Re: Lambert Conformal Grid

From: Agnes Lim Huei Ni <alim_at_nyahnyahspammersnyahnyah>
Date: Thu Aug 29 2013 - 19:33:40 MDT

Hi Dave,

Thanks a lot, the 2nd figure did give me a good perspective that
everything is correct.
When it was in 2d as in figure 1, I didn't have a perspective on how the
grids will flow.
I tried to add grid lines on it but without success.

Agnes

On 8/29/13 6:09 PM, David Brown wrote:
> Hi Agnes,
> You did not specify what "did not look right" about your earlier
> script, but I am guessing that perhaps you meant that the "native"
> projection does not seem to line up with the edge of the plot on the
> left and bottom sides of the plot.
> That is because the data has missing values in those areas. I have
> played with your script some, eliminating the panelling and changing
> the variable to the first level of the PRES variable (because it's
> relation to the topography allows you to check the alignment with the
> map projection outlines). I also changed the color map and set the
> missing value fill color to green to make it clear which areas have
> missing data. I plotted both in the native projection and
> in an orthographic projection. The results strongly suggest that the
> NCL plots are correct. I am attaching them here, along with the
> script, as mangled by me, so you can see how these results were obtained.
> -dave
>
>
>
>
>
>
>
>
> On Aug 28, 2013, at 7:42 PM, Agnes Lim Huei Ni <alim@ssec.wisc.edu
> <mailto:alim@ssec.wisc.edu>> wrote:
>
>> Hi Dave,
>>
>> I apologist for the typo. I have put my code, the data and the figure
>> that i generated in the link below.
>>
>> ftp://ftp.ssec.wisc.edu/pub/ssec/alim/
>>
>>
>> Thanks
>> Agnes
>>
>> On 8/28/13 6:47 PM, David Brown wrote:
>>> It doesn't seem to be there:
>>>
>>> 230 Anonymous access granted, restrictions apply
>>> Remote system type is UNIX.
>>> Using binary mode to transfer files.
>>> ftp> cd pub/alim
>>> 250 CWD command successful
>>> ftp> ls
>>> 227 Entering Passive Mode (128,104,108,86,250,150).
>>> 150 Opening ASCII mode data connection for file list
>>> drwxr-xr-x 2 ftp ftp 116 Jun 14 18:31 GEO-HYPER_OSSE
>>> drwxr-xr-x 5 ftp ftp 12288 Aug 27 16:15 model_levels
>>> 226 Transfer complete
>>> ftp> cd GEO-HYPER_OSSE
>>> 250 CWD command successful
>>> ftp> ls
>>> 227 Entering Passive Mode (128,104,108,86,252,184).
>>> 150 Opening ASCII mode data connection for file list
>>> -rw-r--r-- 1 ftp ftp 231424 Apr 26 15:00 GEO-HYPER
>>> OSSE_exp_config.ppt
>>> -rw-r--r-- 1 ftp ftp 54272 Apr 26 14:54
>>> Geo-hyper_osse_experiment.doc
>>> -rw-r--r-- 1 ftp ftp 13106721 Jun 14 18:31 ectc_simcot.gif
>>> 226 Transfer complete
>>> ftp> cd ../model_levels
>>> 250 CWD command successful
>>> ftp> ls
>>> 227 Entering Passive Mode (128,104,108,86,213,27).
>>> 150 Opening ASCII mode data connection for file list
>>> -rw-r--r-- 1 ftp ftp 713735 Aug 27 16:20
>>> Inc_1st_outer_loop.pptx
>>> -rw-r--r-- 1 ftp ftp 3416576 Aug 21 04:01
>>> Model_top_vart_res_081213.ppt
>>> -rw-r--r-- 1 ftp ftp 17796 Mar 8 15:28 P.png
>>> -rw-r--r-- 1 ftp ftp 13671 Mar 8 15:28 P_zoom.png
>>> -rw-r--r-- 1 ftp ftp 1278464 Feb 21 2013
>>> Vert_Res_tests.ppt
>>> -rw-r--r-- 1 ftp ftp 940032 Mar 9 03:44
>>> Vert_Res_tests_II.ppt
>>> drwxr-xr-x 2 ftp ftp 12288 Jun 12 03:40 airs
>>> -rw-r--r-- 1 ftp ftp 16505451 May 14 16:19 gsi_profiles
>>> -rw-r--r-- 1 ftp ftp 15446618 May 23 02:13
>>> gsi_profiles_0.5Pa
>>> drwxr-xr-x 2 ftp ftp 8192 Jun 12 18:21 hirs-3
>>> drwxr-xr-x 2 ftp ftp 16384 Jun 13 20:24 iasi
>>> -rw-r--r-- 1 ftp ftp 15731 Mar 8 15:28 lnP.png
>>> -rw-r--r-- 1 ftp ftp 10305 Jun 10 20:18
>>> sigma_levels_0_0.01.png
>>> -rw-r--r-- 1 ftp ftp 11186 Jun 10 20:18
>>> sigma_levels_0_1.png
>>> 226 Transfer complete
>>> ftp> pwd
>>> 257 "/pub/alim/model_levels" is the current directory
>>>
>>> ======
>>>
>>> It would be helpful to have your code and the grib file as well
>>> (unless it's a simple fix -- but I can't tell with out the picture).
>>> Thanks.
>>> -dave
>>>
>>>
>>> On Aug 28, 2013, at 5:15 PM, Agnes Lim Huei Ni <alim@ssec.wisc.edu
>>> <mailto:alim@ssec.wisc.edu>> wrote:
>>>
>>>> Hi David,
>>>>
>>>> Thanks for clarifying what the purpose of the masking option is for.
>>>>
>>>> I have set my resource options to what you suggested but
>>>> coordinates still does not look right.
>>>> I have placed the figure at
>>>> ftp.ssec.wisc.edu/pub/alim/T_test.pdf
>>>>
>>>> Please advise.
>>>>
>>>> Thanks
>>>> Agnes
>>>>
>>>> PS The following is the code segment for the plotting.
>>>>
>>>> res@gsnSpreadColors = True
>>>> res@mpLandFillColor = -1 ; set land to be transperant
>>>> res@mpOutlineOn = True
>>>> res@mpOutlineBoundarySets = "AllBoundaries"
>>>> res@mpProjection = "LambertConformal"
>>>> res@mpLambertParallel1F = lat2d@Latin1 ; ncl adds
>>>> from grib file
>>>> res@mpLambertParallel2F = lat2d@Latin2 ; ncl adds
>>>> from grib file
>>>> res@mpLambertMeridianF = lat2d@Lov ; ncl adds
>>>> from grib file
>>>> res@mpLimitMode = "corners"
>>>> res@mpLeftCornerLonF = lon2d@corners(0) ; (-168.719)
>>>> res@mpLeftCornerLatF = lat2d@corners(0) ; (-8.035)
>>>> res@mpRightCornerLonF = lon2d@corners(2) ; (-45.67911)
>>>> res@mpRightCornerLatF = lat2d@corners(2) ; (42.22018)
>>>> res@tfDoNDCOverlay = True
>>>> res@cnFillOn = True
>>>> res@cnLinesOn = False
>>>> res@cnLineLabelsOn = False
>>>> res@lbBoxLinesOn = True
>>>>
>>>> res@gsnAddCyclic = False
>>>> res@gsnDraw=False
>>>> res@gsnFrame=False
>>>> res@mpEllipticalBoundary = False
>>>> res@tmXBLabelFontHeightF = 0.01 ; resize tick
>>>> labels
>>>> res@tmYLLabelFontHeightF = 0.01
>>>> res@pmTickMarkDisplayMode = "Always"
>>>> res@lbLabelAutoStride = True
>>>> res@lbLabelBarOn = False
>>>> res@lbLabelFontHeightF=0.012
>>>> res@cnLevelSelectionMode = "ExplicitLevels"
>>>> res@cnLevels=(/-2.0, -1.5, -1.0, -0.5, 0.5, 1, 1.5, 2.0/)
>>>>
>>>> plot(0)=gsn_csm_contour_map(wks,inc(97,:,:), res)
>>>> plot(1)=gsn_csm_contour_map(wks,inc(94,:,:), res)
>>>> plot(2)=gsn_csm_contour_map(wks,inc(91,:,:), res)
>>>> plot(3)=gsn_csm_contour_map(wks,inc(88,:,:), res)
>>>> plot(4)=gsn_csm_contour_map(wks,inc(85,:,:), res)
>>>> plot(5)=gsn_csm_contour_map(wks,inc(82,:,:), res)
>>>>
>>>> resP=True
>>>> resPgsnPanelFigureStngsPerimOn=False
>>>> resP@gsnPanelLabelBar = False
>>>> resP@lbLabelFontHeightF=0.012
>>>> resP@pmLabelBarOrthogonalPosF = -0.05
>>>> resP@lbLabelStride = 1
>>>> resP@gsnPanelFigureStrings= (/"a)","b)","c)","d)","e)","f)"/)
>>>> gsn_panel(wks, plot, (/3,2/), resP)
>>>> gsnMaximize = True
>>>>
>>>>
>>>> On 8/28/13 4:53 PM, David Brown wrote:
>>>>> Agnes (and Rick):
>>>>> Well the model this GRIB is associated with is the "North Pacific
>>>>> Hurricane Wave Model" so it seems natural that it is centered over
>>>>> the Pacific. I am attaching a plot of the area covered by the data as
>>>>> specified in the GRIB lat/lon coordinate attributes. As the
>>>>> message indicates, the error stems from attempting to mask the
>>>>> conformal projection. The masking routine expects the plot to lie
>>>>> solely in the Northern or Southern
>>>>> hemisphere. That is because its purpose is to remove the "hole" in
>>>>> the projection that occurs wrapping around the pole. See the two
>>>>> frames of the first plot in the masked LC example page if this is
>>>>> not clear (http://www.ncl.ucar.edu/Applications/lcmask.shtml).
>>>>>
>>>>> For a regional LC projection that does not include the polar area,
>>>>> there is no need to mask the projection.
>>>>> So the first suggestion is to remove:
>>>>> res@gsnMaskLambertConformal = True
>>>>>
>>>>> Second if you set up the projection based on the lat/lon variable
>>>>> attributes in the GRIB file you can do a "native" projection,
>>>>> which is faster and presents the data as the GRIB producer output it.
>>>>> The projection resources you would use are:
>>>>>
>>>>> res@mpProjection = "lambertconforma
>>>>> res@mpLambertParallel1F = lat2d@Latin1 ; (36.228)
>>>>> res@mpLambertParallel2F = lat2d@Latin2 ; (36.228)
>>>>> res@mpLambertMeridianF" : lat2d@Lov ; (-122.246)
>>>>> res@mpLimitMode = "corners"
>>>>> res@mpLeftCornerLonF = lon2d@corners(0) ; (-168.719)
>>>>> res@mpLeftCornerLatF = lat2d@corners(0) ; (-8.035)
>>>>> res@mpRightCornerLonF = lon2d@corners(2) : (-45.67911)
>>>>> res@mpRightCornerLatF = lat2d@corners(2) ; (42.22018)
>>>>>
>>>>> Additionally set
>>>>>
>>>>> res@tfDoNDCOverlay = True
>>>>>
>>>>> and don't use the lat2d, lon2d coordinate attributes.
>>>>>
>>>>> However, you can use any projection for this data if you don't set
>>>>> tfDoNDCOverlay and do use the lat2d, lon2d coordinates.
>>>>>
>>>>> Hope this helps.
>>>>> -dave
>>>>> <Mail Attachment.png>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> On Aug 28, 2013, at 1:31 PM, Rick Brownrigg <brownrig@ucar.edu
>>>>> <mailto:brownrig@ucar.edu>> wrote:
>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> I don't know about the source of the error message, but what
>>>>>> strikes me is the value for mpLambertMeridianF is somewhat
>>>>>> unusual for a map of CONUS: a value of -125 puts the center of
>>>>>> projection off the coast of California. A value of -98 would be
>>>>>> more typical.
>>>>>>
>>>>>> Just FWIW…
>>>>>> Rick
>>>>>>
>>>>>> On Aug 28, 2013, at 1:21 PM, Agnes Lim Huei Ni
>>>>>> <alim@ssec.wisc.edu <mailto:alim@ssec.wisc.edu>> wrote:
>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> I have a grb file that contains temperature covering CONUS and part
>>>>>>> south america.
>>>>>>> I had set the following resources to plot it on a lambert
>>>>>>> conformal grid
>>>>>>> res@mpProjection = "LambertConformal"
>>>>>>> res@mpLambertParallel1F = 20.000
>>>>>>> res@mpLambertParallel2F = 40.000
>>>>>>> res@mpLambertMeridianF = -125.000
>>>>>>> res@gsnMaskLambertConformal = True
>>>>>>>
>>>>>>> The following errors appear
>>>>>>> (0) mask_lambert_conformal: warning: you are not authorized
>>>>>>> to specify.
>>>>>>> (0) a maxlat that is above the equator and a minlat that is
>>>>>>> below
>>>>>>> (0) the equator. No masking will take place.
>>>>>>>
>>>>>>> The information in the grb file for T, latitude and longitude in
>>>>>>> the
>>>>>>> data file are listed belowe.
>>>>>>>
>>>>>>> Please advice.
>>>>>>>
>>>>>>> Thanks
>>>>>>> Agnes
>>>>>>>
>>>>>>> Variable: anal_T
>>>>>>> Type: float
>>>>>>> Total Size: 479364732 bytes
>>>>>>> 119841183 values
>>>>>>> Number of Dimensions: 3
>>>>>>> Dimensions and sizes: [lv_HYBL0 | 99] x [g3_x_1 | 869] x
>>>>>>> [g3_y_2 | 1393]
>>>>>>> Coordinates:
>>>>>>> lv_HYBL0: [1..99]
>>>>>>> Number Of Attributes: 13
>>>>>>> center : US National Weather Service - NCEP (WMC)
>>>>>>> long_name : Temperature
>>>>>>> units : K
>>>>>>> _FillValue : 1e+20
>>>>>>> coordinates : g3_lat_1 g3_lon_2
>>>>>>> level_indicator : 109
>>>>>>> gds_grid_type : 3
>>>>>>> parameter_table_version : 2
>>>>>>> parameter_number : 11
>>>>>>> model : North Pacific Hurricane Wave Model
>>>>>>> forecast_time : 0
>>>>>>> forecast_time_units : hours
>>>>>>> initial_time : 05/24/2008 (00:00)
>>>>>>>
>>>>>>> Variable: lat2d
>>>>>>> Type: float
>>>>>>> Total Size: 4842068 bytes
>>>>>>> 1210517 values
>>>>>>> Number of Dimensions: 2
>>>>>>> Dimensions and sizes: [g3_x_1 | 869] x [g3_y_2 | 1393]
>>>>>>> Coordinates:
>>>>>>> Number Of Attributes: 11
>>>>>>> corners : ( -8.035, -5.586509, 42.22018, 36.89176 )
>>>>>>> long_name : latitude
>>>>>>> GridType : Lambert Conformal Secant or Tangent, Conical or
>>>>>>> bipolar
>>>>>>> units : degrees_north
>>>>>>> Latin2 : 36.228
>>>>>>> Latin1 : 36.228
>>>>>>> Dy : 7920
>>>>>>> Dx : 8774
>>>>>>> Lov : -122.246
>>>>>>> Lo1 : -168.719
>>>>>>> La1 : -8.035
>>>>>>>
>>>>>>> Variable: lon2d
>>>>>>> Type: float
>>>>>>> Total Size: 4842068 bytes
>>>>>>> 1210517 values
>>>>>>> Number of Dimensions: 2
>>>>>>> Dimensions and sizes: [g3_x_1 | 869] x [g3_y_2 | 1393]
>>>>>>> Coordinates:
>>>>>>> Number Of Attributes: 11
>>>>>>> corners : ( -168.719, -80.83456, -45.67911, 154.7749 )
>>>>>>> long_name : longitude
>>>>>>> GridType : Lambert Conformal Secant or Tangent, Conical or
>>>>>>> bipolar
>>>>>>> units : degrees_east
>>>>>>> Latin2 : 36.228
>>>>>>> Latin1 : 36.228
>>>>>>> Dy : 7920
>>>>>>> Dx : 8774
>>>>>>> Lov : -122.246
>>>>>>> Lo1 : -168.719
>>>>>>> La1 : -8.035
>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> ncl-talk mailing list
>>>>>>> List instructions, subscriber options, unsubscribe:
>>>>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>>>>
>>>>>> _______________________________________________
>>>>>> ncl-talk mailing list
>>>>>> List instructions, subscriber options, unsubscribe:
>>>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>>>
>>>>
>>>> _______________________________________________
>>>> ncl-talk mailing list
>>>> List instructions, subscriber options, unsubscribe:
>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>>
>> _______________________________________________
>> ncl-talk mailing list
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>

_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Thu Aug 29 19:33:51 2013

This archive was generated by hypermail 2.1.8 : Fri Aug 30 2013 - 14:04:57 MDT