Journal Article

Emulating Ocean Dynamic Sea Level by Two‐Layer Pattern Scaling

Yuan, J., & Kopp, R. E.

Published March 2, 2021


As climate warms, sea‐level rise poses a major threat to coastal communities and ecosystems. A key driver of local sea level change is ocean dynamic sea level change, which is associated with changes in ocean density and circulation. The primary tools used to project changes in dynamic sea level are atmosphere‐ocean general circulation models, which are computationally expensive. Here we develop an emulator for dynamic sea level changes that is, built upon a two‐layer energy balance model. Considering both the rapid response of well‐mixed surface layer and the delayed response of the deep ocean to forcing, the emulator facilitates the estimation of probability distributions of future dynamic sea level change under different emission scenarios and the extension of projections beyond the time horizon of available simulations from some atmosphere‐ocean general circulation models. This emulator captures the evolution of dynamic sea level changes in the atmosphere‐ocean general circulation models to which it is tuned, including the non‐linear and non‐stationary relationship between the dynamic sea level and global warming. The emulator thus facilitates the estimation of future local sea‐level changes.