The best way to cheaply remove CO2 is to plant more trees. The simplest solution is still the best: it requires no new technology, can scale itself when the trees reproduce and is eminently accessible to all sorts of people, all around the globe. As an added benefit, some trees can even give fruit... which are delicious.
Quote from the article: "Climate scientists have calculated the effect of increasing forest cover on surface temperature. Their conclusion is that planting trees in the tropics would lead to cooling, but in colder regions, it would cause warming."
Don't forget: when a tree dies, the CO2 it absorbed is (indirectly) released back into the atmosphere. Unless you store the wood somewhere and keep it from being consumed by nature.
On an individual tree level, yes. But planting trees usually implies either:
- Designating new areas for entire forests to be grown (which all together is a store of CO2, even if individuals die and rot)
- Many individual trees in towns/cities, which would presumably be replanted if they die and so, again, in summation are a store of CO2.
Or just encourage everyone to have oak panelling, wood floors, and a huge excess of fine wooden furniture
