The biogeochemistry (BGC) configuration of the Department of Energy’s Energy Exascale Earth System Model (E3SM)—i.e., model version E3SMv1.1-BGC and related configurations—were released as part of the E3SM contributions to the Coupled Climate-Carbon Cycle Model Intercomparison Project and other projects. E3SMv1.1-BGC simulates historical carbon cycle dynamics, including the loss in carbon associated with land use and land cover change as well as responses of the carbon cycle to changes in climate and prescribed atmospheric CO₂ scenarios. The land biogeochemistry in E3SMv1.1-BGC showed improvements compared to the predecessor model when evaluated against observational benchmarks.

This presentation will provide an overview of current and planned activities and developments in the E3SM project that link land biogeochemistry with atmospheric processes. These activities include:

1. the development of a land-atmosphere-interaction focused configuration with prescribed sea surface temperature and ocean CO₂ fluxes, and its application in historical simulations;
2. the development of a companion software tool, the Greenhouse Gas Diagnostics for Earth System Simulations (GDESS), to facilitate evaluation of simulated atmospheric CO2 concentrations and fluxes with surface, aircraft, and satellite CO₂ observations;
3. evaluation of the impacts of CO2 radiative and biophysical impacts on land-atmosphere interactions in E3SMv1.1-BGC historical simulations, including impacts on the water cycle and ozone dry deposition;
4. current and planned future land-atmosphere biogeochemistry couplings, including couplings with modules for gas-phase atmospheric chemistry and human-Earth system interactions.