[gradsusr] daily anomaly

[Sujata Mandke]

Respecetd Muthuvel sir,
  
 Thanks a lot for help.

 I need further assistance in this problem, as I understood 
 your suggestions partly. Follows the details of the part of 
 your suggestions that I understood and the part that
 is not clear.

> Create two different climatology data sets, one for 
> and 365 days another for leap year with 366 days.
  
    This is clear.

> Set up repeated soft links for each year of data set respectively 
>to non-leap years and >leap years in analysis period (very easy 
> to do, couple of lines of unix scripts). Create a >single grads 
> ctl file or all these climo years.

    I do not  know how to create soft links (in unix scripts) 
     and how to create a single grads ctl file for two separate datasets
    (one for non-leap years climo and other for leap years climo).

>Open up your total field control field and this climo control file, 
> then you are in business. We did like this at CPC more than 
> two decades ago and we continue to do like this now as we work 
> with daily cdas fields. I hope this helps. Please email me 
> separately if you need further assistance. Good day!

     Opening two 'ctl' files and calculating difference between 
 control fields and climo field looks easier to do in grads script.


Regards and bets wishes
Dr. Sujata Mandke
Scientist,IITM,Pune-8

----- Original Message -----
From: Muthuvel Chelliah <muthuvel.chelliah at noaa.gov>
To: GrADS Users Forum <gradsusr at gradsusr.org>
Sent: Fri, 07 Sep 2012 20:22:55 +0530 (IST)
Subject: Re: [gradsusr] daily anomaly

Sujata,
Create two different climatology data sets, one for 365 days and another
for leap year with 366 days.
Set up repeated soft links for each year of data set respectively to
non-leap years and leap years
in analysis period (very easy to do, couple of lines of unix scripts).
Create a single grads ctl file
for all these climo years. Open up your total field control field and this
climo control file, then you are in business. We did like this at CPC more
than two decades ago and we continue to do like this now as we work with
daily cdas fields. I hope this helps. Please email me separately if you
need further assistance. Good day!
Muthu

On Fri, Sep 7, 2012 at 2:52 AM, Sujata Mandke <amin at tropmet.res.in> wrote:

>   Respected Narapusetty Sir,
>
>      Thanks for prompt reply and willingness to provide
>    further assistance in my problem. I will go thorugh your
>    article and then try to solve the problem.
>
>          However, you had solved the problem by
> calculating climatology. I am having longterm daily
>  climatology dataset, so there is no need to calculate climatology.
> Regards
> Sujata Mandke
> IITM,PUNE-8,INDIA.
>
> ----- Original Message -----
> From: Balachandrudu Narapusetty <bnarapus at gmu.edu>
> To: GrADS Users Forum <gradsusr at gradsusr.org>
> Cc: gradsusr at gradsusr.org
> Sent: Thu, 06 Sep 2012 20:10:31 +0530 (IST)
> Subject: Re: [gradsusr] daily anomaly
>
> Hi Dr. Sujata,
>
> I am happy to see somebody has same problem that I had some time ago. I
> solved it by estimating the climatology (and thereafter anomalies) using
> few harmonics.
>
> I am sure this article is useful in dealing with your problem:
>
> Narapusetty, Balachandrudu, Timothy DelSole, Michael K. Tippett, 2009:
> Optimal Estimation of the Climatological Mean. J. Climate, 22, 4845–4859.
> doi: http://dx.doi.org/10.1175/2009JCLI2944.1
>
> I am happy to provide further assistance if you have questions.
>
> Best regards,
> Bala
>
>
> ----- Original Message -----
> From: Sujata Mandke <amin at tropmet.res.in>
> Date: Thursday, September 6, 2012 7:24 am
> Subject: [gradsusr] daily anomaly
>
> > Dear Grads Users
> >    I wish to calculate daily OLR anomaly from
> >  the following datasets.
> >    I have daily OLR data (netcdf) for the period
> >   1Jun1974-31May2012. Also long term daily OLR
> >   climatology (netcdf) data for 365 days.
> >
> >   As such writting script for calculating daily
> >  anomaly is very simple. But how to tackle following
> >    two problems while calculating anomaly
> >
> > (i) Actual data is on Gregorian(real) calendar
> >    and thus has data for 366 days in leap years.
> > (ii) What to do with missing values?
> >
> > Does anybody has grads script to calculate daily
> > anomaly by taking care of above two problems.
> > Regards
> > Dr. Sujata Mandke,Scientist,
> > IITM,PUNE-8,INDIA.
> > _______________________________________________
> > gradsusr mailing list
> > gradsusr at gradsusr.org
> > http://gradsusr.org/mailman/listinfo/gradsusr
> >
>
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-- 

------------------------------------------------------------------
Dr.Muthuvel Chelliah, eMail:Muthuvel.Chelliah at noaa.gov
Rm.3008, Climate Prediction Center, Ph:(301) 683-3393
NCEP/NWS/NOAA/U.S.Dept.of Commerce,
5830, University Research Court, NCWCP
College Park, MD 20740.