I’ve watched the video a couple of times now and I’m not convinced these particular experiments say much about the negative effects of increases in CO2 concentrations.

For instance, the European heatwave was accompanied by drought conditions in the South. Wouldn’t it be normal for trees to grow slower and use less CO2 under these conditions? I’m unsure why he presents this as evidence of anything except drought is bad for plants. If he wants to present evidence that higher CO2 levels necessarily lead to more widespread drought, then I’m interested.

And the beetles that were attracted to high-CO2 level soy because a particular pesticide chemical was reduced in the leaves - isn’t this just a cherry-picked situation? What if most plants have increased resistance to pests with greater CO2 levels? I don’t know the answer to that, but I do know that showing one case isn’t convincing and seems anecdotal. There must be other studies showing the benefits of higher CO2 levels, since one scientist in this videos says:

In contrast to what we’ve thought in the past, elevated atmospheric CO2 doesn’t always stimulate plant growth…

Which kind of tells me that elevated atmospheric CO2 levels usually stimulates plant growth, they’ve just found some cases where it doesn’t.

Then there’s the drought in the Western US, and the resulting infestation of pine beetles that are not being controlled by colder weather. Is Sinclair concluding that these warmer temperatures are caused by AGW? He doesn’t present any evidence of that. If he is trying to show how higher CO2 levels don’t always lead to more thriving forests, I could just as easily find a thriving forest and conclude higher CO2 levels are just fine.