> Secondly, think about this thought experiment: a layer of pure CO2 gas covers the lowest layer of air near the surface. By how much would that get warmer compared to air? The answer is there won't be any difference. That's because the surface and the air near it are at the same temperature, so they emit exactly the same amount of energy.
You've added an assumption in your question that the entire atmosphere is at the same temperature. This is trivially false; the atmosphere varies greatly in temperature. Some levels of the atmosphere can heat others, and indeed would do so more if those levels are composed of gasses which absorb more energy in the frequencies emitted, like CO2 does in practice.
> the absorption is possible only because the molecules have more degrees of freedom to vibrate.
The gases in the atmosphere are not blackbodies. They absorb different amounts of radiation at different frequencies because of those vibrational modes. If you substitute a gas in the atmosphere that absorbs no infrared with one that absorbs a lot of infrared, the atmosphere overall absorbs more energy and therefore warms.
> Except these models are dumpster fire. You can download some of them from NASA's website and judge the quality of code for yourself. Old fortran code, all the models copy code from each other,
The code quality has absolutely nothing to do with the predictive power of those models. Unless you have found bugs in the code, this is irrelevant.
> many things which aren't constant physically are constant in the code, functions full of tens of "if else" statements whose physical validity is highly in question.
Of course simplifying assumptions have been made. Can you point to an example of a variable made constant that you think is an oversimplification that would change the predictions so drastically as to remove warming from added CO2?
> There are also other glaring counter intuitive things about the narrative. Somehow CO2 effects continue to work slowly over decades, and the system doesn't reach an equilibrium with the current levels of CO2 until decades ahead.
I'm really not sure what you're trying to say here. It seems like you're implying that all thermodynamic changes to a system have to occur instantaneously. We may also not reach equilibrium for a very long time, if (as is very possible!) the warming of the Earth decreases its albedo.
> This is completely against normal thermodynamic intuition. Meta stable states exist, yes, and there are out of equilibrium systems. But usually the reason for systems not reaching the more stable state, is that their fluctuations are too small. In this case, the fluctuations are much much bigger than the supposed stable state change. We're talking about barely a degree change over decades in systems that fluctuate by several degrees daily. It makes no sense to claim their equilibrium will only be reached in decades while their fluctuation exceeds the difference to equilibrium daily.
I'm sorry, but your understanding of thermodynamics is extremely flawed. Metastable states have nothing to do with this. You are also making the basic error of confusing weather with climate here. The temperature increase that is discussed in climate science is an increase in the total energy of the atmosphere. By increasing the ability of the atmosphere to absorb energy, you increase its energy.
You are also arguing against models but have completely failed to address the fact that the atmosphere _is warming_. This is being measured and is no longer a hypothetical.
You skipped the part where I explicitly concluded that the effect comes from the difference in temperatures. I don't ignore it, I first understand the zero order - at uniform temperatures, there is no effect of CO2. Which leads to an understanding that if CO2 does indeed make a difference, it is the result of the temperature differences.
Then the part where I'm not at all certain about which direction the effect should be, is because while CO2 decreases thermal conductivity by radiation, it increases thermal conductivity by convection because the heat capacity is higher for CO2. Which is actually a much better intuition if you want to understand how does water vapor seems to have such negligible effect despite the fact it is a "greenhouse gas" and "absorbs much more heat".
You want me to point out bugs? There are like 20 different climate models. I've seen heat capacity being constant independent of pressure, temperature, CO2, density, etc. Not just heat capacity, but also other "constants". Not in a single place because the code is a mess, they actually have several different modules with different constants, so say the radiation simulation is extremely detailed mess that's completely unreadable, and the cloud simulation just starts all over with their own different constants.
Writing such code is somewhat human task, but reasoning about the magnitude of the mess that is going on there and which directions the errors will go is beyond the capabilities of anyone. It could be possible but not with the way it's currently written.
I'm sorry, but it is your thermodynamic intuition that's completely wrong. Equilibrium to you means "things stop moving". That... not how thermodynamics works at all. The reason that ordinary things look like they are "not moving" in equilibrium in your everyday life is because they do move, but at scales much smaller than you. Do the Brownian motion experiment.
And meta-stable states have everything to do with this, again this is your lack of understanding of physics, not mine. Given a thermodynamic system, there's expansion around the meta stable state or the unstable state over time, where you get the duration to reach equilibrium from the size of the fluctuations. The gist of the expansion is that what delays reaching equilibrium is that the fluctuations are too small.
There's infinite reasons why warming might be happening. Just the direction itself is a single bit of information with no significance whatsoever. It isn't worth my time arguing against a theory whose statistical strength is one bit.
The models don't have any significance beyond this bit or maybe two bits if you try to be generous about their abysmal performance regarding temperatures. They had some success at very high attitudes, but that's not surprising as these high attitudes are just so much simpler to predict and have no bearing on the rest of the model and the actual climate as observed on the ground. They excuse their shortcoming as the "weather", but if your models don't have any feedback from reality and testing around the parts that matter, why should I trust them ?
Have you considered that the Dunning–Kruger effect might be in play here? You're making lots of big claims and insisting everyone who disagrees with you doesn't understand physics. I have a degree in astrophysics and I've worked quite hard to get through thermodynamics courses. I'm quite confident that I do understand the thermodynamics involved here. Your argument seems to boil down to:
- The fact that you don't understand the mechanism through which CO2 would heat the atmosphere, and therefore you think it isn't happening.
- You reject every single climate model because of the simplifying assumptions and "bad code". Given that simplifying assumptions are necessary to do modeling and the amount of conspiratorial thinking in your other comments, I suspect that there aren't any assumptions you would agree with.
- You admit that warming is happening, but don't consider that to be evidence in favour of the models (even though they fit the data quite well). You claim they fit it poorly, well, let's see that study then!
> You skipped the part where I explicitly concluded that the effect comes from the difference in temperatures. I don't ignore it, I first understand the zero order - at uniform temperatures, there is no effect of CO2. Which leads to an understanding that if CO2 does indeed make a difference, it is the result of the temperature differences.
This is a vacuous statement.
> Then the part where I'm not at all certain about which direction the effect should be, is because while CO2 decreases thermal conductivity by radiation, it increases thermal conductivity by convection because the heat capacity is higher for CO2. Which is actually a much better intuition if you want to understand how does water vapor seems to have such negligible effect despite the fact it is a "greenhouse gas" and "absorbs much more heat".
Your lack of understanding is not a flaw in climate science.
> You want me to point out bugs? There are like 20 different climate models. I've seen heat capacity being constant independent of pressure, temperature, CO2, density, etc. Not just heat capacity, but also other "constants". Not in a single place because the code is a mess, they actually have several different modules with different constants, so say the radiation simulation is extremely detailed mess that's completely unreadable, and the cloud simulation just starts all over with their own different constants.
This is just you repeating what you said before. The code quality is not relevant unless you point out a bug.
> I'm sorry, but it is your thermodynamic intuition that's completely wrong. Equilibrium to you means "things stop moving". That... not how thermodynamics works at all. The reason that ordinary things look like they are "not moving" in equilibrium in your everyday life is because they do move, but at scales much smaller than you. Do the Brownian motion experiment.
I never made any such claim, nor did I imply that. Strawman argument.
> The models don't have any significance beyond this bit or maybe two bits if you try to be generous about their abysmal performance regarding temperatures.
What do you mean by this? Many of the models fit the warming in the recent past quite well. This process is called hindcasting.
Again I understand the mechanism, but I still claim it's not enough to wave your hands and tell the story, calculations matter, and in this case, the quality of calculations is extremely important. You are used to astrophysics where the standard is simply much higher, and you project that onto climate science.
There are no error boundaries or even attempt at giving meaningful estimation of the error in these calculations, in fact, the various models disagree quite wildly in the sense that after accounting for variation between models, you're left with barely a weak directional claim.
There's also a significance difference between predicting global climate, and estimating with accuracy the CO2 forcing. While the global temperature is at least measurable, nobody has any way to test CO2 forcing meaningfully. Which is the entire claim.
The reason for the decision to move trillions of dollars is the prediction about CO2 forcing, but if it is wrong and we're going to rely on "renewable energy" a.k.a. wind and sun when we are currently forecasting they are going to be unreliable, that's suicide. You can even worry about whether it is the correct decision even if the entire uncertainty was geopolitics by the way. In fact, just the unpredictability of China alone is enough to put the entire policy of the west in huge doubt, but that's something else.
> This is just you repeating what you said before. The code quality is not relevant unless you point out a bug.
I literally just pointed out several bugs. These things are not constant, they depend on these parameters, you're going to accumulate huge errors if you don't take them into account, and even worse, you're going to completely miscalculate CO2 forcing if you have entire sections of your code which ignore CO2 forcing (by having "constants" that aren't constants at all but depend on CO2).
And again, you're projecting from a real science (astrophysics) where you can point your telescope anywhere you wish and collect data, which is worth millions of bits, to climate science where the only "data" is very few temperature measurements which need to be averaged to retain a very weak signal.
But on the other hand, nobody dies because they got astrophysics wrong (except in "Don't look up" movie)
It's not science. They hardly have any data points fitting their models compared to the size of these models and the variation in their results, and most importantly, they don't have any data on the central claim (CO2 forcing) at all. My argument is basically, nobody can trust the story because stories are misleading, you need a detailed calculation. Not misleading in a conspiratorial way, misleading in that this is numerical question which we humans suck at estimating narratively.
And again, those calculations could and should be much less of a dumpster fire if we're going to trust the future of humanity with them. Another example of "simplifying assumptions" blowing up in the face of the economy was 1987 stock crash where "simplifying assumptions" in modelling option prices blew up in everyone's faces and led to multi year recession. And another "simplifying assumption" in the coronavirus response led by misleading infection models and proceeding ahead out of pure cognitive dissonance. I'm sure the climate modelers are doing the best they can, but the best they can is not enough.
This dishonesty about the certainty of models, which usually results from a broken telephone where the honestly and articulated science claims are transformed into propaganda that misleads even the leaders is a bigger problem than what these models claim to solve.
If this blows in everyone's faces and "moving to renewables" turns out to be a complete disaster, they will be hanging scientists in the streets and I won't blame them. Everyone's maximizing for the "scientists were extremely accurate in their predictions and we listened to them and got it right" scenario and it's because in everyone's mind the probability the scientists are right is like 90% when in reality it's more likely 10%.
I don't want to convince you it's wrong. I want to convince you it's very non-trivial calculation to understand whether the problem is CO2, that framing it as "scientists always knew that and it's basic physics" is extremely misleading about the certainty, and that the narrativistic mindset is extremely dangerous.
You've added an assumption in your question that the entire atmosphere is at the same temperature. This is trivially false; the atmosphere varies greatly in temperature. Some levels of the atmosphere can heat others, and indeed would do so more if those levels are composed of gasses which absorb more energy in the frequencies emitted, like CO2 does in practice.
> the absorption is possible only because the molecules have more degrees of freedom to vibrate.
The gases in the atmosphere are not blackbodies. They absorb different amounts of radiation at different frequencies because of those vibrational modes. If you substitute a gas in the atmosphere that absorbs no infrared with one that absorbs a lot of infrared, the atmosphere overall absorbs more energy and therefore warms.
> Except these models are dumpster fire. You can download some of them from NASA's website and judge the quality of code for yourself. Old fortran code, all the models copy code from each other,
The code quality has absolutely nothing to do with the predictive power of those models. Unless you have found bugs in the code, this is irrelevant.
> many things which aren't constant physically are constant in the code, functions full of tens of "if else" statements whose physical validity is highly in question.
Of course simplifying assumptions have been made. Can you point to an example of a variable made constant that you think is an oversimplification that would change the predictions so drastically as to remove warming from added CO2?
> There are also other glaring counter intuitive things about the narrative. Somehow CO2 effects continue to work slowly over decades, and the system doesn't reach an equilibrium with the current levels of CO2 until decades ahead.
I'm really not sure what you're trying to say here. It seems like you're implying that all thermodynamic changes to a system have to occur instantaneously. We may also not reach equilibrium for a very long time, if (as is very possible!) the warming of the Earth decreases its albedo.
> This is completely against normal thermodynamic intuition. Meta stable states exist, yes, and there are out of equilibrium systems. But usually the reason for systems not reaching the more stable state, is that their fluctuations are too small. In this case, the fluctuations are much much bigger than the supposed stable state change. We're talking about barely a degree change over decades in systems that fluctuate by several degrees daily. It makes no sense to claim their equilibrium will only be reached in decades while their fluctuation exceeds the difference to equilibrium daily.
I'm sorry, but your understanding of thermodynamics is extremely flawed. Metastable states have nothing to do with this. You are also making the basic error of confusing weather with climate here. The temperature increase that is discussed in climate science is an increase in the total energy of the atmosphere. By increasing the ability of the atmosphere to absorb energy, you increase its energy.
You are also arguing against models but have completely failed to address the fact that the atmosphere _is warming_. This is being measured and is no longer a hypothetical.