We could easily get to net zero much, much sooner than 2050 by planting a lot more trees. It would be fun and planting trees has many other benefits besides capturing CO2.
Planting more trees (and, more important, preserving existing trees) is an important tool in the toolkit, but shouldn't be overestimated, and I don't think the word "easily" is warranted.
Project Drawdown estimates that 3.2 to 4.96 Gt CO₂/y could be sequestered (through 2050) using a combination of tropical forest restoration, temperate forest restoration, and tree plantations on degraded land. The upper figure is only about 10% of worldwide emissions: significant, but not a game-changer. And the projects involved would be nontrivial, to say the least.
This is the kind of thinking that happens when consultants, smart people, environmentalists, statisticians, and politicians get in the same room to write a report to save the planet.
Planting a tree to save the environment is not simply about the carbon it "sequesters". There are huge positive externalities to planting a tree that come in various forms.
E.g. Something as simple as planting a fruit tree in your backyard. Just imagine these effects:
1. Buying less fruit at shops
2. Less fruit being transported
3. Kids growing up with free food grown from the land
4. People buying land that allows planting a fruit tree
5. People (and their kids that watch) learn about taking care of their surroundings
6. Responsibility to care, prune and water a fruit-bearing tree.
7. Poor communities fed by a tree mean less aid means less 1st world carbon spending for fake 3rd world "feed the poor" brownie points.
8. More fruit rotting on the ground means less fertilizer.
9. More fruits means more birds means more seeds being peppered along the landscape.
Sadly, as with carbon credits, this tree planting concept has been "captured" by opportunists and they just have you give them money so they can "plant" a tree easily on your behalf somewhere halfway around the world so you don't have to worry about it.
I'm honestly not sure what your point is. Are you saying that, if there was less cold quantitative analysis of the global CO2 potential from forest management, people would be planting more trees in their local neighborhoods?
Absolutely, trees can provide many benefits separate from CO2 absorption. I was simply responding to GravityLab's comment about CO2. However, it's also worth noting that planting the wrong trees or in the wrong place can backfire: displacing more appropriate vegetation; fire risk; etc.
Another advantage to grasslands is that grasslands help control the tick population. Ticks like shady spots like trees and bushes. They dry out in grasslands.
Every square meter of forest absorbs enough CO2 to offset about 1 Watt of carbon fuel use. The average US inhabitant uses about 10kW on average. About half of US energy use is from fossil sources and the population is about 300 million. So we'd need 150 million new hectares of forest, growing forested land from 1/3 of the country to 1/2. Which is honestly a lot more doable sounding than I'd thought it would be before running the numbers.
EDIT: Eventually the forest will climax and start emitting as much CO2 as it absorbs but that's a lot of time to solve the problem at a more fundamental level.
Yes, planting trees is easy but it is the maintenance. To make sure the trees planted are taken care off until they are grown enough to survive on their own is a task and an expense.
It's a significant amount of trees - smaller than I thought, but perhaps the largest megascale project ever attempted. ~230B trees which is ~7.6% of the global tree stock.
Project Drawdown estimates that 3.2 to 4.96 Gt CO₂/y could be sequestered (through 2050) using a combination of tropical forest restoration, temperate forest restoration, and tree plantations on degraded land. The upper figure is only about 10% of worldwide emissions: significant, but not a game-changer. And the projects involved would be nontrivial, to say the least.
If you're interested, I dug into this topic in some depth in a blog post a little while back: https://climateer.substack.com/p/forestation-2.