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[This post is marked as unsolved] What is the calculation for absoulute humidity?  

Trusted Member

Hi Chris,

let me describe what i want to do:

I have a cellar with 80% relative humidity and a stable temperature of 12°C.

Outside if have 86% relative humidity and -2°C.

Using my formula i get for:

cellar: 80% / 12° -> 8,3 g/m³

outside: 86% / -2° -> 3,6 g/m³

This means the relaitive humidity is higher outside BUT the absolut humidity is much smaller.

So i makes sense to open the window and make an air exchange to remove the wet air from my cellar.

I used this online tool to calculate the absolute humity above and the tool is using this formula.

Perhaps the result of the formula is not 100% correct but it points me to open the window or not.

Now my idea is to manually put this formula in wetherstation to see th complete process a  line graphic.

best regards


This post was modified 6 months ago by SetMin
Posted : 25/01/2019 2:31 pm
Pierre Lannoy
Member Admin

If it's only to compare several absolute humidity values, you don't care about units as long as they are the same  😋 

If you like Weather Station, please consider to make a review to help make it known. That would be the best way to thank me...

Posted : 25/01/2019 3:44 pm
SetMin liked
Reputable Member 🇩🇪🇨🇭Editor

Exactly what I wanted to say, you can simply compare the values in g/kg in your case 😉 

And in terms of meteorology (which, after all, is what this plugin in is mainly about) it does not make sence to use g/m³ when comparing humidities.

This post was modified 6 months ago by Chris

I like the cold weather. It means you get work done.

Posted : 25/01/2019 4:06 pm


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