[gradsusr] wrf output data in lambert projection plot problem

Jeffrey Duda jdduda at iastate.edu
Tue Feb 8 13:22:26 EST 2011 

Kai,
That is interesting.  Did you try using "set mproj lambert" for the ARWpost
file?  I also use Lambert conformal conic in my WRF runs and when I run
ARWpost on them and view them in Grads I don't get that.  I've attached a
sample image of what my data looks like in both ways.  If setting the
projection in Grads isn't giving you what you want then I'm not sure what to
say.  What version of Grads are you using?

Jeff

On Tue, Feb 8, 2011 at 12:10 PM, Fu Kai <sdfukai at gmail.com> wrote:

> Hi, Jeff,
>
> It is great to get your reply. I have tried the ARWpost program, but the
> shape of the figure is almost the same, so I think the problem maybe
> something else.
>
> The header of ctl file created by ARWpost and the figure plotted by
> GrADS is below, the wps namelist file is also attached.
>
> The ctl file header:
>
> dset ^test.dat
> options  byteswapped
> undef 1.e30
> title  OUTPUT FROM WRF V3.0.1.1 MODEL
> pdef   73  60 lcc  34.830  -81.030   37.000   30.500  60.00000  30.00000
> -98.00000  30000.000  30000.000
> xdef  224 linear  -94.99892   0.13513513
> ydef  166 linear   23.26906   0.13513513
> zdef   27 linear 1 1
> tdef    5 linear 12Z24JAN2000     180MN
>
> Test figure [image: case1ARWpost.png]
>
> namelist.wps:
>
> &share
>  wrf_core = 'ARW',
>  max_dom = 1,
>  start_date = '2000-01-24_12:00:00',
>  end_date   = '2000-01-25_12:00:00',
>  interval_seconds = 21600
>  io_form_geogrid = 2,
> /
> &geogrid
>  parent_id         =   1,
>  parent_grid_ratio =   1,
>  i_parent_start    =   1,
>  j_parent_start    =   1,
>  e_we              =  74,
>  e_sn              =  61,
>  geog_data_res     = '10m',
>  dx = 30000,
>  dy = 30000,
>  map_proj = 'lambert',
>  ref_lat   =  34.83,
>  ref_lon   = -81.03,
>  truelat1  = 30.0,
>  truelat2  =  60.0,
>  stand_lon = -98.0,
>  geog_data_path = '/home/kfu/WRF/WPS_GEOG/geog'
> /
>
>
> Thanks in advance.
>
> Kai Fu
>
>
> On Tue, Feb 8, 2011 at 12:20 PM, Jeffrey Duda <jdduda at iastate.edu> wrote:
>
>> You're seeing that because the model grid itself has certain projection.
>> It has nothing to do with how Grads is interpreting the data.  This is a WRF
>> thing.  It doesn't look like a Lambert Conformal Conic projection, however,
>> because I think if you do "set mproj lambert", your data should appear to be
>> a rectangle with parallel edges and the map behind it should be altered.
>> Your second figure does not show that, so perhaps you have some other
>> projection.  I am also a WRF user, but I use the ARWpost program to convert
>> WRF netCDF files to something Grads can read.  Since I don't use the
>> wrf2grads program, there could be something with that program that caused
>> the PDEF line in your control file to be something other than it is in the
>> model.
>>
>> Jeff Duda
>>
>>   On Tue, Feb 8, 2011 at 10:41 AM, Fu Kai <sdfukai at gmail.com> wrote:
>>
>>>   Dear GrADS Users,
>>>
>>> I am beginner to wrf and GrADS, and want to display the output data of
>>> wrf using GrADS, I used the wrf2grads program to get the ctl and dat file
>>> which are needed by GrADS. When I tried to plot the data, there seems to
>>> be a problem, the figure does not coincide with the lat and lon lines (Fig
>>> 1). I thought it was because the case uses a lambert projection, while the
>>> default projection used by GrADS seems to be Mercator, so I tried
>>> to use "set mproj lambert" in GrADS, but only get a small figure (Fig 2)
>>> which also seems not properly. Which command should I use to get a right
>>> figure.
>>>
>>> Any suggestion would be greatly appreciated.  The CTL file and the figure
>>> plotted are below.  I'm a new GrADS user, so if this is a newbie problem, I
>>> apologize in advance.
>>>
>>> CTL file created by wrf2grads program:
>>>
>>> dset ^wrfout_d01_2000-01-24_12:00:00.dat
>>> undef 1.e35
>>> pdef  73  60 lcc  28.171  -93.649    1.000    1.000  60.  30.  -98.000
>>> 30000.  30000.
>>> xdef  219 linear  -94.6   0.13513513
>>> ydef  160 linear   23.6   0.13513513
>>> zdef   27 levels
>>>     0.02849
>>>     0.09096
>>>     0.17899
>>>     0.29167
>>>     0.43435
>>>     0.61657
>>>     0.83989
>>>     1.17945
>>>     1.62939
>>>     2.10596
>>>     2.60960
>>>     3.34814
>>>     4.30997
>>>     5.27340
>>>     6.23490
>>>     7.19647
>>>     8.16307
>>>     9.13477
>>>    10.11029
>>>    11.10285
>>>    12.13382
>>>    13.21484
>>>    14.34895
>>>    15.53801
>>>    16.78960
>>>    18.11523
>>>    19.52641
>>> tdef         5 linear 12z24jan2000  1mn
>>> vars    8
>>> U               27 0 U Compoment of wind
>>> V               27 0 V Component of wind
>>> W               27 0 W Component of wind
>>> THETA           27 0 Theta
>>> TC              27 0 Temperature in C
>>> P               27 0 Pressure (HPa)
>>> Z               27 0 Height (m)
>>> HGT             0  0 Terrain Height
>>> endvars
>>>
>>> Fig. 1.
>>> [image: wrfout_d01_2000-01-24_12_00_00.png]
>>>
>>> Fig. 2.
>>> [image: wrfout_d01_2000-01-24_12_00_00lambert.png]
>>>
>>> Thanks in advance.
>>>
>>> Kai Fu
>>>
>>>
>>> _______________________________________________
>>> gradsusr mailing list
>>> gradsusr at gradsusr.org
>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>
>>>
>>
>>
>> --
>> Jeff Duda
>> Iowa State University
>> Meteorology Graduate Student
>> 3134 Agronomy Hall
>> www.meteor.iastate.edu/~jdduda <http://www.meteor.iastate.edu/%7Ejdduda>
>>
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>>
>>
>
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-- 
Jeff Duda
Iowa State University
Meteorology Graduate Student
3134 Agronomy Hall
www.meteor.iastate.edu/~jdduda
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