Doing Nothing: Flood Losses In World’s Coastal Cities Could Reach $1 Trillion per Year
In a new study, published today in Nature Climate Change, economists have tallied up the future costs of flooding in the 136 largest coastal cities in the world, and determined that if we do nothing at all, the bill in 2050 could be upwards of $1 trillion each year. However, if we invest now in flood defenses and other measures, the bill will “only” be some $60 billion. The author tells Mother Jones that without more preparation, “even in cities that are very well-protected today, losses will reach levels that are completely impossible to imagine.”
The risks in coastal cities are compounding: sea levels are rising while coastal lands are subsiding. Meanwhile, coastal populations are rising as well as coastal property values. The study points out the logical result: when floods occur in the future, they will be worse, they will affect more people and properties, and the same damage will be more costly.
New York, Miami, New Orleans, Boston and Tampa are among the top 20 global cities with the most at stake. Guangzhou, China and Mumbai, India are at the top of the list.
It will take not only stronger infrastructure and better-engineered flood defenses, but also better management of growth and development along vulnerable shorelines, and well-managed retreat from some of the most vulnerable locations. Preparing now — not later — will help keep costs down.
UPDATE 8/19: More here from Climate Central.