How many of those companies actually put atmospheric carbon back in the ground, sequestered in a form that it stable for at least a couple of generations? As far as I'm aware you either pay for some trees not being cut down (for how long?) or you pay for measures that prevent carbon emissions by e.g. subsidizing more efficient cooking stoves. Both methods are not completely useless (which I why I said "mostly"), but they're not really unburning the fossil fuels I used. They also don't scale very well.

I'm actually looking for ways to offset my emissions, so I'd really appreciate some pointers if you're familiar with the space.