherwise. Nonetheless, when it comes to the 129.2 degrees recorded at Mitribah, the immediate regret within a subculture of observers is that the temperature did not rise higher. One of them, the renowned weather historian Christopher Burt, told me, “It came very close to breaking the record—just a tenth of a degree. That drives some people nuts!” Burt is 62. He writes for the Web site Weather Underground and is the author of a best-selling guide and record book titled Extreme Weather. He lives in the hills of Oakland, California, in a climate so benign that it becomes annoying. About the search for extremes, he said, “There is so much minutiae. I start to burn out on it sometimes. To give you some idea: the National Weather Service uses Fahrenheit and rounds off to the nearest degree. For the 129.2 in Death Valley, we have a photograph of the thermometer that clearly shows it, but officially the high was rounded down to 129 degrees. The Kuwaitis measure temperatures on the Celsius scale to the nearest tenth of a degree. That means that Mitribah, which was officially 54.0 Celsius, converted to 129.2 degrees Fahrenheit. So officially it beat Death Valley, even though we know that Death Valley matched.” He shook his head. He said, “Now what are you going to do? And actually this was the fifth time Death Valley went to an official 129 degrees. The four previous times no one took a picture of the thermometers—they could have been at 129.4. We don’t know.”

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Under Attack

Well, yes, we all know it’s true: once you go down the rabbit hole of accuracy, it is easy to lose yourself. A tenth of a degree here, a tenth of a degree there. Burt is a worldly man. He understands that the pursuit of accuracy, though necessary, can become an obsession, and that self-restraint is needed to keep larger truths in mind. No one lives in Mitribah, and it is unlikely that during the July heat wave anyone passed through. But merely 50 miles away lies Basra, Iraq, a city of more than 2.5 million people, a fifth of whom live on less than two dollars a day, and all of whom suffer from frequent power outages, particularly during heat waves. As in the rest of the overheated world, air-conditioning is out of reach for a large part of the population, and even traditional architecture offers little relief. Last July 22, one day after the Mitribah record, the temperature in Basra peaked at an atrocious 128.9 degrees. The extreme heat was not limited to just that one day: maximum temperatures had begun to rise above 100 degrees in early May, were exceeding 110 degrees by early June, and began regularly exceeding 120 degrees by the end of the month. Moreover, after the peak in July, the extremes continued relentlessly for all of August and September. Nighttime temperatures were cooler, but not much—typically they remained above a hundred until a few hours before dawn. It is known that periods of nighttime relief help to mitigate the peaks. Lack of them greatly increases the stress. The area of suffering was huge. Because of access to air-conditioning, it did not include wealthy Saudi Arabia or Kuwait, but it spread as far as Baghdad and into Iran. According to The Wall Street Journal, a Shiite cleric in Najaf claimed that Iraq and all of Islam were under attack by American electromagnetic weapons. Some Iraqi state meteorologists agreed that this was possible. Back in Oakland, at the center of the plot, Christopher Burt avoided the subject but could not help showing me the numbers. He said, “Look at this! Day after day after day! How can people survive these conditions?”

The short answer is that many people cannot. The human body sheds its internal heat and cools itself mostly through perspiration and evaporation, but only up to a point. There is no one temperature that defines the upper limit of safety, because the critical measure depends on humidity, physical activity, acclimatization, health, personal physiology, and—in war zones—such necessities as body armor. I know from travels in North Africa and the Middle East, as well as a week once spent in Yuma, Arizona, that at 110 degrees merely breathing begins to hurt. If people drink copiously, they can continue to function as long as the air is dry and the nights cool off. At 120 degrees, it is a different matter.

HEAT SEEKER

The prominent weather historian Christopher Burt in Bangkok, where he lived for many years. Photograph by Mathias Braschler and Monika Fischer.

Escape from Adrar

Years ago, when reporting from the Sahara in July, I decided to visit an Algerian oasis called Adrar, which has a local reputation for being one of the hottest towns in one of the hottest regions on earth. I had been visiting the desert for years and had seen some extremes but never the worst heat. I thought I should experience it. That was a mistake. I traveled to Adrar on a weekly regional flight in an old Air Algérie turboprop and arrived during a heat wave. The atmosphere was nearly opaque with suspended dust for the final 10,000 feet of descent. It was midafternoon. Stepping through the airplane’s door, I came under a shocking assault. In Adrar, the official air temperature—in the shade, at the standard shoulder height above the ground—was 119 degrees. On the airport tarmac, in direct sunlight, the air was obviously much hotter, but meaningless to measure. In town, there was a single, reinforced-concrete hotel with air-conditioning, and the air-conditioning had long since broken down. Given enough time, you could have baked a chicken in my room. A clerk recommended that I sleep on the roof, and I did, or tried to, in temperatures that did not settle below 100 degrees until the wee hours. At dawn, during the first, haunting call to prayer, the concrete roof was still warm to the touch. Then came the sun again. After an early-morning flurry of activity, the streets went dead as the residents sought shade to wait out the day. That night and the following one I abandoned the hotel roof and slept in a date-palm grove, where at least the dirt was cool at dawn. Around the fourth day I sensed that this was no longer just an uncomfortable experience but potentially a lethal one—it was that extreme. Cutting short the visit, I escaped by taking a succession of communal taxis across five days to the balminess of Tunis, on the Mediterranean Sea.