As you should know by now, I have some real problems with the way climate science, largely personified by the IPCC in today’s world, does its bookkeeping. As a result good data that has been gathered is sometimes mishandled on the books, and when good data is needed, but still missing because of various difficulties or oversights, the hole that remains may get glossed over on the books, replaced by estimates or assumptions that could be far off base. We are in a situation, properly called a crisis, where it is important that high quality information be passed on to the public as an aid to formulating the best response. Bad bookkeeping, in my view, has become a source of distortion and misconceptions in setting up the message, thus damaging the potential response. In short, I think the situation is worse than what we are told, that we have dug ourselves into a hole that is practically impossible to climb out of. I will be telling you exactly how I’ve come to that conclusion. It will take more than one of these daily letters to do so. Also, please observe that I am still learning things, and often need to make adjustments to some early ideas. I earnestly want all of the weakest ideas to be found and corrected as quickly as possible, without worrying about possible embarrassment.
How and where does bookkeeping enter into the picture? Let’s get right to it, using the IPCC’s tables of radiative forcing as a foundation. These are published with each new report, in ways that are kind of buried away somewhere. I was just recently lucky enough to stumble into the latest of them, as picked up from a story in the RealClimate website: https://www.realclimate.org/index.php/archives/2021/09/the-definitive-co2-ch4-comparison-post/. (This story is worth reading and saving because of its additional information.) Here’s the chart it contains:
I also want to show the previous version of the chart from 1750 to 2011, because of some noteworthy changes that have been made since thsn and will need to be referred to at times:
Neither one of these has any mention at all of the most powerful of all the greenhouse gases, water vapor, but that does not mean the expression of its powers has been neglected. The IPCC has taken care to see that they are included, by simply adding them on, rather arbitrarily, to the powers of CO2. When you read 2.1 W/m2 on one chart, and 1.8 watts on the other—an inexplainably large gain for just eight years—roughly half of those numbers in both cases came from and really belong to water vapor. The alternative would be to give water vapor its own line on the chart, which for some reason they want to avoid. Anyway, the same kind of treatment accorded to CO2 is not replicated for any other forcings on the chart, which I think is pretty sad from a scientific point of view. The IPCC ends up with an assumption that CO2 is the only “ordinary” GHG capable of generating increases in water vapor content as a feedback to its heating effects. The same thing goes for all of the other forcings, other than GHGs, including the negative ones whose cooling power might very well cause water vapor in the atmosphere to contract, by stimulating condensation for example. In yesterday’s letter I wrote, in a derisive way, about the absurd concept that evaporation might depend on how the water it comes from was being warmed. This is precisely what I had in mind.
Now we can dig more deeply into why this kind of bookkeeping causes real-life problems. When the IPCC assigns the power of water vapor to CO2, and nothing else, CO2 is made to look twice as strong as any other forcing. This is an obvious distortion of physical reality, and it becomes directly embedded in the messaging that is delivered to the public. The need to curtail CO2 emissions is indeed very real, but that is not a good excuse for overemphasizing this need in relation to the similar need to curtail other forcings that also have water vapor feedback effects that in fact amplify the warming they do. Methane is the most critical of these, and there is no way to safely assume that its concentration in the atmosphere will not keep on growing in the years ahead.
This leads us directly into the recognition of a potentially very damaging problem due to the bookkeeping error, the distortion of climate forecasting. The models that do the groundwork in predicting the future all (I think all) incorporate the same misconception. They work by plugging in various future assumptions for physical concentrations of the different forcings, which can then in each case be expressed, more or less accurately, in terms of watts per square meter. CO2’s forcing will always end up being doubled because the water vapor feedback is automatically locked in. Since CO2 is the strongest ordinary GHG to begin with its forcing power will tend toward a dwarfing of the others. Just as CO2 is “locked in” to possession of the feedback, all the others are “locked out.” Literally. Methane will always be locked out of having a water vapor feedback even when models imagine its concentration forging ahead for some strange reason. Enough for today, more tomorrow.
Carl