Private communication Howard Cork Hayden to John Shanahan
Asking the wrong question - A Fool's Errand Howard “Cork” Hayden January 12, 2022 Imagine a large room with perfectly insulating walls. The room contains chairs, tables, books, sheets of paper, pitchers and glasses of water, some flowering plants, and so forth. Now comes the question: “If we add some heat (say 1 MJ) to the room, how much does the temperature rise?” To get the answer, we would have to know the heat capacities and the masses of everything in the room. With that data and a lot of calculation, we could figure out the temperature rise. Now we come to the larger problem of the surface of the earth: “If we add a certain heat flux (say 1 W/m2) all over the surface of the earth, how much would the temperature rise? One watt per square meter of heat added to a shallow puddle will have an entirely different effect than one watt per square meter of a 10-meter column of water in the ocean. What about adding the heat flux to solid rock, sand, tree leaves, Antarctic ice, and so forth? For a rocky surface, how much heat goes into warming how much rock, and how much heat is radiated away? So many assumptions are involved that the calculated temperature rise can be pretty much anything. Start programming your supercomputer! Asking how much temperature rise you get by adding some heat flux is a fool’s errand. You can get a huge range of answers based on whatever assumptions you make. Now turn that unanswerable question around and ask an answerable question: “If the temperature of the surface rises by (say) 1ºC, how much more IR does it emit?” The unambiguous answer lies in the Stefan-Boltzmann radiation law, something found in every elementary college physics textbook, and it only requires a slide rule to get the answer: 5.48 W/m^2, for surface temperature of 289K. The same law says that a temperature rise of 0.67ºC will increase IR by 3.7 W/m^2, the same as the “radiative forcing” the IPCC says would due to doubling CO2. (Better yet, 0.54ºC arising from Happer's 2.98 W/m^2 from CO2 doubling.) 1
The IPCC claims that the temperature rise of the earth for CO2 doubling will very likely be between 2ºC and 5ºC, with a best estimate of 3ºC. The increases in surface IR for these cases are, respectively, 5.5, 27.4 and 16.4 W/m^2. One wonders how these values are consistent with the 3.7 W/m^2 radiative forcing due to CO2 doubling. Isn't it amazing what you can do with a supercomputer?
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