There is this wonderful technology that is not man-made which can control the carbon footprint in the least-cost, most-efficient, and least-overhead manner: it is called a "tree".
> A 2019 study of the global potential for tree restoration showed that there is space for at least 9 million km^2 of new forests worldwide, which is a 25% increase from current conditions. This forested area could store up to 205 gigatons of carbon or 25% of the atmosphere's current carbon pool by reducing CO2 in the atmosphere and introducing more O2.
Due to trees being dark, afforestation has a weaker impact on climate change than the stored carbon would make you think. They also evaporate a lot of water, which is also a GHG.
Forests only store carbon when they're young -- mature forests are in a steady state, the rotting wood releases carbon at the same rate that it is absorbed by growing trees.
Mature forests also release methane, which is 25X worse a greenhouse gas than CO2.
This, however, ignores actively managing the forest by clearing dead trees. On the other hand, some amount of dead wood is really important to the forest ecosystem and should be left to rot.
Most trees planted in the world are already cut down too young, while they're still net carbon sinks. A tree planted right now is going to absorb carbon for at least a hundred years. And most timber is used in ways that releases all the stored carbon much sooner than it would happen in a natural forest. Basically the only reasonably sustainable ways to use timber is to either build something lasting out of it or bury it underground.
If it's true they could capture carbon at a cost of $10/ton by weathering rocks it should be much more efficient than trees. It also de-acidifies the oceans.
https://en.wikipedia.org/wiki/Afforestation