Rising Numbers, Rising Risks: Population, Growth, and Natural Disasters

How does population size and growth affect the risk of natural disasters? On October 7, 2024, before Hurricane Milton makes landfall in the Tampa Bay area, Tampa Mayor Jane Castor issues a dire warning to affected citizens: “I can say without any dramatization whatsoever. If you choose to stay in one of those evacuation areas, you’re going to die.” While there is an extensive literature which focuses on the impact of climate change and/or natural disasters, there is a dearth of works on how population affects the risks of natural disasters. As both the frequency and severity of storms and other natural events increase in recent years, it becomes even more imperative that we understand the how human activities contribute climate change and natural disasters. Analyzing county-level data in the United States on the risk of natural disasters from the Federal Emergency Management Agency, we find that both total county population and population change are statistically significant predictors of an area’s risk of natural disasters. Specifically, we show that counties with larger populations and experiencing greater population growth are at higher risks of natural disasters. More broadly, our results contribute to our understanding of population migration dynamics, as well as the long-lasting impacts of natural disasters beyond immediate damages incurred.