E3SM Versions Save

First release of version 3.0 of the Energy Exascale Earth System Model

Default grid configuration for the low-resolution configuration of v3 is a “trigrid” consisting of

• Atmosphere on ne30pg2 (physics grid). Same as v2.
• Ocean, sea-ice on new Icosahedral 30 km mesh with Ice Shelf Cavities (IcoswISC30E3r5). New in v3
• Land and river run-off on a common 1/2 deg lat-lon grid (r05). New default in v3.

The following compsets are supported at the low-resolution detailed above: F1850, F1950, F2010, F20TR, WCYCL1850, WCYCL1950, and WCYCL20TR

The atmospheric component remains EAM. Its vertical resolution has been increased from 72 layers in version 2 to 80 layers in version 3. Atmospheric physics have had significant additions and changes since version 2:

• Added interactive gas chemistry in stratosphere and troposphere with 32 transported species - the UCI chemistry mechanism
• Update from MAM4 to MAM5. Additional size mode for prognostic treatment of stratospheric sulfate aerosol from explosive volcanic eruptions
• Added explicit representation of secondary organic aerosols (SOA) sources from multigenerational chemical oxidation of biogenic, anthropogenic, biomass burning volatile organic compounds and chemical sinks including photolysis and fragmentation
• Improved aerosol wet removal processes to reduce the overestimation of aerosols and thus aerosol forcing
• Improved numerical coupling of aerosol emission, vertical mixing and dry deposition
• Re-tuned Dimethyl sulfide (DMS) emission, number of monolayers for black carbon (BC) aging, and hygroscopicity of particulate organic matter (kPOM) to improve the representation of aerosol direct forcing.
• Added a new dust emission scheme to enable the time-varying soil erodibility for dust mobilization and to include high-latitude dust sources
• Added Predicted Particle Properties (P3) for stratiform clouds to improve representation of ice microphysical processes and aerosol-cloud interactions
• Added sophisticated cloud microphysics for convective clouds, which allows aerosols to impact convective processes through convective microphysics
• Added Multiscale Coherent Structures Parameterization (MCSP) to represent the effects of organized mesoscale convective systems
• Made cloud base mass flux adjustment in the ZM deep convection based on large-scale dynamics to incorporate the influence of large-scale circulation on deep convection
• Refined lower stratospheric vertical grid and surrogate-accelerated parameter optimization that leads to a considerable improvement of simulation of Quasi Biennial Oscillation (QBO)
• Revised surface gustiness formulation for coupling with land and ocean.
• Adopted rougher topography due to improved terrain-following pressure-gradient and hyper-viscosity formulations.
• Added online conditional diagnostic capability for sampling and budget analysis for the purpose of facilitating process-level model evaluation and debugging
• (not on by default) MOSAIC for explicitly representing nitrate and ammonium aerosols and interactions

The EAMxx (aka SCREAM) code is included as an optional atmosphere component in v3. Configurations with EAMxx are not yet supported.

The land component is ELM. The default configuration for ELM has been switched from vegetation leaf area being specified as a static monthly time series for each gridcell based on satellite data (the satellite phenology or SP mode) to a dynamic vegetation growth model that predicts leaf area dynamics and vegetation height in each plant functional type for each gridcell, and how those change over seasons and years in response to the simulated climate. This implementation uses prognostic coupled carbon, nitrogen, and phosphorus cycles (C-N-P) for vegetation and soil biogeochemistry. It uses the relative demand (RD) approach to resolve competition between plants and soil microbes for available nutrients. It uses the converging trophic cascade (CTC) model for organization of plant litter and soil organic matter pools. The model also includes:

• A computationally efficient radiative transfer parameterization (TOP), which is based on the Monte Carlo simulations, accounts for subgrid topographic effects on solar radiation.
• Changed the order of sublimation and dew on snow depth calculation to ensure that snow depth is not accidentally set to a negative value.
• Updated stomatal resistance to properly account for sunlit or shaded conditions
• New infiltration scheme (off by default)
• New Flow of Agricultural Nitrogen scheme (off by default)

The river model is still MOSART. An optional sediment scheme has been added

The ocean component remains MPAS-Ocean. Major change since version 2.1 include:

• Switched from coupling the mid-layer bottom level pressure of EAM to MPAS-Ocean to using extrapolated pressure at mean sea level, thereby greatly reducing bias in coastal sea surface height and the associated dynamic gradient term for sea ice.
• Switched to a global equal area 30km ocean-sea ice mesh including Antarctic ice shelf cavities.
• Improvements to the Redi isopycnal mixing scheme.
• Improved computational efficiency of the ocean component by changing the baroclinic time stepping method

The sea-ice component, MPAS-Seaice, has had many improvements since 2.1:

• Implemented the CICE Consortium’s Icepack as the default sea ice column physics, including a floe size distribution (off by default). The old column physics (colpkg) remains in the code temporarily while Icepack’s biogeochemistry is being updated, but is not being maintained.
  • Additional BFB changes in the Icepack implementation: a) refactored code to enable bit-for-bit global sums in log output for different decompositions and processor counts; b) added a shortwave redistribution option including sw_redist, sw_frac, and sw_dtemp namelist; c) updated sensible and latent heat bulk formula options set by atmbndy_in. Valid values are similarity (default), mixed, and constant (BFB).
  • Other Icepack changes are BFB except in rare instances that they are intended to fix: a) Moved shortwave absorbed in negligible snow layers to surface; b) added abort in ITD for rare case where (hicen_init(n+1) - hicen_init(n)) <= 0 ; c) modified error tolerance for rare mushy thermo failure.
• Switched to high-frequency sea ice coupling as the default surface stress flux option for all meshes.
• Reduced the maximum number of sea ice atmospheric turbulent flux iterations from 10 to 5.
• Decreased the dynamics minimum concentration sea ice cutoff from 10-3 to 10-11 and the ice mass per unit area cutoff from 10-2 to 10-10.
• Multiple non-BFB bug fixes were made to the code, including a) an erroneous velocity component used for high-frequency atmospheric flux coupling; b) a floating-point exception in MPAS-SI incremental remap code; c) errors in the 5-band delta-Eddington radiation scheme; d) order of operations in albedo calculations for restart consistency; e) thin ice/snow treatment of enthalpy; f) snow interactions with ponds; g) missing snow melt in the melts array; h) undefined meltsliq values; i) initializations for snow mass, biogeochemistry, aerosols, and zsalinity; j) erroneous divisions by aice in the old aerosol scheme (tr_aero); k) call locations of frzmlt_bottom_lateral and neutral_drag_coeffs.
• Reduced standard monthly sea ice output by removing sea ice age, first year ice tracers, and level ice volume and area.
• Added or updated checks on configuration settings. Checks on values necessary for coupled runs are executed in mpas_seaice_initialize.F, and consistency checks for icepack are in mpas_seaice_icepack.F. Consistency checks for colpkg were not updated. Among others, the changes a) removed config_couple_biogeochemistry_fields (not used); and b) renamed seaice_check_constants to seaice_check_constants_coupled.
• Removed ingestion of atmospheric pressure in sea ice coupling fields (not used).

The land-ice component remains MPAS-Albany-landIce (MALI). The version of MALI has been updated to include higher-order advection and time integration. The land-ice component is not yet supported in production configurations with v3.

Version 3 of E3SM includes as an optional wave model, WAVEWATCH III. This option is not yet supported in any production simulations.

• A global unstructured waves mesh with 225km resolution in the open ocean and refinement to match the ocean resolution at coastlines.
• Spectral resolution options use 50, 36 (default), or 25 frequencies (all with 36 directions).
• An unresolved obstacle source term improves significant wave height accuracy by accounting for dissipation due to subgrid scale islands.
• The wave mesh uses a rotated pole coordinate system to avoid the north pole singularity, allowing for complete coverage of the Arctic. A basic damping scheme for waves in sea ice is used for the time being.
• The wave model couples with the ocean to provide a Langmuir mixing enhancement factor via the Stokes drift induced by waves.
• WAVEWATCH III is currently only available when using the V2 low resolution ocean mesh, but not yet for the current V3 low resolution Icos30 ocean configuration.

The coupler remains cpl7/MCT.

• A new property-preserving map procedure enables high-order flux maps between components for selected fields. In v3 low-resolution cases, applied to all atmosphere-to-surface fluxes except precip.
• The calculation of gustiness between atmosphere, ocean and land was rationalized. Gustiness is off for sea ice.

The test suites were updated to support one ultra-low resolution: ne4pg2 with oQU480. ne11 and oQU240 are no longer tested. All tests with productions resolutions now use the v3 low resolution. The build system now follows CMake conventions more closely.

Default processor layouts for the low resolution configuration are available on Perlmutter and other DOE platofrms.

First release of version 2.1 of the Energy Exascale Earth System Model.

The atmosphere component remains EAM. There are no major changes in the default configuration since 2.0. New features include: A semi-lagrangian tracer transport for theta-l dycore, a new algorithm for finding the tropopause, new RRM mesh configurations. Add and update SSP370 and SSP585 cases. Restore the FIDEAL case.

The land component is ELM. There are no major changes in the default configuration since 2.0. Several option features have been added including: implementation of topography-based subgrid structure (topounits) and accompanying parameterizations and atmospheric forcing downscaling methods; a new plant hydraulics scheme; two-way land-river hydrological coupling through the infiltration of floodplain water; an implementation of perennial crops; updates to the SNICAR-AD snow radiative transfer model; and implementation of soil erosion and sediment yield in ELM-Erosion. Each of these new changes is modular in design and can be turned on or off as the user specifies; they are currently being tested in different “BGC” configurations.

The ocean component remains MPAS-Ocean. Major change since version 2.0 include the addition of the Fox-Kemper et al. 2011 parameterization for submesocale eddies, a correction for barotropic thickness consistency that reduces divergence noise, and the addition of an ocean carbon conservation analysis member.

The sea-ice component remains MPAS-Seaice. Major changes since version 2.0 include: A correction to how shortwave parameters are interpolated in the snicar-ad 5-band radiation scheme, the addition of a sea ice carbon conservation analysis member, updates to the default sea ice biogeochemistry namelist parameters to be consistent with version 2.0 improvements to nitrogen cycling and a correction in the ice-ocean dissolved organic nitrogen coupling.

The land-ice component remains MPAS-Albany-landIce (MALI). Major changes since 2.0 include an update to the MALI version and the Greenland mesh.

The river model is MOSART. There are no major changes in the default configuration since 2.0. A major new optional feature is two-way river-ocean hydrological coupling between MOSART and MPAS-O. This change can be turned on or off as the user specifies, and is being tested in different configurations.

The coupler remains cpl7/MCT. Major changes since version 2.0 include: Carbon budget calculated when heat/water budgets active. Fix a bug in land-atm fluxes for tri-grid configurations.

Other: a small bug in the zenith angle calculation was fixed in the data models.

Changes since v2.0.1

Important changes: Add and update SSP370 and SSP585 cases, add tests, fix use-case files, Change ocean and sea-ice IC for ARRM60to10.

EAM: allow thetaxx as a CAM_TARGET, enable northamericax4v1pg2_WC14to60E2r3 for AMIP, fix ndrop initialization, allow up to 15 history files.

EAMxx: allow use of readnl

EAM-MMF: allow transient SST case for C++ MMF, remove specific task/thread count for ESMT test, modify the variance transport diagnostic, reorg tests,

HOMME: Allow optional sponge layer.

ELM: add 2 land-atm compsets, update FATES to API 17.0.0, allow FATES sp mode, allow ELM harvest to drive FATES harvest, fix memleaks, reduce test build times, modified parameters for miscanthus and switchgrass based on calibration

MPAS-Ocean: turn on ocean BGC in BGC cases, fix interface locations for 60L PHC grid, add mode spec to conservation check streams, allow oRRS18to6v3 grid to run with JRA, update ocean and sea ice ICs for ARRM60to10 (needed for v2), GPU port of thickness tendency, add CMPASO-JRA1p4,

MPAS framework: Add new reproducible global sum module for MPAS components, Add mostRecentAccessTime attribute to streams

MPAS-landice: Update MALI version and Greenland mesh

MPAS-seaice: add single-cell test case, fix BGC restart, Adds omp critical directives for ice warnings seen on cori.

CIME: Fix component namelist creation bugs when NINST>1, add OpenACC, OpenMP and CXX GPU tests, fix nonBFB tests, stop using config_compilers, reduce ELM test build times with shared executable, update OpenMPI on Chrysalis. fix baseline handling, provenance handling with update to cime6.0.33, also use component-specific config_pes files and add the ones from master

Machine updates: cori modules after maint, Chrysalis to OpenMPI-4.1.3

run_e3sm: replace default case name and group.

Externals: update SCORPIO to 1.3.2

Changes since v2.0.0

Important change: Fix ocean threading bug seen in debug cases on Chrysalis with Intel 20.0.4. Was introduced around time of v2.0.0 tag. Does not change v2.0.0 answers on Chrysalis because those didn't use threading or debugging.

EAM: Add semi-lagrangian tracer transport for theta-l (F90 and C++), add new algorithm for finding tropopause, add DSCREAM to allow v2 and SCREAM settings in same code such as adjust_ps

EAM-MMF: 60L default, allow C++ back end of RRTMGP (EAM too).

EAMxx: add nu-top functionality, fix forcing functor, add ttype9 and dcmip2012 tests 2.1, 2.2, and 3

HOMME: remove obsolete remap algs, option to specify dynamics alg indep of tracer, new sponge layer, add imex tests

ELM: Add topography-based subgrid (topounits), add FATES-ELM Nitro., Phos. and CH4 coupling, add land-use ts for NARRM, add lulc for SSP3 RCP7, Fix nutrient fertilization exp test and carbon isotope flux, Fix xactive lnd dry deposition, add lake water storage option, fix plant hydraulics 2d params, fix carbon budget calc, fix soil nutrient conc. bug, fix mosart dam bug, add test for new ELM, MOSART features, fix bug in O3 dry dep stomatal resistances, fix plant hydraulics restart BFB error, update mkmapdata.

MOSART: fix bug for reading the latitude from an unstructured input file, fix oversat in bubble test.

MPAS-ocean: Add CFC11, CFC12 tracers, add 2D spherical transport tests, fix del4 tracer mixing, add MARBL ocean tracer mixing, modify harmonic analysis options, add GPU port of vmix routines, fix calc of ML-averaged BV freq.

MPAS-seaice: Change extents of initial polar disks for oRRS18to6v3 grid, fix ice BGC with MARBL, update spherical test cases, fix DON coupling, Remove Cf from sea ice constants.

MPAS-landice: add CRYO1850-4xCO2 compset

CIME: add GCP, ANL GCE, Spock, Perlmutter, deprecate config_compilers.xml, fix and clean-up cmake macros, fix slurm bindings, refactor CIME internal testing, cleanup SCORPIO perf data, allow position independent compset naming,

also: update v2 benchmarking suite, extend e3sm_prod with throughput and memory checks

Archived tag for the GMD manuscript on modeling perennial bioenergy crops in E3SM land model (https://gmd.copernicus.org/preprints/gmd-2021-244/ ).

First release of version 2 of the Energy Exascale Earth System Model.

The atmosphere component remains EAM. Major changes since version 1 include: all column-physics parameterizations are computed on a separate grid that has approximately half the number of points of the dynamics grid, a new nonhydrostatic dynamical core (running in hydrostatic mode) with semi-Lagrangian tracer transport, CLUBB updated from v1 to v2, a new convective trigger (dCAPE/ULL) based on the dynamic Convective Available Potential Energy (CAPE) (dCAPE) and the Unrestricted Launch Level (ULL) concepts is used in ZM. minimum cloud droplet number changed, gravity wave drag energy conservation fixed and new tunings used, dust emission size distribution changed to emit more coarse dust particles

The land component is still ELM. Major changes since version 1 include: using SNICAR-AD for radiation in snow to match the sea-ice model and fixing bugs in snow compaction and water state calculation.

The ocean component remains MPAS-ocean. Major change since version 1 include: Redi isopycnal mixing has been updated, tested, and tuned in combination with the Gent-McWilliams parameterization, a sign error was fixed in the 3rd-order flux routines, the mesh used in low-resolution coupled cases was modified and the time steps adjusted, new regionally refined meshes were created, one focused on North America and another on the Southern Ocean, including ice shelf cavities.

The sea-ice component remains MPAS-seaice. Major changes since version 1 include: A new heat- and freshwater-conserving coupling of frazil ice, turning off of SSH filtering, addition of SNICAR-AD and snow grain aging.

The land-ice component remains MPAS-Albany-landIce (MALI) and is a static ice sheet. There is more out-of-the-box support for cryosphere configurations including the new regionally refined configuration around Antarctica with ice shelf cavities.

The river model is MOSART. The half-degree river mesh was redone so it no longer treats Black and Caspian seas as ocean.

The coupler remains cpl7/MCT. Major changes since version 1 include handling of ice shelf melt fluxes (heat / freshwater exchange with the ocean), and data icebergs.

All components allow regional refinement of their meshes and two separate example of refinement, one in and around North America and one around Antarctica and the Southern Ocean, are provided.

v1.2.0 used for v1 Cryosphere Science Campaign

This release is on the maint-1.2 branch which was branched from master on Feb 25, 2019 (7a3e32d6a), and is the code base for the Cryosphere Science Campaign v1 simulations. This includes modified v1 versions of the atmosphere (EAM), land model (ELM), ocean (MPAS-Ocean), sea ice (MPAS-Seaice), and land ice (MALI). A key feature of the E3SM v1 Cryosphere simulations is the inclusion of Antarctic ice shelf cavities in the ocean domain. This allows the calculation of ice shelf basal melt rates, with a static ice shelf geometry. Another distinction between standard E3SM configurations and Cryosphere configurations is the inclusion of prescribed iceberg fluxes (using gridded monthly climatology data from Merino et al 2016). To account for the explicit representation of Antarctic mass fluxes to the ocean through prognostic basal melting and prescribed icebergs, standard representations of runoff from Antarctica, both solid and liquid, are disabled.

Differences from v1.0 DECK simulations include all of those listed in the v1.1.0-beta tag. Additional differences from the v1.1 BGC simulations are listed in the v1.2.0-beta tag.

This is an archive tag for the GMD paper on the O3v2 module (https://doi.org/10.5194/gmd-2020-293).

This version of code is used for the O3v2 simulations in the paper. It enables the O3v2 module on the maint-1.0 branch with the PSC T threshold for ozone depletion as a name list variable.

First release of E3SM v1.1

DO NOT download the .zip or .tar.gz files included here. They do not contain all of the code. Use "git clone --recursive" instead.

This release includes scientifically-validated tunings of the E3SM Land Model (ELM) and E3SM Atmosphere Model (EAM) for coupled simulations with active land, ocean, and sea ice biogeochemistry, for ELM configurations using the CTC approach to representing nutrient competition.

Additional diagnostic variables have been made available as history variables from the ELM, and from the MPAS-Ocean and MPAS-Seaice biogeochemistry modules, in order to improve consistency with the output variable requests of the Coupled Climate Carbon Cycle Model Intercomparison Project (C4MIP), and to support improved analysis of the land, ocean, and sea ice carbon cycles.

The atmosphere models prognostic CO2 code has been updated to enable regridding of anthropogenic CO2 emission files to the E3SMs native spectral element grid. Note that (1) the prognostic CO2 configuration of E3SM has not been scientifically validated, and (2) the regridding of emission files as currently implemented is not mass-conserving and is intended as a temporary workaround. We do not advise using E3SMv1.1 for fully-coupled carbon cycle simulations where mass conservation is critical, but it is suitable for enabling use of the 3D CO2 tracer for diagnostic and testing purposes.

Several bugs found after v1.0 have been fixed in this tag and changes made to default settings, including: EAM: adding limiters to avoid bad extrapolation in RRTMG, fixing an error in the calculation of NIR reflectance that affects cloud fields derived from MODIS simulator. ELM: fixing surface water and lakes, increasing the land field name size, fixing a memory leak in ELM CNStateType, fixing a snow compaction bug that was resulting in sporadic unphysical snow depths, adding a water budget in the land model (and fixing a water conservation error) MPAS-O: preventing thermo energy conservation errors by lowering the permitted surface flux error in the mushy layer picard iteration to 0.9*ferrmax, fixing a small bug in marine BGC, MPAS-SeaIce: Turning off mpas-seaice history files by default MOSART: Replacing the low-res (half-degree) MOSART file

In addition, the budget output has been turned on by default for any fully coupled case, and CIME was modified to remove a bad term from E3SM water budgets. The CCSM_CO2_PPMV is now set correctly in BGC cases. A bugfix for the IEFLX output is included and the timestep for the EC60to30 mesh has been updated. Finally, a number of minor bugfixes and technical improvements have been introduced in the EAM, ELM and MPAS-Ocean models.

Machine updates for cascade, edison, eos, cori are included.

First public release of the Energy Exascale Earth System Model.

DO NOT download the .zip or .tar.gz files included here. They do not contain all of the code. See https://e3sm.org/model/running-e3sm/e3sm-quick-start/ instead.

The E3SM atmosphere model (EAM) is based on the Community Atmosphere Model version 5 (CAM5): the spectral-element (SE) dynamical core was chosen as the default instead of an option, cloud microphysics, shallow convection, and turbulence parameterizations were replaced; the aerosol parameterization was enhanced substantially, and the vertical resolution was more than doubled (30 to 72 levels). The physics parameterizations have been tested and well-tuned for both low- and high-resolution applications, which is important for addressing our v1 water cycle question.

The E3SM land model (ELM) is based on the Community Land Model Version 4.5 (CLM4.5): new options for representing soil hydrology and biogeochemistry were added to enable analysis of structural uncertainty, with important implications to carbon-climate feedbacks for addressing our v1 biogeochemistry question.

E3SM v1 includes new ocean, sea ice, and land ice models, all based on the Model for Prediction Across Scales (MPAS) that uses Spherical Centroidal Voronoi Tessellations (SVTs) for multi-resolution modeling, which is important for addressing our v1 cryosphere question focusing on the Antarctic Ice Sheet. The river transport model is Model for Scale Adaptive River Transport (MOSART), for a physically based representation of riverine processes. MOSART can operate on regular lat/lon grids or using watersheds as the computational units.

For more information see http://e3sm.org