Abstract
This paper documents the biogeochemistry configuration of the Energy Exascale Earth System Model (E3SM), E3SMv1.1-BGC. The model simulates historical carbon cycle dynamics, including carbon losses predicted in response to land use and land cover change, and the responses of the carbon cycle to changes in climate. In addition, we introduce several innovations in the treatment of soil nutrient limitation mechanisms, including explicit dependence on phosphorus availability. The suite of simulations described here includes E3SM contributions to the Coupled Climate-Carbon Cycle Model Intercomparison Project and other projects, as well as simulations to explore the impacts of structural uncertainty in representations of nitrogen and phosphorus limitation. We describe the model spin-up and evaluation procedures, provide an overview of results from the simulation campaign, and highlight key features of the simulations. Cumulative warming over the twentieth century is similar to observations, with a midcentury cold bias offset by stronger warming in recent decades. Ocean biomass production and carbon uptake are underpredicted, likely due to biases in ocean transport leading to widespread anoxia and undersupply of nutrients to surface waters. The inclusion of nutrient limitations in the land biogeochemistry results in weaker carbon fertilization and carbon-climate feedbacks than exhibited by other Earth System Models that exclude those limitations. Finally, we compare with an alternative representation of terrestrial biogeochemistry, which differs in structure and in initialization of soil phosphorus. While both configurations agree well with observational benchmarks, they differ significantly in their distribution of carbon among different pools and in the strength of nutrient limitations.
| Original language | English |
|---|---|
| Article number | e2019MS001766 |
| Journal | Journal of Advances in Modeling Earth Systems |
| Volume | 12 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 1 2020 |
Funding
We thank Cortland Johnson for assistance in preparing Figures 1,2 , and 3 . We also thank three anonymous reviewers for their careful comments, which helped to significantly improve the manuscript. This research was supported as part of the Energy Exascale Earth System Model (E3SM) project, funded by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research. Additional support was provided by the Reducing Uncertainties in Biogeochemical Interactions through Synthesis and Computation (RUBISCO) Scientific Focus Area (SFA), which is sponsored by the Regional and Global Model Analysis (RGMA) Program in the Earth and Environmental Systems Sciences Division (EESSD) of the Office of Biological and Environmental Research in the U.S. Department of Energy Office of Science. We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups (listed in the supporting information , Table S1) for producing and making available their model output. For CMIP the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. Simulations described in this work, and most developmental simulations leading up to them, relied on computational resources provided by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract DE‐AC02‐05CH11231. Computing resources were provided through the ASCR Leadership Computing Challenge (ALCC). The remaining developmental simulations used a high‐performance computing cluster provided by the BER Earth System Modeling program and operated by the Laboratory Computing Resource Center at Argonne National Laboratory as well as resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE‐AC05‐00OR22725. The Pacific Northwest National Laboratory (PNNL) is operated for DOE by Battelle Memorial Institute under Contract DE‐AC05‐76RLO1830. Oak Ridge National Laboratory (ORNL) is managed by UT‐Battelle, LLC, for the U.S. Department of Energy under Contract DE‐AC05‐00OR22725. The work at Lawrence Livermore National Laboratory was performed under the auspices of the U.S. Department of Energy under Contract DE‐AC52‐07NA27344. Los Alamos National Laboratory is operated by Triad National Security, LLC, for the National Nuclear Security Administration of U.S. Department of Energy (Contract 89233218CNA000001). We thank Cortland Johnson for assistance in preparing Figures?1,2, and 3. We also thank three anonymous reviewers for their careful comments, which helped to significantly improve the manuscript. This research was supported as part of the Energy Exascale Earth System Model (E3SM) project, funded by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research. Additional support was provided by the Reducing Uncertainties in Biogeochemical Interactions through Synthesis and Computation (RUBISCO) Scientific Focus Area (SFA), which is sponsored by the Regional and Global Model Analysis (RGMA) Program in the Earth and Environmental Systems Sciences Division (EESSD) of the Office of Biological and Environmental Research in the U.S. Department of Energy Office of Science. We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups (listed in the supporting information, Table S1) for producing and making available their model output. For CMIP the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. Simulations described in this work, and most developmental simulations leading up to them, relied on computational resources provided by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract DE-AC02-05CH11231. Computing resources were provided through the ASCR Leadership Computing Challenge (ALCC). The remaining developmental simulations used a high-performance computing cluster provided by the BER Earth System Modeling program and operated by the Laboratory Computing Resource Center at Argonne National Laboratory as well as resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC05-00OR22725. The Pacific Northwest National Laboratory (PNNL) is operated for DOE by Battelle Memorial Institute under Contract DE-AC05-76RLO1830. Oak Ridge National Laboratory (ORNL) is managed by UT-Battelle, LLC, for the U.S. Department of Energy under Contract DE-AC05-00OR22725. The work at Lawrence Livermore National Laboratory was performed under the auspices of the U.S. Department of Energy under Contract DE-AC52-07NA27344. Los Alamos National Laboratory is operated by Triad National Security, LLC, for the National Nuclear Security Administration of U.S. Department of Energy (Contract 89233218CNA000001).
| Funders | Funder number |
|---|---|
| DOE Office of Science | DE-AC02-05CH11231 |
| Laboratory Computing Resource Center | |
| National Energy Research Scientific Computing Center | |
| Office of Biological and Environmental Research | |
| U.S. Department of Energy Office of Science | |
| U.S. Department of Energy | |
| Battelle | DE‐AC05‐76RLO1830 |
| Office of Science | DE‐AC02‐05CH11231 |
| National Nuclear Security Administration | 89233218CNA000001 |
| Biological and Environmental Research | |
| Argonne National Laboratory | DE‐AC05‐00OR22725 |
| Oak Ridge National Laboratory | DE‐AC52‐07NA27344 |
| Laboratory Computing Resource Center | |
| National Energy Research Scientific Computing Center |
Keywords
- E3SM
- carbon cycle
- carbon-climate feedbacks
- coupled carbon-climate cycle model
- nutrient limitation
- phosphorus limitation