With 200 feet sea rise all coastal cities around the world would disappear. I live in Greece and my house is just 84 feet above sea level. With a 200 feet rise

With 200 feet sea rise all coastal cities around the world would disappear. I live in Greece and my house is just 84 feet above sea level. With a 200 feet rise two thirds of Athens would submerge. All islands will go under. At least half the population here lives in cities near the sea. Sure, there's a lot of land to move inland but the cost to do so would be substantial. I don't even want to think about it.