A remote township in China's arid northwest endured temperatures of more than 52 Celsius (126 Fahrenheit) on Sunday, state media reported, setting a record for a country that was battling minus 50C weather just six months ago.
Ok, so it doesn’t mention wet bulb temperature anywhere, so I went to figure it out. The first thing I was surprised with is apparently most of online calculators don’t take in values higher than 50C.
I couldn’t find the exact data about humidity for that day, but it has been 35-40%+ at a minimum for most days in that region, sometimes even reaching 90%.
So, 52C at around 40% humidity is 37.5C in wet bulb temp. The point of survivability is around 35, and most humans should be able to withstand 37.5 for several hours, but it’s much worse for sick or elderly. 39 is often a death sentence even for healthy humans after just two hours — your body can no longer lose heat and you bake from the inside. That’s like having an unstoppable runaway fever. And with that humidity it’s reached at 54C.
Wet bulb temperature is basically converting to 100% humidity equivalent, so as you get closer to 100%, WBT approaches measured temperature. We use this metric because our bodies cool mostly via evaporation, and no evaporation is possible at 100% — the air is already fully saturated. So in general, WBT means minimum possible temperature that can be reached by evaporative cooling. Once your body loses the ability to cool, it rushes to match surrounding wet bulb temperature (or even exceed it, since we produce about 100W of heat energy by simply existing).
So 52C at 90% is about 50C WBT. Survivable for mere minutes for some, and probably for about an hour or so for most humans. Definitely not survivable for a full day.
Ok, so it doesn’t mention wet bulb temperature anywhere, so I went to figure it out. The first thing I was surprised with is apparently most of online calculators don’t take in values higher than 50C.
I couldn’t find the exact data about humidity for that day, but it has been 35-40%+ at a minimum for most days in that region, sometimes even reaching 90%.
So, 52C at around 40% humidity is 37.5C in wet bulb temp. The point of survivability is around 35, and most humans should be able to withstand 37.5 for several hours, but it’s much worse for sick or elderly. 39 is often a death sentence even for healthy humans after just two hours — your body can no longer lose heat and you bake from the inside. That’s like having an unstoppable runaway fever. And with that humidity it’s reached at 54C.
We’re dangerously close to that.
Just out of interest, what would be the wet bulb temperature at 90% humidity? I’m not familiar with that temperature scale.
Wet bulb temperature is basically converting to 100% humidity equivalent, so as you get closer to 100%, WBT approaches measured temperature. We use this metric because our bodies cool mostly via evaporation, and no evaporation is possible at 100% — the air is already fully saturated. So in general, WBT means minimum possible temperature that can be reached by evaporative cooling. Once your body loses the ability to cool, it rushes to match surrounding wet bulb temperature (or even exceed it, since we produce about 100W of heat energy by simply existing).
So 52C at 90% is about 50C WBT. Survivable for mere minutes for some, and probably for about an hour or so for most humans. Definitely not survivable for a full day.