How does Carbon Dioxide increase global temperatures?

[Temp]

Just had similar answer from a son.

 

Some absorption lines depend the "electronic" structure and others the "molecular" structure of the gas. The electronic structure is all about electron orbitals (the "fixed" gaps between orbitals leads to absorption lines having fixed wavelengths). The molecular structure is its vibrational and rotational properties/modes. 

 

This video covers lines caused by the electronic structure..

 

 

[Temp]

7 hours ago, SteamyTea said:

For that matter, why should snow, which is cold, and made from water, reflect UV and not absorb IR.

 

I don't know if that's correct but..

 

If the wavelength depends on the molecular/mechanical properties it shouldnt be surprising that that water and ice have different lines because they have different mechanical properties.

 

https://en.m.wikipedia.org/wiki/Absorption_spectroscopy

 

The frequencies where absorption lines occur, as well as their relative intensities, primarily depend on the electronic and molecular structure of the sample. The frequencies will also depend on the interactions between molecules in the sample, the crystal structure in solids, and on several environmental factors (e.g., temperature, pressure, electromagnetic field).

 

 

[SteamyTea]

@A_L

Brilliant. I think I can build a story around that.

Thank you.

[epsilonGreedy]

On 02/01/2020 at 13:02, Ed Davies said:

Professor Mike Merrifield is probably better at explaining this than, particularly with the advantage of animations and gestures.

 

 

His video is very well presented though falls way short of strong support for global warming concern as he is describing an isolated mechanism. If I had 30 minutes of 1-on-1 Q&A time with prof Mike I would ask:

 

"Given your concern about run-away warming feedback mechanisms what climatic limiter kicks in to prevent run-away warming at the end of each ice-age?"

 

Background: It is generally accepted that solar orbital variations trigger the end of each ice-age but such solar variation is insufficient to explain the dramatic rise in temperature to an initial high spike that is warmer than the inter glacial average. CO2 release from warming oceans is the prevailing explanation for the initial run-away warming that leads into an inter glacial period, so what mechanism caps the initial temperature spike? 

[epsilonGreedy]

On 02/01/2020 at 13:12, Ed Davies said:

[earth's orbit]

 

nope, it's the same distance as always, on average.

 

 

I know you are smart enough to identify the self contradictory absurdity in that statement above.

 

Experts on all points of the alarmist/skeptic spectrum accept the profound significance of the various Milankovitch cycles and apparently so do you because in order to counter my point the earth's climate being scheduled to descend into the next ice-age you claim it will be different this time because:

 

On 02/01/2020 at 13:12, Ed Davies said:

It's controversial whether or not the next dip in the Milankovitch cycles would cause an ice age. The consensus now is that they won't for quite a while: https://en.wikipedia.org/wiki/Milankovitch_cycles#Present_and_future_conditions “Earth's orbit will become less eccentric for about the next 100,000 years, so changes in this insolation will be dominated by changes in obliquity, and should not decline enough to permit a new glacial period in the next 50,000 years.”

 

 

p.s. While following up your link re. the next ice-age being postponed by 50,000 years I found some choice quotes that reinforce my position:

 

https://pdfs.semanticscholar.org/c3ae/7330dbbad1522d6a5f254f181eb4c9483b9b.pdf?_ga=2.225785561.23546783.1578483428-2001527689.1578483428

 

Quote

On a geological time scale, climate cycles are believed to be driven by changes in insolation (solar radiation received at the top of the atmosphere) as a result of variations in Earth’s orbit around the Sun.

 

Quote

For example, according to Saltzman et al. (11) an increase in atmospheric CO2, if maintained over a long period of time, could trigger the climatic system into a stable regime with small ice sheets, if any, in the Northern Hemisphere. Loutre (12) also showed that a CO2 concentration of 710 ppmv, returning to a present-day value within 5000 years, could lead to a collapse of the Greenland Ice Sheet in a few thousand years.

 

 

And before climate change hysteria corrupted scientific process in 1972 it was thought...

 

Quote

Assuming a similar duration for all interglacials, the scientists concluded that “it is likely that the present-day warm epoch will terminate relatively soon if man does not intervene”

 

[SteamyTea]

@epsilonGreedy

Does that video explain, in simple terms, what the mechanism is that causes complex gas molecules to trap radiation.

If not, it is just not answering the question I asked.

Edited January 8, 2020 by SteamyTea

[epsilonGreedy]

1 minute ago, SteamyTea said:

@epsilonGreedy

Does that video explain, n simple terms what the mechanism is that causes complex gas molecules to trap radiation.

If not, it is just not answering the question I asked.

 

 

No it just explains how greenhouse gases affect the atmosphere and ground temperatures. The video assumes such gases "trap radiation".

 

I have viewed an extremely deep sub atomic explanation of how gases trap and emit energy, 90% of the video entered my brain and then exited without useful knowledge capture.

 

I dare not post a link here out of fear it would trigger a destructive run-away process in @Ed Davies's brain because the presentation is by Professor William Happer of Princeton University who was also appointed as chief scientific adviser to President Trump. ?

[Ed Davies]

1 hour ago, epsilonGreedy said:

His video is very well presented though falls way short of strong support for global warming concern as he is describing an isolated mechanism.

 

Indeed, it just describes the mechanism. Let's remember what the discussion here is about: @SteamyTea's original question was about the mechanism by which certain trace gasses in the atmosphere “trap” heat and how to convince somebody that they can have an effect. As I see it, there are two parts to this question: a) what's happening on the atomic and molecular scale as photons of various wavelengths get absorbed and emitted and b) the slightly wider issue of whether there's enough gasses present to have much effect.

 

@SteamyTea is more interested in a). I'm willing to take hand-wavy explanations about molecular bonds and molecules with three or more atoms, etc, on trust because I know there's a vast amount of physics which has been done around this subject going back nearly 200 years and that if climate scientists were getting things wrong in this area there'd be a huge number of other physicists, astronomers, engineers and so on telling us all so. As far as I know nobody with even a smidgen of credibility has raised any serious doubts in this area.

 

I'm more interested in b) as it's something somebody could reasonably have some doubts about until shown some simple facts about how much of these “trace” gasses are actually present.

[SteamyTea]

26 minutes ago, Ed Davies said:

As I see it, there are two parts to this question: a) what's happening on the atomic and molecular scale as photons of various wavelengths get absorbed and emitted and b) the slightly wider issue of whether there's enough gasses present to have much effect.

Yes, I am interested in the first bit here, then when that is sorted, maybe the second bit.

I think I may call up someone I know at a university and ask if they know the answer.  Though when I asked her 15 years ago, she waved her hands and said 'I hate degrees of freedom'.

 

ps I have just left the clever chemist a message, see if she gets back to me.

Edited January 8, 2020 by SteamyTea

[SteamyTea]

Just finished my meeting with the clever chemist.

All about dipoles  and negativity.

Seems that when a molecule absorb energy, at the right levels, it changes shape.

This makes it vibrate and rotate differently. After a short time, it slows and spits out a photon at different (lower) energy level.

So CO2 (shall make the 2 subscript later) starts off as a non polar molecule until some energy heats it up, then it bends, this upsets the electrical balance. It is now a polar molecule. After a short time, it straightens, losing the energy it has gained.

So I am thinking it is a bit like a bi-metalic strip. Starts straight, heat if and it bends, as it coils it straightens again.

 

That is as far as I have got.

 

[epsilonGreedy]

51 minutes ago, SteamyTea said:

So I am thinking it is a bit like a bi-metalic strip. Starts straight, heat if and it bends, as it coils it straightens again.

 

 

Professor William Happer used a foam tube about 4ft long in his co2 YouTube video and flapped the ends from the centre to mimic resonance and vibration, then he started spinning himself around to indicate co2 molecular spin.