If Each of Us Planted a Tree, Would It Slow Global Warming? | WIRED
https://www.wired.com/story/plant-a-tree-for-climate-change
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Damn. That sucks. Even with 7.5 BILLION trees, it makes only a tiny dent in the carbon dioxide level. Yes, we made a lot of assumptions, and some of them are obviously wrong—but they’re not crazy-wrong. For example, we simplified by saying the trees are all the same. But allowing them to be different wouldn’t change the result if our generic tree is a good middle-of-the-pack average. The real question is whether our model is biased in one direction or the other.
One obvious bias is that we assumed away branches. (I’m trying to picture a poor village smithy standing under a non-spreading chestnut tree …) But how much more carbon would we trap with branches? Twenty percent? Even if it doubles the reduction, the atmospheric concentration of CO2 still rounds off to 400 ppm.