[MITgcm-support] Effect of 'vectorInvariantMomentum' flag on first order circulation

Bruno Deremble bruno.deremble at ens.fr
Fri Mar 3 04:50:45 EST 2017 

glad it worked.
It's not really a bug, I think it is just 2 different ways to handle the
boundary conditions (basically, one scheme conserves PV, the other does not).

for those interested, I put the paper here:
http://www.lmd.ens.fr/deremble/pub/corner_jmr.pdf

bruno

On Friday, Mar 03 2017, 05:34:35, Dhruv Balwada <db194 at nyu.edu> wrote:
> Hi Bruno,
>
> Removing the topography made the solutions for the two cases be the same.
> This is crazy interesting, I think I need to understand your paper better.
>
> Best,
> Dhruv
>
>
>
> On Thu, Mar 2, 2017 at 2:09 PM, Dhruv Balwada <db194 at nyu.edu> wrote:
>
>> Hi Bruno,
>>
>> I haven't removed the topography. I will set that up now. I did try to do
>> the run with no-slip and free-slip walls. The solution was the same in
>> both.
>>
>> Best,
>> Dhruv
>>
>> On Thu, Mar 2, 2017 at 2:08 PM, Dhruv Balwada <db194 at nyu.edu> wrote:
>>
>>> Hi Jean-Michel,
>>>
>>> The experiment setup is now available at - https://github.com/dhruvbalw
>>> ada/channel_run_20km
>>>
>>> I am using a version of the MITgcm that I downloaded in the beginning of
>>> February.
>>>
>>> The difference between two runs appears in a matter of 1 year of the run.
>>> I would probably run it for 2-3 years to see it clearly. On the computers
>>> here with 25 cores it took about 1 hour to run. So, its very fast.
>>>
>>> Let me know if you need any other files, and I can add them to the git
>>> directory.
>>>
>>> Thanks,
>>> Dhruv
>>>
>>> On Thu, Mar 2, 2017 at 10:37 AM, Jean-Michel Campin <jmc at mit.edu> wrote:
>>>
>>>> Hi Dhruv,
>>>>
>>>> OK, this is a good start.
>>>> Could you provide me (off the list since there is some strict size limit
>>>> there)
>>>> a complete copy of the set up, including the customized/modified "code"
>>>> directory,
>>>> the input parameter files ( data*, eedata) and the binary input files
>>>> needed
>>>> to run the set-up.
>>>> Also, if you are not using the latest MITgcm code, which version is it ?
>>>>
>>>> And finally, how long would I need to run it to see some significant
>>>> differences
>>>> (this was part of my earlier email, but not clearly expressed).
>>>> May be a pickup file could allow to reduce the length of these tests ?
>>>>
>>>> Cheers,
>>>> Jean-Michel
>>>>
>>>> On Wed, Mar 01, 2017 at 05:47:25PM -0500, Dhruv Balwada wrote:
>>>> > Hi Jean-Michel,
>>>> >
>>>> > I tried the test you suggested by turning off all optimization, and
>>>> nothing
>>>> > changed. Here are the outputs in prints of python notebooks. I have
>>>> also
>>>> > attached the opt and data file. The data file for both runs point to
>>>> the
>>>> > exact same forcing files on the hard drive.
>>>> >
>>>> > Best,
>>>> > Dhruv
>>>> >
>>>> > On Tue, Feb 28, 2017 at 10:27 AM, Dhruv Balwada <db194 at nyu.edu> wrote:
>>>> >
>>>> > > Hello everyone,
>>>> > >
>>>> > > Thanks for the quick responses.
>>>> > >
>>>> > > @ Jean-Michel I will follow your suggestions and report back on them
>>>> soon.
>>>> > >
>>>> > > Best,
>>>> > > Dhruv
>>>> > >
>>>> > >
>>>> > > On Mon, Feb 27, 2017 at 3:56 PM, Jean-Michel Campin <jmc at mit.edu>
>>>> wrote:
>>>> > >
>>>> > >> Hi Dhruv,
>>>> > >>
>>>> > >> It's a strange results. Both pkgs (mom_fluxform and mom_vecinv)
>>>> have been
>>>> > >> tested and used in many different configs, and no significant recent
>>>> > >> changes
>>>> > >> that would be suspicious.
>>>> > >>
>>>> > >> I suggest to try to work on a short test run:
>>>> > >> 1) long enough to detect some significant differences between the 2
>>>> cases:
>>>> > >>   vectorInvariantMomentum=T and = F
>>>> > >> 2) short enough so that the same 2 runs could be repeated with zero
>>>> > >> compiler
>>>> > >>  optimization (-ieee or -devel with many standard optfile).
>>>> > >> And from there, we could work on trying to reproduce the problem on
>>>> > >>  different machine/compiler ... etc.
>>>> > >> Once we are able to reproduce the problem, should not take too long
>>>> to
>>>> > >> fix.
>>>> > >>
>>>> > >> Cheers,
>>>> > >> Jean-Michel
>>>> > >>
>>>> > >> On Thu, Feb 23, 2017 at 02:58:53PM -0500, Dhruv Balwada wrote:
>>>> > >> > Hi MITgcm community,
>>>> > >> >
>>>> > >> > I have recently been stumped an issue with the MITgcm
>>>> > >> vectorInvariantMomentum
>>>> > >> > flag.
>>>> > >> >
>>>> > >> > **The model setup** is meant to be an ideal representation of the
>>>> ACC
>>>> > >> > (following Abernathey and Cessi 2014). It has the following
>>>> components -
>>>> > >> > a) Linear temperature relaxation at the surface
>>>> > >> > b) Zonal wind with sinusoidal structure
>>>> > >> > c) Initial temp field is zonally symmetric and the thermocline
>>>> shoals
>>>> > >> from
>>>> > >> > north to south (similar to the ACC).
>>>> > >> > d) Resolution is 20km, and domain size is 2000km * 2000km.
>>>> > >> > e) Zonally periodic and meridional walls
>>>> > >> > f) A zonal gaussian bump is the topographic feature, which is
>>>> > >> meridionaly
>>>> > >> > independent.
>>>> > >> >
>>>> > >> > **The issue** I am facing is that the circulation pattern
>>>> completely
>>>> > >> > changes when I change the "vectorInvariantMomentum" flag.
>>>> > >> > When the flag is set to false (default), the model recreates an
>>>> ACC like
>>>> > >> > flow. Flow is from west to east and strongly perturbed by the
>>>> presence
>>>> > >> of
>>>> > >> > topography.
>>>> > >> > When the flag is set to true (default), the model does something
>>>> else.
>>>> > >> Flow
>>>> > >> > is from east to west, with a strong boundary flow from the west
>>>> to east
>>>> > >> > near the southern boundary.
>>>> > >> >
>>>> > >> > Any help would be appreciated.
>>>> > >> >
>>>> > >> > I have posted some visualizations and data file here -
>>>> > >> > https://sites.google.com/site/dhruvbalwada/blog/mitgcmissuew
>>>> > >> ithvectorinvariantmomentumflag
>>>> > >> >
>>>> > >> > Here is the data file (obviously the vectorinvariantmomentum flag
>>>> is
>>>> > >> > changed between two runs.
>>>> > >> >
>>>> > >> >  &PARM01
>>>> > >> >
>>>> > >> > # viscosity
>>>> > >> >
>>>> > >> >  viscAr=5.6614E-04,
>>>> > >> >
>>>> > >> >  viscC4Leith=2.15,
>>>> > >> >
>>>> > >> >  viscC4Leithd=2.15,
>>>> > >> >
>>>> > >> >  viscA4GridMax=0.8,
>>>> > >> >
>>>> > >> >  useAreaViscLength=.TRUE.,
>>>> > >> >
>>>> > >> >  highOrderVorticity=.TRUE.,
>>>> > >> >
>>>> > >> > # diffusivity
>>>> > >> >
>>>> > >> >  tempAdvScheme=7,
>>>> > >> >
>>>> > >> >  diffKrT=5.44e-7,
>>>> > >> >
>>>> > >> >  saltStepping=.FALSE.,
>>>> > >> >
>>>> > >> >  staggerTimeStep=.TRUE.,
>>>> > >> >
>>>> > >> > # multiDimAdvection=.TRUE.,
>>>> > >> >
>>>> > >> >  vectorInvariantMomentum=.TRUE.,
>>>> > >> >
>>>> > >> > # initial vertical profiles of T and S
>>>> > >> >
>>>> > >> >  sRef=30*35.0000,
>>>> > >> >
>>>> > >> > # equation of state
>>>> > >> >
>>>> > >> >  eosType='LINEAR',
>>>> > >> >
>>>> > >> >  tAlpha=2.0E-04,
>>>> > >> >
>>>> > >> >  sBeta=0.0,
>>>> > >> >
>>>> > >> > # boundary conditions
>>>> > >> >
>>>> > >> >  no_slip_sides=.FALSE.,
>>>> > >> >
>>>> > >> >  no_slip_bottom=.TRUE.,
>>>> > >> >
>>>> > >> > # bottomDragLinear=1.1E-03,
>>>> > >> >
>>>> > >> >  bottomDragQuadratic=0.0021,
>>>> > >> >
>>>> > >> > # physical parameters
>>>> > >> >
>>>> > >> >  f0=-0.9E-04,
>>>> > >> >
>>>> > >> >  beta=1.0E-11,
>>>> > >> >
>>>> > >> >  gravity=9.81,
>>>> > >> >
>>>> > >> > # implicit diffusion and convective adjustment
>>>> > >> >
>>>> > >> >  implicitDiffusion=.TRUE.,
>>>> > >> >
>>>> > >> >  implicitViscosity=.TRUE.,
>>>> > >> >
>>>> > >> > # exact volume conservation
>>>> > >> >
>>>> > >> >  exactConserv=.TRUE.,
>>>> > >> >
>>>> > >> > # C-V scheme for Coriolis term
>>>> > >> >
>>>> > >> >  useCDscheme=.FALSE.,
>>>> > >> >
>>>> > >> > # partial cells for smooth topography
>>>> > >> >
>>>> > >> >  hFacMin=5.0E-02,
>>>> > >> >
>>>> > >> > # file IO stuff
>>>> > >> >
>>>> > >> >  readBinaryPrec=64,
>>>> > >> >
>>>> > >> >  useSingleCpuIO=.TRUE.,
>>>> > >> >
>>>> > >> >  debugLevel=1,
>>>> > >> >
>>>> > >> >  &
>>>> > >>
>>>> > >> > _______________________________________________
>>>> > >> > MITgcm-support mailing list
>>>> > >> > MITgcm-support at mitgcm.org
>>>> > >> > http://mitgcm.org/mailman/listinfo/mitgcm-support
>>>> > >>
>>>> > >>
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>>>> > >>
>>>> > >
>>>> > >
>>>>
>>>>
>>>>
>>>>
>>>>
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>>
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