alea, you bring up sequestration, my thinking is simply that we migrate to a much higher flux rate. Yes, if by accounting we determine we have more carbon than we need, then we bury some of it. The current issue is we liberate it faster than we fix it (fix in the chemical vernacular of carbon fixation, nitrogen fixation and so on, not in the more common notion of remedy something that is broken sense).
But we do not need to find anything. We have all of these things. Right here, right now, we have have the tools, we have the technology, we have the manpower, we have the budget, we don't need to find anything (unless accountants determine that the total carbon amount is more than we need or want, in which case we bury some of it) I doubt that. There are 7 billion of us. And there are other animals too, Animals we like. I am inclined to think that this surplus of carbon is not a surplus at all, we just need to insert ourselves, harness, and better realize the benefits.