[MITgcm-support] layers

[Ryan Abernathey]

Mike,

I'm glad you're interested in using the layers package. I'm cc'ing the  
support list so this email can serve as a some form of documentation  
until we write something more formal. The layers package is still in  
development but works well and is very useful in its current state. It  
is mainly lacking documentation / tutorials.

First, you need to edit LAYERS_SIZE.h at compile time to set the  
number of layers (Nlayers) you want to calculate.

Then you need to have a data.layers. Here is the one I use:
&LAYERS_PARM01
  # 20 year averaging
  layers_taveFreq=1261440000.0,
  # no instantaneous output
  layers_diagFreq=0.,
  layers_G=-0.2,0.0,0.2,0.4,0.6,0.8,1.0,1.2,1.4,1.6,1.8,2.0,
	2.2,2.4,2.6,2.8,3.0,3.2,3.4,3.6,3.8,4.0,
	4.2,4.4,4.6,4.8,5.0,5.2,5.4,5.6,5.8,6.0,
	6.2,6.4,6.6,6.8,7.0,7.2,7.4,7.6,7.8,8.0,8.2,
&

The length of layers_G should be Nlayers+1, because layers_G specifies  
the *boundaries* of the layers, in whatever coordinate you use. By  
default, it uses theta as the coordinate for the layers. But you can  
change this to salt by setting LAYER_nb in data.layers. LAYER_nb=2  
means salt, and LAYER_nb=3 means potential density, referenced to the  
model level specified by layers_kref.

I hope this makes sense. Let me know if you have any other questions.

Cheers,
Ryan



On Dec 15, 2011, at 11:04 AM, Michael A. Spall wrote:

> Hi Ryan,
>
> Thanks, that looks like just what I need.  I can re-run the model.
> Can you send me a sample data.layers file, just so I can be sure
> of what the inputs are?
>
> Mike
>
> -- 
> ==================================================
>
> Michael A. Spall
> Senior Scientist
> Department of Physical Oceanography
> W.H.O.I. MS #21
> 360 Woods Hole Road
> Woods Hole, MA   02543
>
> mspall at whoi.edu
> http://www.whoi.edu/science/PO/people/mspall/
>
> (508) 289-3342 (office)
> (508) 457-2181 (fax)
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