temp/rh relationship

[Schecter30]

The temp (74) was a little high in my humidor so I moved it too a cooler area of the house (reads about 71 now), but last time I checked the humidity went down from 68 to about 63. Is this due to the cooler temp? Should I keep the humidor here?

[Stonato~]

If I had to choose between your first set of numbers and the second, I'd go with the second. 63 is just fine especially if your temp is now cooler.

[wharfrathoss]

there's some globbityglookfleebleflobble scientific thing about relative humidity & the relation to temp-they have something to do w/each other, i'll leave it to the older, more intelligent members to explain-as far as should you keep it there, YES

[pinoyman]

If you're having trouble understanding "dew point" and "relative humidity," the text below should help you.

First, the warmer air is, the more water vapor it can "hold."
Dew point is a measure of how much water vapor is actually in the air.
Relative humidity is a measure of the amount of water in the air compared with the amount of water the air can hold at the temperature it happens to be when you measure it.
Amount of water vapor air can hold at various temperatures:

30 C: 30 grams per cubic meter of air

20 C: 17 grams per cubic meter of air

10 C: 9 grams per cubic meter of air

These numbers, which apply to air at sea level pressure, are based both on measurements over the years, and theory. They are basic physical facts.

Now, let's see how dew point and relative humidity work.

Imagine, that at 3 p.m. you measure the air's temperature at 30 degrees and you measure its humidity at 9 grams per cubic meter of air. What would happen if this air cooled to 10 degrees with no water vapor being added or taken away?

As it cools to 10 degrees the air becomes saturated; that is, it can't hold any more water vapor than 9 grams per cubic meter. Cool the air even a tiny bit more and its water vapor will begin condensing to form clouds, fog or dew - depending on whether the air is high above the ground, just above the ground, or right at the ground.

Back at 3 p.m., when we made the measurements, we could say that the air's dew point is 10 degrees C. That is, if this particular air were cooled to 10 degrees at ground level, its humidity would begin condensing to form dew.

How about relative humidity? At 3 p.m. the air has 9 grams of water vapor per cubic meter of air. We divide 9 by 30 and multiply by 100 to get a relative humidity of 30%

In other words, the air actually has 30% of the water vapor it could hold at its current temperature.

Cool the air to 20 degrees. Now we divide 9, the vapor actually in the air, by 17, the vapor it could hold at its new temperature, and multiply by 100 to get a relative humidity of 53% (rounded off).

Finally, when the air cools to 10 degrees, we divide 9 by 9 and multiply by 100 to get a relative humidity of 100% - the air now has all the vapor it can hold at its new temperature.

[Scimmia]

Everything that pinoyman is true, however, you're showing the opposite. This is most likely because the evaporation rate of water is directly effected by temperature, at a lower temperature, water is evaporating much more slowly than it was at the higher temperature. Give things a while to stabilize as the condensation and absorbtion rates are going to be a bit screwed up with the change in RH, too.

[chip]

Yer fine....don't overthink it.

[Tidefan73]

Originally Posted by chip

Yer fine....don't overthink it.

Don't fret the small stuff!! Just enjoy the smokes, they're fine...I think

[Stonato~]

Originally Posted by pinoyman

If you're having trouble understanding "dew point" and "relative humidity," the text below should help you.

First, the warmer air is, the more water vapor it can "hold."
Dew point is a measure of how much water vapor is actually in the air.
Relative humidity is a measure of the amount of water in the air compared with the amount of water the air can hold at the temperature it happens to be when you measure it.
Amount of water vapor air can hold at various temperatures:

30 C: 30 grams per cubic meter of air

20 C: 17 grams per cubic meter of air

10 C: 9 grams per cubic meter of air

These numbers, which apply to air at sea level pressure, are based both on measurements over the years, and theory. They are basic physical facts.

Now, let's see how dew point and relative humidity work.

Imagine, that at 3 p.m. you measure the air's temperature at 30 degrees and you measure its humidity at 9 grams per cubic meter of air. What would happen if this air cooled to 10 degrees with no water vapor being added or taken away?

As it cools to 10 degrees the air becomes saturated; that is, it can't hold any more water vapor than 9 grams per cubic meter. Cool the air even a tiny bit more and its water vapor will begin condensing to form clouds, fog or dew - depending on whether the air is high above the ground, just above the ground, or right at the ground.

Back at 3 p.m., when we made the measurements, we could say that the air's dew point is 10 degrees C. That is, if this particular air were cooled to 10 degrees at ground level, its humidity would begin condensing to form dew.

How about relative humidity? At 3 p.m. the air has 9 grams of water vapor per cubic meter of air. We divide 9 by 30 and multiply by 100 to get a relative humidity of 30%

In other words, the air actually has 30% of the water vapor it could hold at its current temperature.

Cool the air to 20 degrees. Now we divide 9, the vapor actually in the air, by 17, the vapor it could hold at its new temperature, and multiply by 100 to get a relative humidity of 53% (rounded off).

Finally, when the air cools to 10 degrees, we divide 9 by 9 and multiply by 100 to get a relative humidity of 100% - the air now has all the vapor it can hold at its new temperature.

ah damn, I got mine ALL wrong then. Better throw out all my humi's and start over!!!

[Deuce Da Masta]

Originally Posted by Stonato~

ah damn, I got mine ALL wrong then. Better throw out all my humi's and start over!!!

Um...do you need an address to toss those to? If so, I can 'recycle' that garbage for you.

[Stonato~]

Originally Posted by Deuce

Um...do you need an address to toss those to? If so, I can 'recycle' that garbage for you.

ok but I'm only tossing my Cubans... I don't think anybody cares for those.

[texasbadbob]

Rule #1 " only sweat the small stuff"
Rule #2 " it's all small stuff"