I wrote about this in a previous HN thread a few years back. Not clear that it's a great idea: https://news.ycombinator.com/item?id=28593452#28599027
It is that we start at the periphery, very gradually going inward over a thousand year period. We should have enough data of the effects of our peripheral perturbations in the first few hundred years. It should provide a testable model for how to proceed safely as we go inward.