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

[Dhruv Balwada]

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
>>
>>
>> _______________________________________________
>> MITgcm-support mailing list
>> MITgcm-support at mitgcm.org
>> http://mitgcm.org/mailman/listinfo/mitgcm-support
>>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mitgcm.org/pipermail/mitgcm-support/attachments/20170301/8e37dc14/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: plots_vec_false_test.pdf
Type: application/pdf
Size: 288590 bytes
Desc: not available
URL: <http://mitgcm.org/pipermail/mitgcm-support/attachments/20170301/8e37dc14/attachment-0003.pdf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: plots_vec_true_test.pdf
Type: application/pdf
Size: 268555 bytes
Desc: not available
URL: <http://mitgcm.org/pipermail/mitgcm-support/attachments/20170301/8e37dc14/attachment-0004.pdf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: opt_file.pdf
Type: application/pdf
Size: 19364 bytes
Desc: not available
URL: <http://mitgcm.org/pipermail/mitgcm-support/attachments/20170301/8e37dc14/attachment-0005.pdf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: data
Type: application/octet-stream
Size: 2027 bytes
Desc: not available
URL: <http://mitgcm.org/pipermail/mitgcm-support/attachments/20170301/8e37dc14/attachment-0001.obj>