Coastal defenses reduce the risk of floods today, but they also attract population and assets in protected areas and thus put them at risk in case of the defense fails, or if an event overwhelms it.
In terms of the overall cost of damage, the cities at the greatest risk are: 1) Guangzhou, 2) Miami, 3) New York, 4) New Orleans, 5) Mumbai, 6) Nagoya, 7) Tampa, 8) Boston, 9) Shenzen, and 10) Osaka. The top four cities alone account for 43% of the forecast total global losses.