[Met_help] point_stat in MET

Tue Apr 20 12:47:23 MDT 2010

Marlous,

Great.  Glad that did the trick.  Just let us know if any more issues come up.

John

Marlous Jonker wrote:
> Hi John!
> 
> Thanks for the answer. This solves the problem. We adapted the
> post-processing.
> 
> Thanks again for your help!
> 
> Cheers,
> Marlous
> 
> 
> 
> -----Oorspronkelijk bericht-----
> Van: John Halley Gotway [mailto:johnhg at ucar.edu] 
> Verzonden: maandag 19 april 2010 19:57
> Aan: Marlous Jonker
> CC: met_help
> Onderwerp: Re: point_stat in MET
> 
> Marlous,
> 
> OK, I think I've figured it out.  The problem is actually in your GRIB
> file.  The scanning mode flag in the Grid Description Section of your
> GRIB file is set to 0 when it should probably be set to 64.
>  When MET reads your GRIB file, it thinks the lower boundary of your
> domain is 70 degrees N, when in fact that should be the upper boundary.
> 
> I ran this GRIB file through MODE and saw that it didn't plot the domain
> where it should be.
> 
> When I manually changed the scanning mode flag to 64, I saw two things:
> - The plot MODE generated is now in the correct location on earth.
> - The number of matched pairs in Point-Stat increased from 7 to 19,943.
> 
> You have two options...
> (1) Fix how the GRIB files are being generated and set the scanning mode
> flag to 64.  This is Octet 28 of the Grid Description Section in GRIB
> (http://www.nco.ncep.noaa.gov/pmb/docs/on388/tabled.html).  Try running:
> wgrib -V -GDS10 wrf_main_9km_eu_2010041406_25.grb
> 
>   Here's the output of that wgrib command:
>   ----------------------------------------------------
>   rec 2:212034:date 2010041405 DPT kpds5=17 kpds6=105 kpds7=2
> levels=(0,2) grid=255 2 m above gnd 25hr fcst:
>   DPT=Dew point temp. [K]
>   timerange 10 P1 0 P2 25 TimeU 1  nx 240 ny 471 GDS grid 0 num_in_ave 0
> missing 0
>   center 7 subcenter 0 process 89 Table 2 scan: WE:NS winds(grid)
>   latlon: lat  35.224000 to 70.004000 by 0.074000  nxny 113040
>           long -11.850000 to 24.000000 by 0.150000, (240 x 471) scan 0
> mode 136 bdsgrid 1
>   GDS10(1..32)=
>        1:   0   0  32   0 255   0   0 240   1 215   0 137 152 128  46
> 74 136   1  17 116
>       21:   0  93 192   0 150   0  74   0   0   0   0   0
>   min/max data 262.908 289.106  num bits 15  BDS_Ref 262908  DecScale 3
> BinScale 0
>   ----------------------------------------------------
> 
>   That 28th entry in the GDS section is 0 but should be 64.
> 
> (2) The second option is to modify the MET source code so that it ALWAYS
> uses a value of 64 instead of 0 for the scanning mode flag.  This is a
> short-term hack to address your immediate problem.  Copy the attached
> file "read_grib.cc" into METv2.0/lib/vx_met_util/. and recompile MET.
> 
> Ultimately, it would be better to fix the generation of the GRIB file.
> 
> Hope that helps.
> 
> John
> 
> Marlous Jonker wrote:
>> Hi John,
>>
>> Here is the link again:
>>
>> https://www.wetransfer.com/dl.php?code=3hAnj9Pu&hash=0761aeb719a21cdcd
>> f4
>> 4dde0bbc3f2f06cbd3d27a7af90ab8085ee08daec65549b04c70955cf1
>>
>> I hope it works! Otherwise I'll have to try and zip the files.
>>
>> Cheers,
>> Marlous
>>
>>
>> -----Oorspronkelijk bericht-----
>> Van: John Halley Gotway [mailto:johnhg at ucar.edu]
>> Verzonden: vrijdag 16 april 2010 20:47
>> Aan: Marlous Jonker
>> CC: met_help
>> Onderwerp: Re: point_stat in MET
>>
>> Marlous,
>>
>> I'd be happy to take a look, but unfortunately the link you sent 
>> didn't work for me.  When I pasted into the browser, it couldn't find
> it.
>> Could you instead post it to our anonymous ftp site:
>> ftp ftp.rap.ucar.edu
>> username = anonymous
>> password = "your email address"
>> cd incoming/irap/met_help/jonker_data
>> put "your files"
>> bye
>>
>> Please try posting them there and I'll take a look.
>>
>> Thanks,
>> John
>>
>> Marlous Jonker wrote:
>>> Hi John!
>>>
>>>  
>>>
>>> How are you doing? Half a year ago I had a few questions about 
>>> getting started with MET using the sample data from the MET package. 
>>> Nowadays
>> I
>>> am attempting to make an operational verification process with MET 
>>> for WRF and other mesoscale models. From this a new question arises.
>>>
>>>  
>>>
>>> When trying to run Point_stat with a WRF gribfile and ascii
>> observation
>>> file (converted to netcdf with MET), I find that Point_stat uses very
> 
>>> few matches pares: only seven (even when the grib file covers most of
> 
>>> Europe and the observation file contains over 136000 observations).
>> When
>>> trying to simplify the problem and using only one station (of which
>> I'm
>>> sure it's right in the middle of my domain: station 6260, de Bilt, 
>>> The
>>> Netherlands) Point_stat finds no matching pairs at all.
>>>
>>> Below you find the link to both the observation files (ascii and 
>>> netcdf), the config file and the WRF grib I used. They are too large
>> to
>>> send by e-mail.
>>>
>>>  
>>>
>>>
>> https://www.wetransfer.com/dl.phpcode=3hAnj9Pu&hash=0761aeb719a21cdcdf
>> 44
>>> dde0bbc3f2f06cbd3d27a7af90ab8085ee08daec65549b04c70955cf1
>>>
>>> I hope you can help me to find the problem and solution.
>>>
>>>  
>>>
>>> Thanks in advance,
>>>
>>>  
>>>
>>> Marlous Jonker
>>>
>>>  
>>>
>>> -------------------------------------------------------------------
>>>
>>>   Marlous Jonker
>>>
>>>   Meteorological Researcher
>>>
>>>   Meteo Consult BV, Wageningen, the Netherlands
>>>
>>>   Tel: +31 (0)317 399872
>>>
>>>   Email: M.Jonker at weer.nl
>>>
>>>   www: research.meteogroup.com
>>>
>>> -------------------------------------------------------------------
>>>
>>>  
>>>
>>>
>>>
>>
> 
> 