Thomas Peterffy became one of the world’s richest people by mastering risk on Wall Street. Building his Mediterranean-style mansion seven years ago on a vulnerable stretch of Florida’s Palm Beach Island was a matter of seeing the odds clearly once again. The consequences of climate change will play out over decades, and Peterffy is 76 years old.

“I don’t have a care about it at all,” he said over lunch at Mar-a-Lago earlier this year, just down the street from his home. The founder of Interactive Brokers Group has a fortune of more than $21 billion, according to the Bloomberg Billionaires Index.

“If something needs to be done to save it,” he added, “it’s not going to be my problem.”

The town of Palm Beach is busy adapting to the risks of a warming planet, even if there appear to be fewer worriers among the buyers and speculative builders on the island. Some of the lowest-lying properties in the U.S. are seeing the highest-flying prices. The real estate website Zillow estimates the value of Peterffy’s home at $52 million. This year a new nine-bedroom mansion with toes-in-the-sand views sold to financier Scott Shleifer for a record-breaking price in excess of $122 million.