On a predictably gorgeous South Florida afternoon, Coral Gables Mayor Jim Cason sat in his office overlooking the white-linen restaurants of this affluent seaside community and wondered when climate change would bring it all to an end. He figured it would involve a boat.
When Cason first started worrying about sea-level rise, he asked his staff to count not just how much coastline the city had (47 miles) or value of the property along that coast ($3.5 billion). He also told them to find out how many boats dock inland from the bridges that span the city’s canals (302). What matters, he guessed, will be the first time a mast fails to clear the bottom of one of those bridges because the water level had risen too far.
“These boats are going to be the canary in the mine,” said Cason, who became mayor in 2011 after retiring from the U.S. foreign service. “When the boats can’t go out, the property values go down.”
If property values start to fall, Cason said, banks could stop writing 30-year mortgages for coastal homes, shrinking the pool of able buyers and sending prices lower still. Those properties make up a quarter of the city’s tax base; if that revenue fell, the city would struggle to provide the services that make it such a desirable place to live, causing more sales and another drop in revenue.
And all of that could happen before the rising sea consumes a single home.
As President Donald Trump proposes dismantling federal programs aimed at cutting greenhouse gas emissions, officials and residents in South Florida are grappling with the risk that climate change could drag down housing markets. Relative sea levels in South Florida are roughly four inches higher now than in 1992. The National Oceanic and Atmospheric Administration predicts sea levels will rise as much as three feet in Miami by 2060. By the end of the century, according to projections by Zillow, some 934,000 existing Florida properties, worth more than $400 billion, are at risk of being submerged.
The impact is already being felt in South Florida. Tidal flooding now predictably drenches inland streets, even when the sun is out, thanks to the region’s porous limestone bedrock. Saltwater is creeping into the drinking water supply. The area’s drainage canals rely on gravity; as oceans rise, the water utility has had to install giant pumps to push water out to the ocean.
The effects of climate-driven price drops could ripple across the economy, and eventually force the federal government to decide what is owed to people whose home values are ruined by climate change.
Sean Becketti, the chief economist at Freddie Mac, warned in a report last year of a housing crisis for coastal areas more severe than the Great Recession, one that could spread through banks, insurers and other industries. And, unlike the recession, there’s no hope of a bounce back in property values.