How to do NMC method in JEDI-MPAS?

JEDI
1

I am looking for a way to do NMC method in JEDI-MPAS, but I am not sure how to write the namelist. Is there a sample yaml to do NMC method? Do I specify the perturbation files in the ensemble section or some other sections in the yaml? Thanks!

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Hi @jw12,

Thank you for your interest in JEDI-MPAS. The capability asked is not yet supported in the released version of JEDI-MPAS. There are some scripts and sample yaml files in the released code [here], but it is not supported due to the limited resources.

Some specific questions can be still answered as shown in Mpas-jedi be .

BJ

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Hi @byoung-joo ,

I see. Actually I also saw that blog post you mentioned so I thought NMC method is supported. Anyway thank you for the reply.

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Hi @byoung-joo ,

I have one more question then. How do I do static BE in JEDI-MPAS? I followed the documentation and it mentioned that parameters_bumpcov.yaml and 3dvar_bumpcov.yaml are the yaml files for doing static BE, but I got a little confused about the method because in the sample yaml, static BE is calculated from 5 ensemble members at the analysis time. What is the implication of using ensemble members in the calculation of static BE? Thanks!

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  • parameters_bumpcov.yaml in the ctest list generates the static B files, through the generic component of JEDI, BUMP, which is under the SABER repository. From the yaml, it generates the univariate BUMP B files for variables [temperature,spechum, uReconstructZonal, uReconstructMeridional, surface_pressure]. Here, BUMP calculates the B statistics from five ensemble files as an input.

  • 3dvar_bumpcov.yaml executes the variational application with 3dvar cost function using the univariate BUMP B files, which is generated by parameters_bumpcov.yaml

  • Note that the structure of overall B can change, depending on the configuration (and design).

Hope this helps some of your questions. --BJ

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