The only problem with that attempted humor is that we already have evidence of many civilizations that were flourishing and are now either buried under thick sheet of ice, or covered under thick canopy of rainforest or lying under a sandbed. Climate changes do occur. Life goes on.
Exactly! And it always has changed. 10,000 years ago sea levels were 800 feet lower. That would really be a problem if buildings lasted, in useful condition, for more than a couple of hundred years. But they don't and human beings like to build new things constantly. So even if the sea level doesn't change most of today's coastal cities will be virtually rebuilt in 200-300 years and that change will go on and on.
I notice you refuse to answer a simple and serious question that I have put to you twice now.