By the end of this century, climate change could drive temperatures up in the Persian Gulf to levels that humans cannot tolerate, a study suggests.
Without successful efforts to limit greenhouse gas emissions, some Middle Eastern cities could experience a combination of temperatures and humidity in excess of what humans can survive, researchers say their simulations show, Tech Times reported.
Heat waves are, of course, not uncommon in the world, but they seem to be increasing in severity. Earlier this year, sustained temperatures approaching 48 degrees Celsius (118 degrees Fahrenheit) in India led to the deaths of more than 2,500 people.
“The new study thus shows that the threats to human health [from climate change] may be more severe than previously thought and may occur in the current century,” says Christoph Schar of the Institute for Atmospheric and Climate Science in Zurich in a commentary on the study published in Nature Climate Change.
In that study, researchers warn that at least five of the Persian Gulf’s major cities could see summer weather so hot and humid, even healthy young adults could not withstand being out of doors for more than a few hours.
The problem, the researchers explain, would be the combination of high heat and elevated humidity. In high heat, the human body attempts to cool itself by sweating, with the perspiration carrying heat away as it evaporates.
However, humidity levels that are high enough to impede evaporation make it much harder for the body to cool itself, which can lead to the body completely losing the ability to regulate its internal temperature, a condition known as hyperthermia.
The threshold for that to occur is at least six hours of 95 degrees Fahrenheit on what scientists call the wet-bulb temperature scale, a combination of heat, humidity and air pressure creating severely muggy weather.
At sea level, a temperature of 47° C (116° F) combined with 50% humidity—producing a heat index of 80° C (177° F)—would reach that threshold, researchers say.
Computer models show that, by the year 2100, five cities—Bandar Abbas in Iran , Abu Dhabi and Dubai in the UAE, Doha in Qatar and Dhahran in Saudi Arabia—could experience heat waves hitting that threshold and beyond.
The Persian Gulf, with its shallow waters that increase heat absorption and the already intense heat from the sun, is “a specific regional hotspot where climate change, in absence of significant mitigation, is likely to severely impact human habitability in the future,” the researchers say.
Climate Action Plan
The bouts of heat would hit productivity, stopping construction, fishing and support activity for oil and gas rigs in the Persian Gulf.
That is under the assumption global warming follows the business-as-usual scenario outlined by the UN climate science panel, with temperatures rising an average of 4-6° C from pre-industrial levels by 2100, Climate Change News reports.
Carbon-cutting pledges submitted by over 150 countries toward a new global warming treaty would limit warming to 2.7-3.5° C, according to more recent analyses.
Of the Persian Gulf states, only Oman and the UAE have so far provided domestic climate plans. OPEC nations, including Iran and Saudi Arabia, the top carbon polluters yet to present a pledge, will deliver before the Paris summit, Reuters reported.
Oman offered a 2% cut in greenhouse gases below forecasts of emissions growth by 2030. The UAE did not set an emissions target at all, but said it would get a quarter of its energy needs from clean sources by 2021.
National pledges will form the basis of a UN climate deal to be finalized in Paris this December.
