>>flir+yU1
I've thought about this as well. It's feasible to move soil only to certain regions. Greenland and Antarctica aren't among them (remember the ice shields; they will continue to scrape all the soil as they melt). Some islands in Antarctic Ocean could potentially sustain a population of 20-40k. However, you need to start moving the soil now, but you will also need to develop methods of preserving this soil until it is needed, because right now it will be useless and it will be eroded by wind and hydro factors. What might happen is a gradual migration towards the poles on the Americas and Eurasia, moving the soil as migration progresses. This will be bloody and ruthless. But none of these solutions take into account the "exponent", and there is no way to forecast if a Venus atmosphere scenario will occur or not due to the water vapor.
Edit: good point in the next comment, expect sea levels rising for at least 10m.