Abstract
Results from the new Department of Energy super-parameterized (SP) Energy Exascale Earth System Model (SP-E3SM) are analyzed and compared to the traditionally parameterized E3SMv1 and previous studies using SP models. SP-E3SM is unique in that it utilizes Graphics Processing Unit hardware acceleration, cloud resolving model mean-state acceleration, and reduced radiation to dramatically increase the model throughput and allow decadal experiments at 100-km external resolution. It also differs from other SP models by using a spectral element dynamical core on a cubed-sphere grid and a finer vertical grid with a higher model top. Despite these differences, SP-E3SM generally reproduces the behavior of other SP models. Tropical wave variability is improved relative to E3SM, including the emergence of a Madden-Julian Oscillation and a realistic slowdown of Moist Kelvin Waves. However, the distribution of precipitation exhibits indicates an overly frequent occurrence of rain rates less than 1 mm day-1, and while the timing of diurnal rainfall shows modest improvements the signal is not as coherent as observations. A notable grid imprinting bias is identified in the precipitation field and attributed to a unique feedback associated with the interactions between the explicit cloud resolving model convection and the spectral element grid structure. Spurious zonal mean column water tendencies due to grid imprinting are quantified—while negligible for the conventionally parameterized E3SM, they become large with super-parameterization, approaching 10% of the physical tendencies. The implication is that finding a remedy to grid imprinting will become especially important as spectral element dynamical cores begin to be combined with explicitly resolved convection.
| Original language | English |
|---|---|
| Article number | e2019MS001863 |
| Journal | Journal of Advances in Modeling Earth Systems |
| Volume | 12 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 1 2020 |
Bibliographical note
Publisher Copyright:©2020. The Authors.
Funding
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE‐AC52‐07NA27344. This research used resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE‐AC05‐00OR22725. 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. This research was supported by the Exascale Computing Project (17‐SC‐20‐SC), a collaborative effort of the U.S. Department of Energy Office of Science and the National Nuclear Security Administration. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract DE‐AC02‐05CH11231. The E3SM project, code, simulation configurations, model output, and tools to work with the output are described at the website ( https://e3sm.org ). Instructions on how to get started running E3SM are available at the website ( https://e3sm.org/model/running-e3sm/e3sm-quick-start ). All code for E3SM may be accessed on the GitHub repository ( https://github.com/E3SM-Project/E3SM ). All code for SP‐E3SM may be accessed from a separate GitHub repository ( https://github.com/E3SM-Project/E3SM-ECP ). Model output data are accessible directly from the DOE's National Energy Research Scientific Computing Center (NERSC) or through the DOE Earth System Grid Federation ( https://esgf-node.llnl.gov/projects/e3sm-ecp ). This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This research used resources of the Oak Ridge Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC05-00OR22725. 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. This research was supported by the Exascale Computing Project (17-SC-20-SC), a collaborative effort of the U.S. Department of Energy Office of Science and the National Nuclear Security Administration. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract DE-AC02-05CH11231. The E3SM project, code, simulation configurations, model output, and tools to work with the output are described at the website (https://e3sm.org). Instructions on how to get started running E3SM are available at the website (https://e3sm.org/model/running-e3sm/e3sm-quick-start). All code for E3SM may be accessed on the GitHub repository (https://github.com/E3SM-Project/E3SM). All code for SP-E3SM may be accessed from a separate GitHub repository (https://github.com/E3SM-Project/E3SM-ECP). Model output data are accessible directly from the DOE's National Energy Research Scientific Computing Center (NERSC) or through the DOE Earth System Grid Federation (https://esgf-node.llnl.gov/projects/e3sm-ecp).
| Funders | Funder number |
|---|---|
| DOE Earth System Grid Federation | |
| DOE Office of Science | |
| Office of Biological and Environmental Research | |
| U.S. Department of Energy Office of Science | |
| U.S. Department of Energy | |
| Office of Science | DE‐AC05‐00OR22725 |
| National Nuclear Security Administration | DE‐AC02‐05CH11231 |
| Biological and Environmental Research | 17‐SC‐20‐SC |
| Lawrence Livermore National Laboratory | DE‐AC52‐07NA27344 |