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sat posted: Sat 2017-10-14 09:43:53 tags: motion
Stepping up the "motion" process, my main driver all along has been figuring out where exactly is safe to live if ALL the ice melts. Not just the ice caps - there are massive landlocked glacial sheets in Greenland, etc. too. A top Google result from NatGeo says 216 feet. Another high-ranked result says 230 feet (70 meters). A third source says there's overall about 80 meters of sea level bound in glacial ice, but dramatic sea level rise will undoubtedly erode softer surfaces, so a silty (relative) lowland at 85m elevation, with downstream ocean exposure, could be in jeopardy. It depends where the bedrock is.

Climate science is anxious because we don't know how fast all the ice will melt, but we do know it's happening faster than predicted and the conventional models imply we're approaching an inflection point beyond which it will be increasingly difficult to reverse. I think most likely we'll figure out how to bind carbon on a massive (terraforming) scale and if necessary, purify and pipe marginal water to refreeze somewhere, at the same time we're learning to invest massively in wind and solar farms and build artificial islands. China, with their huge infrastructure investment of the past couple decades, is poised to lead that initiative. The question is, where will the break-even point be? That is, how much will sea level rise before we stabilize and start reversing? There's no payoff potential for risking homesteading at a lower elevation, so 270' is a fair minimum and 300' elevation gives you some breathing room for erosion.

If you Google "wake co nc geology" there's a Wake County parks site with a PDF showing the geological foundations of the Raleigh area. It shows inactive faults; there are no active faults and it's simply not a quake-prone region. But in a max-sea-level-rise scenario it can help inform as to where erosion will be most likely.

Returning to the topo map, we see there's a lot of elevation differential in Raleigh. Parts of it are below the "safety line". Even heading west there's a trough before you reach the solid safety of the Blue Ridge Mountains.

Raleigh public pools