Heat?

[Goose52]

Something has been kicking around in my head. Now I have been told the only stupid question is the one that is unasked so here goes. We have all read copious amounts about CO2. How it gets into the system. How long it stays in the system. What it does or does not do in the system. How much goes where in the system.

It seems to me that is only half of what we need to understand. What about the other half? Heat. Can anyone answer or point me toward reading that answers all of the same questions. We all know how heat gets into the system. The sun. How long does heat stay in the system? What does heat do in our system? We are told by some that CO2 can last up to 100 years in the system. Does the absorbed heat stay with that molecule for 100 years? If not where does it go and how? Heat!!! I want to learn about heat.

[Richard111]

Good question. I've been trying to pin that down for nearly a year now.

Have a read of George E. Smith's comments at WUWT:

http://wattsupwiththat.com/2008/11/25/ad.../#comments

Quote:George E. Smith (11:40:11) :

One can model the optical transmission of absorptive of materials as a logarithmic function. If a certain thickness transmits 10% of a given spectrum, twice the thickness will transmit 1%, and so on; BUT such materials absorb the radiation and convert it entirely to thermal energy.

Not so with water vapor or CO2 or any other GHG. Some absorption processes may convert some of the energy to heat energy; but mostly the absorbed IR photon is simply re-emitted, perhaps with a frequency shift due to Doppler effects, or even Heisenberg uncertainty. Subsequent re-absorption by other GHG molecules, may face totally diffrent results due to temperature and pressure changes in between successive absorption-re-emission events. The likelihood that such processes follow any simple logarithmic function is rather remote, and the possibility that the global mean surface temperature change due to such porocesses also follows a logarithmic function; even more so.

I know all the books and papers say it’s logarithmic; how many of them derive the specific logarithmic function based on the molecular spectroscopy physics ?

Once the page has loaded do a ctrl-f (find) and type in George E. This will take you to all his posts in turn.

But you won't find the answer to your question.

Have a read of these two pages which are pdf's which are text only and give you links to lots of science essays, all in text pdf form, which will give you a good grasp of the science.

http://www.climates.com/KA/H2OMENU.pdf

http://www.climates.com/SPECIAL%20TOPICS...arming.htm

In my naive way I assumed if I could calculate the total mass of the GHG molecules in a given volume of the atmosphere and knowing the level of OLR from any surface I should be able to calculate the amount of heat passed into that block of air. No luck so far.

It seems a photon of IR leaving the surface has a lifetime measured in micro-seconds. As George points out above very little radiation is converted to heat energy. (But how much????) Most is re-radiated.

This brings me to a new line of enquiry, the optical depth of the atmosphere. I am not any sort of a scientist so anything I say is my personal opinion. But intuitively I suspect there will be a different optical depth for all the different bands of radiation that take part in the GHE. Limiting the discussion to CO2 we are told that wavelengths of 2.7, 4.3 and 15 micrometers (µm) are the spectra for CO2. Lumped together they constitute something less than 8% of the total available energy. LINK
These are the centre wavelengths of "bands", i.e. 13-18 microns depending on temperature and pressure.

For any optical depth ALL available radiation is absorbed and something less that half is radiated back to the surface and the equivalent carries on up through the atmosphere. The next optical layer above is now getting less than half of what it is capable of absorbing, (less than 4%) but this doesn't mean that this layer will radiate any less energy. The GH gasses in that layer will still radiate according to their ambient temperature. Therefore GHG's above their respective atmospheric optical depths have a cooling effect. There are lots of reports out there that the upper troposphere is cooling despite all the claims in the IPCC report of the "upper tropospheric hotspot".

Makes you think.

[HarpoSpoke]

(11-30-2009 10:27 PM)Goose52 Wrote:  How long it stays in the system.
(snip)
We are told by some that CO2 can last up to 100 years in the system. Does the absorbed heat stay with that molecule for 100 years?

From what I understand, most research on that question indicates CO2 residence time is 10 years or less (much less in many studies).

It's only recently that the idea of residence time started growing to "50 years", "100 years", and longer.

[Sunsettommy]

Try this:

Greenhouse Gas Facts and Fantasies

and,

Carbon cycle modelling and
the residence time of natural and
anthropogenic atmospheric CO2:
on the construction of the
"Greenhouse Effect Global Warming" dogma.

[Goose52]

Richard the second link you provided was an excellent read. From my observations I would think heat spends much less time in the system as compared to CO2. If you consider the global system and compare it to say your house. Today it is cold in Colorado. Very cold. For the Earth its furnace is the Sun. For my model, my house, the Sun is represented by my York furnace. If I were to turn off my furnace just how long would it take for the heat to escape the system? Not very long at all. Just how much heat would CO2 absorb and keep in the system of my house after my York furnace is shut off? I think the same observation applies with the larger system.

[Sunsettommy]

(12-09-2009 10:53 PM)Goose52 Wrote:  Richard the second link you provided was an excellent read. From my observations I would think heat spends much less time in the system as compared to CO2. If you consider the global system and compare it to say your house. Today it is cold in Colorado. Very cold. For the Earth its furnace is the Sun. For my model, my house, the Sun is represented by my York furnace. If I were to turn off my furnace just how long would it take for the heat to escape the system? Not very long at all. Just how much heat would CO2 absorb and keep in the system of my house after my York furnace is shut off? I think the same observation applies with the larger system.

Sure you can turn off the sun,but the "heat" transfers away from the surface continues until there is none left.