[Met_help] [rt.rap.ucar.edu #81646] History for setting quality marks of obs in MET

Thu Aug 17 11:44:34 MDT 2017

----------------------------------------------------------------
  Initial Request
----------------------------------------------------------------

Hi, there,

Tara had told me that when I need to compare my VSDB verification with MET
verification, that I need to use the same quality marks that are used in
VSDB in MET.  So she told me that I needed to set, in the point_stat config
file, the variable:

obs_quality    = [];

to something that reflects that I want to keep all quality marks of 3 or
less, so that should be set to:

obs_quality    = ["0", "1", "2", "3"];

Is this correct?  And can I set a different obs_quality setting differently
for different variables in the same configuration file?

What we did not talk about but I noticed in the PB2NC config file, there is
this variable:

quality_mark_thresh = 2

What does this mean and what should it be set to, so I keep all obs with a
quality mark of 3 or less?

Thanks!

Perry

----------------------------------------------------------------
  Complete Ticket History
----------------------------------------------------------------

Subject: setting quality marks of obs in MET
From: Julie Prestopnik
Time: Thu Aug 17 10:21:03 2017

Hi Perry.

Yes.  What you sent for obs_quality is correct.

The following information is from our User's Guide
(http://www.dtcenter.org/met/users/docs/users_guide/MET_Users_Guide_v6.0.pdf
):

// The "obs_quality" entry specifies the quality flag values that are
to be
// retained and used for verification.  An empty list signifies that
all
// point observations should be used, regardless of their quality flag
value.
// The quality flag values will vary depending on the original source
of the
// observations.  The quality flag values to retain should be
specified as
// an array of strings, even if the values themselves are numeric.
//
obs_quality = [ "1", "2", "3", "9" ];

And yes, you can set a different obs_quality setting for each variable
in
the obs.field entry.  So, for example:

obs = {
   field = [
      {
        name       = "SPFH";
        level      = [ "P500" ];
        cat_thresh = [ >80.0 ];
        obs_quality = [ "1", "2", "9" ];
      },

      {
        name       = "TMP";
        level      = [ "P500" ];
        cat_thresh = [ >273.0 ];
        obs_quality = [ "1", "2", "3", "4", "9" ];
      }
   ];

Regarding the "quality_mark_thresh" setting, also from our User's
Guide:

"Each observation has a quality mark value associated with it.  The
*quality_mark_thresh* is used to stratify out which quality marks will
be
retained."

Setting quality_mark_thresh =2, indicates that only observations with
quality marks less than or equal to 2 will be retained.  So, if you
would
like to keep all obs with a a quality mark of 3 or less, you would set
it
to 3:

quality_mark_thresh = 3

I hope that helps!  Please let us know if you have any other
questions.

Julie

On Thu, Aug 17, 2017 at 8:43 AM, perry.shafran at noaa.gov via RT <
met_help at ucar.edu> wrote:

>
> Thu Aug 17 08:43:13 2017: Request 81646 was acted upon.
> Transaction: Ticket created by perry.shafran at noaa.gov
>        Queue: met_help
>      Subject: setting quality marks of obs in MET
>        Owner: Nobody
>   Requestors: perry.shafran at noaa.gov
>       Status: new
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=81646 >
>
>
> Hi, there,
>
> Tara had told me that when I need to compare my VSDB verification
with MET
> verification, that I need to use the same quality marks that are
used in
> VSDB in MET.  So she told me that I needed to set, in the point_stat
config
> file, the variable:
>
> obs_quality    = [];
>
> to something that reflects that I want to keep all quality marks of
3 or
> less, so that should be set to:
>
> obs_quality    = ["0", "1", "2", "3"];
>
> Is this correct?  And can I set a different obs_quality setting
differently
> for different variables in the same configuration file?
>
> What we did not talk about but I noticed in the PB2NC config file,
there is
> this variable:
>
> quality_mark_thresh = 2
>
> What does this mean and what should it be set to, so I keep all obs
with a
> quality mark of 3 or less?
>
> Thanks!
>
> Perry
>
>

------------------------------------------------
Subject: setting quality marks of obs in MET
From: perry.shafran at noaa.gov
Time: Thu Aug 17 10:24:53 2017

Hi, Julie,

Thanks!  Yes that does help.  I should probably set both flags, one in
each
routine.

Perry

On Thu, Aug 17, 2017 at 12:21 PM, Julie Prestopnik via RT
<met_help at ucar.edu
> wrote:

> Hi Perry.
>
> Yes.  What you sent for obs_quality is correct.
>
> The following information is from our User's Guide
> (http://www.dtcenter.org/met/users/docs/users_guide/MET_
> Users_Guide_v6.0.pdf
> ):
>
> // The "obs_quality" entry specifies the quality flag values that
are to be
> // retained and used for verification.  An empty list signifies that
all
> // point observations should be used, regardless of their quality
flag
> value.
> // The quality flag values will vary depending on the original
source of
> the
> // observations.  The quality flag values to retain should be
specified as
> // an array of strings, even if the values themselves are numeric.
> //
> obs_quality = [ "1", "2", "3", "9" ];
>
> And yes, you can set a different obs_quality setting for each
variable in
> the obs.field entry.  So, for example:
>
> obs = {
>    field = [
>       {
>         name       = "SPFH";
>         level      = [ "P500" ];
>         cat_thresh = [ >80.0 ];
>         obs_quality = [ "1", "2", "9" ];
>       },
>
>       {
>         name       = "TMP";
>         level      = [ "P500" ];
>         cat_thresh = [ >273.0 ];
>         obs_quality = [ "1", "2", "3", "4", "9" ];
>       }
>    ];
>
> Regarding the "quality_mark_thresh" setting, also from our User's
Guide:
>
> "Each observation has a quality mark value associated with it.  The
> *quality_mark_thresh* is used to stratify out which quality marks
will be
> retained."
>
> Setting quality_mark_thresh =2, indicates that only observations
with
> quality marks less than or equal to 2 will be retained.  So, if you
would
> like to keep all obs with a a quality mark of 3 or less, you would
set it
> to 3:
>
> quality_mark_thresh = 3
>
> I hope that helps!  Please let us know if you have any other
questions.
>
> Julie
>
>
>
> On Thu, Aug 17, 2017 at 8:43 AM, perry.shafran at noaa.gov via RT <
> met_help at ucar.edu> wrote:
>
> >
> > Thu Aug 17 08:43:13 2017: Request 81646 was acted upon.
> > Transaction: Ticket created by perry.shafran at noaa.gov
> >        Queue: met_help
> >      Subject: setting quality marks of obs in MET
> >        Owner: Nobody
> >   Requestors: perry.shafran at noaa.gov
> >       Status: new
> >  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=81646 >
> >
> >
> > Hi, there,
> >
> > Tara had told me that when I need to compare my VSDB verification
with
> MET
> > verification, that I need to use the same quality marks that are
used in
> > VSDB in MET.  So she told me that I needed to set, in the
point_stat
> config
> > file, the variable:
> >
> > obs_quality    = [];
> >
> > to something that reflects that I want to keep all quality marks
of 3 or
> > less, so that should be set to:
> >
> > obs_quality    = ["0", "1", "2", "3"];
> >
> > Is this correct?  And can I set a different obs_quality setting
> differently
> > for different variables in the same configuration file?
> >
> > What we did not talk about but I noticed in the PB2NC config file,
there
> is
> > this variable:
> >
> > quality_mark_thresh = 2
> >
> > What does this mean and what should it be set to, so I keep all
obs with
> a
> > quality mark of 3 or less?
> >
> > Thanks!
> >
> > Perry
> >
> >
>
>

------------------------------------------------