Effective Emission Height Calculation?

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    Atmosphere Cooling
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Discussion Overview

The discussion centers around the calculation of Effective Emission Height (EEH) in the context of climate change, specifically relating to the role of water vapor and its interaction with carbon dioxide in the atmosphere. Participants explore mathematical modeling and seek clarification on the scientific equations that underpin these concepts.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant notes that as a gas becomes denser, the height at which it emits infrared radiation increases, leading to reduced cooling and more heat retention, particularly in relation to CO2 levels.
  • Another participant expresses a desire to develop their own equation for EEH and emphasizes the importance of discussing parameters related to humidity as a cooling agent in the atmosphere.
  • A participant mentions that the EEH for Outgoing Longwave Radiation is approximately 5 km above the surface and seeks to understand the equations related to the impact of humidity on greenhouse effects.
  • There is a request for references to peer-reviewed literature to support claims and calculations, highlighting the forum's rules regarding discussions on climate change.
  • One participant questions the scientific basis behind the assertion that increased humidity doubles the warming effect of CO2 and seeks the mathematical equations that explain this relationship.
  • Another participant shares a reference to a scientific paper that may provide relevant insights into the modeling of atmospheric processes.

Areas of Agreement / Disagreement

Participants express a shared interest in the scientific and mathematical aspects of EEH and its relation to climate change, but there is no consensus on the specific equations or models to be used. The discussion remains unresolved regarding the exact calculations and references needed.

Contextual Notes

Participants acknowledge the complexity of the calculations involved in determining EEH and the role of humidity, with some expressing frustration over the difficulty in locating definitive equations. The discussion is framed within the context of established scientific literature and the forum's guidelines on climate change discourse.

PeterG
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This is a climate change calculation question.

AGW (Anthropocentric Global Warming) theory states that as a gas gets more dense, the height at which it will release IR (Infrared Radiation) to outer space gets higher.
Higher in the Atmosphere is cooler.
Cooler means a lower IR output.
Reduced cooling means more heat retention.
So a doubling of the CO2 in the atmosphere causes a reduction in heat output to outer space, effectively warming the earth's surface.

Using this information, has anyone come across any mathematical modelling of this process?

I am looking to apply this theory to the Water Vapour / Humidity part of the atmosphere.
 
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Thankyou Bystander
I might need to build an equation myself then post it here to give folk a clearer fee for what I am trying to calculate, and help requested?
The best Google search term to use is probably "Effective Emission Height" (EEH).
For OLR (Outgoing Longwave Radiation) from the Earth to Outer Space the EEH this value is approximately 5km above the surface.
The EEH and Average Height of Emission are quite similar concepts.

I was hoping it might be fun to chat about the various parameters in a forum like this if folk were interested.
I am specifically interested in pinning some numbers to the "humidity" or "H2O" element of atmospheric gas since this is the main atmospheric coolant.
Here is an excellent site discussing the science, equations and numbers around this topic which might stimulate some thoughts.
[Reference redacted by the Mentors]
 
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PeterG said:
I might need to build an equation myself then post it here to give folk a clearer fee for what I am trying to calculate, and help requested?
The Global Warming discussion rules for PF stipulate that discussions must be based on the published peer-reviewed literature. So if you can find some of the equations you are seeking in that literature, please post links to those articles and you can ask questions about them. We're not the right place to be trying to develop your own equations.

More about the GW/CC rules can be found here: https://www.physicsforums.com/threads/climate-change-global-warming-policy.757267/

Thank you.
 
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Thankyou

And I appreciate the reason for this.
There are many destructive conversations about climate change which have little to do with science.
My question is really one about clarification?
I want to locate science and equations?

Is a NASA website ok for reference?
https://climate.nasa.gov/explore/as...ater-vapor-amplifies-earths-greenhouse-effect
I simply want to find the equations behind this line -
"Scientists estimate this effect [increased humidity] more than doubles the warming that would happen due to increasing carbon dioxide alone."
Is it reasonable to wonder what the actual equations and science are behind this line?
I have posted this question on the NASA Facebook page but not had a response just yet so thought to ask elsewhere?

So the question is mathematically - how does H2O double the effect of CO2?
In strict mathematical numerical scientific terms?

This mechanism for CO2 is valid.
The EEH is a real thing.
It is a complicated, yet not impossible calculation.
For the whole of the atmosphere in general the EEH is about 5km you can google it.
Some of those EEH judgements use a proxy value, temperature, to locate EEH which seems a rather woolly shortcut and unsatisfactory way to do things, not particulary scientifically-mathematically minded?
I want to find the hard equations behind this?

Is that a fair or reasonable question to pose here?

I appreciate Climate Change is a hot topic, and I appreciate why there are these rules.
If not, that's fine, I appreciate the forum rules are to prevent bad tempered conversations which go around in circles and get nowhere?
But I find this really interesting from a thermodynamic and mechanical Physics point of view and am surprised to be having difficulty locating the equations behind the NASA information?

Thankyou !
 
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PeterG said:
But I find this really interesting from a thermodynamic and mechanical Physics point of view and am surprised to be having difficulty locating the equations behind the NASA information?
+1
 
Owens, A.J., Hales, C.H., Filkin, D.L., Miller, C., Steed, J.M., and Jesson, J.P., A Coupled One-Dimensional Radiative-Convective, Chemistry-Transport Model of the Atmosphere, 1. Model Structure and Steady State Perturbation Calculations, J. Geophys. Res., 90, D1, 2283-2311, (1985)
 
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Chestermiller said:
Owens, A.J., Hales, C.H., Filkin, D.L., Miller, C., Steed, J.M., and Jesson, J.P., A Coupled One-Dimensional Radiative-Convective, Chemistry-Transport Model of the Atmosphere, 1. Model Structure and Steady State Perturbation Calculations, J. Geophys. Res., 90, D1, 2283-2311, (1985)
Thankyou

That does look very interesting.
Take me a moment to access the whole report and take it in.

Thankyou
 
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