This summer, a heat wave sent temperatures near the Persian Gulf skyrocketing, with outdoor temperatures reaching as high as 120°F throughout parts of Iraq and Iran. And while those temperatures might seem extreme, a new study published in Nature Climate Change suggests that scorching temperatures could become increasingly common in the region by the end of the century, if climate change is left unchecked.
According to the study, outdoor temperatures in the Persian Gulf could reach levels inhospitable to human survival as often as once every decade by 2100, with heat and humidity climbing so high that healthy humans couldn’t survive for more than a few hours outside. This would place a huge amount of stress on both poor residents, who cannot afford air conditioning or other adaptive measures, and laborers who work outdoors, like farmers and construction workers.
To understand how climate change could impact future temperatures and human health in the Persian Gulf, researchers from Massachusetts Institute of Technology and Loyola Marymount University used high-resolution climate models to look at a measurement known as the “wet-bulb temperature,” which takes into account both heat and humidity. Researchers chose to look at the wet-bulb temperature because of its direct impact on human health — for humans to maintain a healthy inner body temperature, the wet-bulb temperature cannot exceed 35°C (95°F). If the wet-bulb temperature does exceed that threshold, humans have a difficult time getting rid of metabolic heat, leading to hyperthermia and potentially death.
Still, the study notes that the worst of this extreme heat could be avoided if serious mitigation efforts are taken. Under a scenario where global emissions peak around 2040, and then decline, annual wet-bulb temperatures would not exceed the 35°C threshold at any of the considered locations.