Sea level much higher than assumed in most coastal hazard assessments
Summary
Nature reports that most coastal hazard assessments misrepresent coastal sea level by using geoid surfaces instead of actual mean sea level, leading to systematic underestimations. Through meta-analyses of 385 studies, the authors show that correcting to mean dynamic topography (MDT) increases exposed land and population estimates, with regional hotspots in Southeast Asia; they also provide ready-to-use MDT-referenced DEMs and propose standards to improve reproducibility and policy relevance.