Scientists claim that parts of the Persian Gulf could become so hot and humid that spending even a few hours outside could present a health hazard.

A new study published on Monday reveals that because of human contribution to climate change some Middle East cities “are likely to experience temperature levels that are intolerable to humans,” writes Josh Schwartz for The New York Times.

Unbearable Heat Could Be The Norm In Middle East By 2100

Deadly combination of heat and humidity could occur in Middle East

A combination of high temperatures and humidity levels could mean that the human body can no longer regulate its temperature by sweating. For those who do not have access to air-conditioning, the results could be fatal. There could be devastating consequences for many poor people in the Gulf, as well as those who work outdoors in professions like agriculture and construction.

The journal Nature Climate Change published the paper, written by Jeremy S. Pal of the department of civil engineering and environmental science at Loyola Marymount University in Los Angeles and Elfatih A. B. Eltahir of the Massachusetts Institute of Technology. Previous research floated the idea that these conditions could be reached within 200 years, but that time has been halved with this new research.

While some people bemoan the heat, others say the greatest enemy is humidity. Pal and Eltahir claim that is in fact both. They used the wet-bulb temperature to measure atmospheric decisions, a method which describes how far evaporation and ventilation are capable of lowering the temperature of an object.

Even fittest people could find life endangered

When the wet-bulb temperature reaches 35 degrees Celsius, a person who is soaked in sweat can no longer cool down. By way of comparison, weather forecasters sometimes use heat-index measurements to tell viewers how hot a day will “feel.” A wet-bulb temperature of 35 degrees is roughly equivalent to 74 degrees on the heat-index.

Heat waves often cause thousands of deaths, mainly among the young, elderly and infirm, and these numbers will only rise should temperatures increase. The scientists predict that these extreme conditions “would probably be intolerable even for the fittest of humans, resulting in hyperthermia” after six hours of exposure.

Erich M. Fischer, senior scientist at the Institute for Atmospheric and Climate Science at the science and technical university ETH Zurich, explained the role of humidity. Fischer was not involved in the study.

“Anyone can experience the fact that humidity plays a crucial role in this in the sauna,” he said. “You can heat up a Finnish sauna up to 100 degrees Celsius since it is bone dry and the body efficiently cools down by excessive sweating even at ambient temperatures far higher than the body temperature. In a Turkish bath, on the other hand, with almost 100 percent relative humidity, you want to keep the temperatures well below 40 degrees Celsius since the body cannot get rid of the heat by sweating and starts to accumulate heat.”

Global efforts to slow climate change could avert catastrophe

The seas of the Middle East are warm, encouraging these extreme combinations of heat and humidity. There are also concerns over the future of the hajj, the annual pilgrimage which sees around 2 million Muslims travel to Mecca, Saudi Arabia. “This necessary outdoor Muslim ritual is likely to become hazardous to human health,” the authors predicted.

All is not lost, however, and the world can still reduce the impact of climate change by reducing greenhouse-gas emissions. “Such efforts applied at the global scale would significantly reduce the severity of the projected impacts,” they wrote.

“The threats to human health may be much more severe than previously thought, and may occur in the current century,” wrote Christoph Schär, of the Institute for Atmospheric and Climate Science at ETH Zurich.

Scientific peers claim research is worthy of analysis

In July this year temperatures almost reached the 35-degree wet-bulb threshold, at 34.6 degrees. “It is credible that it will sometimes rise above 35 °C within this century,” he wrote.

Dr. Fischer told The New York Times that he found the research “robust and noteworthy,” but there were some doubts over temperature measurements and models. “Whether it exceeds or just gets close to the adaptability limit and for what period (which is probably quite relevant) may need further research,” he wrote.

Steven Sherwood previously released research that claimed some areas of the globe could be uninhabitable within 200 years, and said that the results of this latest study were trustworthy. However he did argue that “we really need to learn how to improve these models” to improve confidence in the research.

He called the revelation that many Gulf cities would be uninhabitable for those without air conditioning “truly shocking,” and pointed out the irony “given the region’s importance in providing fossil fuels.”