The massive climate report released by the Trump administration on Friday makes clear that the President’s climate policies will destroy every last bit of U.S. (and global) coastal property in the decades to come.

That means more than $1 trillion in U.S. coastal property will eventually be valueless. So the only question is “when” and not “if” that trillion-dollar housing bubble will burst.

The answer appears to be sooner, rather than later, for two reasons. First, the administration’s policies — to abandon the Paris climate deal while working to gut both domestic climate action and coastal adaptation programs — make the worst-case scenarios for climate change more likely while undermining any efforts to prepare for what’s coming. Second, the GOP tax reform bill will directly deflate coastal property values because it targets the tax breaks for the most expensive properties.

Sea levels are rising, and Trump policies will speed that up

Let’s start with how Friday’s congressionally-mandated National Climate Assessment (NCA) makes clear Trump’s climate policies will destroy every last bit of U.S. (and global) coastal property in the coming decades.


The report, the “authoritative assessment of the science of climate change, with a focus on the United States” by scientists from 13 federal agencies — which the Trump administration reviewed and cleared before releasing Friday — paints a grim picture for our coasts.

The scientists can’t rule out eight feet of sea level rise by century’s end (the “extreme” scenario). But then, the Arctic sees upwards of 18°F warming in the 2071-2100 timeframe, so melting of the Greenland ice sheet will be off the charts.

The NCA looks at a variety of scenarios, including ones where the nation and world meet or even surpass the Paris climate targets to minimize total warming. But it also examines higher emissions scenarios where Paris fails. They reflect plausible worst-case scenarios on the business-as-usual path, which is the path that Trump’s policies keep us on.

In those “intermediate-high” and “high” scenarios, sea levels rise 4.9 to 6.6 feet respectively by century’s end. Significantly, they rise 1.4 to 1.8 feet by 2050, which is in the time frame of 30-year mortgages that banks will soon be considering. When banks stop providing those mortgages, property values will plummet.

Remember, the storm surge from future Harveys and Sandys will be on top of whatever sea level rise we see, which is why studies find that, in high emissions scenarios, Sandy-type storm surges occur every year or two by mid century.

The report also looks at the often neglected rate of sea level rise in the coming decades. In the “high” scenario, seas are rising 8 inches per decade by 2050, and 14 inches per decade by 2090. That rise continues to accelerate until it reaches a rate of 2 feet per decade early in the next century.


How exactly do coastal areas adapt to such rapid and accelerating sea level rise? How rapidly do you abandon places that you know will be repeatedly inundated by the combination of sea level rise and storm surge in the coming decades?

And for those who consider such rates of sea level rise unlikely, the NCA has some bad news. The United States is all but certain to see higher “relative sea level” [RSL] rise than the global average especially in the Northeast and the western Gulf of Mexico. In fact for “for high [Global Mean Sea Level] rise scenarios, RSL rise is likely to be higher than the global average along all U.S. coastlines outside Alaska.”

Moreover, the report warns that “climate models are more likely to underestimate than to overestimate the amount of long-term future change.” Again, that means sea level rise is likely to be higher and faster than the report’s projections, especially under Trump’s policies.

The trillion-dollar coastal property bubble is ready to burst

The implications for coastal property values are grave. “The risk will rise as sea levels rise, and when that happens, you’d expect your property value to fall,” as Lloyd Dixon, the director of the RAND Center for Catastrophic Risk Management and Compensation, told the International Business Times last month. “At some point, the property becomes worthless.”

Sean Becketti, the chief economist for mortgage giant Freddie Mac, warned a year ago that the coastal property bubble will burst sooner than expected: “Some residents will cash out early and suffer minimal losses. Others will not be so lucky.”

As Bloomberg put it in April, “Demand and financing could collapse before the sea consumes a single house.”

That process may already be starting. Last November, the New York Times reported that “nationally, median home prices in areas at high risk for flooding are still 4.4 percent below what they were 10 years ago, while home prices in low-risk areas are up 29.7 percent over the same period.”


Jesse Keenan, who studies coastal property, has “begun to see evidence in survey data that middle-income people are leaving Miami Beach and other places with nuisance flooding that makes it difficult to get around at high tides or insure a car,” Scientific American reported back in May. “It’s not out of the question that Miami Beach loses 20 percent of its population and most of those people go to the mainland,” said Keenan. “I’m talking about the next 20 years.”

The GOP tax plan could start to deflate the bubble

The GOP tax reform bill the House of Representatives is considering takes a few whacks at states with a lot of coastal property. As the New York Times reports, it proposes “to put a cap of $10,000 on the property taxes that can be deducted at the federal level; to eliminate the deduction for state and local income taxes; and to restrict the mortgage interest deduction to loans of $500,000 or less.”

The key point is these changes hit the highest-price homes the most — and coastal property values are nearly double the value of similar inland property, according to a Congressional Budget Office study. They could deflate coastal property values more than 10 percent.

Given that the coastal property bubble must burst sometime in the not-too-distant future — and that the early sellers of overpriced coastal property will do a lot better than the later ones — this initial deflation may well hasten the inevitable sell-off.

Here’s the ultimate question for owners of coastal property — and the financial institutions that back them: Who will be with the smart money that gets out early — and who will be with the other kind of money?