We would need to recreate the Azolla Event: https://en.wikipedia.org/wiki/Azolla_event

Or even the Carboniferous period where microbes could not digest lignin and cellulose: https://en.wikipedia.org/wiki/Carboniferous

Which is impossible. We simply need to stop digging fossil fuels out of the ground in order to burn them.

But if a whole forest is created and maintained, even as trees die and rot they build the biomass of the soil and undergrowth: every ton of life is carbon and heat energy captured - individuals live and die, but the overall biomass can increase, capturing carbon and energy in the form of healthy ecosystems.

As another commenter pointed out, if humanity just left earth tomorrow, it would take eons for CO2 ppm to fall, so we should be doing something proactive. Plus, planting and caring for trees is something everyone can do and gets us away from the “wait for a super villain billionaire to solve it” mentality.

Edit: thanks for the link to Azolla, hadn’t heard of that

We need more trees for sure, but at the same time would would need to put huge efforts in forest fire prevention otherwise poof, all that hard work trees do sequestering CO2 literally goes up in smoke.

Given how slow most types of trees grow that seems completely unfeasible unless we give up most meat (taking space that we now use for growing animal feed).

(Yes, we have a lot of space in the desert, but studies show limited effect on global warming from planting anything there once you account for how well sand reflects heat back into space).

There was a recent Youtube video that explained how this isn't quite accurate:

https://www.youtube.com/watch?v=sGG-A80Tl5g

I'll save you the time (though you should watch it).

1. Much of the animal feed comes from agricultural byproducts. As an example, we eat corn on the cob, but much of the corn stalk is inedible to humans, but can be made into products for animals.

2. Much of the land used for animals is not suitable for growing crops. Some is, but it's not a 1:1 swapability factor.

1a) Cut down lots of trees 1b) Turn them into charcoal 1c) Bury the charcoal in agricultural land, sequestering the carbon and increasing yields