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Comment by rudedogg | Hacker News Reader

Little pedantic, but you meant "Wet-bulb" temperature (https://en.wikipedia.org/wiki/Wet-bulb_temperature#Temperatu...).

I only know from owning a swamp cooler.

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It is worth correcting, because I think most people haven't heard of wet-bulb, just as the methods and formulas that give us humidex "feels-like" temperatures aren't common knowledge.

A lot of ways we measure and describe the human experience of humidity and temperature are not standardized from location to location, so the non-local methods and terminology can be arcane for anyone who isn't a meteorologist.

I never heard of wet-bulb temp until carrot weather included it in a recent update.

Yes, that's right. I did mean wet-bulb. Not sure why my brain didn't register this mistake when I wrote it.

Isn't it basically the same as the dew point temperature? I believe a lot more people are familiar with that.

Just looking at the graphs, dew point temperature tends to be a bit lower than the wet bulb temperature (when humidity is equal).

No, dew point is the temperature of an object on which air will start to condensate (because cooling the given air to the dew point lets relative humidity rise above 100 %, i.e. condensation). Wet-bulb temperature is the lowest temperature an object can reach through evaporative cooling (i.e. humans).

The two are the same only if relative humidity is 100 %: 100 % relative humidity means that if the air cools at all, it will condensate; so the air temperature is the dew point. 100 % relative humidity also means that water cannot evaporate, as the air is already saturated with water, so the wet bulb temperature is also the same as the air temperature.

But that's the same isn't it, because condensation is a reversible process, as evaporation. At some point they will balance, and this is the dew point.

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