[MITgcm-support] numerical noise with CFL<0.02

[Antoine Hochet]

Hi all,
I am running a North Atlantic box with thermal forcing only, at 80km
resolution with LLC4320 numerics. I can't understand why I have numerical
noise even though CFL < 0.02
Details of the configuration are below.
Thanks for your help,
Antoine

LLC4320 numerics:
http://wwwcvs.mitgcm.org/viewvc/MITgcm/MITgcm_contrib/llc_hires/llc_4320/input/
http://wwwcvs.mitgcm.org/viewvc/MITgcm/MITgcm_contrib/llc_hires/llc_4320/code/
except for
# rhoConstFresh=999.8,
# viscC4Leith=2.15,
# viscC4Leithd=2.15,
# viscA4GridMax=0.8,
# useAreaViscLength=.TRUE.,
# debuglevel=-1,
# convertFW2Salt=-1.,
# useRealFreshWaterFlux=.TRUE.,
# globalFiles=.TRUE.,
# writeBinaryPrec=32,
# temp_EvPrRn=0.,
# implicSurfPress = 0.6,
# implicDiv2DFlow = 0.6,
# bottomDragQuadratic = 0.0021,
and no KPP and instead:
bottomDragLinear =3.E-4,
viscAz=1.E-3,
viscAh=1.E3,
diffKhT=7.E2,
diffKzT=1.E-4,
ivdc_kappa=100.,
cg2dMaxIters=1000,
cg2dTargetResidual=1.E-13,
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.mitgcm.org/pipermail/mitgcm-support/attachments/20181129/4871f4ed/attachment-0001.html>