How Humans Survive in Extreme Heat

How Humans Survive in Extreme Heat

The Middle East is the part of the world that's really cooking right now.
 
The region is being enveloped by a "heat dome" raising temperatures to near record-breaking levels, made all the more unbearable by power failures and sandstorms. Some of the most sizzling temperatures were recorded in the Iranian city of Bandar Mahshahr, which achieved a heat index of 74 Degrees Celsius, the second highest ever reported. What's worse is there doesn't seem to be any relief in sight, according to weather forecasts.
 
Entire cities are literally as hot as saunas right now. Saunas might have health benefits, but no one has ever tried to live in one. How could anyone survive such extreme temperatures over a sustained period? Is it even possible to breathe in those conditions?
 
Well, yes, breathing is possible, but not necessarily comfortable, experts say. The heat can change air quality, which in turn can affect those breathing that air.
The Ozone has almost like a sun burning effect on the airways of the lungs that tends to make the airways sometimes inflamed. They tighten up, so it becomes harder to get the air in and out"
 
The extreme temperatures can be particularly taxing on anyone with an underlying lung condition, such as asthma, COPD or emphysema. Even for people with normal lungs, doing activities outdoors in the heat of the day when ozone levels are high is not advisable.
 
So a person outside in extremely hot weather would be able to breathe, but probably with some difficulty. And breathing is in fact one of the ways humans cool down. The other is sweating, but that doesn't work as well when it's humid. While we tend to sweat more in humidity, which is why we often associate it with "sticky" heat, the moist air isn't evaporating sweat, and therefore doesn't produce a cooling effect.
 
Excessive sweating can lead to dehydration, fatigue and muscle cramps. This can add up to heat exhaustion. Eventually, all that lost water will lead a person to stop sweating and the ever-rising body temperature will stress internal organs.