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#2068 (Wrong namelist double diffusion mixing parameter name) – NEMO

Opened 5 years ago

Last modified 22 months ago

#2068 assigned Defect

Wrong namelist double diffusion mixing parameter name

Reported by: Robin_Waldman Owned by: gm
Priority: low Milestone: Unscheduled
Component: OCE Version:
Severity: minor Keywords:
Cc:

Description

Context

I am currently checking the activation of the EVD scheme in the case of differential T-S mixing, either due to the double-diffusion mixing parametrization or to the new De Lavergne tidal mixing parametrization. Tests are done with NEMOMED12 configuration in the Mediterranean Sea.

Analysis

  • The double diffusion mixing parametrization has 2 namelist parameters, one of which is wrongly named. rn_hsbfr is actually not the buoyancy flux ratio (constant=0.7 in zdfddm.F90) but the critical density ratio Rc, above which double diffusion rapidly decays.
  • Also, the activation of key_zdftmx_new imposes the activation of the double diffusion mixing parametrization, which is not necessarily desired.

Recommendation

  • Rename rn_hsbfr as rn_cdr for critical density ratio, and if useful introduce a new namelist parameter rn_hsbfr with default value 0.7.
  • Introduce a logical in the namzdf_ddm section to activate or not double diffusion mixing when key_zdfddm is activated.

...

Commit History (0)

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Change History (2)

comment:1 Changed 4 years ago by clevy

  • Owner set to gm
  • Status changed from new to assigned

comment:2 Changed 22 months ago by nemo

  • Milestone set to Unscheduled
  • Version v3.6 deleted
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