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Showing posts with the label planetary temperature

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 ...

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...