Re: Fwd: Help with ds336.0

[Robb Kambic <rkambic@xxxxxxxxxxxxxxxx>]

On Thu, 17 Jan 2008, Doug Schuster wrote:

> Hi Rob,
>
> A user noticed the below problem in data collected on motherlode.  Are there 
> any know bugs in
> the SYNOP to NetCDF decoder/encoder that might cause a problem encoding the 
> proper nominal and obs  times?
>
> Thanks,
> Doug
>
> Begin forwarded message:
>
> > From: Ilia Ilyin <ilia.ilyin@xxxxxxxxxxx>
> > Date: January 17, 2008 3:43:46 AM MST
> > To: schuster@xxxxxxxx
> > Subject: Help with ds336.0
> >
> > Dear Doug,
> >
> > I am trying to use data on observations from the data set ds336 for 
> > verification of meteorological fields generated by meteorological drivers 
> > (in particular, MM5). I come across a problem of interpretation of 
> > parameter called nominal time. For a number of stations in different daily 
> > files meteorological parameters refer to the same nominal time, but values 
> > of the parameters differ.


Doug,

this problem is caused by the report being sent multiple times with the 
later times the report having updated fields. the latest file will have 
the values for the latest report. I'll check the code to see if there are 
any errors and let you know if I find an error.

Robb...

> > For example, surface air temperature at station #71497 derived from file 
> > Surface_Synoptic_20071202_0000.nc for nominal time 119655360 s (02.12.2007, 
> > 00h.) is -15.8 C. However, in the previous day file 
> > (Surface_Synoptic_20071201_0000.nc) but at the same nominal time the 
> > temperature at this station is -21.4 C. What value should be used? Could 
> > you please explain me this, or, if not,  provide me with reference to 
> > documentation where this issue is discussed?
> >
> > Best wishes,
> > Ilia
> >
> > ********************************************************
> > * Ilia Ilyin                                           *
> > * Meteorological Synthesizing Centre East of EMEP      *
> > * Krasina pereulok, 16/1, 123056 Moscow, Russia,       *
> > * Tel 007 495 981 15 67                                *
> > * Fax 007 495 981 15 67                                *
> > * e-mail: ilia.ilyin@xxxxxxxxxxx                       *
> > * Internet: http://www.msceast.org                     *
> > ********************************************************

===============================================================================
Robb Kambic        			   Unidata Program Center
Software Engineer III			   Univ. Corp for Atmospheric Research
rkambic@xxxxxxxxxxxxxxxx		   WWW: http://www.unidata.ucar.edu/
===============================================================================