[MITgcm-support] Re: No Subject

[Dimitris Menemenlis]

Hi Armando, I am copying your message to mitgcm-support
list for future reference.

Not an expert on new find_rho, but I have never run into problem
you mention.  Are you setting reference T/S profiles properly and
are you providing a correct POLY3.COEFFS file?

You probably better off updating to, e.g., "eosType='JMD95Z'",
which does not require the POLY3.COEFFS input file.

Not sure I follow the second part of your question.  Isn't this:

KPPdiffKzS = vddiff(...,2) = diffus (imt,2) = scalar = salt/tracer
KPPdiffKzT = vddiff(...,3) = diffus (imt,3) = temperature = temperature

what's in the code?

On a separate note, which vertical mixing parameterization are you
implementing?   I am looking into some issues around Antarctica, too
much vertical mixing for hi-res and not enough for low-res integrations,
so would be interested to know more about your work.

Cheers, Dimitris


> Dear Dr. Menemenlis:
> 
>         My name is Armando Howard and I work on parameterization
> of vertical mixing for OGCMs with V.Canuto, Y.Cheng and M.Dubovikov
> of Goddard Institute for Space Studies. I have recently been trying
> to put our vertical mixing parameterization into the MIT OGCM and
> since I understand you worked on getting the KPP working in this
> OGCM I was hoping you might be able to provide some insight into
> my problems. 
> 
>         I need the density not just at the surface, but on the
> whole column so I tried to retrieve it with
>  1620     DO k = 1,Nr
>          call FIND_RHO(
>      I        bi, bj, ibot, itop, jbot, jtop, K, K, eosType,
>      I        theta, salt,
>      O        RHOK,
>      I        myThid )
>         
> where rhok is a 2 dimensional array for density at the given
> level which I then copy into a three dimensional array. 
> However I find that the rhok being returned is zero. 
> The theta and salt values are not zero and within the ocean
> range and in the "data" file      
>  eosType = 'POLY3',
> I was wondering if from your greater experience you perhaps
> had a guess as to what my problem might be.
> 
> I also have a question about the correspondence between the
> diffusivities in the KPP code and the larger model.
> 
> In kpp_calc you set 
> 
>          KPPviscAz(i,j,k,bi,bj) = vddiff(i,j,k-1,1) * pMask(i,j,k,bi,bj)
>          KPPdiffKzS(i,j,k,bi,bj)= vddiff(i,j,k-1,2) * pMask(i,j,k,bi,bj)
>          KPPdiffKzT(i,j,k,bi,bj)= vddiff(i,j,k-1,3) * pMask(i,j,k,bi,bj)
> 
> and vddiff is an output from KPPMIX, which is called diffus in the 
> kppmix subroutine itself. However there diffus(imt,2) is referred to
> as scalar diffusivity while diffus(imt,3) is referred to as temperature
> diffusivity. But in kpp_calc KPPdiffKzT is, appropriately to its name,
> referred to as temperature diffusivity and KPPdiffKzS is referred to
> as salt and tracer diffusivity. Taking "salt and tracer" to be "scalar"
> it seems to me that 2 and 3 are switched in the definition in 
> KPPMIX:
> c     diffus (imt,1)  - vertical viscosity coefficient                  (m^2/s)
> c     diffus (imt,2)  - vertical scalar diffusivity                     (m^2/s)
> c     diffus (imt,3)  - vertical temperature diffusivity                (m^2/s)
> 
> 
> Am I missing something?
> 
> Thank you for any help you can provide.
> 
> Armando Howard

-- 
Dimitris Menemenlis <menemenlis at jpl.nasa.gov>
Jet Propulsion Lab, California Insitute of Technology
MS 300-323, 4800 Oak Grove Dr, Pasadena CA 91109-8099
tel: 818-354-1656;  fax: 818-393-6720