Skip to main content
U.S. flag

An official website of the United States government

Publication Date
15 March 2019

The DOE E3SM Coupled Model Version 1: Overview and Evaluation at Standard Resolution

Authors

Author

This work documents the first version of the U.S. Department of Energy (DOE) new Energy Exascale Earth System Model (E3SMv1). We focus on the standard resolution of the fully-coupled physical model designed to address DOE mission-relevant water cycle questions. Its components include atmosphere and land (110km grid spacing), ocean and sea ice (60km in the mid-latitudes and 30km at the equator and poles), and river transport (55km) models. This base configuration will also serve as a foundation for additional configurations exploring higher horizontal resolution as well as augmented capabilities in the form of biogeochemistry and cryosphere configurations. The performance of E3SMv1 is evaluated by means of a standard set of Coupled Model Intercomparison Project Phase 6 Diagnosis, Evaluation, and Characterization of Klima (CMIP6 DECK) simulations consisting of a long pre-industrial control, historical simulations (ensembles of fully coupled and prescribed SSTs) as well as idealized CO$_2$ forcing simulations. The model performs well overall with biases typical of other CMIP-class models, although the simulated Atlantic Meridional Overturning Circulation is weaker than many CMIP-class models. While the E3SMv1 historical ensemble captures the bulk of the observed warming between pre-industrial (1850) and present-day, the trajectory of the warming diverges from observations in the second half of the 20th century with a period of delayed warming followed by an excessive warming trend. Using a two-layer energy balance model, we attribute this divergence to the model's strong aerosol-related effective radiative forcing (ERF$_{\mathrm{ari+aci}}$ = -1.65 W m$^{-2}$) and high equilibrium climate sensitivity (ECS = 5.3 K).

“The Doe E3Sm Coupled Model Version 1: Overview And Evaluation At Standard Resolution”. 2019. Journal Of Advances In Modeling Earth Systems. doi:10.1029/2018ms001603.
Funding Program Area(s)