[Met_help] [rt.rap.ucar.edu #75154] History for FW: matched pairs in point_stat
John Halley Gotway via RT
met_help at ucar.edu
Thu Feb 18 12:20:25 MST 2016
----------------------------------------------------------------
Initial Request
----------------------------------------------------------------
Hello,
I am using point_stat to create statistics comparing MADIS data to model output. I have 2 questions:
1) The regrid option is available in the PointStatConfig file. Does point_stat ever use that information to regrid the point observations? I entered values, but there was nothing in the output that indicated that point_stat actually regridded any observations.
2) Does point_stat create matched pairs based on the observation locations? I am comparing model output from 2 different grids with differing horizontal grid spacing to MADIS data. I ultimately want to compare model output at each observation point. I used a CONUS masking polyline to ensure that the statistics used only observations within the CONUS region. However, some observation points are included in one matching pair file and not the other (even though the observation point falls within the CONUS masking polyline and within the model domain).
Any help is appreciated!
Regards,
Leela Watson
Leela R. Watson, PhD
Meteorologist
(321) 866-0229
1980 N. Atlantic Ave., Suite 830
Cocoa Beach, FL 32931
www.ensco.com<http://www.ensco.com/>
[cid:image001.gif at 01D16A3F.82DA8D20]
Innovation. Collaboration. Solutions. Success.
________________________________
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The U.S. Export Control Laws regulate the export and re-export of technology originating in the United States. This includes the electronic transmission of information and software to foreign countries and to certain foreign nationals. Recipient agrees to abide by these laws and their regulations -- including the U.S. Department of Commerce Export Administration Regulations and the U.S. Department of State International Traffic in Arms Regulations -- and not to transfer, by electronic transmission or otherwise, any content derived from this email to either a foreign national or a foreign destination in violation of such laws.
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Complete Ticket History
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Subject: FW: matched pairs in point_stat
From: John Halley Gotway
Time: Thu Feb 18 10:15:38 2016
Leela,
The "regrid" section of the configuration file is new for MET version
5.1.
As you may have read, it enables the MET tools to regrid the gridded
datasets they read on the fly. This option is very useful for the
tools
which do grid-to-grid comparisons, like Grid-Stat, MODE, Ensemble-
Stat, and
Wavelet-Stat. That way you don't need to regrid one to other ahead of
time... instead, you can let MET do the regridding for you on the fly.
For Point-Stat, the automated regridding functionality is much less
useful. For each point observation you pass to Point-Stat, it uses
the
interpolation options you specify in the "interp" section of the
configuration file to interpolate the forecast points surrounding that
observation to its lat/lon location. The vast majority of the time
users
will not want to regrid their forecast data prior to evaluating it.
You
would just evaluate it on its native domain. However, I can think of
scenarios where it may be useful.
Next, I see that you're running Point-Stat on the output of 2
different
models using a CONUS masking region but are getting (slightly)
different
sets of matched pairs. I'd suggest looking at the lat/lon of the
stations
which appear in one, but not the other. If they are right along the
CONUS
boundary, it could easily be an edge effect. Since their grid spacing
differs, the observation's lat/lon may be slightly inside one but not
the
other.
Point-Stat uses the observation lat/lon to find the nearest forecast
grid
point. If that forecast grid point is not within the CONUS masking
region,
that observation is not used. For your 2 grids, the nearest grid
point may
be inside CONUS in one and outside in the other. Here's an experiment
you
could try:
- Try using Point-Stat to evaluate both models on the same grid.
- Run the first one through Point-Stat doing no regridding.
- Run the second one through Point-Stat, but in the "regrid" section,
set
to_grid = "/path/to/sample/model1/file"; That will verify both models
on
the grid of the first model.
- Then check your output to see if the set of matched pairs are now
the
same. If so, it's most likely this edge effect.
Hope that helps.
Thanks,
John Halley Gotway
On Thu, Feb 18, 2016 at 9:32 AM, Watson.Leela via RT
<met_help at ucar.edu>
wrote:
>
> Thu Feb 18 09:32:46 2016: Request 75154 was acted upon.
> Transaction: Ticket created by watson.leela at ensco.com
> Queue: met_help
> Subject: FW: matched pairs in point_stat
> Owner: Nobody
> Requestors: watson.leela at ensco.com
> Status: new
> Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=75154 >
>
>
> Hello,
>
> I am using point_stat to create statistics comparing MADIS data to
model
> output. I have 2 questions:
>
> 1) The regrid option is available in the PointStatConfig file.
Does
> point_stat ever use that information to regrid the point
observations? I
> entered values, but there was nothing in the output that indicated
that
> point_stat actually regridded any observations.
>
> 2) Does point_stat create matched pairs based on the
observation
> locations? I am comparing model output from 2 different grids with
> differing horizontal grid spacing to MADIS data. I ultimately want
to
> compare model output at each observation point. I used a CONUS
masking
> polyline to ensure that the statistics used only observations within
the
> CONUS region. However, some observation points are included in one
matching
> pair file and not the other (even though the observation point falls
within
> the CONUS masking polyline and within the model domain).
>
> Any help is appreciated!
>
> Regards,
>
> Leela Watson
>
>
> Leela R. Watson, PhD
> Meteorologist
> (321) 866-0229
> 1980 N. Atlantic Ave., Suite 830
> Cocoa Beach, FL 32931
> www.ensco.com<http://www.ensco.com/>
>
> [cid:image001.gif at 01D16A3F.82DA8D20]
> Innovation. Collaboration. Solutions. Success.
>
>
> ________________________________
> The information contained in this email message is intended only for
the
> use of the individual(s) to whom it is addressed and may contain
> information that is privileged and sensitive. If you are not the
intended
> recipient, or otherwise have received this communication in error,
please
> notify the sender immediately by email at the above referenced
address and
> note that any further dissemination, distribution or copying of this
> communication is strictly prohibited.
>
> The U.S. Export Control Laws regulate the export and re-export of
> technology originating in the United States. This includes the
electronic
> transmission of information and software to foreign countries and to
> certain foreign nationals. Recipient agrees to abide by these laws
and
> their regulations -- including the U.S. Department of Commerce
Export
> Administration Regulations and the U.S. Department of State
International
> Traffic in Arms Regulations -- and not to transfer, by electronic
> transmission or otherwise, any content derived from this email to
either a
> foreign national or a foreign destination in violation of such laws.
>
>
------------------------------------------------
Subject: RE: [rt.rap.ucar.edu #75154] FW: matched pairs in point_stat
From: Watson.Leela
Time: Thu Feb 18 12:15:13 2016
Thanks, John. Regridding the second model to match the first worked -
all the pairs matched.
-----Original Message-----
From: John Halley Gotway via RT [mailto:met_help at ucar.edu]
Sent: Thursday, February 18, 2016 12:16 PM
To: Watson.Leela <watson.leela at ensco.com>
Subject: Re: [rt.rap.ucar.edu #75154] FW: matched pairs in point_stat
Leela,
The "regrid" section of the configuration file is new for MET version
5.1.
As you may have read, it enables the MET tools to regrid the gridded
datasets they read on the fly. This option is very useful for the
tools which do grid-to-grid comparisons, like Grid-Stat, MODE,
Ensemble-Stat, and Wavelet-Stat. That way you don't need to regrid
one to other ahead of time... instead, you can let MET do the
regridding for you on the fly.
For Point-Stat, the automated regridding functionality is much less
useful. For each point observation you pass to Point-Stat, it uses
the interpolation options you specify in the "interp" section of the
configuration file to interpolate the forecast points surrounding that
observation to its lat/lon location. The vast majority of the time
users will not want to regrid their forecast data prior to evaluating
it. You would just evaluate it on its native domain. However, I can
think of scenarios where it may be useful.
Next, I see that you're running Point-Stat on the output of 2
different models using a CONUS masking region but are getting
(slightly) different sets of matched pairs. I'd suggest looking at
the lat/lon of the stations which appear in one, but not the other.
If they are right along the CONUS boundary, it could easily be an edge
effect. Since their grid spacing differs, the observation's lat/lon
may be slightly inside one but not the other.
Point-Stat uses the observation lat/lon to find the nearest forecast
grid point. If that forecast grid point is not within the CONUS
masking region, that observation is not used. For your 2 grids, the
nearest grid point may be inside CONUS in one and outside in the
other. Here's an experiment you could try:
- Try using Point-Stat to evaluate both models on the same grid.
- Run the first one through Point-Stat doing no regridding.
- Run the second one through Point-Stat, but in the "regrid" section,
set to_grid = "/path/to/sample/model1/file"; That will verify both
models on the grid of the first model.
- Then check your output to see if the set of matched pairs are now
the same. If so, it's most likely this edge effect.
Hope that helps.
Thanks,
John Halley Gotway
On Thu, Feb 18, 2016 at 9:32 AM, Watson.Leela via RT
<met_help at ucar.edu>
wrote:
>
> Thu Feb 18 09:32:46 2016: Request 75154 was acted upon.
> Transaction: Ticket created by watson.leela at ensco.com
> Queue: met_help
> Subject: FW: matched pairs in point_stat
> Owner: Nobody
> Requestors: watson.leela at ensco.com
> Status: new
> Ticket
> <URL:https://urldefense.proofpoint.com/v2/url?u=https-
3A__rt.rap.ucar.
> edu_rt_Ticket_Display.html-3Fid-3D75154&d=CwIDaQ&c=DsZY2bea7iNIzyp-
7sZ
>
0t0F2UfNQZUfZhEPCv_2wBI0&r=3hIcLkjkAbYAnF9nSSpXmz6tPCfcNxikaomnXfToBnc
>
&m=zFccatabTU8xrAPOAnRgX773Vspl22bwlXerpsVHVLw&s=csuLmliaSQbs5WUbQPmYD
> F0E15bRdS-x16oYw9S0cDM&e= >
>
>
> Hello,
>
> I am using point_stat to create statistics comparing MADIS data to
> model output. I have 2 questions:
>
> 1) The regrid option is available in the PointStatConfig file.
Does
> point_stat ever use that information to regrid the point
observations?
> I entered values, but there was nothing in the output that indicated
> that point_stat actually regridded any observations.
>
> 2) Does point_stat create matched pairs based on the
observation
> locations? I am comparing model output from 2 different grids with
> differing horizontal grid spacing to MADIS data. I ultimately want
to
> compare model output at each observation point. I used a CONUS
masking
> polyline to ensure that the statistics used only observations within
> the CONUS region. However, some observation points are included in
one
> matching pair file and not the other (even though the observation
> point falls within the CONUS masking polyline and within the model
domain).
>
> Any help is appreciated!
>
> Regards,
>
> Leela Watson
>
>
> Leela R. Watson, PhD
> Meteorologist
> (321) 866-0229
> 1980 N. Atlantic Ave., Suite 830
> Cocoa Beach, FL 32931
> www.ensco.com<http://www.ensco.com/>
>
> [cid:image001.gif at 01D16A3F.82DA8D20]
> Innovation. Collaboration. Solutions. Success.
>
>
> ________________________________
> The information contained in this email message is intended only for
> the use of the individual(s) to whom it is addressed and may contain
> information that is privileged and sensitive. If you are not the
> intended recipient, or otherwise have received this communication in
> error, please notify the sender immediately by email at the above
> referenced address and note that any further dissemination,
> distribution or copying of this communication is strictly
prohibited.
>
> The U.S. Export Control Laws regulate the export and re-export of
> technology originating in the United States. This includes the
> electronic transmission of information and software to foreign
> countries and to certain foreign nationals. Recipient agrees to
abide
> by these laws and their regulations -- including the U.S. Department
> of Commerce Export Administration Regulations and the U.S.
Department
> of State International Traffic in Arms Regulations -- and not to
> transfer, by electronic transmission or otherwise, any content
derived
> from this email to either a foreign national or a foreign
destination in violation of such laws.
>
>
The information contained in this email message is intended only for
the use of the individual(s) to whom it is addressed and may contain
information that is privileged and sensitive. If you are not the
intended recipient, or otherwise have received this communication in
error, please notify the sender immediately by email at the above
referenced address and note that any further dissemination,
distribution or copying of this communication is strictly prohibited.
The U.S. Export Control Laws regulate the export and re-export of
technology originating in the United States. This includes the
electronic transmission of information and software to foreign
countries and to certain foreign nationals. Recipient agrees to abide
by these laws and their regulations -- including the U.S. Department
of Commerce Export Administration Regulations and the U.S. Department
of State International Traffic in Arms Regulations -- and not to
transfer, by electronic transmission or otherwise, any content derived
from this email to either a foreign national or a foreign destination
in violation of such laws.
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