"A Multi-Method Approach for Estimating Attributable Sea Level Rise and Extreme Water Levels Worldwide" at AGU 2025
Abstract
This upload supports the poster presentation of "A Multi-Method Approach for Estimating Attributable Sea Level Rise and Extreme Water Levels Worldwide" at the 2025 American Geophysical Union Annual Meeting, on Friday Dec. 19, 2025.Presentation Abstract:Global sea levels continue to rise because of human-caused climate change, driving increases in worldwide coastal flood risks. But rates of sea level rise and extreme water levels exceedances vary considerably around the world, and the anthropogenic contributions to these local and regional increases have not been systematically analyzed. Understanding the human contribution to sea level impacts is critical for local decision-making, loss and damage determinations, legal proceedings, and climate risk communication. In this study we quantify human-caused climate change's contributions to sea level rise and extreme water levels at 461 global tide gauge locations. Using two complementary approaches—a literature- and observation-based sea level budget and an updated semi-empirical model constrained by historical temperature and sea level records—we estimate attributable sea level rise since 1900. We find that human-caused sea level rise is detectable at 95% of sites where the local sea level budget closes. Across these locations, attributable sea level rise is responsible for 69% (51–76%) of the observed daily extreme water level exceedances over 2000–2018. Since the 1970s, the number of days with attributable observed exceedances has nearly tripled. Our findings show a clear, widespread, and intensifying fingerprint of climate change on coastal flood hazards and risks. The multi-method attribution framework developed here provides a foundation for placing attribution estimates on both historical and real-time flooding events.