[CIG-LONG] thermal diffusivity scaling and specifying correct temperature profile in hydrostatic term

[Karen Paczkowski]

Hi,

I had a few questions about adding a thermal field to my subduction  
zone model.

1)  On page 16 in the new manual (18 in the old manual) it says that  
the thermal diffusivity needs to be scaled like the velocity and the  
viscosity.  So for a thermal diffusivity of 1E-6 m^2/s and a viscosity  
of 1E21, this should scale the thermal diffusivity to something like  
1E15 when viscosity is rescaled to 1.  The example dike xml file has  
the thermal diffusivity rescaled like this, but the example subduction  
zone program does not have this rescaling.  I was wondering if the  
rescaling should or shouldn't be done?

2)  My simulation currently goes from the earth's surface to a depth  
of 440km.  I have a thermal field given by TemperatureProfile such  
that the temperature goes from 273 K at the top of the simulation to  
1623K at a depth of 100km.  The temperature is then constant below  
100km depth.  I can specify all of the terms for the temperature  
profile (upper density, upper alpha, T_0, height, linearcoefficient,  
etc) but there is nowhere to specify at what depth the temperature  
becomes a constant.  I think my hydrostatic term thinks that my linear  
temperature profile extends down through the whole simulation box.  I  
believe that this is causing large errors in my flow field.  I would  
expect a downward flow driven by the subduction slab (the only forcing  
in the system), but instead I get an upward flow with a magnitude over  
2 orders of magnitude larger than the slab velocity.  How can I  
correctly tell my hydrostatic term what my temperature profile is?

I have attached an input file to the email.  It is currently written  
for Gale 1.4.  I was also wondering where I can find the instructions  
on how to upgrade my xml input files to be run with the new version of  
Gale?

Thank you,
Karen

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