Coastal Flooding Could Cost $1 Trillion Annually by 2050

A new study appearing in Nature Climate Change quantifies the damage that rising seas and increasing coastal development could inflict on the world's coastal cities, reports Brad Plumer. The cities that will be hit the hardest as a percentage of their GDP include New Orleans and Guangzhou, China, as well as several cities in developing countries.   

The $1 trillion estimate is based on an assumption cities will proceed with business as usual. However, there are ways that cities can mitigate the damage that will be done. 

"By contrast, if coastal cities worked to bolster their defenses — from levees to pumps to movable barriers — and improved flood monitoring, then the average annual losses go down to $63 billion per year. That’s still a big increase, but it’s not nearly as steep. (That said, the authors estimate those defenses could cost around $50 billion per year between now and 2050.)," explains Plumer.