There’s an old Jon Stewart stand-up bit about spending time in Arizona during the height of summer, and the cooling nozzles built into some buildings there that go off intermittently to spray a cooling mist on the unlucky bastards stuck outside in the desert heat. Steam rises from the streets as the water hits them, and Stewart wonders—while walking through the hot, red, sun-burnt city during the blistering midday heat—if he’s even still on planet earth. How do people live here?, he asks himself.
Well, soon, at least in some cities on the Arabian Gulf, people may not be able to anymore. A new study released Monday in the journal Nature Climate Change suggests that some cities there will “exceed a threshold for human adaptability,” possibly by as early as 2100. They will, as the Washington Post succinctly put it, “literally be too hot for human survival.”
Many metropolises in the region—Dubai, Abu Dhabi, Doha, and, perhaps most distressingly, the Saudi holy city of Mecca—could be affected. Critically, they might exceed a “wet bulb” temperature—a measure of actual air temp and the moisture the air contains—of 95 degrees Fahrenheit during summer months, or a heat index of 170, according to the authors of the study. That’s important, because when “wet bulb” temps rise to that extent, the body can lose the ability to cool itself by getting rid of excess heat via sweat, or even by seeking shade. At these temps, the body takes on the excess heat instead of shedding it, and those outside risk heat stroke, hyperthermia, and, ultimately, death.
The report was authored by a pair of scientists—Jeremy Pal and Elfatih A. B. Eltahir, from Loyola Marymount University and Massachusetts Institute of Technology, respectively—who write, “Our results expose a regional hotspot where climate change, in the absence of significant mitigation, is likely to severely impact human habitability in the future.”
The study projects “an ensemble of high-resolution regional climate model simulations that extremes of wet-bulb temperature in the region around the Arabian Gulf are likely to approach and exceed this critical threshold under the business-as-usual scenario of future greenhouse gas concentrations.” That’s a science-y way of saying unless we curb carbon emissions soon, before too long the sun in the Arabian Gulf will be hot enough to actually murder you.
Most concerning to Pal and Eltahir are the potential ramifications for the Hajj, the Islamic pilgrimage to Mecca undertaken by millions each year.
“This necessary outdoor Muslim ritual is likely to become hazardous to human health, especially for the many elderly pilgrims, when the Hajj occurs during the boreal summer.”
The Arabian Gulf is built for extreme heat. It regularly has clear skies, and sports relatively shallow seas, which absorb heat and release water vapor that retains heat near the ground. This past summer Bandar Mahshahr in Iran came close to experiencing a wet-bulb temp of 95 F, falling just short at 94.28—an anomaly Pal and Eltahir’s study shows could soon become the norm.
Luckily, as the quote from the report above illustrates, these possibly lethal temperatures predicted in the Arabian Gulf will only occur if we continue “business as usual,” and steps aren’t taken to curb carbon emissions. Countries like India have pledged to reduce their carbon emissions 33 to 35 percent by 2030, and President Obama has urged large US companies to commit to cutting emissions, and has also announced historic carbon pollution standards for power plants. With the annual United Nations Climate Change Conference scheduled to begin on November 30 in Paris with the stated objective of achieving a “legally binding and universal agreement on climate” from all nations, there may still be some hope for future generations to stand outside in Dubai without dying.
This article originally appeared on Vice US.