1/9. The beneficial effects of rising CO2 levels are not "reversing." Don't let Bonus mislead you, Jim. He really just doesn't care about facts.
Here's AR6 WG1 Table 5.1, which shows how natural CO2 removals are accelerating:
ipcc.ch/report/ar6/wg1โฆ
I annotated it here:
sealevel.info/AR6_WG1_Table_โฆ
2/9. Here're the relevant bits:
sealevel.info/AR6_WG1_Table_โฆ
As you can see, as atmospheric CO2 levels have risen, the natural CO2 removal rate has sharply accelerated. (That's a strong negative/stabilizing climate feedback.)
3/9. AR6 FAQ 5.1 also shows how both terrestrial and marine carbon sinks have accelerated, here:
ipcc.ch/report/ar6/wg1โฆ
Here's the key graph; I added the orange box, to highlight the only part climate activists notice.
sealevel.info/AR6_FAQ_5p1_Fiโฆ 4/9. Here's the caption, saying that natural removal of carbon from the atmosphere is NOT weakening.
(They should've stopped with the word "No." The rest is a muddled attempt at "spin.")
The AR6 authors did PREDICT a "decline" in the FUTURE, "if" emissions "continue to increase." But it hasn't happened yet.
sealevel.info/AR6_FAQ_5.1_NOโฆ5/9. What's more, the "decline" which they predicted was NOT for the rate of natural CO2 removals by greening and marine sinks, anyhow. Rather, if you read it carefully, you'll see that that hypothetical "decline" was predicted just for the ratio of natural removals to emissions.
6/9. What's more, their prediction was conditional, depending on what happens with future emissions ("if CO2 emissions continue to increase").
Predictions are cheap. MY prediction is that natural removals of CO2 will continue to accelerate, for as long as CO2 levels rise. (MY prediction is based on scientific evidence, not political spin.)
7/9. The "fraction" which AR6 predicts might decline, someday, does NOT represent anything physical, anyhow. It is one minus the equally unphysical "airborne fraction."
Our emission rate is currently about twice the natural removal rate, so if emissions were halved, the removal "fraction" would be 100%, and the atmospheric CO2 level would plateau. If emissions were cut by more than half then the removal "fraction" would be more than 100%, and the CO2 level would be falling.
8/9. This recent study quantifies the benefits of rising CO2 levels for several major crops.
nber.org/papers/w29320
Their results are toward the high end, but their qualitative conclusion is consistent with many other studies. They reported, "We consistently find a large CO2 fertilization effect: a 1 ppm increase in CO2 equates to a 0.4%, 0.6%, 1% yield increase for corn, soybeans, and wheat, respectively."
9/9. If you recall that mankind has raised the average atmospheric CO2 level by 140 ppmv, you'll recognize that those crop yield improvements are ENORMOUS!
Here're some additional relevant papers:
sealevel.info/negative_sociaโฆ
sealevel.info/negative_sociaโฆ