Trends in U.S. Atlantic Tropical Cyclone Damage, 1900–2022

Abstract

Abstract A series of papers published since 1998 assert that U.S. tropical cyclone (TC) damage, when “normalized” for individual wealth, population, and inflation, exhibits no increase attributable to anthropogenic global warming (AGW). This result is here questioned for three reasons: 1) The then-year (no demographic or economic adjustments) U.S. TC damage increases 2.5% yr−1 faster than U.S. then-year gross domestic product. This result, which is substantially due to the faster growth of assets in hurricane-prone states, shows that TC impacts on the total U.S. economy double every generation. 2) Fitting of an exponential curve to normalized damage binned by 5-yr “pentads” yields a growth rate of 1.06% yr−1 since 1900, although causes besides AGW may contribute. 3) During the twenty-first century, when the Atlantic multidecadal oscillation (AMO) was in its warm phase, the most damaging U.S. TCs struck at twice the rate of the warm AMO of the twentieth century and 4 times the rate of the entire twentieth century, both warm and cool AMO phases. A key unanswered question is as follows: What will happen when (and if) the AMO returns to its cool phase later in this century? Significance Statement U.S. hurricane damage, normalized for changes in inflation, population, and wealth, increases by approximately 1% yr−1. For 1900–2022, 1% yr−1 is equivalent to a factor of >3 increase, substantially but not entirely, attributable to climate change. The incidence of the most damaging tropical cyclones (TCs) approximately doubled in the twenty-first century compared with climatologically analogous periods of the twentieth century. These results contradict the previously published work that introduced normalization and found zero trend in normalized damage but are consistent with physical reasoning and modeling studies.