Effective Emission Height Calculation?

In summary, the NASA article discusses how water vapor amplifies the Earth's greenhouse effect. The article provides equations for calculating the effective emission height, which is a real thing. The article also discusses how the effective emission height and average height of emission are similar concepts.
  • #1
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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  • #4
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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  • #5
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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  • #6
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
 
  • #7
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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  • #8
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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FAQ: Effective Emission Height Calculation?

What is Effective Emission Height?

Effective Emission Height (EEH) is the altitude in the atmosphere from which the majority of a certain type of radiation, such as infrared radiation, is emitted. It is a crucial parameter in atmospheric science and climatology for understanding and modeling the Earth's energy balance and greenhouse effect.

Why is Effective Emission Height important?

EEH is important because it helps scientists determine the temperature at which the Earth radiates energy back into space. This, in turn, affects the Earth’s energy balance and climate. Understanding EEH is essential for accurate climate modeling and predicting future climate change scenarios.

How is Effective Emission Height calculated?

EEH is calculated using radiative transfer models that take into account the absorption and emission of radiation by different atmospheric gases at various altitudes. These models use data from satellite observations and ground-based measurements to estimate the height at which the atmosphere becomes transparent enough for radiation to escape into space.

What factors influence Effective Emission Height?

Several factors influence EEH, including the concentration of greenhouse gases, atmospheric temperature profiles, humidity levels, and cloud cover. Changes in any of these factors can alter the altitude at which radiation is most effectively emitted.

How does Effective Emission Height vary with different greenhouse gases?

Different greenhouse gases have different absorption and emission characteristics, which means they have different EEHs. For example, carbon dioxide (CO2) and water vapor (H2O) have different absorption spectra, leading to different EEHs. Generally, gases with stronger absorption bands in the infrared spectrum will have higher EEHs.

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