The question is what’s our exposure on global warming.

For one small part of it we may need to build a 10 foot high sea wall on the entire world coastline. My guestimate is that that would be about $5,000/ft for the cost of straight forward construction on solid ground. It would be far less than the reimbursement of property owners for the first 10 ft elevation of their property. The earth’s coastline is about 844,000 km, though I doubt that includes the intricacies of wetlands and estuaries etc.

The places where environmental protection, waterfront access or shipping locks and other things are needed would also add to the cost. Maybe you’d just say screw it and screw them with half the world’s coastline and cut the losses with that part of it. The places that wouldn’t be saved from rising waters by a sea wall include big sand bars like Long Island New York. Continue reading Construction Estimate →