[MITgcm-support] Re: Restart after changing deltatT

[Jean-Michel Campin]

Hi Samar,

Thanks for the report.
I fixed "diff_base_multiple.F" and it should be much better now.
But I don't have a good explanation for not having
a dump at the beginning. 
Are you using
#define MINIMAL_TAVE_OUTPUT
in CPP_OPTIONS.h ?

Jean-Michel

On Wed, May 04, 2005 at 01:04:04PM -0400, samar khatiwala wrote:
> Hi Jean-Michel
> 
> I tried setting baseTime as you suggested (it was more attractive than
> the other option of setting both nIter0 and startTime). I get
> unpredictable (at least by me!) results and was wondering if you could
> help me diagnose the problem.
> 
> Details:
> I have a pickup file at iter=3600000 from a run with deltaTClock=43200.
> I now switch to deltaTClock=1200. New data file looks like:
> 
>  nIter0  =3600000,
>  baseTime =151200000000.0,
>  nTimeSteps = 388800,
>  deltaTClock = 1200.0,
> ...
>  pChkptFreq= 466560000.,
>  dumpFreq=   155520000.,
> 
> The baseTime I calculated using your formula:
>   baseTime = 3600000*(43200 - 1200) = 151200000000.
> 
> I expect to see dumps every 5 years, and a pickup at year 15. Instead, I
> get dumps at iter:
> 0003628800 -> (3628800-3600000)*1200/86400/360 = 1.111 year
> 0003758400 -> (3758400-3600000)*1200/86400/360 = 6.111 year
> 0003888000 -> (3888000-3600000)*1200/86400/360 = 11.111 year
> 
> and a pickup at iter:
> 0003888000 -> (3888000-3600000)*1200/86400/360 = 11.111 year
> 
> Note that there is no dump at the initial iteration, 0003600000.
> 
> What am I doing wrong here?
> 
> Thanks, Samar
>