Versions Compared

Old Version 4

changes.mady.by.user Katherine Calvin

Saved on

compared with

New Version 5

changes.mady.by.user Katherine Calvin

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

The Design Document page provides a description of the algorithms, implementation and planned testing including unit, verification, validation and performance testing. Please read  Step 1.3 Performance Expectations that explains feature documentation requirements from the performance group point of view. 

...

This design document covers the port of the iESM code (https://github.com/ACME-Climate/iESM) to the E3SM. The modifications in this document are summarized as follows:
  • Include GCAM in the E3SM code base
  • Call the GCAM component as part of the coupler timing scheme
  • Pass information from GCAM to ELM on LULCC
  • Pass information from GCAM to EAM on CO2 emissions
  • Pass information from ELM to GCAM on NPP and HR


Requirements

Requirement: Replicate the iESM science in E3SM 

Date last modified: 
Contributors: Katherine Calvin (Unlicensed)

The iESM links GCAM to CESM, with the coupling primarily focused on the carbon cycle. Fossil fuel & industrial CO2 emissions AND land use/land cover change are passed from GCAM to the Earth System. Net primary productivity and heterotrophic respiration are passed back to GCAM from the land model. The exchange of information occurs every five years (the native GCAM time step). Data is aggregated/disaggregated between models (GCAM operates at regional scale and 5-year time steps; the ESM operates on a grid with 30 minute time step). Code is documented in Collins et al. (2015); a science example is provided in Thornton et al. (2017). The full iESM repository is available at: https://github.com/E3SM-Project/iESM

Collins, W. D., A. P. Craig, J. E. Truesdale, A. V. Di Vittorio, A. D. Jones, B. Bond-Lamberty, K. V. Calvin, J. A. Edmonds, S. H. Kim, A. M. Thomson, P. Patel, Y. Zhou, J. Mao, X. Shi, P. E. Thornton, L. P. Chini and G. C. Hurtt (2015). "The integrated Earth system model version 1: formulation and functionality." Geosci. Model Dev. 8(7): 2203-2219.

Thornton, P. E., K. Calvin, A. D. Jones, A. V. D. Vittorio, B. Bond-Lamberty, L. Chini, X. Shi, J. Mao, W. D. Collins, J. Edmonds, A. Thomson, J. Truesdale, A. Craig, M. L. Branstetter and G. Hurtt (2017). "Biospheric feedback effects in a synchronously coupled model of human and Earth systems." Nature Clim. Change 7: 496-500.

Requirement: Ensure that all possible configurations of E3SM & GCAM can run

Date last modified:  

Contributors: Katherine Calvin (Unlicensed)

GCAM is an option that we will only need for some simulations. Additionally, we may want to run GCAM-ELM or GCAM-EAM, in addition to GCAM with the fully coupled model. We need to ensure that GCAM can be turned on and off like other components of E3SM through the definition of compsets.


Requirement: Ensure the GCAM couplings can be turned on and off

Date last modified: 

Contributors: Katherine Calvin (Unlicensed)

We will need to be able to flexibly control which information is passed between GCAM and E3SM so that we can quantify the effect of these couplings. We need to ensure that the information passed to GCAM can be controlled via compsets or namelists.

Requirement: Implement the GCAM-E3SM coupling in a manner that can be extended in the future

Date last modified: 

Contributors: Katherine Calvin (Unlicensed)

The phase 2 proposal includes extensions to the coupling between E3SM and GCAM. Additionally, GCAM is continually developing and we need to ensure we can incorporate those changes. Specifically, we will want to be able to adapt the coupling time step, the regional mappings, and which variables are passed. We need to ensure that the system is flexible and extensible.

Algorithmic Formulations, and Design Implementation



Design Solution: Port the iESM coupling code to E3SM and Link GCAM to E3SM via the coupler

Date last modified: 

13


Contributors: Tim Shippert (Unlicensed)

  1. Coupler modifications
    1. cesm_comp_mod.F90
      1. Set up iac vars,  comp type, etc.
      2. modify general component function calls to include iac component
        1. … list function calls
        2. prep_lnd_init
        3. prep_atm_init
      1. RECV/run/SEND sections for iac component
      2. modify general component function calls to include iac component
        1. … list function calls
      1. Header: include iac modules and vars
      2. Mod cesm_init() function
      3. Mod cesm_run() function
    2. prep_lnd_mod.F90
      1. prep_lnd_calc_z2x_lx() - iac export to lnd grid, run in lnd prep
      2. prep_lnd_get_z2x_lx() - accessor function
      3. Mapping functions?
      1. prep_lnd_init() - include iac
      1. New functions
      2. Modify existing functions
    3. prep_atm_mod.
.description.....

.....reference.....

Design Solution: Link GCAM to E3SM via the coupler

Date last modified: 
Contributors: 

.....description.....

.....reference.....
    1. F90
      1. prep_atm_calc_z2x_ax() - iac export to atm grid, run in atm prep
      2. prep_atm_get_z2x_ax() - accessor
      3. Mapping functions?
      1. prep_atm_init() - include iac
      1. New functions
      2. Modify existing functions
    1. ...Files currently unknown
    2. ...list modifications
    1. prep_iac_mod.F90
      1. prep_iac_init()
      2. prep_iac_accum() - accum land inputs, run in lnd post
      3. prep_iac_accum_avg() - average lnd accumulators
      4. prep_iac_calc_l2x_zx()  - lnd export to iac grid
      5. prep_iac_mrg() - merge iac inputs
      1. New functions:
      2. Associated New functions
    1. Modified files
    2. Modify mod files to include iac in function files
    3. New files
  2. New iac coupler interface
    1. iac_comp_mct.F90
      1. iac_init_mct()
      2. iac_run_mct()
      3. iac_final_mct()
      1. New functions
    2. New files
  3. Initialization and communications: modify modules and functions to include iac interface variables and perform iac initializations
    1. IACID, ALLIACID, CPLALLIACID, CPLIACID, numinst_iac
    2. Modify functions to work with iac
    1. seq_infodata_getData, seq_infodata_putData, seq_infodata_init, other functions
      1. iac_present, iac_prognostic, iac_phase, others
      2. explicit and/or bytype interface?
    2. seq_comm_mct.F90
    3. seq_infodata_mod.F90 - add iac
  4. Modifications to lnd and atm components
    1. Code modifications to use CO2 feedbacks from GCAM
      1. ...files and functions currently unknown
  5. Modifications to GCAM code
    1. Modify code to interact with iac/cpl interface


Design Solution: Enable couplings through namelist options

Date last modified: 

 


Contributors: 

.....description.....

.....reference.....


Design Solution: Embed algorithms for temporal & spatial resolution changes within the IAC component that are as flexible as possible

Date last modified: 

 


Contributors: 

.....description.....

.....reference.....

 

Planned Verification and Unit Testing 

Verification and Unit Testing: Expert Review

Date last modified: 
Contributors: 

The named experts provided extensive review of each other's work, to verify that the design and implementations met the stated requirements. Model testing at each stage of implementation was used to verify that intended changes were correctly implemented, and that unintended changes were avoided.


Planned Validation Testing 

Validation Testing:  Evaluation with iESM developed diagnostic scripts

Date last modified:  
Contributors: Katherine Calvin (Unlicensed), Alan Di Vittorio

The results of the ported code will be analyzed in a similar manner to that of the iESM (e.g., Thornton et al., 2017). We will not expect exact matches, since we are using a different ESM, but we can ensure the behavior matches expectations/previous experience.

Planned Performance Testing 

Performance Testing: Short simulations on multiple platforms

Date last modified: 

 


Contributors: Katherine Calvin (Unlicensed)

We do not expect GCAM to alter the performance of the coupled system, but we will perform short coupled simulations on multiple platforms to quantify the change.