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Showing posts with the label greenhouse effect

Quantifying the Relative GHE for Various Planets

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In a previous post I debunked a silly paper from Holmes that claimed to be able to calculate the 1-bar temperatures of a planet knowing only the ratio of the TSI values for the two planets and the 1-bar T for the second planet. Holmes' used the following equation. T1 = ∜rTSI*T2 I showed that this equation doesn't work because it ignores both the GHE and albedo. It gives the superficial appearance of working if you calculate 1-bar T of Earth from Venus and vice versa, since Venus has both a strong albedo and GHE. But even then it only "works" if you use 340 K for Venus' 1-bar T, and NASA currently reports the 1-bar T for Venus to be 360K. And this formula doesn't work for any of the possible calculations involving Titan at all, so it has at best a 67% failure rate (if you accept 340 K for Venus). One thing I thought was interesting, though, is that if you use ASR instead of TSI, the results were still wrong, but they were wrong in such a way that indicated the...

Holmes on the Relationship Between TSI and Temperature

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I was just made aware today of a paper published in 2019 by  Robert Ian Holmes on the Relationship Between TSI and Temperature at 1-Bar Pressure. The paper claims to be able to "predict" planetary temperatures at 1-bar pressure on the basis of TSI values of rocky planets and moons with a surface pressure of 1-bar or higher. The logic is that if you calculate the relative TSI between two planets (rTSI) you can multiply ∜rTSI by the 1-bar temperature of one planet to get the 1-bar temperature of the other. We can summarize his math as: T1 = ∜rTSI*T2 There's no way to derive this equation from any known relationships; Temperature relates only to the absorbed fraction of TSI; the reflected fraction has no impact on T. There are three rocky planets and moons that have as surface pressure of 1-bar or higher. Here they are with Holmes' values for their 1-bar temperatures: Venus (340K), Earth (288K), and Titan (85-90K). Holmes shows his calculations below. This superficially ...

A New Paper Makes Low Sensitivity Models More Implausible

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A paper was published this week that argues that low-sensitivity models do a poor job of reproducing CERES-derived EEI trends. In the words of the paper, the authors used CMIP6 models "to illustrate that low climate sensitivity models have an EEI trend behavior that is inconsistent with the satellite-derived EEI trend." Even though models with an ECS near 3°C do a good job of reproducing current warming, CMIP6 models often differ in the in EEI trends. For instance, The CERES data show a stronger trend in EEI than the multi-model CMIP6 mean and higher EEI in 2023 than any of the CMIP6 models. However, for individual CMIP6 models and ensembles, EEI is comparable to or higher at other periods than the CERES value in 2023. The difference in trends can be seen by comparing the red CERES line to the black CMIP6 model mean. Even though the interannual variability in the CMIP6 models is consistent CERES observations, the observed trend in EEI, especially since about 2010, is higher t...

A Simple Test of Nikolov's Alternative to Greenhouse Gases

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This is a follow up to a post about Nikolov & Zeller here , updated on 4/14/2025. In a recent manuscript [1] "published" on the so-called Science of Climate Change blog, Nikolov and Zeller (NZ) articulate how they believe that the Earth's temperature remains warmer than its effective temperature. Without getting into whether that amount should be considered 90K or 33K, it's clear that for them the long-term baseline temperature of earth is determined solely by total solar irradiance (TSI) and atmospheric pressure (P). Here it is in their words: NASA planetary data indicate that the radiative “greenhouse effect” does not exist in reality. That’s because, across a wide range of planetary environments in the Solar System, the long-term (baseline) global surface temperature on rocky planets and moons is fully determined by the mean Total Solar Irradiance (i.e. distance from the Sun) and total surface atmospheric pressure. Variability on this long-term baseline temper...

Stefani's Paper Illustrates the Failure of MDPI Peer Review

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A recent paper[1] published in the MDPI journal Climate by Frank Stefani provides a wonderful illustration of why we should never treat papers from MDPI journals as having any competent, let alone robust peer review. This paper argues that TCR = 1.1°C (0.6°C - 1.6°C) for doubling CO2. I'm not going to evaluate the entire paper here, since that would take too much time. The paper does make some counterfactual claims, like there's a "nearly perfect correlation of solar activity with temperatures over about 150 years." That's objectively false, but the correlation between CO2 forcings and GMST has an r^2 = 0.88. There's also some comical contrarian alarmism in this paper: "we fear that the huge Milankovitch drivers will—perhaps much too soon—massively interfere with the solar and anthropogenic factors that were considered in this paper." There's a lot we could say about this paper, but I want to focus here on some elementary math errors that would ...

Does Climate Science Assume the The Earth is Flat?

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On Facebook I recently came across a character by the name of Joseph Postma. I had come across some of his ideas on YouTube in the past and had quite a laugh at some of the nonsense that he puts in his videos, but recently Postma started participating in a group that I participate in, so I've interacted with him personally. For those of you unfamiliar with him, his ideas should best be understood as coming from the lunatic fringe of contrarian thinking. In fact, I'm seriously tempted to think that he doesn't actually believe what he says, but he's basically seeing how absurd he can be and still get people to believe him. To be sure, he has not yet convinced even the most radical of people blogging on some of the most popular contrarian sites. I mean, WUWT has posted criticisms of his views, Willis Eschenbach has publicly disagreed with him, and Roy Spencer has devoted at least one post  to responding to his claims. Even David Burton has taken issue with Postma. In othe...

Can Atmospheric Pressure or Density Explain the Earth's Temperature?

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In my last post , I responded to the claim that the greenhouse effect contradicts the second law of thermodynamics. When people make this claim, I often ask what it is that makes the Earth's temperature warmer than its effective temperature if there's no greenhouse effect. The response I get back usually has to do with what can only be described as an ill-informed, "crackpot" theory arguing that this is due to atmospheric pressure or density. Using the ideal gas law, critics of science calculate the temperatures on planets like Venus, Earth and Mars from other known quantities in the ideal gas law, and then assert that this means planetary temperature is due to density or pressure instead of GHGs. There are multiple versions of this, all of which claim either that there is no greenhouse effect or that the greenhouse effect has nothing to do with greenhouse gases and everything to do with atmospheric pressure and/or density. To my knowledge the original version of this...

Does the Greenhouse Effect Contradict the 2nd Law of Thermodynamics?

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Occasionally I hear people claim that the greenhouse effect isn't real because it would contradict the 2nd law of thermodynamics. The idea behind this is that the atmosphere is cooler than the Earth's surface, and the 2nd law of thermodynamics says that heat always goes from hot to cold. Therefore, the Earth's atmosphere can't heat the Earth's surface. Therefore, the greenhouse effect can't exist in a universe in which the 2nd law of thermodynamics is operable. A Simple Explanation The silliness of this objection can become apparent with a simple analogy. If you walk outside with a thin t-shirt on a cold day (let's say 20°F), you'll quickly feel cold, and the surface of your skin will be significantly colder than normal. If you find a winter coat outside, its temperature will be 20°F. But if you put it on, you will begin to warm. It's not that the coat is generating heat and sending it to your body. It's simply slowing down the rate at which ther...