Multi‐Century Projections of Dynamic Sea Level Based on an Updated Two‐Layer Emulator

Abstract Projections of dynamic sea level (DSL) are essential for understanding regional sea level change, yet the high computational cost of global climate models limits their use across diverse emissions scenarios and extended multi‐century time horizons. Here we update a DSL emulator, built on fast and slow climate responses to radiative forcing, by update parameter configurations to align with the IPCC AR6 projections. The enhanced emulator produces global‐scale DSL projections through 2300 under five scenarios, ranging from low to very high greenhouse‐gas emissions (SSP1‐2.6, SSP2‐4.5, SSP3‐7.0, SSP5‐8.5) and including an overshoot pathway (SSP5‐3.4‐OS) not assessed in AR6 sea‐level projections. Results indicate widespread DSL rise in the Northern Hemisphere, largest in the North Atlantic, while widespread decline in the Southern Hemisphere. Changes are amplified under higher‐emission scenarios and exhibit a delayed response driven by slow deep‐ocean responses. Under SSP5‐3.4‐OS, DSL evolution approaches SSP1‐2.6 levels during the 23rd century—revealing reversibility under stringent mitigation.