Global Trends in Mortality Risk Associated with Coastal Flooding

Coastal flooding, which is influenced by sea level rise, storm surge, and tropical cyclones, is a growing threat. Previous studies have documented mortality associated with historical coastal flooding events and developed predictions of mortality risk based on projected sea level rise. This study advances previous work by utilizing an updated model to estimate exposed populations, including new data on more recent events between 2010 and 2020, and examining trends in mortality over time. Primary data sources include the Emergency Events Database (EM-DAT) and the Sea Level Impacts Input Dataset by Elevation, Region, and Scenario (SLIIDERS) model. We used the Modified Mann Kendall (MMK) Trend Test to evaluate trends in exposed populations and mortality associated with coastal flooding. A regression model was built to estimate mortality risk and investigate the influence of country-level variables including Human Development Index (HDI), population, and event frequency. Results from the trend analysis show a statistically significant increase in people exposed to coastal flooding between 1990 and 2020, while there was a decrease in deaths associated with coastal flooding events. Initial results from the regression model suggest mortality risk is reduced in countries with higher populations. This result suggests countries with larger populations may buffer risks in exposed regions. Furthermore, we found a significant negative association between HDI and mortality risk.