Humans are incredibly resilient, able to survive in temperatures ranging from the freezing Arctic to scorching Sahara. But still, there are limits to what our bodies are able to take. According to a recent study, the climate in the Persian Gulf will soon surpass these limits. Soaring temperatures are expected to drive human populations from the region within a century, but certain demographics may be affected even sooner.

The effects of climate change can be felt on nearly every continent, from rapidly increasing sea levels in North America to the disappearing glaciers on Mount Kilimanjaro in Africa. However, certain geographic features in the Persian Gulf make the region especially vulnerable to the effects of rising temperatures. Cloudless summer skies, for example, allow the sun’s heat to reach the Gulf ocean more easily. With shallow water in the Gulf, it takes less time to heat up the ocean.This results in increased humidity throughout coastal areas, The Guardian reported. Humidity is the amount of water vapor in the air, and it interferes with the body’s ability to naturally cool itself by slowing down sweat from evaporating, making the heat even more dangerous.

For the recent study, published in the journal Nature Climate Change, a team of researchers from MIT and Loyola Marymount University created a model to see how current rates of climate change would affect the Gulf region in the not-so-distant future. To measure the limits needed to sustain life, the scientists used a measurement called “wet-bulb temperature,” which essentially determines the lowest temperature capable of evaporating water into the air by wrapping a thermometer in a wet cloth — in other words, it acts like our skin to determine how well we can cool ourselves by sweating.

The scientists found that without artificial cooling, such as air conditioning, the average human would survive no longer than six hours in temperatures above 95 degrees, or about 165 degrees using the National Weather Service’s “heat index,” which factors in humidity to suggest how hot it feels. The model revealed that soon, many major cities in Abu Dhabi, Dubai, Doha, Iran, and Saudi Arabia would exceed this threshold, with heat indexes of 165 to 170 degrees, according to a press release. The combination of humidity and heat would create a climate that has “never been reported for any location on Earth,” and could make the entire Gulf completely uninhabitable “even for the fittest of humans,” Elfaith Eltahir, a researcher involved in the study, told The New York Times.

Most Affected

Although the study said it’ll be nearly 100 years before the climate in this region exceeds this threshold, recent weather reports suggest the Gulf could become a health hazard to some demographics even sooner. This past summer in Iran, for example, a week-long heat wave’s peak temperatures missed reaching this threshold by only a fraction of a degree. Some of the first to be affected by the worst of the summer heat waves may be the millions of Hajj pilgrims who travel to Mecca in Saudi Arabia.

“One of the rituals of Hajj — the day of Arafah — involves worshipping at the site outside Mecca from sunrise to sunset. In these kind of conditions, it would be very hard to have outside rituals,” said Eltahir, according to The Guardian.

Along with pilgrims, the temperatures may soon be especially dangerous for the less-wealthy Gulf residents. While wealthier countries will likely be able to afford the air conditioning needed to protect people from the heat, the report suggests that less affluent countries, such as Yemen, would be less able to deal with such a crisis. The study suggested that without protection, these temperatures would also be especially dangerous for the weakest members of society, “namely children and the elderly,” the report read.

Thankfully, we have not yet reached the point of no return. The scientists are hopeful that curbing greenhouse emissions could stall the onset of these extreme temperatures.

Source: Pal JS, Eltahir EAB. Future temperature in southwest Asia projected to exceed a threshold for human adaptability. Nature Climate Change. 2015.