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by GravityLab 972 days ago
This can be accomplished by planting trees.

https://logtrees.com/blog/the-simple-math-behind-planting-tr...

4 comments

Except, half of all planted trees are dead within 5 years. And my guess is that the easily available planting locations of people planting trees close to them are less likely to survive.

Second, it is rather hard to find a solid source for that CO2 number. https://onetreeplanted.org/blogs/stories/how-much-co2-does-t... supported a figure that is half that one.

Third, CO2 in trees does not necessarily REMAIN in trees. Need I remind you of last summer's wildfire problems? To fix the wildfire problem, we need to remove large amounts of dangerous overgrowth that a century of fire prevention has encouraged.

Fourth, the current trend is towards losing forests, not gaining them. It is easy to point to land and say, "Add forest there." But people living there who want to plant soybeans and raise cattle have different ideas. That's why rainforest is disappearing. What do you wish done with those inconvenient people?

Yeah, planting trees sounds great. But it is not likely to be a workable solution in the real world. Though it has promise as one of many pieces of a workable solution.

1. The average tree's lifespan is a lot longer than 5 years. It's more like 300-400 years. I've not seen any sources saying that half of all planted trees are dead within 5 years. Even if that is true, 5 years is enough time to keep replanting and maintaining the total number of trees much higher. People can tend to the trees they plant.

2. I got my number for CO2 capture per tree from the U.S. Department of Agriculture, the Arbor Day Foundation, and the European Environment Agency.

3. I don't think the wildfires materially impact the calculus.

4. There is a lot of land available for reforesting. This is not the same as saying that we should take back land that is used for farming. I would say that agriculture is going to innovate too, with vertical farms and more efficient usage of land where land is still necessary. We can start with land that is already available for reforesting rather than starting with squabbling over land that is now already used as farmland. Making farmland more efficient and innovating with vertical farms will let markets take care of inefficient and unnecessary land usage.

5. Planting trees for CO2 capture is a temporary solution. Eventually machines will sequester CO2 far more efficiently. Planting trees in general is nice for many other benefits too, not just the carbon capture. But yes, planting more trees is not the only thing we need to do.

https://www.earth.com/news/half-of-plants-used-in-reforestat... gives a reference for half of planted trees dead in 5 years.

Your CO2 capture figure is widely quoted, including in those places. But can you find a scientific paper that it goes back to? I'm a little wary of figures that I can't find a real reference for.

Not enough. We both cut down trees and burned underground carbon stores.

Merely replanting trees goes part of the way but it can’t address the whole issue.

The calculations you showed seem to be about blunting annual emissions. But we still have all the excess we previously emitted which has warmed the atmosphere. We need to deal with that eventually.

The amount of trees that could be planted would capture more than the airborne excess carbon, which means they would be capturing previous excess too. Since we're really close to peak global CO2 emissions, this means the new trees would be a carbon sink that keeps capturing excess carbon for at least decades, until far better capture solutions are created than long disruptive pipelines.
There is only so much ground that can be covered with trees, and it stops those areas being used for other purposes.

There are no practical limits for how much CO2 you can store underground!

"There are no practical limits for how much CO2 you can store underground! "

Energy cost is the practical limit.

There is already enough land available for enough new native trees to capture more CO2 than is emitted into the atmosphere each year. This is before considering recovery of additional brownfield sites, becoming more efficient with industrial and agricultural land usage, and setting more land aside for planting additional trees.

With the full potential unlocked, we'd be able to plant so many trees that they'd capture 2x or more of the total CO2 emissions (total emissions, not just the airborne excess) which means we'd start capturing the past excess emissions as well.

> There is already enough land available for enough new native trees to capture more CO2 than is emitted into the atmosphere each year.

Since land is finite and the number of new years is not, that can only be true for a finite number of years.

Also, we need to capture more CO2 than is emitted to get down to natural levels.

There is already enough land available to capture enough CO2 to bring us down to natural levels if we plant those trees.
Silvopasture exists. We are becoming reacquainted with better farming practices. Homes, offices, and other kinds of buildings are built in forests all the time. Plenty of opportunities for recreation.

CO2 stored underground in the form of plants dying and rotting for the benefit and use of other plants is also "carbon capture".

There are also other uses for captured CO2. Better concrete, carbon nanotubes, etc.
It cannot. Although reforestation is still a great idea and can result in significant GHG reductions if managed properly.
Yes it can. The number of trees that could be planted are enough to capture airborne excess CO2. I'm glad there's technology via pipeline but it needs to mature more. We need better solutions than really long and disruptive pipelines, and planting a lot of trees buys us a lot of runway.
You’ve said this twice now, but do you have a source?

What number of which trees is the bough to capture excess co2 from ground and surface sources?

Where could we put all this trees?

Planting trees can certainly do a lot, but it is insufficient. If you went all in on "nature based" solutions, it gets you to around 15-20% of needed reductions. This would require a global reshaping of land use policy.

https://www.american.edu/sis/centers/carbon-removal/fact-she...

Anyone who says that they have one thing that will solve climate change is either uninformed or lying.