Abstract
Since 1900, landfalling hurricanes have been the costliest of all weather-related disasters to affect the continental United States. To compare economic damages across time we must account for changing societal conditions such as inflation, population growth, wealth accumulation, and demographic changes through a process known as normalization. This study presents an expanded and updated normalization of economic damage estimates for U.S. landfalling hurricanes and tropical storms from 1900 to 2023. It improves upon existing normalization approaches by refining how population and housing exposure are calculated, using a new radius of maximum winds (RMW) methodology employed in Muller et al. (2025) to identify impacted counties, and further developing this by applying a county-level weighting based on the percent coverage of the RMW. The storm dataset is also expanded from the original top 50 to the top 201 costliest landfalling hurricanes and tropical storms, providing a broader historical foundation for analysis. While these updates enhance the exposure component of normalization, they also highlight the absence of vulnerability considerations in previous methodologies. This study presents, for the first time, a vulnerability adjustment that integrates historical changes in building codes and structural resilience into existing normalization frameworks. By employing damage curves and a building capacity index (BCI) for Florida, it quantifies how improvements in construction practices over time affect loss estimates. Applied to 23 Florida landfalling storms, this adjustment demonstrates that enhanced building standards significantly reduce estimated losses for older events. By integrating both exposure and vulnerability refinements, this updated methodology offers a more accurate and realistic assessment of hurricane-related economic losses. The results provide valuable insights for risk assessment, insurance modeling, and climate adaptation planning, particularly as coastal regions continue to grow and face increasing exposure to tropical cyclone hazards.
