My question was rather simple:

The forcing from methane is dependent of other gasses in a complicated formula.so i wonder if the CO2 forcing really is independent of even the most powerfull GHG, water vapor?

How could it be that the forcing from changing CO2 content 5.35ln(C/Co) is independent of the other green house gasses especially H2O.

I find it strange that this very simple forcing formula is completely independent of

other GHG gasses that share the same radiation bands.

If the answer is that it is so, i would like a little explanation of how that could be.

If the answer is that it is dependent i would like a better formula.

I know it is very complicated because water vapor vary a lot with hight, but anyway some approximations would do.

I am not born and raised with english. Concider that if you find my wording a little strange.

]]>For example, by changing the water vapor scale from 1.00 to 1.01, I think you are modeling a 1% increase water vapor at all altitudes as a forcing. If you use a temperature offset of 1 K, you can compare constant absolute humidity to constant relative humidity. The difference appears to be water vapor feedback.

For clear skies, OLR is presumably calculated by integrating the Schwarzschild equation from the surface (at surface temperature, ? emissivity) to the TOA. For cloudy skies, OLR is calculated starting from the cloud top (temperature determined by lapse rate?) and integrating to space. MODTRAN offers a variety of cloud options. If you “look down” through clear skies from 2 km, you can compare OLR at 2 km to a hypothetical cloud emitting blackbody radiation upward from that altitude.

]]>It’s a complex and technical subject.

There’s some terminology that’s important.

“Forcing” = (in simple terms) change in the radiative balance of the planet as a result of changes in GHGs, like CO2.

“Feedback” = the resulting changes following radiative forcing, for example, the changes in water vapor and clouds and how they affect the climate.

So changes in CO2 are a forcing and the resulting changes in water vapor and clouds are a feedback.

But what you ask – as I read it – might not be what you mean to ask.

Depending on your appetite for learning about the important concepts, you might find these articles helpful:

Wonderland, Radiative Forcing and the Rate of Inflation

Wonderland and Radiative Forcing – Part Two

You might really be asking about whether water vapor overwhelms the CO2 effect?

Visualizing Atmospheric Radiation – Part Four – Water Vapor

– it might be best to start at the beginning of that series to get familiar with the concepts.

]]>The forcing from methane is dependent of other gasses in a complicated formula.so i wonder if the CO2 forcing really is independent of even the most powerfull GHG, water vapor?

A connected side question: Is the CO2 forcing dependent of the cloud cover?

Please state the assumptions you have to make to answer this rather complicated questions.

I have tried to find answers, but have failed so far. Hope You can help.

]]>Anyone interested in RW’s wisdom – search for “RW” in the search bar. Thousands of comments to review.

I don’t believe RW has anything new to add so unfortunately I will be deleting new comments from this esteemed commenter. On the positive side he has a large volume of extant work preserved here for interested parties.

]]>The IPCC’s 70% confidence interval for ECS ranges from 1.5-4.5 K, so they take 3.4 K with a mountain, not a grain, of salt. In fact, AR5 deliberate chose not to provide any “best estimate” for ECS, just a likely range. However, few of the IPCC’s models sample ECS below 2.5 K and none below 2.0 K, so their projections are misleading since aren’t based on their confidence interval.

There are plenty of reasons to be disdainful of AOGCM output, but not the work of those who attempt to illuminate climate sensitivity with observations. like those you mentioned above.

At the link below, I derived the following expression for the planet’s climate feedback parameter (dRi/dT):

dRi/dT = -4eoT^3 – oT^4*(de/dT) – S*(da/dT)

Planck feedback + other LWR feedbacks + SWR feedbacks

CERES has been observing 3.5 K of seasonal warming for more than a decade. It tells us that Planck feedback and other LWR feedbacks total -2.2 W/m2/K, meaning that the IPCC gets positive feedback from WV+LR about right, but their LWR cloud feedback is too positive.

There isn’t much seasonal warming in the tropics, so -2.2 W/m2/K may not be appropriate for the tropics. Lindzen looked at the tropics and came up with an LWR feedback of -5.3 W/m2/K. And Mauritsen and Stevens (2015), two supporters of the consensus, obtained an LWR feedback of -4 W/m2/K (confirming Lindzen’s conclusion about negative overall LWR feedback in the tropics). They modified a model to cause storms to cluster as seen in cloud resolving models (a type of IRIS effect) and obtained positive LWR feedback!

http://eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf

https://www.researchgate.net/profile/Thorsten_Mauritsen/publication/275268225_Missing_IRIS_effect_as_a_possible_cause_of_muted_hydrological_change_and_high_climate_sensitivity_in_models

So we no longer need to rely on the IPCCs climate models to have a reasonable idea of what LWR feedback is. We have observations.

The data doesn’t show a linear relationship between Ts and reflected SWR. LC11 found SWR feedback of -1.9+/-2.6 W/m2/K with a three-month lag (R^2 = 25%) and by my eye +3 W/m2/K with zero lag and similar R^2. I personally don’t see any reason to call any of these poorly-linear relationships “SWR feedback”. (For the LWR response, R^2 is about 60%.in the tropics and much higher for seasonal warming.)

There is a simple way to put some sort of limit on SWR feedback. Our planet reflects 100 W/m2 of SWR back to space. If that reflection changes +/-1%/K, that is +/-1 W/m2/K in SWR feedback. Given that the planet was 6K cooler at the LGM, +/-1 W/m2/K is a pretty big change. So I’m personally betting SWR feedback will be somewhere between +1 and -1 W/m2/K. Which puts overall ECS in the vicinity of EBMs.

RW, before you indiscriminately defecate on work you don’t understand, consider asking a narrowly focused question. Some climate scientists actually do real science: They start with observations.

]]>“Yes, but it’s the 1.2C claimed measure of theoretical intrinsic effect via the GHE which isn’t supported by the theory (and which is my whole point). It’s an amount that will restore balance — yes, but it’s arbitrarily used more or less because the field doesn’t have a valid model or a way to quantify the theoretically supportable intrinsic effect from 2xCO2.”

This is unambiguously wrong. Given that the Schwarzschild equation predicts that the enhanced GHG from 2XCO2 will reduce radiative cooling to space by roughly 3.6 W/m2, the question we are faced with is simply: How much does the planet need to warm to emit an additional 3.6 W/m2 and restore a steady state between incoming and outgoing radiation? In other words, what is the planet’s climate feedback parameter in W/m2 emitted per degK of surface warming? (W/m2/K)

If we ASSUME that the planet behaves like a gray body with a temperature of 288K and emissivity of 0.615, it is trivial to use the S-B equation to predict 3.3 W/m2 of increased emission per degK of warming. There is “no theoretical intrinsic effect via the GHE which isn’t supported by the theory” involved. This is rubbish.

To validate the above clearly-stated ASSUMPTION, climate modelers asked the same question of about 20 different climate models: What would happen if the planet were artificial warmed 1 degK everywhere, and unanimously got essentially the same answer: 3.2 W/m2/K.

3.6 W/m2 / 3.2 W/m2/K = 1.1 K the no-feedbacks climate sensitivity.

This is the best answer we have for how much warming we expect from 2XCO2. And it is somewhat irrelevant because it doesn’t account for feedbacks.

]]>*“However, the conventional GHE says nothing about what happens to the stratosphere. Nor does lapse rate feedback refer to the stratosphere. Most people think rising GHGs make the atmosphere warmer because they trap heat – which is incorrect. The usual GHE exists only where temperature to falling with increasing altitude and temperature is rising with altitude in the lower stratosphere. See my article on the Schwarzschild equation, particularly the section on the origin of the GHE.”*

I see where it says that in the article. I understand that the GHE theory does indeed say that the upper atmosphere (which I generally is meant to be the stratosphere) will cool for additional surface warming. While I understand (I think) that temperature increases with height in the lower stratosphere, this has nothing to do with the GHE signature for incremental surface/atmosphere warming compared to that of the signature for solar induced surface/atmosphere warming, where for the GHE induced signature the stratosphere will cool (and for solar it will warm). This is best illustrated with diagrams of each signature, but I don’t know how to post them here. I’ve drawn up Windows Paint files that clearly show the two different signatures.

*“In order to prove that recent warming is due to rising GHGs rather than the sun, the IPCC correctly emphasizes that a solar forcing will cause the stratosphere to warm while the forcing from GHGs will cause the stratosphere to cool. The warming is due to SWR, which has nothing to GHGs and the LWR they absorb. So warming has little to do with “GHE” and the initial question I (correctly) addressed concerning 1.2 K of warming in response to 2XCO2. To understand cooling, see my article.”*

Yes, but it’s the 1.2C claimed measure of theoretical intrinsic effect via the GHE which isn’t supported by the theory (and which is my whole point). It’s an amount that will restore balance — yes, but it’s arbitrarily used more or less because the field doesn’t have a valid model or a way to quantify the theoretically supportable intrinsic effect from 2xCO2.

The other main point is that because of this, all of the supposed science involving the sensitivity (and in purported support of the sensitivity) should be taken with a grain of salt. Especially the IPCC’s supported central best estimate of about 3.4K, but even significantly lower results from so-called ‘skeptics’ like Lindze, Spencer, Lewis, etc. are also specious.

]]>“In-any-case OHC, surface temperature and TPW are all increasing rapidly as predicted by models. ”

In general current models use an antiquated concept (“potential temperature”) which has been replaced with “Conservative Temperature”.

Dr. McDougal points out: “present ocean models contain typical errors of 0.1°C and maximum errors of 1.4°C in their temperature because of the neglect of the nonconservative production of potential temperature” …

I have asked a modeller working on huge models (mainframe types) if they (the developers in her team) have adopted TEOS-10 yet, to which she indicated not yet.

There are still some systemic problems with models in terms of ocean atmosphere interactions (e.g. The Ghost Photons).

I guess one has to know a lot about a particular model to know how it handles the “old software thermodynamics” and the “new software thermodynamics.”

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