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Comment by Leftium | Hacker News Reader

The Wet Bulb temperature still needs a unit of measurement.

> Even heat-adapted people cannot carry out normal outdoor activities past a wet-bulb temperature of 32 °C (90 °F), equivalent to a heat index of 55 °C (130 °F)

So the F wet bulb temperature seems to make even better use of 2 digit readings than "plain" F. With 2 digits, C only uses 32% of the possible 2-digit readings.

I couldn't find anything for the low end...

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The Wet Bulb temp can use any scale they see fit, it's a derived unit. It's even better if they don't use F and C to avoid confusion.

> The wet-bulb temperature (WBT) is the temperature read by a thermometer covered in water-soaked cloth (wet-bulb thermometer) over which air is passed

It seems to be a direct measurement, not derived from anything. You might be able to derive WBT given the dew point and dry bulb temperature, but it would still need units like C or F.

Perhaps you were thinking of a different measurement?

I believe that's a shortcut to measure WBT directly. By it's nature, WBT are affected by other variables such as humidity and atm pressure, etc... , so it's a derived unit: Twb = F(T, H, P...). As a derived function, you tweak its scale as much as you like, you can take T = C*2 and that solved your problem.

But surely deriving the WBT couldn't change the unit of measurement?

A measurement that has no unit is relative humidity. It is just a percentage. There is no way to measure relative humidity directly and get any other type of unit besides a percentage. Instruments that measure relative humidity directly measure in percentages.

edit: ah, you can use C2 = Celsius*2 whether you're talking about regular temperature or WBT. C2 is the 'derived' unit. Not WBT.

Yes you can use C2, but why not just use F which still has better precision than C2[1]? For low values of C2, you may confuse it with plain C...

[1]: https://uxdesign.cc/celsius-needs-a-redesign-41709e048c4a

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