According to Bloomberg,

The chart comes from Attom Data Solutions’ natural hazard index, which matches geographic areas to government data on risk of flood, earthquake, tornado, wildfire, hurricane, and hail.

The riskiest 20 percent of U.S. counties have the most homes, the highest average home values, and the greatest price appreciation in recent years. Why? Buyers who pay premiums for ocean views and mountain lookouts may be getting some additional disaster risk as part of the bargain, said Daren Blomquist, senior vice president at Attom. Those kinds of geographical attributes are likely secondary factors in driving price appreciation, though. More importantly, Attom’s list of disaster-prone areas overlaps with engines of economic activity.

This makes sense to me – it is probably just that the big, vibrant U.S. cities are in hurricane and flood prone coastal areas, in fire-prone Mediterranean climates, or both. Climate change is not going to reduce these risks. Having the earthquake risk thrown on top is kind of just bad luck.