Author Topic: Bulb Temperature  (Read 3043 times)


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Bulb Temperature
« on: October 25, 2010, 03:01:57 pm »
Well I've been entering weather readings for a few days now, but I really like to know what it is that I'm doing so can someone clarify what the bulb temperature is and how its different from air temperature?

At the moment I'm assuming that it's a wet and dry bulb thermometer and therefore it's a measure of humidity. If that's the case then the bulb temperature should never be higher than the air temperature (usually the case) and the greater the difference then the lower the relative humidity.


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Re: Bulb Temperature
« Reply #1 on: October 25, 2010, 07:14:13 pm »

There's a page about the instruments and their use in WW1 warships at

Hope this helps.


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Re: Bulb Temperature
« Reply #2 on: October 26, 2010, 06:18:14 pm »
Hi Oddstacks.

 All your assumptions are correct. It is a wet-bulb temperature, from which we infer the humidity, and it should never be higher than the dry-bulb temperature (that is, the air temperature in the previous column). Comparing wet and dry-bulb temperatures is one of the checks we do on the observations to make sure they are sensible before using them.