Particle Physics (40 of 41) What is a Photon? 24. Atmospheric CO2 Atmosphere

In this video I will discuss photon in relationship to CO2 atmospheric energy absorption.

Next video in the Particle Physics series can be seen at:

[alainclement]

Thank you Sir. I watched the whole series (1 to 41) and it was really the best physics class I ever had, my last one was in 1974 when I was 16, there were no quarks then. I'm sharing this lesson here with my friends on Facebook. I hope this will make them understand the situation better. No doubt there is a global warming, but let's find the proper culprit. My bet now is in a yet to be identified orbital cycle, or solar activity.

[TimDyck]

Do you have a transcript of this video? Your moving along fast and covering a lot and my brain cannot keep up. It's a good brain but I often need to read and reread things and ponder them befor it grabs the whole thing. Luckily once it does grab things it locks them in for life and I can move on to how the concept fits with other information I've learned and how it affects my concept of the universe and how it works.

[malclmjennings]

Thank you, Sir. for your videos. I have, by hand calculated the 15-micrometre wave band and came up with -80C then found the Wiens law calculator and came up with 79.97C.using the calculator I found 7micrometer 140C, 4 micrometres 451C. the H2O radiation window 8 micrometres 89C and 13 micrometres -50C.Sir the temperatures are so large like 451C for 4 micrometres this one I just cannot get my head around how duse 451C come about on earth please can you help

[andreialexandru]

7:25 Doubling the amount of CO2 in the atmosphere would warm up the atmosphere by how much? Where can I find more details on this matter?

[abcdef]

why does water absorb and increase the green house effect when water is totally transparent for the visible light range. water does not interact with sun light. but water absorbs infra red and ultra violet light heavily, so water is opaque for them.this explanation doesnt make sense.

[kimlibera]

I keep telling people this that they have to be specific IR photons, not just any.

[fractalnomics]

Personal notes: 1:42 back radiation claim  2:28 symmetric claim, "not very.." ; 4:05 claim if no GHGs ...average temp;

[Mikeisherest]

CO2's ECS of 0.3C to 0.4C per doubling is the lowest I've ever seen but then I haven't been keeping up. Any value under 1.0 and with no evidence of net WV amplification is basically the rug pulled out from under the CAGW movement.

[EliRabett]

At 5:30 the lecturer makes a common mistake assuming that that IR emission from the surface is simply absorbed and that there is no emission from greenhouse gases. That makes everything afterwards nonsense.


What happens is that after a greenhouse gas molecule is absorbed, the energy is degraded to thermal motion of nearby molecules by collisions within about 10 us. Some of the unexcited CO2 is also vibrationally excited by collisions, about 5% at 300K and atm pressure, less at lower pressure and temperature. About 1 in 100, 000 of those emits IR (in all directions). There are ~ 10^15 excited CO2 per cm^3 so that is still quite a lot. Since temperature decreases as you climb, the rate of emission decreases. Since density also decreases, the distance an emitted IR photon can travel before being reabsorbed increases, until that length is long enough that the photon can reach space.


If we increase the proportion of CO2 in the atmosphere, the altitude at which energy can be radiated to space rises, but since this higher level is colder and the pressure and density are lower, the rate at which IR can be emitted to space is lower and the surface has to warm more in order to shove the same amount of energy out and restore the balance with the incoming energy carried by sunlight.

[ericgrey]

This is excellent. I’d like them to also talk about collisions and also the fact that any re-radiated IR back to the surface will again radiate like a black body and hence will mainly go straight back through the atmospheric window.

[jakubkusmierczak]

Hello, Mr. Professor I have a question. How the frequency of the incoming light changes? It is claimed that green house effect is caused by lengthening the wave. The red shift is caused by strething the space-time architecture but here?
Thank You for the content. Best regards, follower.

[DoctorCoolu]

do greenhouse gases protect us from solar radiation that cause sunburns

[lengthmuldoon]

Superb presentation sir.

It does beg the question why the panic over co2 production when the influential bandwidths are essentially saturated????

[TomD-pfrn]

With respect to Michel's affiliations and potential conflict of interest, and in fairness to Michael maybe he doesn't know this, but his lectures are spread by members of the Heritage Institute, a fossil fuel-funded lobbyist group responsible for much of the climate change misinformation. It's pointed out by others that Michel uses incorrect figures in his calculations (CO2 bandwidth for example) . Hard to think this is an oversight considering he is obviously competent, but there's no evidence and I give him the benefit of the doubt. I would think he would comment or correct the video, especially if he knew that people are using this video to spread climate change misinformation.

[davewarkentien]

With much lower water vapor in the polar region, I would assume that CO2 has much higher affect on temperature than in other regions.

[petercamusojr]

I have a dumb questions. How does conduction heating verses EM absortion affect the co2 warming? I am assuming a specific heat of ~ 0.5. For that matter O2 and N2 and argon get warmed by the earth. Seems there should be a heat pipe cooling effect. I don't understand what happens to these molecules for energy storage and transfer.

[NicosM]

Most diagrams and public vulgarisations of the GHG effect promote the idea that the heating of the lower troposhere is due to IR photon being radiated back toward earth.

Their is never a clear distinction between the heating effect attributable to exited CO2 molecules delivering their energy locally  to other atmospheric molecules through collisions, and the heating effect attributable to energy being scaled back by CO2 molecules radiating toward earth.

Though it might be off topic here, adressing this question could be worth an other video ;)

[tyroneslothdrop]

What makes this video so shocking is that you don't appear to have a political agenda. I am not someone who believes in mass conspiracies, which is why I am confounded by this presentation.

[sueytonius]

Crap video with many errors. Van Biezen claims climate sensitivity is 0.3-0.4K. No, the best estimate is 2.5K.

There are far better, more reliable sources out there. Such is the case with YouTube videos.