[MITgcm-support] linear EOS and Tref

[Martin Losch]

I use Tref=1 in all cases (have not tried Tref=3, yet, maybe I 
should?), and I have different initial fields, one is 0.1+random, and 
one is 3+random.

M.

On Aug 25, 2004, at 3:37 PM, Alistair Adcroft wrote:

> When you did 3+0.01*random_noise[0 1] did you use Tref=1 or Tref=3 ?
>
> A.
> --
> Dr Alistair Adcroft            http://www.mit.edu/~adcroft
> MIT Climate Modeling Initiative        tel: (617) 253-5938
> EAPS 54-1624,  77 Massachusetts Ave,  Cambridge,  MA,  USA
>
> -----Original Message-----
> From: mitgcm-support-bounces at mitgcm.org
> [mailto:mitgcm-support-bounces at mitgcm.org] On Behalf Of Martin Losch
> Sent: Wednesday, August 25, 2004 3:49 AM
> To: MITgcm Support
> Subject: [MITgcm-support] linear EOS and Tref
>
>
> Hi,
> I have a puzzle to solve, maybe someone can help:
> I use the linear EOS with a constant Tref = 1 and rhoConst=rhoNil=1035.
> I have an inital temperature of 0.1+0.01*random_noise[0 1]. With a heat
> flux of 200W/m^2 at the surface and non-hydrostatic dynamics I get
> convection after a while, everything is fine, scaling laws seem to be
> good etc.
> Now I repeat the experiment with a different initial temperature of
> 3+0.01*random_noise[0 1]. I thought that this should not change the
> solution (provide that the "random_noise" is the same), because all
> that matters dynamically is the 3D gradient of (T-Tref) which is
> actually independent of Tref. In my case I have T+deltaT-Tref, where
> deltaT=2.9=constant, so effectively I have a different Tref. But
> contrary to my expectations the solution does change and, what is
> particularily bad, the convection regime does not follow general
> scaling laws (e.g. average of w^2 should scale with sqrt(Q/f),etc)
> anymore and the temperature skewness no longer has a smooth vertical
> profile etc. All in all the solution looks weird.
> (BTW,  theta never reaches freezing (-1.8degC).)
>
> Any clue what could be going on?
>
> Martin