[MITgcm-support] serveral questions...

[Jean-Michel Campin]

Hi David,

On Mon, Feb 27, 2006 at 12:39:05PM -0500, David Wang wrote:
> Hello all,
> 
> i've got a couple of questions to ask:
> 
> 1. the diagnostics quantity Tendency of Potential Temperature is denoted 
> as 'TOTTEND ' in diagnostics_main_init.F and as 'TOTTTEND' in 
> diagnostics_fill_state.F. one of them is a typo?

Thanks for pointing this typo. Should be fixed now.

> 2. i'm not quite sure how the newly implemented regional statistics 
> diagnostics works. the example namelist 
> ./verification/aim.5l_cs/input.thSI/data.diagnostics isn't very clear to 
> me. for instance, if i want to trace the evolution of the surface layer 
> temperature averaged over the nino3 region, how?

This "regional statistics diagnostics" has been recently added,
and I did few tests to check that it works properly, but the 
way the regions are defined is not "user friendly" and need some 
improvement (and also some documentation).

In short, to define the regions, you need to generate a file 
(diagSt_regMaskFile=) 
with the region-mask (for now, 1 file only, for all the regions), 
that cover the whole domain and could have several sets of regions 
(= 3rd dimension of the region-mask = nSetRegMskFile). 
The idea is that when several regions have no intersection, 
they can fit on the same mask; when 2 regions overlap, they need to 
go to 2 different sets of regions.
The region "n" is then identified with the region-set number 
(=set_regMask(n), integer) and the value of the mask that corresponds 
to this region (=val_regMask(n), real).

you can find a simple example of a small matlab script "mk3regions_mask.m" in
verification/aim.5l_cs/input.thSI that was used to generate the region-mask 
file: regMask_lat24.bin (with only 1 set of 3 regions).

If you have some problems in using this region stat-diags, please
tell us.

> 3. to restart the model w/ a different time step: the original run ended 
> with a permanent pickup (say, pickup.0000001440.*.data). and i restarted 
> the model w/ a doubled deltaT but the model told me it was looking for 
> pickup.0000000720.*.data. btw i used the startTime/endTime pair in data.
> 

There are several ways to do it, but the simplest might just be
to rename the pickup-file: pickup*.0000001440.* -> pickup*.0000000720.*
(or to specify nIter0=1440, instead of startTime= ..., but this will 
affect your simulated time, unless you change also "baseTime=" )

Jean-Michel