Version 4 (modified by laurent, 13 months ago) (diff)

ASINTER-05_Brodeau_Advanced_Bulk

Last edition: 12/06/19 11:32:15 by laurent

The PI is responsible to closely follow the progress of the action, and especially to contact NEMO project manager if the delay on preview (or review) are longer than the 2 weeks expected.

  1. Summary
  2. Preview
  3. Tests
  4. Review

Summary

See ticket #2159 https://forge.ipsl.jussieu.fr/nemo/ticket/2159

Action ASINTER-05_Brodeau_Advanced_Bulk
PI(S) Laurent Brodeau @ Ocean Next

Digest

More accurate air-sea flux estimates through the implementation of a cool-skin/warm-layer parameterization in NEMO, also more advanced bulk formulae over sea-ice.

Dependencies
Expected for
Ticket #2159
Branch NEMO/branches/2019/dev_r11085_ASINTER-05_Brodeau_Advanced_Bulk
Previewer(s)
Reviewer(s)
Link

'.' => '/nemo/wiki/2019WP/ASINTER-05_Brodeau_Advanced_Bulk'

Preview

Modified modules aka source files

(Forked from NEMOGCM trunk at rev 11085)

  • DOM/phycst.F90
    • Moved/merged all physical parameters previously declared into sbcblk.F90 into phycst.F90 (keeping the name they had in phycst.F90 when previously declared in both modules with a different name)
  • SBC/sbc_oce.F90
    • Added tsk, public 2D array to contain the sea-surface skin temperature from the cool-skin/warm-layer parameterization [Celsius]
    • Added rhoa, public 2D array to contain the air density at z=zu [kg/m3]
  • SBC/sbcblk.F90
    • Moved/merged all physical parameters previously declared into sbcblk.F90 into phycst.F90 (keeping the name they had in phycst.F90 when previously declared in both modules with a different name)
    • Moved all the functions for air thermodynamics into a new module: SBC/sbcblk_phy.F90
    • New namelist parameters to namelist's section namsbc_blk:
      • ln_skin
      • ln_humi_dpt
    • Added function FUNCTION sbc_blk_cswl_alloc() to allocate array tsk (declared into sbc_oce.F90).
    • Added part where turb_ecmwf (and soon turb_coare*) is called with Qlw, rad_sw, & slp (optional arguments) in case of ln_skin=.true.
    • 0.98 now becomes rdct_qsat_salt (into phycst.F90)
    • Longwave radiative flux component zqlw now computed after turbulent fluxes are, because needs the updated skin temperature which comes out the turb_ecmwf (and soon turb_coare*) function
    • Corrected mistake: no rdct_qsat_salt factor for q_sat over ice! (zqi_sat)
    • Added XIOS iom_put for density of air (rho_air), and skin temperature
    • Added local arrays zqair to contain specific humidity of air at height rn_zqt
    • When ln_humi_dpt=.true., zqair is deduced from the dew-point temperature (read into sn_humi file) and the SLP. When ln_humi_dpt=.false., zqair is simply what is read into sn_humi file
    • rhoa (air density at height rn_zu, declared into sbc_oce.F90) is updated once for all in blk_oce() instead of being computed their and their in different locations.
  • SBC/sbcblk_algo_ecmwf.F90
    • Increased numerical stability to handle non-realistic values over land points, which caused systematic crash in old version (such as in 4.0) What’s really new:
    • The use of the cool-skin/warm-layer parameterization is triggered when optional arguments Qsw, rad_lw, slp are specified when calling turb_ecmwf
      • In each iteration step, estimation of solar and non-solar components of net surface heat flux is done prior to call to subroutine CSWL_ECMWF (defined into SBC/sbcblk_skin.F90)
    • Some variables renamed for clarity, ex: sst → T_s
    • Function visc_air moved to sbcblk_phy.F90
    • Use of official function Ri_bulk() defined into SBC/sbcblk_skin.F90
  • SBC/sbcblk_algo_coare.F90
    • Increased numerical stability to handle non-realistic values over land points, which caused systematic crash in old version (such as in 4.0) What’s really new:
    • The use of the cool-skin/warm-layer parameterization is triggered when optional arguments Qsw, rad_lw, slp are specified when calling turb_coare
    • In each iteration step, estimation of solar and non-solar components of net surface heat flux is done prior to call to subroutine CSWL_ECMWF (defined into SBC/sbcblk_skin.F90)
    • Some variables renamed for clarity, ex: sst → T_s
    • Function visc_air moved to sbcblk_phy.F90
    • Use of official functions One_on_L() and Ri_bulk() defined into SBC/sbcblk_skin.F90
  • SBC/sbcblk_algo_ncar.F90
    • Bla bla to come…

New modules aka source files

  • SBC/sbcblk_phy.F90 [ catalogue of functions for non constant physical parameters in the MBL (Marine Boundary Layer) ] Gathers the following functions:
    • virt_temp
    • Rho_air
    • Visc_air
    • L_vap
    • cp_air
    • gamma_moist
    • One_on_L
    • Ri_bulk
    • q_sat
  • SBC/sbcblk_skin.F90 [ cool-skin / warm-layer parameterization of ECMWF, countains function CSWL_ECMWF, which updates the value of the skin temperature out of previous guess of skin temperature, solar and non-solar components of surface heat flux and friction velocity u*] Gathers the following subroutine:
    • CSWL_ECMWF

Since the preview step must be completed before the PI starts the coding, the previewer(s) answers are expected to be completed within the two weeks after the PI has sent the request to the previewer(s).
Then an iterative process should take place between PI and previewer(s) in order to find a consensus

Possible bottlenecks:

  • the methodology
  • the flowchart and list of routines to be changed
  • the new list of variables wrt coding rules
  • the summary of updates in literature

Once an agreement has been reached, preview is ended and the PI can start the development into his branch.

Tests

Once the development is done, the PI should complete the tests section below and after ask the reviewers to start their review.

This part should contain the detailed results of SETTE tests (restartability and reproducibility for each of the reference configuration) and detailed results of restartability and reproducibility when the option is activated on specified configurations used for this test

Regular checks:

  • Can this change be shown to produce expected impact (option activated)?
  • Can this change be shown to have a null impact (option not activated)?
  • Results of the required bit comparability tests been run: are there no differences when activating the development?
  • If some differences appear, is reason for the change valid/understood?
  • If some differences appear, is the impact as expected on model configurations?
  • Is this change expected to preserve all diagnostics?
  • If no, is reason for the change valid/understood?
  • Are there significant changes in run time/memory?

Review

A successful review is needed to schedule the merge of this development into the future NEMO release during next Merge Party (usually in November).

Assessments:

  • Is the proposed methodology now implemented?
  • Are the code changes in agreement with the flowchart defined at preview step?
  • Are the code changes in agreement with list of routines and variables as proposed at preview step?
    If, not, are the discrepancies acceptable?
  • Is the in-line documentation accurate and sufficient?
  • Do the code changes comply with NEMO coding standards?
  • Is the development documented with sufficient details for others to understand the impact of the change?
  • Is the project literature (manual, guide, web, …) now updated or completed following the proposed summary in preview section?

Finding:

Is the review fully successful? If not, please indicate what is still missing


Once review is successful, the development must be scheduled for merge during next Merge Party Meeting.