[MITgcm-support] diagnostics parameter

[Jody Klymak]

Hi Martin,

Before Jean-Michel explains it properly:

On Sep 10, 2013, at  9:28 AM, Martin Losch <Martin.Losch at awi.de> wrote:

> Hi there,
> 
> this is a problem that I keep running into, and since the search function on mitgcm.org does not help very much (as usual), I have to ask this question again:
> 
> For debugging reasons, I want the model to start from a pickup at nIter0 = 131544. My timestep is deltaT = 1200. I want the model to write diagnostics at each timestep after timestep 141192, i.e. after the model has reached the time 141192*1200sec = 169430400sec=134days. I thought that I could do it like this in data.diagnostics (<http://mitgcm.org/pipermail/mitgcm-support/2010-August/006799.html>):
> 
>   filename(1) = 'myfile',
>   frequency(1) = 1.,
>   timePhase(1) = 169430400.,
>   fields(1,1) = 'ETAN    ', ….

I think you want frequency(1)=1200.  
I'm pretty sure that timePhase should be less than 1200. i.e. it says where in the 1200s the averaging occurs.  

C     frequency :: Frequency (in s) of Output (ouput every "frequency" second)
C     timePhase :: phase (in s) within the "frequency" period to write output

I am very confused by your math.  141192*1200sec = 169430400sec=1961 days, not 134, and none of your numbers below make sense ;-)

I don't know that there is a way to start writing diagnostics after a certain time w/o restarting to model.

Cheers,   Jody


> because it says in the standard data.diagnostics files in the verification experiments:
> #  timePhase(n)     : write at time = timePhase + multiple of |frequency|
> 
> Obviously I got it wrong because now the model writes output at timesteps 132408 (after 12 days), 134568 (42days), 136800 (73days), etc.
> Where did I go wrong, and how can I do it correctly?
> 
> Analogously in the diag_stats name list, I specified stats_freq=1 and stats_phase=169430400 and got output every time step from the very beginning (so already at time step 131544). Why are the two parameter sets behaving so differently?
> 
> Martin
> 
> 
> 
> 
> 
> _______________________________________________
> MITgcm-support mailing list
> MITgcm-support at mitgcm.org
> http://mitgcm.org/mailman/listinfo/mitgcm-support

--
Jody Klymak    
http://web.uvic.ca/~jklymak/