[MITgcm-support] 2D boundary conditions at the poles
Angela Marie Zalucha
azalucha at MIT.EDU
Thu Nov 17 18:58:11 EST 2011
Hi, I'm having trouble having the model not violate CFL with these
conditions, but I will keep trying. Could you though explain what the
boundary conditions at the poles are in the 2D model, or point to
documentation?
Thanks,
Angela
On Sat, 12 Nov 2011, Jean-Michel Campin wrote:
> Hi Angela,
>
> I would propose to try to use Shap_funct=2 (this is the default)
> instead of Shap_funct=4.
> In addition, you could try to specify a time-scale (the default
> is to use the model time-step), the longer it is, the weaker
> is the filtering. You could start for example with 10 times deltaT:
> Shap_Trtau=150.,
> Shap_uvtau=150.,
> (since deltaT=15.)
>
> Cheers,
> Jean-Michel
>
> On Sat, Nov 12, 2011 at 11:47:53AM -0500, Angela Marie Zalucha wrote:
>> A figure of surface pressure (eta + Ro_SeaLevel) vs. latitude is
>> attached. My data file is below.
>>
>> # ====================
>> # | Model parameters |
>> # ====================
>> #
>> # Continuous equation parameters
>> &PARM01
>> tref=48.2417,48.388,48.6109,48.9495,49.4687,50.2756,51.5217,53.239,
>> 55.3375,57.8211,60.7092,64.0167,67.7569,71.9439,76.5962,81.74,
>> 87.413,93.6712,100.6,108.332,117.086,127.225,139.377,154.64,
>> 174.981,203.995,248.46,321.723,453.693,746.463,
>> sRef=30*0.,
>> #viscAr=0.E1,
>> viscAh=0.E6,
>> viscA4=0.E17,
>> no_slip_sides=.FALSE.,
>> no_slip_bottom=.FALSE.,
>> diffKhT=0.E3,
>> diffKrT=0.,
>> diffK4T=0.E17,
>> diffKrS=0.E2,
>> diffKhS=0.E3,
>> diffK4S=0.E17,
>> buoyancyRelation='ATMOSPHERIC',
>> eosType='IDEALGAS',
>> omega=-1.13856E-5,
>> exactConserv=.TRUE.,
>> gravity=0.63,
>> rhonil=1.0,
>> rhoConst=1.0,
>> rigidLid=.FALSE.,
>> uniformLin_PhiSurf=.FALSE.,
>> nonlinFreeSurf=4,
>> select_rStar=2,
>> implicitFreeSurface=.TRUE.,
>> staggerTimeStep=.TRUE.,
>> readBinaryPrec=64,
>> writeBinaryPrec=64,
>> hFacMin=1.0,
>> # vectorInvariantMomentum=.TRUE.,
>> #- not safe to use globalFiles in multi-processors runs; set instead useSingleCpuIO
>> useSingleCpuIO=.TRUE.,
>> atm_Cp = 1043.,
>> atm_Po = 1.4,
>> atm_Cp = 1043.,
>> atm_Po = 1.4,
>> atm_kappa=0.2857142885714,
>> atm_L=253000.,
>> lengthOfDayInSeconds=551893.,
>> # Buie, tholen, and wasserman 1997 albedo
>> # albedoland = 0.5,
>> # albedoice = 0.5,
>> albedoland=0.,
>> albedoice=0.,
>> radcode = 6,
>> lsIsConstant = 0,
>> lsperpetual = 3.141593,
>> eccentricity = 0.251,
>> semimajoraxis = 5.934632E12,
>> lsp = 3.24383404117,
>> axialTilt = 1.05434,
>> solarconstant = 0.864465,
>> tauoo = 2.,
>> # radTimeStep = 21600.,
>> radTimeStep = 15.,
>> lsStart = 2.5688,
>> hstauawarm=22075.7,
>> hstauswarm=22075.7,
>> hstauacold=22075.7,
>> hstauscold=22075.7,
>> emissivityOfIce=1.0,
>> emissivityOfLand=1.0,
>> allowDiurnal=0,
>> betacab=0.05,
>> tauinfcab=0.1,
>> useCaballero=0,
>> referenceTempInFrostEqn=35.,
>> referencePresInFrostEqn=0.3,
>> initemp=110.,
>> gamma0=0.01,
>> &
>>
>> # Elliptic solver parameters
>> &PARM02
>> cg2dMaxIters=600,
>> cg2dTargetResidual=1.E-13,
>> &
>>
>> # Time stepping parameters
>> &PARM03
>> niter0=0,
>> # nTimeSteps=31104000,
>> # nTimeSteps=69465600,
>> nTimeSteps=71539200,
>> #endTime=864000.0,
>> abEps=0.1,
>> deltaT=15.,
>> cAdjFreq=0.,
>> pChkptFreq=466560000.,
>> chkptFreq=0.0,
>> dumpFreq=7776000.,
>> # dumpFreq=2000.,
>> # dumpFreq=518400.,
>> #dumpFreqFast=39750.,
>> #dumpFreqFastStart=5326500.,
>> monitorFreq=7776000.,
>> # monitorFreq=2000.
>> # monitorFreq=50.,
>> taveFreq=0.,
>> #tave_lastiter=1.,
>> #tave_lastiter=1.,
>> &
>>
>> # Gridding parameters
>> &PARM04
>> usingSphericalPolarGrid=.TRUE.,
>> delX=1*2.8125,
>> delY=64*2.8125,
>> delR=0.0244849394,0.0364268333,0.0525751970,0.0746640152,0.1034712424,
>> 0.1382839394,0.1679554545,0.1557584848,0.1340775758,0.1112777273,
>> 0.0898157273,0.0711273182,0.0555934697,0.0431052576,0.0332630455,
>> 0.0256038788,0.0196925909,0.0151563788,0.0116906364,0.0090528773,
>> 0.0070505591,0.0055292258,0.0043596742,0.0034272000,0.0026279697,
>> 0.0018837212,0.0011799030,0.0005905985,0.0002190777,0.0000554814,
>> Ro_SeaLevel=1.4,
>> # don't change rSphere, because tiles are calculated using this number
>> rSphere=1180.E3,
>> ygOrigin=-90.,
>> &
>>
>> # Input datasets
>> &PARM05
>> topoFile='topo.cs.bin',
>> # topoTextFile='plutotopo.txt',
>> &
>>
>>
>>
>>
>>
>> On Sat, 12 Nov 2011, Jean-Michel Campin wrote:
>>
>>> Hi Angela,
>>>
>>> Could you send the complete parameter file "data" ? might be useful
>>> to figure out what is the problem. Also, a plot of Eta function
>>> of latitude would be nice.
>>>
>>> Cheers,
>>> Jean-Michel
>>>
>>> On Thu, Nov 10, 2011 at 06:34:34PM -0500, Angela Marie Zalucha wrote:
>>>> Hi,
>>>>
>>>> I am running the MIT GCM in 2D for the atmosphere (latitue and r*
>>>> coordinates). When I look at eta vs. latitue, I get a very huge
>>>> spike in the second to last gridpoint from the poles. I believe it
>>>> is numerical and not physical. I was wondering what the boundary
>>>> conditions are at the poles and how to explain it.
>>>>
>>>> Here's what I have for the horizontal grid:
>>>> usingSphericalPolarGrid=.TRUE.,
>>>> delX=1*2.8125,
>>>> delY=64*2.8125,
>>>> ygOrigin=-90.,
>>>>
>>>> The pressure is extremely low because this is Pluto!
>>>> Ro_SeaLevel=1.6,
>>>> rSphere=1180.E3,
>>>>
>>>> I have seen that the Shapiro filter can affect numerical spikes in
>>>> eta in other 2D planets, but haven't been able to modify it
>>>> successfully here. Here's my data.shap :
>>>> &SHAP_PARM01
>>>> shap_filt_uvStar=.FALSE.,
>>>> shap_filt_TrStagg=.TRUE.,
>>>> Shap_funct=4,
>>>> nShapT=4,
>>>> nShapUV=4,
>>>>
>>>> Does anybody have any ideas?
>>>>
>>>> Angela
>>>>
>>>>
>>>>
>>>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
>>>> Angela Zalucha, Ph.D.
>>>> Postdoctoral Associate
>>>> Department of Earth, Atmospheric,
>>>> and Planetary Sciences
>>>> Massachusetts Institute of Technology
>>>>
>>>> Office located at Southwest Research Institute
>>>> 1050 Walnut Street, Suite 300
>>>> Boulder, CO 80302
>>>> USA
>>>> (720) 208-7211
>>>>
>>>>
>>>> http://web.mit.edu/azalucha/www/index.html
>>>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> MITgcm-support mailing list
>>>> MITgcm-support at mitgcm.org
>>>> http://mitgcm.org/mailman/listinfo/mitgcm-support
>>>
>>> _______________________________________________
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>>>
>>
>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
>> Angela Zalucha, Ph.D.
>> Postdoctoral Associate
>> Department of Earth, Atmospheric,
>> and Planetary Sciences
>> Massachusetts Institute of Technology
>>
>> Office located at Southwest Research Institute
>> 1050 Walnut Street, Suite 300
>> Boulder, CO 80302
>> USA
>> (720) 208-7211
>>
>>
>> http://web.mit.edu/azalucha/www/index.html
>> _-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
>>
>>
>
>
>> _______________________________________________
>> MITgcm-support mailing list
>> MITgcm-support at mitgcm.org
>> http://mitgcm.org/mailman/listinfo/mitgcm-support
>
>
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>
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
Angela Zalucha, Ph.D.
Postdoctoral Associate
Department of Earth, Atmospheric,
and Planetary Sciences
Massachusetts Institute of Technology
Office located at Southwest Research Institute
1050 Walnut Street, Suite 300
Boulder, CO 80302
USA
(720) 208-7211
http://web.mit.edu/azalucha/www/index.html
_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-
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