[MITgcm-support] Using close boundaries and two layer temp profile in internal wave test

[Abbas Dorostkar]

Hi Jody and others,

Instead of open boundary forcing in internal wave test case, I used free
slip boundaries with a prescribed temperature profile including an
internal Gaussian of depression at the left boundary. This initial temp
is composed of two layers which differ temp by deltaT=20 c, and are
separated by a pycnocline with thickness of delta=10m. Here is the
equation I used:

T(x,z,t=0)= T0-0.5*deltaT*tanh(-2*(z-phi(x,t))*2.64665/delta)

Where, 
phi(x,t)=-phi0-alpha*exp(-x^2/sigma^2), shape of the isopycnal
T0=15 c 
phi0=20m, undisturbed depth of isopycnal
alpha=40m, amplitude of the initial depression
sigma=500m, Guassian half-width

  
I am not sure how to define Tref in the model when t is variable in both
x and z direction so for now I just set TRef to zero (Any ideas how to
define Tref?). 

I just changed following flags: rigidLid=.TRUE., nonHydrostatic=.TRUE.
and Tref=0 

Anyway, after running I got the error message: Stopped due to extreme
values of solution. So, I decreased the time step from 500 s to 100 s
and it works fine but I got velocities equal to zero and there is no
motion at all.
I would be happy if someone can tell me what the problem is.
Thanks,
Abbas

*************************
Abbas Dorostkar, PhD Student
Dept. of Civil Engineering,
Queen's University,
Kingston, ON, Canada
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