If you look at various financial crises throughout history, you'll see that even amid increasingly clear evidence of problems, the status quo is surprisingly sticky. Things move along as normal, and everything seems fine until suddenly... they don't. In hindsight things seem obvious, but at the time it's difficult to know if you are merely flirting with the edge, or you've actually gone over it.

Miami real estate (and other low lying shorefront) isn't quite at that 'oh crap' moment yet. While the evidence for CO2 driven rising sea levels is clear to me, there are plenty of financiers from the previous generation for whom it isn't. And even if they're wrong on global warming, they might be right on sea-walls, pumps and other mitigation methods. The Raising of Chicago lifted the entire city up 3-6 feet with merely 1850s technology, so it's not as if we can't solve Miami's sea level issue with sufficient investment. The issue is who foots the bill, how large it is, and what neighborhoods are left to the sea.