One big mystery in the settled science of climate change is why the COVID lockdowns didn’t affect the increase in atmospheric CO2. As Clyde Spencer observes, after looking at the data, and looking at it, and looking at it, “One would naively expect that, if anthropogenic CO2 were important in the growth of the atmospheric concentration, double-digit percentage drops in the three last months of the annual 8-month ramp-up would at least be suggested in the height of the peak (range) or the slope of the curve.” One might also naively expect that if something widely predicted, indeed almost necessary to the theory, did not happen, there’d be some attention to the question of why not and what it means. For instance is it possible atmospheric CO2 is not rising primarily due to human action?
Spencer tackles the iconic Mauna Loa CO2 data with commendable enthusiasm, normalizing the ramp-up graph and checking the R2 values and testing the null hypotheses as fully as anyone could want. And then he declares that something isn’t right.
Apparently those dratted El Niños are involved in the behaviour of CO2 as well as temperature. And, moreover, “If CO2 concentrations were driving temperatures, then one would expect the temperature growth to remain high after a spike in the annual CO2 ramp-up phase. Instead, one observes a sharp decline in temperatures in the years immediately after an El Niño, along with a decline in CO2 concentrations! Clearly, temperature is driving the ramp-up phase variations.”
Aaaack. What? Temperature driving CO2 again? Yes, and this hypothesis must be taken seriously.
The geological record gives strong grounds for thinking increases in temperature typically cause increases in CO2 not the reverse. And indeed, as Spencer rightly says, the 4% of “total carbon flux into the atmosphere” that humans are adding has little or nothing to do with how much gets absorbed by the carbon cycle. And here we feel vindication because of another important point he makes. “The atmosphere can’t tell the difference between anthropogenic sources and natural sources”.
In the conventional wisdom, as he also notes, “It is generally claimed that about half-of the anthropogenic CO2 goes into the atmosphere and is totally responsible for the annual increase of about 2 PPMv annually.” But why? Why would all the natural carbon be absorbed by Mother Nature while half of ours is spat out if she can’t taste the difference? And how?
If it were somehow true, it “would predict a decline in the slope of the CO2 concentrations for the 2019–2020 ramp-up phase of about 9% in April” because of a reduction in our use of fossil fuels during lockdowns.” Instead “It increased!” Spencer’s conclusion is that in fact, “It is just coincidence that the long-term rise is about one-half of the anthropogenic contributions to the atmosphere.”
Those are the fighting words they seem to be, because it means “it appears that temperature is the controlling factor.” Not CO2. The whole theory is wrong because, of all odd things in the settled world of climate science, it doesn’t fit the evidence.
On this point Spencer makes another observation that, once made, seems to us so obvious we are embarrassed not to have thought of it before he made it. “If it weren’t for the economic importance of fossil fuels, we wouldn’t have an estimate of their annual production, consumption, and resultant emissions. The available atmospheric CO2 measurements wouldn’t allow us to make such estimates.”
Eh? Our massive disruption of the ecosystem would not be measurable by looking at the ecosystem? No indeed, because “not only is the anthropogenic release swamped by natural sources, but even subtle changes, such as a decrease in the rate of increase during the seasonal ramp-up phase, cannot be discerned. The working hypothesis of climatologists is that the long-term atmospheric CO2 increase is the result of anthropogenic emissions. However, the evidence supporting that is weak.” To put it mildly.
Spencer makes one more point we cannot resist quoting because it leads into the next item in this newsletter, about the nature of climate feedbacks: “It is difficult for me to accept that there is an unrestrained, positive feedback loop driven by CO2 and resulting in significant surface temperature increase, because, if that were the case, one would expect that we would have long ago passed the so-called ‘Tipping Point’ and be in a permanent ‘hot house’ state, like Venus.”
We didn’t. And it matters. Just as it matters that CO2 isn’t doing what the theory says it should be, and nor is temperature. Leaving what, exactly?