Hydrometeorological extremes—including extreme rainfall, floods, droughts, and heatwaves—cause hundreds of billions of dollars in economic losses and widespread societal disruption each year. Yet these low-frequency, high-consequence events remain among the hardest to characterize and prepare for, due to: (1) small sample sizes in gauged records; (2) uncertainty in modeling frameworks and data products; and (3) nonstationarity driven by climate change and human activities.

This session invites contributions that advance regional and global hazard and risk assessment of hydrometeorological extremes, with a particular focus on events with return periods beyond 100 years. We welcome submissions include but are not limited to: statistical, process-based, and data-driven approaches; multivariate and compound event analysis; predictions in data-scarce regions; and investigations of the physical mechanisms governing these extremes and their projected changes under future climates.