Abstract
Since 1900, landfalling hurricanes have been the costliest of all weather-related disasters to afflict the contiguous United States. To provide a present-day (2022) reevaluation of this risk, this study employs an improved normalization approach to better understand potential economic event losses in the context of contemporary societal conditions. The updated methodology identifies impacted coastal counties using the newly available radius of maximum winds at landfall. Hurricane Katrina is the most expensive hurricane since 1900, with a likely 2022 normalized cost of $234 billion. Combined losses from the 50 most expensive hurricane events are similar to $2.9 trillion in normalized economic losses. The study also explores some "analog storms" where comparisons can be made between two historic storms with similar landfall locations. For example, category 5 Andrew (1992) has lower 2022 normalized losses than category 4 Great Miami (1926), at $125 billion versus $178 billion, most likely due to the significantly different radius of maximum wind size (10 vs 20 n mi; 1 n mi = 1.852 km). As with previous studies, we conclude that increases in inflation, coastal population, regional wealth, and higher replacement costs remain the primary drivers of observed increases in hurricane-related damage. These upsurges are especially impactful for some coastal regions along the U.S. Gulf and Southeast Coasts that have seen exceptionally high rates of population/housing growth in comparison to countrywide growth. Exposure growth trends are likely to continue in the future and, independent of any influence of climate change on tropical cyclone behavior, are expected to result in greater hurricane-related damage costs than have been previously observed. SIGNIFICANCE STATEMENT: Normalization takes historical estimates of damage arising from landfalling hurricanes since 1900 and adjusts these to estimate the damage that would be caused if these events were to recur in 2022, given changes in inflation, coastal population, and wealth. Our updated normalization approach improves upon previous methodologies by allowing for greater consistency through time. This updated normalization finds that Hurricane Katrina is the costliest hurricane since 1900, causing an estimated $234 billion if it were to reoccur in 2022.
